AC power interruption and / or dip detection device

Abstract

To solve a problem in which, for the detection of momentary interruption and / or momentary low, it is important to detect the voltage 0 V (zero cross point) and to obtain a time for half the wavelength of an AC power supply voltage signal, and in the past, zero cross detection has been performed by a single photocoupler from a signal that has been full-wave rectified by a rectifier circuit, but it is difficult to obtain the zero-cross point and half-wavelength time with high accuracy due to deviation from the ideal waveform.SOLUTION: By using two photocouplers without full-wave rectification, a zero cross point can be detected with the minimum effect of waveform deviation during rectification and a difference in an operating threshold of the photocoupler, such that the time with a voltage of 0 V can be obtained with high accuracy. It is possible to detect momentary interruptions with high accuracy. Since the zero cross point can be detected with high accuracy, the time required for half a wavelength to detect the instantaneous drop can be detected with high accuracy.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a device for detecting momentary interruptions and / or momentary sags in AC voltage. [Background technology]

[0002] A momentary interruption is when the supply of commercial power is temporarily stopped (for half a cycle or one minute) and the AC voltage or neutral reference voltage is 0V. A momentary sag is when the supply of commercial power is not completely stopped, but the AC voltage drops temporarily (for half a cycle or one minute). Tokyo Electric Power Company's general commercial AC 100V is 50Hz, so a half cycle is 10ms. When a momentary interruption occurs, production equipment may stop, medical equipment in hospitals may stop, and unprotected PC hard disks may be destroyed if the heads are not retracted in time. A momentary drop may also cause UPS and other equipment to malfunction, and magnet switch-type motors may stop. For this reason, it is necessary to detect the occurrence of momentary interruptions and momentary drops and have the necessary equipment take appropriate action. After detection, data should be evacuated, the system should transition to a state where there is no impact even if the power is turned off, or it should switch to an emergency power source. Since a momentary interruption results in a sustained state of 0V voltage, it is important to detect the moment when the voltage is 0V and the duration of that state. In addition, for momentary drops, voltage fluctuations are detected by calculating voltage value information every half cycle and comparing it to see if it has dropped below the normal value.

[0003] Conventional zero-crossing detection involves full-wave rectifying an AC voltage and using a photocoupler that uses the full-wave rectified output voltage as an input signal. The period during which the phototransistor that constitutes the photocoupler is off (non-conductive state between the collector and emitter) is measured and the zero-crossing point is detected based on that period.

[0004] The technology related to the document 1 will be described with reference to FIG. 18. FIG. 18 shows a heater control device (1801) that controls turning on a heater (1811) at a zero-cross point to prevent flicker (flickering of fluorescent lamps, cathode ray tubes, etc.), and includes a zero-cross detection device (1802) that detects the zero-cross point. This heater control device has a circuit configuration as shown in FIG. 18(a). The zero-cross detection device (1802) includes a rectifier circuit (1804) that full-wave rectifies the AC voltage supplied from a power source (1803), and a photocoupler (1805) that receives the output voltage of the rectifier circuit (1804) as an input signal. The photocoupler (1805) is composed of a photodiode D1 and a phototransistor Tr1, and the anode of the photodiode D1 is connected to the output of the rectifier circuit (1804) via a resistor R1, and the cathode of the photodiode D1 is connected to ground.

[0005] The collector of the phototransistor Tr1 is connected to a DC power supply VDD via a resistor R2 and is also connected to the base of the transistor Tr2, and the emitter of the phototransistor Tr1 is connected to ground. The collector of the transistor Tr2 is connected to a DC power supply VDD via a resistor R3, and the emitter of the transistor Tr2 is connected to ground. The control unit (1806) also has a zero-cross time measurement means (1807), a delay time calculation means (1809), and a delay means (1810), and is connected to the collector of the transistor Tr2 and the switch unit (1808).

[0006] Also, (b) of Fig. 18 shows the voltage waveform of the AC power supply (1803), (c) of Fig. 18 shows the input signal waveform of the photocoupler (1805) (output voltage waveform of the rectifier circuit (1804)), (d) of Fig. 18 shows the waveform of the collector output of the transistor Tr2, and (e) of Fig. 18 shows the waveform of the heater control signal.

[0007] The AC voltage (FIG. 18(b)) from the AC power supply (1803) is full-wave rectified by the rectifier circuit (1804), and the full-wave rectified voltage (FIG. 18(c)) is applied to the light-emitting diode D1 of the photocoupler (1805) via the resistor R1. As a result, a forward current proportional to the voltage of the AC power supply (1803) flows through the light-emitting diode D1, and this forward current causes the light-emitting diode D1 to emit light.

[0008] When the phototransistor Tr1 of the photocoupler (1805) receives light emitted from the light-emitting diode D1, a base current flows and conducts between the collector and emitter. Therefore, the collector voltage of the phototransistor Tr1 becomes the ground voltage, so that the base current of the transistor Tr2 does not flow, the transistor Tr2 turns off, and the collector voltage of the transistor Tr2 becomes "H" (the voltage of the DC power supply VDD).

[0009] Furthermore, when the amplitude of the voltage of the AC power supply (1803) becomes smaller, the forward current flowing through the photodiode D1 becomes smaller, and the amount of light emitted by the photodiode D1 decreases. When the amount of light emitted by the photodiode decreases, the base current stops flowing through the phototransistor Tr1, and the phototransistor Tr1 turns off. Then, a base current flows from the DC power supply VDD to the base of the transistor Tr2 via resistor R2, so the transistor Tr2 turns on and the voltage at the collector of the transistor Tr2 becomes "L" (ground voltage).

[0010] In other words, if the voltage of the AC power supply (1803) when the transistor Tr2 turns on is Vth, then when the absolute value of the voltage of the AC power supply (1803) is smaller than Vth, the transistor Tr2 turns on and the collector voltage of the transistor Tr2 becomes "L" (ground voltage) as shown in Figures 18(c) and 18(d). Also, the period when the transistor Tr2 is on, that is, the period when the collector voltage of the transistor Tr2 is "L", is a period near the zero cross of the voltage waveform of the AC power supply (1803), so this period is called the zero cross period, and the signal indicative of this zero cross period, shown in Figure 18(d), is called the zero cross signal.

[0011] This zero-cross signal is then input to a control unit (1806), which in turn uses a delay means (1810) to delay a heater control signal (FIG. 18(e)) that has been delayed by the delay time calculated by a delay time calculation means (1809) from the falling edge of the zero-cross signal, and outputs the delayed signal to a switch unit (1808). The switch unit (1808) is then turned on using the supplied heater control signal as a trigger, and AC power from the AC power supply (1803) is supplied to a heater (1811).

[0012] A heater control signal (FIG. 18(e)) delayed by a delay time calculated by a delay time calculation means (1809) from the falling edge of the zero-cross signal is output to a switch section (1808). The switch section (1808) is then turned on using the heater control signal as a trigger, and AC power from the AC power supply (1803) is supplied to a heater (1811).

[0013] Here, when the heater control device (1801) is powered on, that is, when the control unit (1806) is powered on, the control unit (1806) starts the delay time calculation operation. Next, it is determined whether a zero cross signal has been detected. This is to determine whether the collector output of the transistor Tr2 has become "L", that is, whether the falling edge of the zero cross signal has been detected. Then, when the falling edge of the zero cross signal is detected, the width of the zero cross signal is measured. That is, the time from the falling edge to the rising edge of the zero cross signal is measured by the zero cross time measuring means (1807). This time from the falling edge to the rising edge of the zero cross signal is the length of the zero cross period, and is therefore called the zero cross time. Then, when the measurement of the zero cross time is finished, the delay time is calculated by the delay time calculating means (1809). On the other hand, if the zero cross time cannot be measured, the detection of the zero cross signal is started again.

[0014] The delay time calculation means (1809) calculates the delay time by multiplying the measured zero cross time by 1 / 2. For example, in the case of the AC voltage waveform shown in FIG. 18(b), the zero cross time measured by the zero cross time measurement means (1807) is multiplied by t a Then, the control unit (1806) calculates the zero cross time t a The delay time t is 1 / 2 the time a Then, the control unit (1806) calculates a delay time t a The heater control signal (FIG. 18(e)) is delayed by 1 / 2 and output to the switch section (1808). As described above, the zero crossing points are detected, and heater control is performed based on them. [Prior art documents] [Patent documents]

[0015] [Patent Document 1] JP 2005-123977 A Summary of the Invention [Problem to be solved by the invention]

[0016] At first glance, the zero-cross detection device in the heater control device of Patent Document 1 appears to accurately detect zero-cross points. However, the voltage that actually passes through the rectifier circuit is not output with an ideal waveform as shown in Figure 18(c) due to factors such as the operating threshold voltage of the diode used for rectification (generally about 0.6V, but varies slightly depending on the product). When the operating threshold voltage of the diode is 0.6V, the rectifier diode does not turn on when the input voltage waveform is in the range of +0.6V to -0.6V, and a flat portion of 0V appears between the peaks of the input voltage waveform of the photocoupler shown in Figure 18(c) (the waveform folded back by full-wave rectification). This results in the t a Therefore, there is a problem that it is difficult to detect the zero-crossing point with high accuracy because it is affected by the threshold voltage of the rectifier diode as well as the operating threshold voltage of the photocoupler. [Means for solving the problem]

[0017] A momentary interruption can be detected by accurately detecting the zero crossing point and determining whether the time when the voltage is 0V exceeds a predetermined time. By accurately detecting the zero crossing point, the period of the AC power supply voltage can be accurately determined, and the presence or absence of a momentary sag can be determined from the integral value of the voltage signal for that period. In order to solve the above problems, a first invention provides a power supply device including: a first photocoupler that outputs a light receiving signal when the acquired AC power signal is positive and does not output a light receiving signal when the acquired AC power signal is negative; a second photocoupler that does not output a light receiving signal when the acquired AC power signal is positive and that outputs a light receiving signal when the acquired AC power signal is negative; a counter for counting a signal width, which is an arbitrary time interval of the AC power signal; a comparative time length information storage unit that stores comparative time length information, which is information indicating a predetermined time length to be compared with non-light receiving time length information, which is information indicating a value counted by the counter during a period when no light receiving signal is acquired from either the first photocoupler or the second photocoupler; a comparison unit that compares the non-light receiving time length information with the comparison time length information; a comparison result output unit that outputs a comparison result when the comparison result is a predetermined comparison result; The present invention provides a power interruption detection device having a

[0018] Furthermore, as a second invention, based on the first invention, there is provided an instantaneous power interruption detection device, in which a comparative time length information holding section holds information indicating a plurality of comparative time length information as the comparative time length information.

[0019] Further, as a third invention, based on either the first or second invention, the first photocoupler is configured to output a signal L when the acquired AC power signal is positive, and to output a signal H when the acquired AC power signal is negative, the second photocoupler is configured to output a signal H in response to a positive AC power signal, and to output a signal L in response to a negative AC power signal; "The time difference between the first timing at which the signal of the second photocoupler switches from L to H and the second timing at which the signal of the first photocoupler switches from H to L in the same timing region where the AC power supply signal inverts from negative to positive" or / and, a time difference acquisition unit that acquires "a time difference between a third timing at which the signal of the second photocoupler switches from H to L and a fourth timing at which the signal of the first photocoupler switches from L to H in the same timing region where the AC power supply signal is inverted positive and negative"; a voltage 0 timing acquisition unit that acquires a timing of voltage 0 of the AC power signal using a correction time length that is half the time length of the acquired time difference; The present invention provides a power interruption detection device further comprising an AC voltage zero-cross detection circuit structure comprising:

[0020] Furthermore, as a fourth invention, based on the third invention, there is provided a power interruption detection device in which the first photocoupler and the second photocoupler have approximately equal ON delay time lengths.

[0021] Furthermore, as a fifth invention, there is provided a power interruption detection device based on either the third or fourth invention, further having a corrected time length acquisition unit that acquires a corrected time length by statistically processing a plurality of acquired time differences.

[0022] Furthermore, as a sixth invention, based on any one of the third to fifth inventions, there is provided a power interruption detection device in which a first photocoupler and a second photocoupler output L when the photocoupler is ON.

[0023] Furthermore, as a seventh invention, based on any one of the third to sixth inventions, there is provided a power interruption detection device having pre-emptive means, wherein a zero-cross timing acquisition unit acquires the zero-cross timing using the timing at which the signal of a first photocoupler rises from L to H just before the zero-cross timing and a correction time length when the AC power supply signal inverts from positive to negative, and acquires the zero-cross timing using the timing at which the signal of a second photocoupler rises from L to H just before the zero-cross timing and a correction time length when the AC power supply signal inverts from negative to positive.

[0024] Furthermore, the present invention provides respective operation methods and respective operation programs corresponding to the instantaneous power interruption detection devices of the first to seventh aspects of the present invention. The respective operation programs may be recorded on a recording medium.

[0025] Furthermore, as an eighth aspect of the present invention, there is provided a power supply device comprising: an AC power signal acquisition unit that acquires an AC power signal; a power supply step-down unit having an isolation transformer for stepping down an AC power supply voltage; an AC full-wave rectification unit that full-wave rectifies the AC voltage stepped down by the power supply step-down unit; An AD conversion section that converts the full-wave rectified waveform into an AD conversion signal; An integration section that integrates the AD converted half wavelength. a comparative value storage unit that stores a comparative value that is a predetermined value for determining whether the integral value of each half wavelength obtained is normal; an abnormality / normality determination unit that compares the obtained integral value of each half wavelength with a stored comparison predetermined value and determines whether the voltage is in an abnormal voltage sag state or a normal state; A power sag detection device having a judgment result output unit that outputs the judgment result, The present invention provides a power dip detection device, characterized in that the AC power signal acquisition unit is shared with any one of the power interruption detection devices according to the first to seventh aspects of the present invention.

[0026] Further, as a ninth invention, based on the eighth invention, a counter of the instantaneous power interruption detection device mounted on any one of the first to seventh inventions is Provided is a power dip detection device in which at least one of an AD conversion unit, an integration unit, a comparison specified value holding unit, an abnormality / normality determination unit, and a determination result output unit are functionally integrated within the same microcomputer.

[0027] Furthermore, as a tenth invention, there is provided a power sag detection device based on the eighth invention, which uses the zero-cross points obtained by the AC voltage zero-cross detection circuit structure of any one of the third to seventh inventions when integrating over a half-wavelength.

[0028] Furthermore, there are also provided operation methods and operation programs corresponding to the power voltage dip detection devices of the eighth to tenth aspects of the present invention. The operation programs may be recorded on a recording medium. Effect of the Invention

[0029] According to the present invention, the period during which an instantaneous interruption occurred can be detected with high accuracy. A voltage sag can be detected with high accuracy. By using an AC voltage zero cross point detection circuit structure, the period during which an instantaneous interruption occurred can be detected with higher accuracy, or a voltage sag can be detected with higher accuracy. By sharing components, a voltage interruption and / or voltage sag detection device can be provided at low cost. [Brief description of the drawings]

[0030] [Figure 1] FIG. 1 is a functional block diagram according to a first embodiment of the present invention. [Diagram 2] 1 is a flowchart according to the first embodiment of the present invention. [Diagram 3] FIG. 1 is a schematic diagram of a hardware configuration according to a first embodiment of the present invention. [Figure 4] FIG. 4 is a signal waveform diagram illustrating the effect of the first embodiment of the present invention. [Diagram 5] FIG. 11 is a functional block diagram according to a second embodiment of the present invention. [Figure 6] FIG. 11 is a schematic diagram of a hardware configuration according to a second embodiment of the present invention. [Figure 7] FIG. 11 is a functional block diagram according to a third embodiment of the present invention. [Figure 8] 11 is a flowchart according to a third embodiment of the present invention. [Figure 9] FIG. 11 is a schematic diagram of a hardware configuration according to a third embodiment of the present invention. [Figure 10] FIG. 11 is a functional block diagram according to a fourth embodiment of the present invention. [Figure 11] 11 is a flowchart according to a fourth embodiment of the present invention. [Figure 12] FIG. 11 is a schematic diagram of a hardware configuration according to a fourth embodiment of the present invention. [Figure 13] FIG. 13 is a functional block diagram according to a fifth embodiment of the present invention. [Figure 14] 11 is a flowchart according to a fifth embodiment of the present invention. [Figure 15] FIG. 13 is a schematic diagram of a hardware configuration according to a fifth embodiment of the present invention. [Figure 16] FIG. 13 is a signal waveform diagram illustrating calculation of a corrected time length according to the fifth embodiment of the present invention. [Figure 17] FIG. 1 is a functional block diagram of a microcomputer according to a first embodiment of the present invention. [Figure 18] Schematic diagram of a circuit configuration of the prior art and waveform diagrams of each point in the circuit [Figure 19] FIG. 13 is a functional block diagram according to an eighth embodiment of the present invention. [Figure 20]FIG. 13 is a schematic diagram of a hardware configuration according to an eighth embodiment of the present invention. [Figure 21] FIG. 13 is a signal waveform diagram illustrating a voltage sag detection according to an eighth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Note that the present invention should not be limited to these embodiments, and can be embodied in various forms without departing from the spirit of the present invention.

[0032] The functional configuration of each embodiment described below can be realized as a combination of hardware and software, which will be described later. Each embodiment described in this specification can be realized not only as an apparatus, but also as an operating method in part or in whole. A part of such an apparatus can be configured as software. Furthermore, software products used to cause a computer to execute such software, and recording media on which such products are fixed, are naturally included in the technical scope of each embodiment described in this specification (the same applies throughout this specification).

[0033] <Embodiment 1> <Embodiment 1 Overview: Mainly Claim 1> Instantaneous interruption device: Basic A first embodiment will be described. A time during which no light receiving signal is obtained from either the first photocoupler or the second photocoupler is compared with a predetermined time length, and when the comparison result is a predetermined result, an output is issued to that effect.

[0034] <Configuration of embodiment 1> The instantaneous power interruption detection device according to an embodiment of the present invention will be described below in the order of its functional configuration, processing flow, and circuit configuration. 1 is a functional block diagram showing an embodiment of an instantaneous power interruption detection device according to the present invention. As shown in the figure, the instantaneous power interruption detection device (0100) is composed of an AC power signal acquisition unit (0101), a first photocoupler (0102), a second photocoupler (0103), a counter (0104), a comparison unit (0105), a comparison time length information storage unit (0106), and a comparison result output unit (0107). The above functional blocks are merely an example for implementing the present invention, and functions may be omitted or new functions may be added as appropriate within the scope that does not contradict the problems to be overcome by the present invention and its effects.

[0035] <Embodiment 1: AC power signal acquisition unit (0101)> The 'acquiring unit for AC power supply signal' (0101) is configured to acquire an AC power supply signal. The intermediate paths between the instantaneous power interruption detection device of the present invention and the power source for which instantaneous interruption is to be detected must be designed with care to prevent a voltage phase shift.

[0036] <Embodiment 1: First Photocoupler (0102)> The "first photocoupler" (0102) is configured to output a light receiving signal when the acquired AC power signal is positive, and not output a light receiving signal when the acquired AC power signal is negative. A photocoupler is generally an element that integrates a light emitting diode, which is a light emitting element, and a phototransistor that is turned on when the light emitting diode emits light, into one package. By using a photocoupler, it is possible to configure an LED section that operates on an AC power supply signal with a reduced voltage using a configuration that does not affect the AC voltage phase, such as a current-limiting resistor, and a circuit that operates on DC, such as a phototransistor, which is a light-receiving element for zero-crossing point detection, and a microcontroller, insulated from each other while preventing any phase shift with the AC power supply.

[0037] <Embodiment 1: Second Photocoupler (0103)> The "second photocoupler" (0103) is configured not to output a light receiving signal when the acquired AC power supply signal is positive, and to output a light receiving signal when the acquired AC power supply signal is negative. In this embodiment, in FIG. 1 and FIG. 3 described later, the first photocoupler (0102) and the second photocoupler are illustrated as an integrated component comprising two photocouplers, but a similar circuit configuration may be achieved by using individual components.

[0038] <Embodiment 1 Counter (0104)> The “counter” (0104) is configured to count a signal width, which is an arbitrary time interval of the AC power signal, and is configured to count the length of the non-light receiving time during which no light receiving signal is acquired from either the first photocoupler or the second photocoupler. The counter function can be configured using the timer / counter function built into a commercially available microcontroller.

[0039] <Embodiment 1: Comparative time length information storage unit (0106)> The "comparison time length information storage unit" (0106) is configured to store comparison time length information, which is information indicating a predetermined time length to be compared with non-light receiving time length information, which is information indicating the value counted by the counter during the period when no light receiving signal is acquired from either the first photocoupler or the second photocoupler. As the comparative time length information, comparative time length information corresponding to the target device is held. Instead of setting and inputting the information in the manufacturing process, a comparative time length information input unit may be further provided, and the comparative time length information may be determined at the installation site of the device, and the information may be input and held.

[0040] <Embodiment 1: Comparison section (0105)> The 'comparison section' (0105) is configured to compare the non-light receiving time length information with the comparison time length information. If a commercially available microcomputer chip that includes the function of the counter (0104) is used, the function can be easily obtained. An example of this is the PIC16F1 series of microcomputer chips manufactured by Microchip Technology. It has the function of counting the pulse width of an external signal as an input signal or the time for one high-low cycle. For example, in a model of the PIC16F1 series, when the system frequency is 32MHz, four cycles are required to execute one instruction, so the timer count frequency is 32MHz / 4=8MHz. One cycle of a 50Hz AC power supply voltage signal is 20msec, and when measured at 8MHz, it becomes 160000 counts per cycle, which exceeds the upper limit of 65536 and cannot be measured with a counter that uses a 16-bit memory area. Therefore, if the signal is divided by 4 using the prescaler function (select from 1, 4, or 8 division), it becomes 40000 counts, which makes it possible to measure it with a 16-bit counter. In addition, in a general commercial single-phase AC 100V power supply (50Hz) in eastern Japan, the time between the photocoupler's ON / OFF threshold voltage of about 0.8V and 0V is about 25μsec, assuming that the AC voltage waveform is an ideal sine wave. When measured with the 8MHz counter, this counts to about 200, and even if divided by 4, it counts to about 50, which is sufficient for measurement. Hereinafter, in this specification, "time," "time length," "time difference," "timing," etc. measured by the counter may not necessarily be in units of time, but may be in units of the counter's count number or count number information derived from the count number, and may be interpreted as such.

[0041] <Embodiment 1: Comparison result output unit (0107)> The 'comparison result output unit' (0107) is configured to output a message to that effect if the comparison result is a predetermined comparison result. It is preferable that the output section outputs an H potential in the normal state, and in the event of an abnormality (when an instantaneous interruption is detected), it becomes the same L potential as when the circuit is OFF or the potential of the open state. This is to ensure that even if some kind of malfunction occurs in the instantaneous interruption detection device itself, or if a situation occurs in which the line between the output of the instantaneous interruption detection device and the device that receives the output result (such as an emergency power switching device) is disconnected, it is possible that the same response as in the event of an instantaneous interruption is taken as an abnormality. If the configuration is such that the H potential is output when an instantaneous interruption is detected, in the event of a malfunction such as a line being disconnected, the instantaneous interruption detection signal will not reach the device, the power switching device will not operate, and life-threatening devices such as artificial heart-lung machines may stop.

[0042] <Processing flow of embodiment 1> 2 is an operation flowchart of the instantaneous power interruption detection device of the embodiment 1. As shown in this figure, the operation method of the instantaneous power interruption detection device of the embodiment includes a comparison time length information storage step (S0201), a comparison step (S0202), and a comparison result output step (S0203). Each step will be described below.

[0043] an AC power signal acquisition unit that acquires an AC power signal; a first photocoupler that outputs a light receiving signal when the acquired AC power signal is positive and does not output a light receiving signal when the acquired AC power signal is negative; a second photocoupler that does not output a light receiving signal when the acquired AC power signal is positive and that outputs a light receiving signal when the acquired AC power signal is negative; a counter for counting a signal width of the AC power signal; In a power interruption detection device comprising: The comparative time length information holding step (S0201) includes, when a light receiving signal is not acquired from either the first photocoupler or the second photocoupler, performing a process of holding information indicating comparative time length information to be compared with a non-light receiving time length in the counter; The AC power signal acquisition step (S0202) performs a process of acquiring an AC power signal, The comparing step (S0203) performs a process of comparing a non-light receiving time length during which no light receiving signal is acquired from either the first photocoupler or the second photocoupler with the comparison time length information to be compared, The comparison result output step (S0204) performs a process of outputting a fact when the comparison result is a predetermined comparison result. This is an operating method for causing the power interruption detection device to execute a series of processes.

[0044] <Hardware configuration of embodiment 1> The hardware configuration of the instantaneous power interruption detection device in this embodiment will be described with reference to the drawings. Fig. 3 is a schematic diagram for explaining the circuit configuration of the instantaneous power interruption detection device (0300) in embodiment 1. It is composed of an AC power supply (0301), a current limiting resistor (0302), a two-circuit photocoupler (0303), a microcomputer (0304), a counter (0305), a zero-cross measurement calculation (0306), a comparison judgment (0307), a comparison time length information storage (0308), a zero-cross detection output (0309), a comparison result output (0310), etc.

[0045] The microcomputer used is a commercially available one, but in this example, it is assumed to use a product with a built-in counter and pulse generation function, such as the PIC16F1 series mentioned above. The configuration of the microcomputer will be explained using Figure 17. The microcomputer (1700) is composed of a control circuit (1701), an arithmetic circuit (1702), a register (1703) made of RAM used for temporary storage, a data memory (1704) made of RAM for storing data, a clock generator (1705) for executing various operations of the microcomputer, a program memory (1706) made of non-volatile memory for storing various programs, a port control (1707) for controlling various ports, a timer based on the pulses of the clock generator (1705) built into the microcomputer or an external crystal oscillator, a counter / timer (1708) having a counter function that starts counting when triggered by an external input, a serial communication (1709) for communicating with the outside, and an AD / DA converter (1710). A program written in a high-level language such as C or assembler using program development software on a separate PC is written to the microcomputer using a dedicated tool. The written program is stored in the program memory (1706) in the microcomputer. The program memory (1706) is a type of memory that retains records even without power supply and is rewritable, such as an EEPROM or flash memory. The programs stored include a program that takes in the start or stop timing of acquisition of the light receiving signal output from the photocoupler as a trigger and operates the counter / timer (1708), a program that compares the length of non-light receiving time during which no light receiving signal is obtained from both the first and second photocouplers with a predetermined time, and a program that outputs when the comparison result is the predetermined comparison result.

[0046] The counter / timer (1709) will be described using the comparison time length as an example of the comparison time length information (which may be a time unit, a clock count, or a natural number multiple). The counter / timer (1708) senses the timing of the start or stop of acquisition of the light receiving signal output from the photocoupler, and acquires the count as a trigger. It acquires a reference clock or its divided clock signal, and counts up the corresponding register. The comparison program compares whether the comparison time length has been reached during the count-up, and if the comparison time length has been reached, outputs that fact. If it detects the acquisition or stop of the light receiving signal again before the comparison time length is reached, it performs an operation of acquiring the count. In normal operation, the non-light receiving time length during which the light receiving signal cannot be acquired from both the first photocoupler and the second photocoupler is less than 100 μs. For example, if the comparison time length is set to 3 ms (24,000 counts when the 8 MHz counter is used), the non-light receiving time length does not reach the comparison time length even when it is compared with the comparison time length under normal circumstances, and it is not determined to be an instantaneous interruption. If a momentary interruption occurs, the length of non-light receiving time is compared with a comparison time length (e.g., 3 ms), and if it reaches or exceeds the comparison time length, it is compared with the comparison time length and determined to be a momentary interruption, and detection information of a momentary interruption is output. The purpose of the present invention is not to be violated even if the counter and pulse generation functions are external components to the microcontroller. It is preferable to integrate them in one microcontroller, because it is cheaper, smaller, and more convenient.

[0047] The detection of a momentary interruption will be explained with reference to Fig. 4, which shows waveforms at points a, b, and c in the circuit of Fig. 3, which is one of the configuration examples of this embodiment. In the signal waveform at point a at the top, the dotted line shows the normal waveform. The solid line shows a schematic representation of the waveform when a momentary interruption occurs. The part indicated by the arrow showing the momentary interruption period t is the period when the voltage became 0V due to the momentary interruption. Generally, a CPU used in a PC is provided with a circuit called a RESET circuit, which detects when the DC power supply drops in voltage due to a momentary interruption and takes measures to prepare for momentary interruptions and drops. However, the RESET circuit's detection of momentary interruptions is slow, and problems often occur. Therefore, a method that can detect momentary interruptions more quickly is needed in addition to the RESET circuit. In electronic devices and electrical devices such as PCs, even if a power outage occurs, the total circuit voltage does not immediately become 0V at the time of the power outage due to the power supply discharged from the electric capacity of the internal circuitry of the device, but the voltage drops over a period of approximately several tens of milliseconds to 100 milliseconds. Before the voltage falls below the voltage required for CPU operation, it is necessary to detect momentary interruptions at about half a cycle of the AC signal (10 milliseconds at 50 Hz) in order to take measures to prepare for a power outage such as saving data. Lamps for exposure machines in semiconductor manufacturing lines also go out when a voltage drop of 20% or more continues for about 50 to 100 milliseconds, and it takes a long time for them to be turned on again and stabilize. In particular, lamps for production lines must maintain a constant illuminance in order to stabilize the processing accuracy and produce good products. Therefore, it is necessary to make a judgment within about 10 milliseconds. Also, in AC power switchers (devices that switch from a power source with a problem to a normal power source) in hospitals and other facilities, it is considered better to detect the power interruption earlier and send a signal within about 4 ms in order to start up and stabilize the power supply after switching. Therefore, it is also necessary to detect momentary interruptions within about 3 ms. These two types of time are examples of what can be subject to momentary interruption detection.

[0048] In the circuit configuration of FIG. 3, at point b in FIG. 4, when the AC power supply voltage signal is positive, the first photocoupler turns ON, outputs a light receiving signal, and becomes an L potential, and at point c, when the AC power supply voltage signal is positive, the second photocoupler turns OFF, does not output a light receiving signal, and becomes an H potential. As shown in the signal at point a in Figure 4, if a momentary interruption occurs halfway through the first positive peak and is restored halfway through the negative peak, the first photocoupler is in the ON state at the start of the momentary interruption period t, but when the voltage drops below the threshold voltage, it turns OFF, no output signal is output, and the potential changes from L to H. Since the AC power supply potential of the second photocoupler was positive at the time the momentary interruption occurred, it was originally in the OFF state and did not output a received light signal, and point c was at H potential; even if the voltage becomes 0V due to the momentary interruption, it does not exceed the threshold voltage and so the OFF state continues, and point c remains at H potential. Therefore, during the momentary interruption period, neither the first nor second photocoupler outputs a received light signal, and points b and c are both at H potential. When the momentary interruption ends near the end of the negative period of the AC power supply voltage signal (signal at point a in Figure 4), the second photocoupler turns ON, the light receiving signal is output, and point c goes to L potential, but after a short time the AC power supply voltage signal changes from negative to positive, the second photocoupler turns OFF, the light receiving signal is no longer output, and point c goes to H potential. Immediately after the end of the momentary blackout period in Figure 4, the first photocoupler is OFF because the AC power supply voltage signal is negative, no light receiving signal is output, and point b remains at H potential. Note that it is also possible to configure so that the potentials of the corresponding points b and c become H potential instead of L potential depending on the light receiving signal output when the first and second photocouplers are ON. In that case, an extra transistor or the like is required for each photocoupler, as in the conventional technology shown in Figure 18.

[0049] Under normal conditions, both the first and second photocouplers are at H potential only for a period of about 50 to 100 μs, such as the difference between the first and second timings, or the difference between the third and fourth timings. Therefore, the period during which the output signals of the two photocouplers are at H potential is measured by the counter of the microcontroller and judged using a predetermined time, for example, the above-mentioned 3 ms or 10 ms, as a reference. If the predetermined time is reached or exceeded, it is judged to be an instantaneous interruption, and an instantaneous interruption detection signal is output. An example of an instantaneous interruption detection output signal is shown at the bottom of Figure 4. The period during which both photocouplers do not output a light receiving signal is output as an OFF potential when the circuit is OFF (it is preferable to keep the L potential at the OFF potential). This is to allow the same measures to be taken as for an instantaneous interruption even in cases of failure due to causes other than instantaneous interruption. If a commercially available microcontroller, such as the above-mentioned PIC16F1 series, is used, a counter function is built in and it can be easily configured.

[0050] With the zero-crossing point detection method using a full-wave rectifier and one photocoupler, there is a concern that the detection of the zero-crossing point that could be the start of a momentary interruption period may be off due to a non-ideal waveform after rectification, but by using two photocouplers to detect positive / negative and negative / positive changes based on the unrectified AC power supply voltage waveform, the zero-crossing point can be calculated with high precision. Since the start and end points of the voltage reaching 0V can be obtained, it is also possible to calculate the amount of heat that could not be provided to a heating lamp, etc., and control it to compensate for it after the momentary interruption is restored.

[0051] <Embodiment 2: Mainly Claim 2> Having multiple comparative time length information <Overview of the second embodiment> A description will now be given of embodiment 2. This embodiment is characterized in that a comparative time length information storage unit stores a plurality of pieces of comparative time length information.

[0052] <Configuration of the Second Embodiment> The instantaneous power interruption detection device according to an embodiment of the present invention will be described below in the order of its functional configuration, processing flow, and circuit configuration. 5 is a functional block diagram of the second embodiment based on the first embodiment. A comparative duration information storage unit (0506) is configured to store a plurality of comparative duration information. Since the components other than the comparative duration information storage unit (0506) are the same as those of the first embodiment, the description thereof will be omitted.

[0053] <Embodiment 2: Comparative time length information storage unit (0506)> The 'storage unit for comparative time length information' (0506) is configured to store information indicating a plurality of pieces of comparative time length information as the comparative time length information. As the plurality of pieces of comparative time length information, for example, there are two kinds of comparative time length information, 3 ms required for switching to an emergency power source or the like, and 10 ms required for data evacuation of a CPU of a PC or the like, as described above, but the types (number) of comparative time length information to be held are not limited to two, and may be increased depending on the device configuration and purpose. The comparison unit (0505) compares the obtained non-light receiving time length with a plurality of pieces of comparative time length information (for example, comparative time length information 1, comparative time length information 2, etc.), and outputs a predetermined comparison result (for example, reaching or exceeding the comparative time length information) when the result is a predetermined comparison result. Although the comparison unit (0505) is shown as one in FIG. 5, a plurality of comparison units such as comparison unit 1 and comparison unit 2 may be provided according to the number of the plurality of pieces of comparative time length information to be held. Furthermore, a plurality of comparison result output units such as comparison result output unit 1, comparison result output unit 2, etc. corresponding to the number of the plurality of pieces of comparative time length information to be held may be provided. Each comparison unit may compare one piece of comparative time length information, or each comparison unit may compare multiple pieces of comparative time length information, or a combination thereof may be used.

[0054] <Processing flow of embodiment 2> The process flow of the second embodiment will be described based on the first embodiment by utilizing the operation flowchart of the instantaneous power interruption detection device in Fig. 2. The difference is that the comparative time length information holding step holds a plurality of pieces of comparative time length information, and the comparison unit performs a process of comparing the plurality of pieces of comparative time length information with the non-light receiving time length.

[0055] an AC power signal acquisition unit that acquires an AC power signal; a first photocoupler that outputs a light receiving signal when the acquired AC power signal is positive and does not output a light receiving signal when the acquired AC power signal is negative; a second photocoupler that does not output a light receiving signal when the acquired AC power signal is positive and that outputs a light receiving signal when the acquired AC power signal is negative; a counter for counting a signal width of the AC power signal; In a power interruption detection device comprising: The comparative time length information holding step (S0201) includes, when a light receiving signal is not acquired from either the first photocoupler or the second photocoupler, performing a process of holding a plurality of pieces of information indicating comparative time length information to be compared with a non-light receiving time length in the counter; The AC power signal acquisition step (S0202) performs a process of acquiring an AC power signal, The comparing step (S0203) performs a process of comparing a non-light receiving time length during which no light receiving signal is acquired from either the first photocoupler or the second photocoupler with the plurality of pieces of comparison time length information to be compared; The comparison result output step (S0204) performs a process of outputting a fact when the comparison result is a predetermined comparison result. This is an operating method for causing the power interruption detection device to execute a series of processes.

[0056] <Hardware configuration of embodiment 2> The hardware configuration of the instantaneous power interruption detection device in this embodiment will be described with reference to the drawings. Fig. 6 is a schematic diagram for explaining the circuit configuration of the instantaneous power interruption detection device (0600) in embodiment 2. It is composed of an AC power supply (0601), a current limiting resistor (0602), a two-circuit photocoupler (0603), a microcomputer (0604), a counter (0605), a comparison time length information holder (0606), a comparison judgment 1 (0607), a comparison result output 1 (0608), a comparison judgment 2 (0609), a comparison result output 2 (0610), etc.

[0057] The difference is that a plurality of pieces of comparison time length information are held in the comparison time length information hold (0606), and comparison judgment 1 (0607), comparison judgment 2 (0609), comparison result output 1 (0608), and comparison result output 2 (0610) are provided according to the number of comparison time length information held. This is the same as in the first embodiment except that comparison judgments 1 and 2 and comparison result outputs 1 and 2 function exclusively for the corresponding comparison time length information. Depending on the commercially available microcomputer used, two or more pieces of comparison time length information may be held. Also, a plurality of pieces of comparison time length information may be stored, and one "comparison judgment" may be used to judge which of the plurality of pieces of comparison time length information has a predetermined comparison result, and if the comparison result is the predetermined comparison result, the fact may be output from one "comparison result output". For example, if the comparison time length information is 3 ms and 10 ms, a comparison judgment may be made as to whether the acquired non-light receiving time length reaches or exceeds either of the pieces of comparison time length information, and if it exceeds 3 ms, a DC-5V output may be output, if it exceeds 10 ms, a DC+5V output may be output, and otherwise a DC0V output may be output. The output terminal may be divided into two and output. Also, one comparison unit may be provided with a plurality of comparison result outputs, and output from a plurality of output terminals. As long as a plurality of predetermined time lengths are stored and a comparison result is output in response, the configuration of the comparison unit and comparison result output unit is not limited to the configuration of FIG. 6. The output voltage value at the time of instantaneous interruption detection is not limited to the above value. It may be a form in which DC0V is output at the time of instantaneous interruption detection. By storing multiple predetermined times, a single power interruption detection device can determine multiple durations of the interruption.

[0058] <Embodiment 3: Mainly Claim 3> Having a zero-cross detection circuit structure <Overview of the Third Embodiment> A third embodiment will be described. Based on the first or second embodiment, the third embodiment is characterized by further comprising an AC voltage zero-cross detection circuit structure. By providing the AC voltage zero-cross detection circuit structure, the zero-cross point (voltage 0V) can be obtained and captured with high accuracy, and the start and end points of the instantaneous interruption can be obtained more accurately. In other words, the duration of the instantaneous interruption can be obtained accurately. For heating lamps, the energy that was scheduled to be supplied during the instantaneous interruption can be calculated separately and compensated for.

[0059] <Configuration of embodiment 3> The instantaneous power interruption detection device according to an embodiment of the present invention will be described below in the order of its functional configuration, processing flow, and circuit configuration. 7 is a functional block diagram showing an embodiment of the instantaneous power interruption detection device of this embodiment. As shown in the figure, the instantaneous power interruption detection device (0700) is composed of an AC voltage zero-cross detection circuit structure (0708) composed of an AC power signal acquisition unit (0701), a first photocoupler (0702), a second photocoupler (0703), a time difference acquisition unit (0709), and a zero-cross timing acquisition unit (0710), a counter (0704), a comparison unit (0705), a comparison time length information storage unit (0706), and a comparison result output unit (0707). The above functional blocks are merely an example for implementing the present invention, and functions may be omitted or new functions may be added as appropriate within the scope that does not contradict the problems to be overcome by the present invention and its effects.

[0060] <Embodiment 3: AC power signal acquisition unit (0701)> The 'acquiring unit for AC power supply signal' (0701) is configured to acquire an AC power supply signal.

[0061] <Embodiment 3: First photocoupler (0702)> The "first photocoupler" (0702) is configured to output a signal L when the acquired AC power signal is positive, and to output a signal H when the acquired AC power signal is negative. A photocoupler is generally an element that integrates a light-emitting diode, which is a light-emitting element, and a phototransistor that is turned on in response to light emitted by the light-emitting diode, into one package. By using a photocoupler, it is possible to configure an LED section that operates on an AC power supply signal with a reduced voltage using a configuration that does not affect the AC voltage phase, such as a current-limiting resistor, and a circuit that operates on DC, such as a phototransistor, which is a light-receiving element for zero-crossing point detection, and a microcontroller, insulated from each other while preventing any phase shift with the AC power supply.

[0062] <Embodiment 3: Second Photocoupler (0703)> The "second photocoupler" (0703) is configured to output a signal H in response to the acquired AC power signal being positive, and to output a signal L in response to the acquired AC power signal being negative. In this embodiment, in FIG. 10 described later, the first photocoupler (1003a) and the second photocoupler (1003b) are illustrated as an integrated component called a dual-circuit photocoupler (1003), but a similar circuit configuration may also be achieved using each of them as a stand-alone component.

[0063] <Embodiment 3: Time difference acquisition unit (0709)> The "time difference acquisition unit" (0709) is configured to acquire "the time difference between the first timing at which the signal of the second photocoupler switches from L to H and the second timing at which the signal of the first photocoupler switches from H to L in the same timing region where the AC power supply signal inverts from negative to positive" and / or "the time difference between the third timing at which the signal of the second photocoupler switches from H to L and the fourth timing at which the signal of the first photocoupler switches from L to H in the same timing region where the AC power supply signal inverts from positive to negative." As shown in the schematic circuit diagram of FIG. 10 described later, the function can be easily obtained by using a commercially available microcomputer chip including a counter function (for example, the PIC16F1 series microcomputer chips manufactured by Microchip Technology).

[0064] When the AC power supply signal reverses between positive and negative, the counter of the microcomputer detects the fourth timing, which is the rising edge of the pulse at which the signal of the first photocoupler changes from L to H, as a trigger and starts counting. The counter of the microcomputer stops counting the pulse width when it detects the third timing, which is the falling edge of the pulse at which the second photocoupler changes from H to L, later. The time difference acquisition unit (0709) obtains the number of counts between the third timing and the fourth timing. Conversely, when the AC power supply signal is inverted from negative to positive, the counter of the microcomputer detects and starts counting the first timing, which is the rising edge of the pulse at which the signal of the second photocoupler changes from L to H, as a trigger, and stops counting the pulse width when the counter of the microcomputer detects the second timing, which is the falling edge of the pulse at which the signal of the first photocoupler changes from H to L. The time difference acquisition unit (0709) obtains the number of counts between the first timing and the second timing. The time difference acquisition unit (0709) may convert the counter clock frequency and frequency division value when the counter counts and the obtained count number into time and transmit them to the zero cross timing acquisition unit (0710), or may transmit them as count numbers. Transmitting the count numbers as they are can eliminate the processing time for multiplication and memory storage. Hereinafter, in this specification, "time," "time difference," "timing," etc. measured by the counter may not necessarily be in units of time, but may be interpreted as units of the counter count number, and may be interpreted alternatively.

[0065] <Third embodiment: Zero cross timing acquisition unit (0710)> The "zero cross timing acquisition unit" (0710) is configured to acquire the timing of zero voltage of the AC power signal using a correction time length that is half the time length of the acquired time difference information. The time difference information, which is the rise and fall timing difference between the pulses of the first photocoupler and the second photocoupler acquired by the time difference acquisition unit, is multiplied by 1 / 2 and used to correct the zero cross point of the next half cycle of the AC power signal. As in the embodiment described later, when the AC power signal is inverted in polarity, 1 / 2 of the time difference is added to the fourth timing when the signal of the first photocoupler changes from L to H, to correct and output the zero cross pulse. Even if the zero cross point is shifted due to a cause such as a variation in the power supply frequency caused by a change in power demand, the correction can be reflected in the next half cycle. In addition, due to the operating threshold voltage of the built-in light-emitting diode and the operating threshold voltage of the phototransistor that receives light, the photocoupler does not immediately start outputting a light receiving signal even when a voltage is applied from 0V, but starts outputting a light receiving signal when it reaches about 0.8V depending on the product. Therefore, the first photocoupler and the second photocoupler have an ON delay time until they start outputting a light receiving signal even when the AC voltage starts to increase or decrease from 0V. In particular, when the first photocoupler and the second photocoupler are configured as a single combination, the ON delay times of both photocouplers may differ. The ON delay times of both photocouplers are measured before use of the device, and a photocoupler ON delay time ratio information storage unit is provided that stores photocoupler ON delay time ratio information, which is information indicating the ratio of the ON delay time lengths of the two photocouplers obtained (for example, a ratio of m:n or 1:k), and the obtained time length is divided based on the photocoupler ON delay time ratio information to obtain a correction time length. In the description of the third embodiment and subsequent embodiments in this specification, when the obtained time length is multiplied by 1 / 2, it can be read as being distributed to a ratio such as m:n.

[0066] The method of outputting the zero-cross pulse depends on the specifications of the microcomputer used, but for example, as mentioned above, only the time difference between the third timing and the fourth timing or the time difference between the first timing and the second timing is measured by a counter, and the correction time length is held by multiplying the counter value by 1 / 2. There is also a method in which the signal change of the photocoupler output at the first timing or the fourth timing, approximately half a wavelength ahead of the AC power supply voltage signal, is used as a trigger to change the zero-cross pulse signal potential when the count value equivalent to the held correction time length has advanced. In addition, monitoring of the reference timer count value is started after the device is started or at an appropriate timing after the device is started, the count value of the change point of the photocoupler output (from the first timing to the fourth timing) is recorded, and the difference is multiplied by 1 / 2 to obtain the correction time length. There is also a method in which the signal change of the photocoupler output at the first timing or the fourth timing, approximately half a wavelength ahead of the AC power supply voltage signal, is used as a trigger to change the zero-cross pulse signal potential when the count value equivalent to the held correction time length has advanced. If the AC power supply signal is positive at the start of detection, a DC positive predetermined voltage (e.g., +3V) is output, and when a correction time length that is half the time length of the time difference information acquired by the zero-cross timing acquisition unit is used for correction after a half cycle, the zero-cross detection can be output by changing the predetermined DC voltage being output from positive (H potential) to 0V (L potential) at a predetermined timing. There is also a method of outputting a short rectangular pulse at a predetermined timing so that the rising edge of the pulse is the zero-cross point, but in this specification, a method of switching the potential of the zero-cross pulse at a predetermined timing will be described.

[0067] <Embodiment 3 Counter (0704)> The "counter" (0704) is configured to count the signal width of the AC power signal, and is configured to count the length of time during which no light reception signal is obtained from either the first or second photocoupler. In a normal state, the first and second photocouplers alternate between ON and OFF across the zero cross point, and the counter (0704) counts the period during which both are OFF and no light reception signal is obtained.

[0068] <Embodiment 3 Comparison section (0705)> The "comparison unit" (0705) is configured to compare the non-light receiving time length during which no light receiving signal is acquired from either the first or second photocoupler with the comparison time length information to be compared. Although a description thereof will be omitted since it is similar to the first or second embodiment, the comparison unit (0705) refers to the comparison time length information to be compared that is stored in the comparison time length information storage unit (0706) and compares it with the non-light receiving time length measured by the counter (0704). For example, it judges whether the comparison time length information is reached or exceeded. The comparison result output unit (0707) is the same as in the first or second embodiment, so a description thereof will be omitted.

[0069] <Processing flow of embodiment 3>

[0070] <Processing flow of embodiment 3> 8 is an operation flowchart of the instantaneous power interruption detection device of embodiment 3. As shown in this figure, the operation method of the instantaneous power interruption detection device of embodiment 3 includes a comparison time length information storage step (S0801), an AC power signal acquisition step (S0802), a fourth timing acquisition step (S0803a), a third timing acquisition step (S0803b), a first timing acquisition step (S0803c), a second timing acquisition step (S0803d), a time difference acquisition step (S0804), a zero cross timing acquisition step (S0805), a comparison step (S0806), and a comparison result output step (S0807). Each step will be described below.

[0071] Here, at the timing when the AC power supply waveform changes from positive to negative, The comparative time length information holding step (S0801) performs a process of holding information indicating a comparative time length to be compared with information indicating a non-light receiving time length counted by the counter when a light receiving signal is not acquired from either the first photocoupler or the second photocoupler, The AC power signal acquisition step (S0802) performs a process of acquiring an AC power signal, The fourth timing acquisition step (S0803a) performs a process of acquiring a fourth timing, which is the timing at which the AC power waveform changes from positive to negative, which is the same as a timing described later, and is the timing at which the signal rises from L to H, from a first photocoupler that outputs a signal L when the acquired AC power signal is positive and outputs a signal H when the acquired AC power signal is negative; The third timing acquisition step (S0803b) performs a process of acquiring a third timing, which is the timing at which the signal falls from H to L when the AC power waveform changes from positive to negative, from a second photocoupler that outputs a signal H when the acquired AC power signal is positive and outputs a signal L when the acquired AC power signal is negative, and is the same timing as the timing described above; The time difference acquisition step (S0804) includes a process of acquiring time difference information that is information indicating a time difference between the fourth timing and the third timing; The zero cross timing acquisition step (S0805) performs a process of acquiring zero cross timings of the AC power supply by using the time difference information and any third timing or any fourth timing subsequent to the third timing and the fourth timing, The comparing step (S0806) performs a process of comparing a non-light receiving time length during which no light receiving signal is acquired from either the first photocoupler or the second photocoupler with the comparison time length information to be compared, The comparison result output step (S0807) performs processing to output a fact that the comparison result is a predetermined comparison result.

[0072] Here, at the timing when the AC power supply waveform changes from negative to positive, The comparative time length information holding step (S0801) performs a process of holding information indicating a comparative time length to be compared with information indicating a non-light receiving time length counted by the counter when a light receiving signal is not acquired from either the first photocoupler or the second photocoupler, The AC power signal acquisition step (S0802) performs a process of acquiring an AC power signal, In the first timing acquisition step (S0803c), a process is performed to acquire a first timing, which is a timing at which the AC power waveform changes from negative to positive, which is the same as a timing described later, and is a timing at which the signal rises from L to H, from a second photocoupler that outputs a signal H when the acquired AC power signal is positive and outputs a signal L when the acquired AC power signal is negative; In the second timing acquisition step (S0803d), a process is performed to acquire a second timing, which is the timing at which the signal falls from H to L when the AC power waveform changes from negative to positive, from a first photocoupler that outputs a signal L when the acquired AC power signal is positive and outputs a signal H when the acquired AC power signal is negative, and which is the same timing as the timing described above, when the AC power waveform changes from negative to positive; In the time difference acquisition step (S0804), a process is performed to acquire time difference information which is information indicating a time difference between the first timing and the second timing; In a zero cross timing acquisition step (S0805), a process of acquiring a zero cross timing of the AC power supply is performed using the time difference information and an arbitrary first timing or an arbitrary second timing subsequent to the first timing and the second timing, The comparing step (S0806) performs a process of comparing a non-light receiving time length during which no light receiving signal is acquired from either the first photocoupler or the second photocoupler with the comparison time length information to be compared, The comparison result output step (S0807) performs processing to output a fact that the comparison result is a predetermined comparison result. After the time difference acquisition step (S0804), if the acquired time difference information is within a normal range or is a value that can be clearly regarded as abnormal, such as a value equivalent to a half wavelength, it can be configured to determine that the information is abnormal and not use the calculated time difference information. In that case, the previously calculated time difference information can be used again, or a previously calculated ideal value can be used as the provisional correction length. This is an operating method for causing the power interruption detection device to execute a series of processes.

[0073] <Hardware configuration of embodiment 3> The hardware configuration of the instantaneous power interruption detection device in this embodiment will be described with reference to the drawings. Fig. 9 is a schematic diagram for explaining the circuit configuration of the instantaneous power interruption detection device (0900) in embodiment 3. It is composed of an AC power supply (0901), a current limiting resistor (0902), a two-circuit photocoupler (0903), a microcomputer (0904), a counter (0905), a comparison time length information holder (0906), a comparison decision 1 (0907), a comparison result output 1 (0908), a comparison decision 2 (0909), a comparison result output 2 (0910), a zero-cross measurement calculation (0911), a zero-cross detection output (0912), etc. A signal is obtained from the AC power supply (0901) to detect the zero crossing point, and a momentary interruption in the power supply from the AC power supply (0901) is judged based on the detected zero crossing point. It is preferable to configure the circuit system so that there is no phase shift between the AC power supply signal for measuring the zero crossing point used for detection and the comparison result outputs 1 and 2. This is because if the comparison result is output later than the specified time information, the momentary interruption detection will not be effective. The two-circuit photocoupler (0903) may be configured using a photocoupler for each circuit.

[0074] The microcontroller used is a commercially available one, but we assume that it has a built-in counter and a pulse generation function, like the PIC16F1 series mentioned above. The configuration of the microcontroller will be explained using Figure 17. The microcontroller (1700) is composed of a control circuit (1701), an arithmetic circuit (1702), a register (1703) made of RAM used for temporary storage, a data memory (1704) made of RAM for storing data, a clock generator (1705) for executing various operations of the microcontroller, a program memory (1706) made of non-volatile memory for storing various programs, a port control (1707) for controlling various ports, a timer based on pulses from the built-in clock or an external crystal oscillator, a counter / timer (1708) with a counter function that starts counting when triggered by an external input, a serial communication (1709) for communicating with the outside, and an AD / DA converter (1710). Programs written in high-level languages ​​such as C or assembler using program development software on a separate PC are written to the microcontroller using a dedicated tool. The programs to be written are stored in the program memory (1706) in the microcontroller. The program memory (1706) is a type of memory that retains records even without power and is rewritable, such as an EEPROM or flash memory. The programs stored in the program memory (1706) include a program that uses the rising and falling timing of the photocoupler output signal as a trigger to input the signal into the counter / timer (1708) to operate the counter for zero-cross detection, and a program that generates a zero-cross pulse based on the count number, which is the obtained time difference information. The output signal from the photocoupler is input to the counter / timer (1708), which detects the timing of a rising or falling edge and starts counting as a trigger. The number of pulses of the reference clock is counted, and the corresponding register is counted up. If another rising or falling edge is detected, the counting stops. The calculation unit multiplies the obtained count by 1 / 2 and stores the result in data memory. The count before multiplying by 2 is compared with the comparative time length information held in memory (for example, a count of 3 ms or the equivalent of 3 ms), and if it reaches or exceeds the comparative time length information, it is compared with the comparative time length information and determined to be a momentary interruption, and detection information of a momentary interruption is output. The purpose of the present invention is not to be violated even if the counter and pulse generation functions are external components to the microcontroller. It is preferable to integrate them in one microcontroller, because it is cheaper, smaller, and more convenient.

[0075] A method of finding the zero cross point will be explained using FIG. 4. In FIG. 4, a, b, and c also show the signal waveforms at a, b, and c in the circuit of FIG. 9. The horizontal axis represents time, and the vertical axis represents voltage. The top point a shows the power signal voltage waveform, which is a sine wave at point a in FIG. 9, that is, the AC power supply (0901). When point a, which represents the voltage signal obtained by branching so as to have the same phase as the AC power supply supplied to the target device that the power interruption detection device (0900) is trying to detect, is on the positive side, a current flows through the first photocoupler (0903a) in the two-circuit photocoupler (0903), and the light-emitting diode starts to light up. Focusing on the upward convex part on the right side of the sine wave waveform at the top of FIG. 4, the horizontal straight lines arranged to sandwich the zero cross (the intersection of the voltage 0V and the voltage signal) in the figure represent the ON / OFF threshold voltages of the first and second photocouplers. When the power supply signal (point a) is positive, the light-emitting diode in the first photocoupler (0903a) lights up and the phototransistor receives the light and turns ON, and point b is connected to 0V of the circuit via the phototransistor, resulting in an L potential. Conversely, when the power supply signal (point a) becomes negative, the light-emitting diode in the first photocoupler (0903a) does not light up and the phototransistor turns OFF, so point b is supplied with a positive direct current Vcc potential (H potential) via resistor R, resulting in an H potential. When the power supply signal (point a) is negative, the light-emitting diode in the second photocoupler (0903b) lights up and the phototransistor turns ON, so point c changes from an H potential to an L potential. It is possible to configure the circuit so that when both photocouplers are ON, the potentials of points b and c become H potential instead of L potential, but this would increase the number of components such as transistors as shown in Figure 14, which is a technology from Reference 1.

[0076] The first photocoupler (0903a) and the second photocoupler (0903b) alternately turn on depending on whether the AC waveform of the power supply is positive or negative, and the potentials at points b and c change in a square wave shape. Figure 4 shows the first timing to the fourth timing, which are the switching timings between the H potential and the L potential of the first photocoupler output and the second photocoupler output described above. The counter (0905) measures the time between the rising and falling edges of the two square wave pulses, "first timing - second timing" or "fourth timing - third timing", and calculates the timing difference. Due to the threshold voltage at which the light-emitting diode turns on and the threshold voltage at which the phototransistor turns on, when the power supply signal switches from negative to positive and from positive to negative, it does not turn on / off correctly at a voltage of 0V. Therefore, when comparing the pulse waveforms at points b and c near the point where the power supply voltage becomes 0V, a time difference occurs between the rising and falling edges. The time difference may be in the form of a count value in a counter. In the following specification, the "time," "time difference," "timing," and "time length" measured by a counter may not be in units of time, but may be in units of counter counts or information derived from the count unit (for example, an integer multiple of the count number), and can be interpreted as such. When the count unit or information derived from the count number is not divisible when processing such as multiplying by 1 / 2, either rounding up or rounding down the fraction may be adopted. It is preferable to determine in advance how to handle the case where it is not divisible.

[0077] The obtained time difference is multiplied by 1 / 2 in the zero cross measurement calculation (0911), and the value is used to correct the rise and fall timing of the zero cross pulse half a wavelength ahead, and is output as the zero cross detection output (0912). Applying correction to the zero crossing point half a wavelength away means, for example, finding half the time difference when the power supply signal waveform changes from negative to positive, and then using that value to correct the zero crossing point half a wavelength away where the power supply signal waveform next changes from positive to negative. In addition, the system can be configured to accumulate and hold half the value of the calculated time difference, and if the value just calculated is clearly abnormal (for example, a time difference of half a wavelength), it can be configured not to use the half value of the time difference that showed the abnormal value, but to use a value that is preset as a provisional correction time length or the previous value instead of using it for correction. It is equipped with an AC power supply voltage zero-cross detection circuit structure, and can output from the zero-cross detection output (0912) to an external switch section or the like. The ON / OFF timing of the switch section, which is made up of switching elements such as thyristors and optical MOS-FET relays, can be controlled using a zero-cross pulse signal. By turning the switch section ON / OFF at the zero-cross point (the rising or falling edge of the zero-cross pulse), it is possible to suppress noise generation and inrush current generation in the output, and also to make the starting point of control more accurate in output adjustment by phase control.

[0078] The zero crossing point can be calculated more accurately, and in addition to detecting momentary interruptions, a zero crossing detection output can be output.

[0079] <Embodiment 4: Mainly Claim 4> The characteristics of the two photocouplers are approximately equal <Overview of embodiment 4> A fourth embodiment will be described. Based on the third embodiment, the first photocoupler and the second photocoupler are configured to have substantially equal ON delay time lengths.

[0080] <Configuration of embodiment 4> The following describes the functional configuration, processing flow, and circuit configuration of the power interruption detection device according to an embodiment of the present invention, based on embodiment 3. Since the configuration other than the first and second photocouplers is the same as in the other embodiments, only the first and second photocouplers will be described. Due to the threshold voltage for the light emitting diode constituting the photocoupler to emit light and the threshold voltage for the photodiode, which is the light receiving element, to turn on, a delay time occurs from the zero crossing point until the photocoupler turns on and outputs a light receiving signal due to the time difference from 0V to the operating threshold voltage. Conversely, when the voltage gradually drops from a voltage exceeding the operating threshold toward 0V, the photocoupler turns off when it reaches the threshold voltage just before 0V (zero crossing point), so the photocoupler switches from ON to OFF ahead of the zero crossing point. A feature of the fourth embodiment is that these ON delay time lengths are approximately equal between the two photocouplers. The above functional blocks are merely an example for implementing the present invention, and functions may be omitted or new functions may be added as appropriate within the scope that does not contradict the problems to be overcome by the present invention and its effects.

[0081] The functional configuration of this embodiment will be described with reference to FIG. <Embodiment 4: First photocoupler (0702) and second photocoupler (0703)> The "first photocoupler" (0702) and the "second photocoupler" (0703) are configured so that their ON delay times are approximately equal. In this embodiment, in Fig. 7, the first photocoupler and the second photocoupler are two-circuit photocouplers sealed in one package. For example, a photocoupler TLP2105 manufactured by Toshiba Electronic Devices & Storage Corporation can be used. A similar circuit configuration may be achieved using individual components instead of an integrated package product containing two circuits, but it is empirically easier to obtain photocouplers with approximately equal ON delay times when components from the same manufacturing lot by the same manufacturer are used. When the ON delay time lengths of the first photocoupler (0702) and the second photocoupler (0703) are approximately equal, the accuracy of the calculated value can be improved when the "time difference between the first timing and the second timing" or the "time difference between the third timing and the fourth timing" is calculated by a counter and the time difference information is multiplied by 1 / 2 to calculate the zero crossing point. The time difference information is the sum of the ON delay time lengths and / or the ON advance time lengths of the first photocoupler and the second photocoupler. This is because, when the AC power supply voltage is symmetrical around the zero crossing point, the time from the threshold voltage at which the photocoupler operates to the voltage 0V (zero crossing) and the time from the voltage 0V to the voltage at which the photocoupler operates are approximately the same. For this reason, when using individual photocouplers, it is preferable to set a judgment standard and select photocouplers having approximately equal ON delay time lengths before use. In the case of a dual-circuit photocoupler, the light-emitting diode and phototransistor are manufactured by the same manufacturer and are expected to have similar characteristics. Also, unlike when each photocoupler is soldered separately onto a board, there is no concern of increased variation between photocouplers due to factors such as heat history during mounting, mounted resistors, and wiring loads on the board.

[0082] The process flow and hardware configuration of the fourth embodiment are similar to those of the third embodiment, and therefore will not be described.

[0083] By making the ON delay time lengths of the first photocoupler and the second photocoupler approximately equal, the proportions that the first photocoupler and the second photocoupler account for in the time difference between when the signals of the first photocoupler and the second photocoupler switch between L and H near the timing of the positive / negative switch of the AC power supply voltage can be made equal, and the zero crossing point can be calculated with high accuracy.

[0084] <Embodiment 5: Mainly Claim 5> Correction time length acquisition unit <Outline of the fifth embodiment> A fifth embodiment will be described. Based on the third or fourth embodiment, a corrected time length acquisition unit is provided to acquire a corrected time length by statistically processing a plurality of acquired time differences.

[0085] <Configuration of embodiment 5> Hereinafter, the functional configuration, process flow, and circuit configuration of the power interruption detection device according to the fifth embodiment of the present invention will be described on the basis of the third embodiment. Note that the same effects can be obtained on the basis of the fourth embodiment. Fig. 10 is a functional block diagram showing an embodiment of the instantaneous power interruption detection device of this embodiment. As shown in the figure, the instantaneous power interruption detection device (1000) is composed of an AC voltage zero-cross detection circuit structure (1008) consisting of an AC power signal acquisition unit (1001), a first photocoupler (1002), a second photocoupler (1003), a time difference acquisition unit (1009), a correction time length acquisition unit (1011), and a zero-cross timing acquisition unit (1010), a counter (1004), a comparison unit (1005), a comparison time length information storage unit (1006), and a comparison result output unit (1007). Since the components other than the correction time length acquisition unit (1011) are the same as those of the third embodiment, their description will be omitted. The above functional blocks are merely an example for implementing the present invention, and functions may be omitted or new functions may be added as appropriate within the scope that does not contradict the problems to be overcome by the present invention and its effects.

[0086] <Fifth embodiment: Correction time length acquisition unit (1011)> The 'corrected time length acquisition unit' (1010) is configured to perform statistical processing on a plurality of acquired time differences to acquire a corrected time length. The zero crossing point or the timing at which the AC power signal has a voltage of 0V varies from an ideal sine wave due to disturbances such as noise. To obtain a more accurate zero crossing point, the most recent variation is identified and the zero crossing point is corrected based on that variation. To make the correction, for example, the correction time length is calculated when the power signal waveform changes from negative to positive, and then the zero crossing point half a wavelength after the change from positive to negative can be calculated. In this case, the correction time length calculated by multiplying the "time difference between the first timing and the second timing" or the "time difference between the third timing and the fourth timing" by 1 / 2 can be stored and held, and the correction time length can be calculated by averaging the previous data. Alternatively, instead of all past data, a predetermined number of times can be set, only the past predetermined number of times can be stored, and the oldest data can be discarded. Until the predetermined number of times is accumulated, the correction time length can be determined by averaging only the correction time lengths accumulated so far, or the correction time length calculated each time can be used without averaging until the predetermined number of times is accumulated. Even when used to correct the zero crossing point after a half wavelength, the variation of the previous predetermined number of times can be calculated, and if it is outside the expected maximum or minimum value (e.g., equivalent to 6σ), it can be determined that there is a disturbance such as noise, and the value can be excluded and the same value as the previous time can be used as the provisional correction time length, or a preset ideal value can be used as the provisional correction time length, or zero crossing detection can be omitted. Other statistical methods such as t-tests can be used to determine the presence or absence of disturbance. When the correction time length is calculated using past correction time lengths, the correction time length cannot be obtained until a predetermined number of times has been accumulated immediately after the start, but in that case, there are methods such as using one correction time length or not performing correction until a predetermined number of times has passed, and these can be selected and set appropriately. When calculating the correction time length using past correction time lengths or when validity is verified, the extent to which past correction time lengths are used can be determined by, for example, reducing the number of correction time lengths when the variation in the correction time lengths is small, increasing the number of correction time lengths when the variation is large, or dynamically reducing the number of correction time lengths when the load of other tasks that the microcomputer used in the calculation must process becomes large, and dynamically restoring the number to the original number when the load decreases.

[0087] The instantaneous power interruption detection device (1000) of this embodiment continues to detect zero crossing points during normal operation. A method for detecting zero crossing points and acquiring a correction time length will be described with reference to FIG. 4. In the circuit of FIG. 3 in the first embodiment and the circuit of FIG. 12 in the fifth embodiment, the waveforms at points a, b, and c are equivalent, so a description will be given with reference to FIG. 4. The horizontal axis of FIG. 4 represents time, and the vertical axis represents voltage. The top point a represents the power signal waveform, which is a sine wave at point a in FIG. 12, that is, the AC power supply (1201). When point a, which represents the voltage signal obtained by the instantaneous power interruption detection device (1200) branching to have the same phase as the AC power supply source, is on the positive side, a current flows through the first photocoupler (1203a) in the two-circuit photocoupler (1203), and the light-emitting diode begins to light up. In the signal waveform diagram at point a in the figure, the two horizontal lines arranged to sandwich 0V represent the ON / OFF threshold voltages of the first and second photocouplers. During the period when the power supply signal (point a) is positive, the light-emitting diode in the first photocoupler (1203a) lights up, the phototransistor receives light, turns ON, and outputs a light-receiving signal, and point b is grounded via the phototransistor and becomes an L potential. Conversely, when the power supply signal (point a) becomes negative, the light-emitting diode in the first photocoupler (1203a) does not light up, the phototransistor turns OFF, and the light-receiving signal is no longer output, so point b is supplied with a DC positive potential Vcc potential (H potential) via resistor R and becomes an H potential. When the power supply signal (point a) is negative, the light-emitting diode in the second photocoupler (1203b) lights up, the phototransistor turns ON, and the light-receiving signal is output, so this time point c changes from an H potential to an L potential. It is possible to configure the circuit so that when the photocoupler turns ON, the potentials at points b and c become H potential instead of L potential, but this would increase the number of components such as transistors as shown in Figure 18, which is a technology from Reference 1.

[0088] Depending on whether the AC waveform of the power supply is positive or negative, the first and second photocouplers are alternately turned on, and the potentials at points b and c change in a square wave shape. Figure 4 shows the first timing to the fourth timing, which are the switching timings of the H potential and L potential of the first photocoupler output and the second photocoupler output described above. A counter (1205) measures the time between the rising and falling edges of the two square wave pulses, "first timing - second timing" or "third timing - fourth timing", and calculates the timing difference. Due to the threshold voltage at which the light-emitting diode turns on and the threshold voltage at which the phototransistor turns on, when the power supply signal switches from negative to positive and from positive to negative, it does not turn on / off correctly at a voltage of 0 V. Therefore, when comparing the pulse waveforms at points b and c near the zero crossing point where the power supply voltage becomes 0 V, a time difference occurs in the rise and fall.

[0089] The obtained time difference is multiplied by 1 / 2 in a zero cross measurement calculation (1206), and the value is used to correct the rising and falling timing of the zero cross pulse half a wavelength ahead. Applying correction to the zero crossing point half a wavelength ahead means, for example, finding half the time difference t when the power signal waveform changes from negative to positive, and then using that to correct the zero crossing point half a wavelength ahead where it changes from positive to negative. Note that when applying correction half a wavelength ahead, it may be applied to a natural number multiple of a half wavelength ahead, or it may be interpreted as applying to a natural number multiple of a half wavelength ahead. Also, half the value of the calculated time difference information is stored and held, and if the just calculated value is clearly abnormal (e.g., time difference information for a half wavelength), it is not used for correction, the previous value is used, or other processing can be performed without using half the value of the time difference information that showed the abnormal value. A statistical method may be used to determine whether the obtained correction time length is appropriate. Deviations due to the influence of disturbances such as noise can be excluded. When performing statistical processing using multiple correction time lengths and correcting to the next half wavelength ahead or a natural number multiple of a half wavelength ahead, the validity of the multiple correction time lengths to be held and the time differences to be acquired and combined for statistical processing may be evaluated by performing statistical processing using values ​​before multiplying by 2, or the correction time length may be calculated by multiplying by 2 only immediately before the time required for correction. This is because if all correction time lengths are multiplied by 2 and then held, there is a possibility that errors will accumulate due to rounding up or down if they are not divisible, and the processing load for halving will increase. The zero-cross detection output is outputted to the outside of the power interruption detection device (1200). If the ON / OFF timing of the switch section, which is made up of switching elements such as thyristors and optical MOS-FET relays, is based on the zero-cross pulse signal, it is possible to control devices such as heaters that use the same AC power supply voltage signal. By turning the switch section ON / OFF at the zero-cross point (the rising or falling edge of the zero-cross pulse), it is possible to suppress the generation of noise and inrush current in the output, and also to make the starting point of control more accurate in output adjustment by phase control.

[0090] <Processing flow of embodiment 5> Fig. 11 is an operation flow chart of the instantaneous power interruption detection device of the embodiment 3. As shown in this figure, the operation method of the instantaneous power interruption detection device of the embodiment includes a comparison time length information holding step (S1101), an AC power signal acquisition step (S1102), a fourth timing acquisition step (S1103a), a third timing acquisition step (S1103b), a first timing acquisition step (S1103c), a second timing acquisition step (S1103d), a time difference acquisition step (S1104), a correction time length acquisition step (S1105), a zero cross timing acquisition step (S1106), a comparison step (S1107), and a comparison result output step (S1108). Each step will be described below.

[0091] Here, at the timing when the AC power supply waveform changes from positive to negative, The comparative time length information holding step (S1101) performs a process of holding information indicating a comparative time length to be compared with information indicating a non-light receiving time length counted by the counter when a light receiving signal is not acquired from either the first photocoupler or the second photocoupler, The AC power signal acquisition step (S1102) performs a process of acquiring an AC power signal, The fourth timing acquisition step (S1103a) performs a process of acquiring a fourth timing, which is the timing at which the AC power waveform changes from positive to negative and is the same as a timing described later, and is the timing at which the signal rises from L to H, from a first photocoupler that outputs a signal L when the acquired AC power signal is positive and outputs a signal H when the acquired AC power signal is negative; The third timing acquisition step (S1103b) performs a process of acquiring a third timing, which is the timing at which the signal falls from H to L when the AC power waveform changes from positive to negative, from a second photocoupler that outputs a signal H when the acquired AC power signal is positive and outputs a signal L when the acquired AC power signal is negative, and is the same timing as the timing described above; The time difference acquisition step (S1104) includes a process of acquiring time difference information that is information indicating a time difference between the fourth timing and the third timing; The corrected time length acquisition step (S1105) performs a process of statistically processing a plurality of the acquired time differences to acquire a corrected time length; The zero cross timing acquisition step (S1106) performs a process of acquiring zero cross timings of the AC power supply by using the time difference information and any third timing or any fourth timing subsequent to the third timing and the fourth timing, The comparison step (S1107) performs a process of comparing a non-light receiving time length during which no light receiving signal is acquired from either the first photocoupler or the second photocoupler with the comparison time length information to be compared; The comparison result output step (S1108) performs processing to output a fact that the comparison result is a predetermined comparison result.

[0092] Here, at the timing when the AC power supply waveform changes from negative to positive, The comparative time length information holding step (S1101) performs a process of holding information indicating a comparative time length to be compared with information indicating a non-light receiving time length counted by the counter when a light receiving signal is not acquired from either the first photocoupler or the second photocoupler, The AC power signal acquisition step (S1102) performs a process of acquiring an AC power signal, In the first timing acquisition step (S1103c), a process is performed to acquire a first timing, which is the timing when the AC power waveform changes from negative to positive, which is the same as the timing described below, and is the timing when the signal rises from L to H, from a second photocoupler that outputs a signal H when the acquired AC power signal is positive and outputs a signal L when the acquired AC power signal is negative; In the second timing acquisition step (S1103d), a process is performed to acquire a second timing, which is the timing at which the signal falls from H to L when the AC power waveform changes from negative to positive, from a first photocoupler that outputs a signal L when the acquired AC power signal is positive and outputs a signal H when the acquired AC power signal is negative, and which is the same timing as the timing described above, when the AC power waveform changes from negative to positive; In the time difference acquisition step (S1104), a process is performed to acquire time difference information which is information indicating a time difference between the first timing and the second timing; The corrected time length acquisition step (S1105) performs a process of statistically processing a plurality of the acquired time differences to acquire a corrected time length; In a zero-cross timing acquisition step (S1106), a process is performed to acquire a zero-cross timing of the AC power supply using the time difference information and an arbitrary first timing or an arbitrary second timing subsequent to the first timing and the second timing, The comparison step (S1107) performs a process of comparing a non-light receiving time length during which no light receiving signal is acquired from either the first photocoupler or the second photocoupler with the comparison time length information to be compared; The comparison result output step (S1108) performs processing to output a fact that the comparison result is a predetermined comparison result. The correction time length acquisition step (S1105) may include a correction time length holding sub-step for holding the correction time length previously acquired. Furthermore, it is preferable to include a correction time length judgment step for judging whether the value obtained in the time difference acquisition step and multiplied by 1 / 2 calculated in the correction time length acquisition step is within a reasonable range. This is judged using a statistical method such as a t-test. If it is a reasonable value, it is used as the correction time length, and if it is not reasonable, a provisional correction time length is output in a provisional correction time length output step. The provisional correction time length may be determined based on an ideal value, or the correction time length used last time may be used. However, if a provisional correction time length is used, the value is not held. This is because it will become erroneous data when a statistical method is used to calculate the next correction time length. This is an operating method for causing the power interruption detection device to execute a series of processes.

[0093] <Fifth embodiment: Hardware configuration> The hardware configuration of the power interruption detection device in this embodiment will be described with reference to the drawings. Fig. 12 is a schematic diagram for explaining the circuit configuration of the power interruption detection device (1200) in embodiment 5. It is composed of an AC power supply (1201), a current limiting resistor (1202), a two-circuit photocoupler (1203), a microcomputer (1204), a counter (1205), a comparison time length information holder (1206), a comparison decision 1 (1207), a comparison result output 1 (1208), a comparison decision 2 (1209), a comparison result output 2 (1210), a zero-cross measurement calculation (1211), a zero-cross detection output (1212), a correction time length acquisition (1213) in the zero-cross measurement calculation (1211), and the like. A signal is obtained from the AC power supply (1201) to detect the zero crossing point, and a momentary interruption in the power supply from the AC power supply (1201) is judged based on the detected zero crossing point. It is preferable to configure the circuit system so that there is no phase shift between the AC power supply signal for measuring the zero crossing point used for detection and the comparison result outputs 1 and 2. This is because if the comparison result is output later than the specified time information, the momentary interruption detection will not be effective. The two-circuit photocoupler (1203) may be configured using a photocoupler for each circuit. 9 in that the correction time length acquisition (1213) is provided within the zero-cross measurement calculation (1211). As described above, the correction time length acquisition (1207) can be used to acquire and store past correction time lengths, and to find the next correction time length from the correction time lengths for a predetermined number of times just before that, or to determine whether the correction time length just before a half wavelength is an abnormal value based on the correction time lengths for the past predetermined number of times, and if it is within the normal range, to use it as the correction time length when calculating the next zero-cross point.

[0094] In contrast to the third embodiment, the fifth embodiment performs statistical processing on a plurality of acquired time differences to acquire a correction time length for calculating the zero crossing point, thereby making it possible to determine the zero crossing point with higher accuracy. Based on the acquired zero crossing point, a zero crossing detection output used for controlling the switches of other devices can be output as a more accurate value.

[0095] <Embodiment 6: Mainly Claim 6>: Photocoupler ON and output L <Overview of embodiment 6> A sixth embodiment will be described. Based on any one of the third to fifth embodiments, the first and second photocouplers configure an instantaneous power interruption detection device such that the output becomes L when the photocoupler is ON.

[0096] <Configuration of embodiment 6> Hereinafter, a momentary power interruption detection device according to the sixth embodiment of the present invention will be described based on the third embodiment. The same effects can be obtained even if the fourth or fifth embodiment is used as a base. The functional configuration, the process flow, and the circuit configuration will be described in that order. The functional configuration is the same as in the third embodiment. An explanation will be given by utilizing Fig. 7. As shown in Fig. 7, the power interruption detection device (0700) is composed of an AC voltage zero-cross detection circuit structure (0708) composed of an AC power signal acquisition unit (0701), a first photocoupler (0702), a second photocoupler (0703), a time difference acquisition unit (0709), and a zero-cross timing acquisition unit (0710), a counter (0704), a comparison unit (0705), a comparison time length information storage unit (0706), and a comparison result output unit (0707). The parts that differ from the third embodiment will be explained. The above functional blocks are merely an example for implementing the present invention, and functions may be omitted or new functions may be added as appropriate within the scope that does not contradict the problems to be overcome by the present invention and its effects.

[0097] <Embodiment 6: First photocoupler (0702)> The "first photocoupler" (0702) is configured to output a signal L when the acquired AC power signal is positive and to output a signal H when the acquired AC power signal is negative, and is further configured such that the output signal becomes L when the photocoupler is ON.

[0098] <Embodiment 6: Second Photocoupler (0703)> The "second photocoupler" (0703) is configured to output a signal H when the acquired AC power signal is positive and to output a signal L when the acquired AC power signal is negative, and is further configured such that the output signal becomes L when the photocoupler is ON. It is possible to configure the circuit so that the output becomes H when the photocoupler is ON, but this can be achieved by adding one transistor and one resistor to the photocoupler output (light receiving element side) as shown in the circuit of prior art document 1 in Figure 14. In the case of the present invention, two photocouplers are used, so two additional transistors and two additional resistors are required, which increases the number of parts and the cost. For this reason, it is preferable to configure the output so that the output becomes L when the photocoupler is ON.

[0099] <Embodiment 6: Time difference acquisition unit (0704)> The "time difference acquisition unit" (0704) is "the time difference between the first timing at which the second photocoupler turns OFF and the output signal switches from L to H, and the second timing at which the first photocoupler turns ON and the output signal switches from H to L, in the same timing region in which the AC power supply signal is inverted from negative to positive" or / and, It is configured to acquire the time difference between a third timing at which the second photocoupler turns ON and the output signal switches from H to L, and a fourth timing at which the first photocoupler turns OFF and the output signal switches from L to H, in the same timing region where the AC power supply signal is inverted positive and negative.

[0100] <Processing flow of embodiment 6> The process flow is almost the same as that of the third embodiment. The operation flow chart of the power interruption detection device of the third embodiment will be used for the explanation in FIG. 8. As shown in this figure, the operation method of the AC voltage zero-cross detection circuit structure of the sixth embodiment includes a comparison time length information holding step (S0801), an AC power signal acquisition step (S0802), a fourth timing acquisition step (S0803a), a third timing acquisition step (S0803b), a first timing acquisition step (S0803c), a second timing acquisition step (S0803d), a time difference acquisition step (S0804), a zero-cross timing acquisition step (S0805), a comparison step (S0806), and a comparison result output step (S0807). The following describes the differences between each step and the third embodiment.

[0101] Here, at the timing when the AC power supply waveform changes from positive to negative, The AC power signal acquisition step (S0801) performs a process of acquiring an AC power signal branched from an AC power source supplied to a component to be controlled, In the fourth timing acquisition step (S0802a), a process is performed to acquire a fourth timing, which is the timing at which the AC power waveform changes from positive to negative from a first photocoupler that is turned ON and outputs an output signal L when the acquired AC power signal is positive, and is turned OFF and outputs an output signal H when the acquired AC power signal is negative, and is the same timing as a timing described later, and is the timing at which the first photocoupler is turned OFF and the output signal rises from L to H; In the third timing acquisition step (S0802b), a process is performed to acquire a third timing, which is the timing when the second photocoupler turns ON and the output signal falls from H to L when the acquired AC power signal is positive, from a second photocoupler which turns OFF and outputs an output signal H when the acquired AC power signal is positive, and turns ON and outputs an output signal L when the acquired AC power signal is negative, when the AC power waveform changes from positive to negative, and which is the same timing as the timing described above. In the time difference acquisition step (S0803), a process of acquiring time difference information which is information indicating a time difference between the fourth timing and the third timing is performed; In the zero cross timing acquisition step (S0804), a process is performed to acquire the zero cross timing of the AC power source using this time difference information and any third timing or any fourth timing that follows the third timing and fourth timing.

[0102] Here, at the timing when the AC power supply waveform changes from negative to positive, The AC power signal acquisition step (S0801) performs a process of acquiring an AC power signal branched from an AC power source supplied to a component to be controlled, In the first timing acquisition step (S0802c), a process is performed to acquire a first timing from a second photocoupler which is turned OFF and outputs an output signal potential H when the acquired AC power signal is positive, and which is turned ON and outputs an output signal potential L when the acquired AC power signal is negative, the first timing being the timing when the AC power waveform changes from negative to positive, which is the same as the timing described below, and which is the timing when the second photocoupler is turned OFF and the output signal rises from L to H; In the second timing acquisition step (S0802d), a process is performed to acquire a second timing, which is the timing at which the output signal of the first photocoupler falls from H to L when the AC power waveform changes from negative to positive, from a first photocoupler which turns ON and outputs an output signal potential L when the acquired AC power signal is positive, and turns OFF and outputs an output signal potential H when the acquired AC power signal is negative, and which is the same timing as the timing described above, when the AC power waveform changes from negative to positive; In the time difference acquisition step (S0803), a process is performed to acquire time difference information which is information indicating a time difference between the first timing and the second timing; In the zero cross timing acquisition step (S0804), a process is performed to acquire the zero cross timing of the AC power supply using this time difference information and any first timing or any second timing that follows the first timing and second timing. If the time difference information obtained after the time difference acquisition step (S0803) is within a normal range or is clearly considered to be abnormal, such as a value equivalent to a half wavelength, it can be configured to determine that the time difference is abnormal and not use the calculated time difference information. In that case, the previously calculated time difference information can be used again, or the time difference can be treated as 0, assuming that there is no time difference. This is an operating method for causing the AC voltage zero cross detection circuit structure to execute a series of processes.

[0103] <Embodiment 6: Hardware Configuration> The hardware configuration of the structure in this embodiment will be described with reference to FIG. 9 showing the third embodiment. When the first photocoupler or the second photocoupler is turned ON (i.e., when the light-emitting diode is lit and the phototransistor receives light and turns ON), the circuit in FIG. 9 is configured so that point b or point c in the figure changes from H potential to L potential. Note that the circuit can also be configured so that the potential of point b or point c becomes H potential instead of L potential when the photocoupler is turned ON, but since this increases the number of parts such as transistors and resistors as shown in FIG. 18, which is the technology of Literature 1, the configuration as shown in FIG. 9 is preferable.

[0104] <Embodiment 7: Mainly Claim 5>: Preemptive means <Overview of embodiment 7> A seventh embodiment will be described. Based on any one of the third to sixth embodiments, a zero-cross timing acquisition unit is provided with a pre-acquisition means for acquiring the zero-cross timing by using the timing at which the signal of the first photocoupler rises from L to H just before the zero-cross timing and a correction time length when the AC power supply signal inverts from positive to negative, and acquiring the zero-cross timing by using the timing at which the signal of the second photocoupler rises from L to H just before the zero-cross timing and a correction time length when the AC power supply signal inverts from negative to positive.

[0105] <Configuration of embodiment 7> The following describes the functional configuration, processing flow, and circuit configuration of a power interruption detection device according to the seventh embodiment of the present invention, based on the fifth embodiment. The same effects can be obtained even when based on the third, fourth, or sixth embodiments. Fig. 13 is a functional block diagram showing an embodiment of the instantaneous power interruption detection device of this embodiment. As shown in the figure, the instantaneous power interruption detection device (1300) is composed of an AC power signal acquisition unit (1301), a first photocoupler (1302), a second photocoupler (1303), a time difference acquisition unit (1309), a correction time length acquisition unit (1311), a zero cross timing acquisition unit (1310), and an AC voltage zero cross detection circuit structure (1308) composed of a pre-acquisition means (1312) provided in the zero cross timing acquisition unit (1310), a counter (1304), a comparison unit (1305), a comparison time length information storage unit (1306), and a comparison result output unit (1307). Since the pre-acquisition means (1312) is the same as in the third embodiment, a description thereof will be omitted. The above functional blocks are merely an example for implementing the present invention, and functions may be omitted or new functions may be added as appropriate within the scope that does not contradict the problems to be overcome by the present invention and its effects.

[0106] <Embodiment 7: Preemption Means (1312)> The "pre-acquisition means" (1312) is configured in the zero-cross timing acquisition unit (1310) so as to acquire the zero-cross timing using the timing when the signal of the first photocoupler rises from L to H when the AC power supply signal inverts from positive to negative, and to acquire the zero-cross timing using the timing when the signal of the second photocoupler rises from L to H when the AC power supply signal inverts from negative to positive. Fig. 16 shows signal waveforms at various points (see a, b, and c in the circuit diagram of Fig. 15) in the circuit of the power interruption detection device in embodiment 7. The preemption means (1312) will be described with reference to Fig. 16. F0, D0, F1, and D1 on the vertical axis represent the zero crossing points. F is when the AC power signal goes from negative to positive. n (n=0, 1,), and when it goes from positive to negative, it is Dn(n=0, 1,). n and D n A on both sides of n , B n , C n , E n indicate the points at which the ON / OFF threshold voltages of the first and second photocouplers are reached, as shown in the figure. For example, near point F0 where the AC power supply signal changes from negative to positive, the time difference t1 between A0 where the second photocoupler turns OFF and the output changes, and B0 where the first photocoupler turns ON and the output changes, is obtained by the correction time length acquisition unit (1311), and 1 / 2 of that t1 is added to the timing where the first photocoupler turns OFF and the output changes from L to H at the falling edge of the AC power supply signal from positive to negative in the next half wavelength, thereby making it possible to obtain the zero-cross timing (i.e., the zero-cross point) earlier than real time. Near point D0 where the AC power supply signal changes from positive to negative, the time difference t2 between C0 where the first photocoupler turns OFF and the output changes, and E0 where the second photocoupler turns ON and the output changes is obtained by a correction time length acquisition unit (1311). By adding 1 / 2 of the obtained t2 to the timing where the second photocoupler turns OFF and the output changes from L to H at the rising edge of the AC power supply signal from negative to positive in the next half wavelength, the zero cross timing (i.e., the zero cross point) can be obtained earlier than the actual zero cross point is reached. For example, the microcontroller's operation is to start counting in a counter when the output of the first photocoupler at C0 changes from signal L to signal H, and to halt counting when the output of the second photocoupler at E0 changes from signal H to signal L. The obtained count value is multiplied by 1 / 2, and the average count value is calculated as the correction time length using a predetermined number of past correction time lengths (count values) that are held. The operation is to change the zero-cross pulse signal potential from L to H when the calculated correction time length (count value) has passed since the timing when the output of the second photocoupler at A1, half a wavelength ahead, changed from signal L to signal H. If the ON delay time length and / or ON advance time length of the first photocoupler and the second photocoupler are approximately equal, the contributions of both photocouplers to the time difference (for example, t2) will be equal, and the accuracy of the value obtained by multiplying the time difference, which is the correction time length, by 1 / 2 will be improved.

[0107] The timing at which the output signal of the first photocoupler or the second photocoupler changes from H to L is called T na The timing when the output signal of the second photocoupler or the first photocoupler changes from L to H is T nb n starts from 1 with an arbitrary time as the starting point, and is used to number and distinguish the timing when the photocoupler output signal changes. 1a , T 1b , T 2a , T 2b ,,,T (n-1)a , T (n-1)b , T na , T nb , T (n+1)a , T (n+1)b , and so on. The time difference between the timings is t n Then, tn can be expressed as follows: t n =T nb -T na The average time difference between n timings, Δt n teeth, (t1+t2+t3+…+t n-2 +t n-1 +tn ) / n = Δt n It becomes as follows. When calculating the correction time length by halving the time difference, Δt n / 2 = Δt n ' The zero-crossing point at half-wavelength ahead is obtained by the following formula. Zero (n+1) = T (n+1)a + Δt n ' When obtaining the correction time length based on the time difference between timings at the n-th time point, the average value of n is calculated, but it may be possible to trace back a predetermined number of times k from the n-th time point to the past. 1 ≤ k < n. This is because as n increases, the data retention memory area for the past correction time length increases and the processing load also increases.

[0108] Next, the verification of the validity of the obtained correction time length Δt n ' will be explained taking the t-test as an example. Let the number of samples used for verification be m. (1 ≤ m < n) The t-value in the t-test is t = (average of m - Δt n ) / (standard deviation / √m) It can be expressed as follows. Calculate the p-value, and if it is 5% or less, which is generally used as the significance level, it is judged to be valid. The number m of correction time lengths used for verification may be dynamically reduced, for example, when the deviation of the correction time length is small or when the load increases including other processes of the microcomputer.

[0109] Hereinafter, the case of performing a t-test using the past 10 correction time lengths will be described as an example, but it is not limited to 10, and it may be more or less. The zero-crossing point F0 at the leftmost time point in Fig. 6 is at the start time of the circuit operation, so the correction time length has not been calculated yet. The change points A0 and B0 of the waveforms of the first photocoupler output and the second photocoupler output are due to the ON / OFF thresholds of the respective photocouplers. For a two-circuit photocoupler, it can be expected that the ON / OFF thresholds are substantially equal. A n , B n , C n, E n The time (count value) at A n , B n , C n , E n The time difference information (count value) at each zero crossing point is divided by 2 to get T Fn , T Dn is expressed by the following formula: T F0 =(B0-A0) / 2 T F1 =(B1-A1) / 2 … T Fn =(B n -A n ) / 2 n=1,2,3,… T D0 =(E0-C0) / 2 T D1 =(E1-C1) / 2 … T Dn =(E n -C n ) / 2 n=1,2,3,… When estimating each average value, if we refer to the past 10 samples, The estimated upper and lower limits of the variation in the correction time length are given as follows: T FnL,H =T Fn ±t(10-1,0.05)×(V F / (10-1)) (1 / 2) T DnL,H =T Dn ±t(10-1,0.05)×(V D / (10-1)) (1 / 2) t(10-1,0.05) is the correction time length Δt n ' represents the test quantity of the t-test at a significance level of 5% for the past 10 samples, and V F , V D represents the respective variance values. Therefore, in the above two equations, T FnL is the lower limit estimate based on the correction time length calculated at the Fn point, T FnHrepresents the upper limit estimate when there is variation. It is verified whether it is within the range that includes the deviation from the average value of the past 10 items. Correction time length T Fn and T Dn A n and C n The value added to this becomes the zero crossing point. F n Corrected time length T obtained at point Fn From the lower and upper estimates of F n E half wavelength ahead of the point n The point is C n It is expected that the points are within the range of the following formula. n Similarly, the point D is half a wavelength ahead. n Corrected time length T obtained at point Dn It is expected that the range from the lower and upper estimates of C n +2T FnL <E n <C n +2T FnH A n +T Dn-1L n n +2T Dn-1H If it is not within the range of the above formula, F n Or D n At this point, it is assumed that a disturbance such as noise has occurred, and the zero cross pulse is not corrected using the value calculated by statistical processing. In the above case, a provisional correction time length is applied, but the procedure is determined in advance, such as using a provisional correction time length determined from an ideal value, or applying the previous correction time length. If correction is not performed using the calculated correction time length, the value is not retained even if the provisional correction time length is applied. This is because it is not used when performing statistical processing based on the retained past correction time lengths to calculate the next correction time length and to evaluate the validity of the calculated correction time length.

[0110] ​​The significance level of 5% in the above explanation corresponds to a 5% defect rate (95% good products, equivalent to 2σ). The oversight rate is usually expected to be about twice as high as a 5% defect rate, so it is 10%. Therefore, it is believed that by looking at 10 runs, it is possible to eliminate any products that are significantly out of line. Although the correction time length of the past 10 times was referenced, it is not limited to 10 times. When performing statistical processing, the more samples there are, the more accurate the variation and the higher the accuracy. However, if the number of samples is increased, the correction starts later even if a fluctuation occurs, the amount of data to be stored increases, the memory area increases, and the amount of memory used temporarily during calculation increases, which increases the cost of parts. There are also disadvantages such as an increase in the calculation load on the CPU and the calculation time required, which is a trade-off with accuracy. The calculation load of the microcontroller may be monitored and the number of times the past correction time length used in the statistical method is referenced may be dynamically changed. In that case, it is advisable to determine the range of the minimum and maximum numbers. Also, depending on the frequency of occurrence of a situation where the value obtained by multiplying the obtained time difference by 1 / 2 cannot be used due to the influence of disturbances on the power signal waveform, the number of past correction time lengths to be referenced may be increased or decreased. Generally, the number of samples for statistical processing is around 30, but the designer can select the number of samples as appropriate.

[0111] <Processing flow of embodiment 7> Fig. 14 is an operation flow chart of the instantaneous power interruption detection device of the seventh embodiment. As shown in this figure, the operation method of the instantaneous power interruption detection device of the seventh embodiment includes a comparison time length information holding step (S1401), an AC power signal acquisition step (S1402), a fourth timing acquisition step (S1403a), a third timing acquisition step (S1403b), a first timing acquisition step (S1403c), a second timing acquisition step (S1403d), a time difference acquisition step (S1404), a correction time length acquisition step (S1405), a zero cross timing acquisition step (S1406), a look-ahead sub-step (S1407) provided in the zero cross timing acquisition step (S1406), a comparison step (S1408), and a comparison result output step (S1409). Each step will be described below.

[0112] Here, at the timing when the AC power supply waveform changes from positive to negative, The comparative time length information holding step (S1401) performs a process of holding information indicating a comparative time length to be compared with information indicating a non-light receiving time length counted by the counter when a light receiving signal is not acquired from either the first photocoupler or the second photocoupler, The AC power signal acquisition step (S1402) performs a process of acquiring an AC power signal, The fourth timing acquisition step (S1403a) performs a process of acquiring a fourth timing, which is the timing at which the AC power waveform changes from positive to negative, which is the same as the timing described below, and is the timing at which the signal rises from L to H, from a first photocoupler that outputs a signal L when the acquired AC power signal is positive and outputs a signal H when the acquired AC power signal is negative; The third timing acquisition step (S1403b) performs a process of acquiring a third timing, which is the timing at which the signal falls from H to L when the AC power waveform changes from positive to negative, from a second photocoupler that outputs a signal H when the acquired AC power signal is positive and outputs a signal L when the acquired AC power signal is negative, and is the same timing as the timing described above; The time difference acquisition step (S1404) includes a process of acquiring time difference information that is information indicating a time difference between the fourth timing and the third timing; The corrected time length acquisition step (S1405) performs a process of statistically processing a plurality of the acquired time differences to acquire a corrected time length; A pre-emption sub-step (S1407) provided in the zero-cross timing acquisition step (S1406) performs a process of acquiring the zero-cross timing by using a fourth timing at which the signal of the first photocoupler rises from L to H immediately before the zero-cross timing and a correction time length when the AC power signal inverts from positive to negative, The comparison step (S1408) performs a process of comparing a non-light receiving time length during which no light receiving signal is acquired from either the first photocoupler or the second photocoupler with the comparison time length information to be compared, The comparison result output step (S1409) performs processing to output a fact that the comparison result is a predetermined comparison result.

[0113] Here, at the timing when the AC power supply waveform changes from negative to positive, The comparative time length information holding step (S1401) performs a process of holding information indicating a comparative time length to be compared with information indicating a non-light receiving time length counted by the counter when a light receiving signal is not acquired from either the first photocoupler or the second photocoupler, The AC power signal acquisition step (S1402) performs a process of acquiring an AC power signal, In the first timing acquisition step (S1403c), a process is performed to acquire a first timing, which is the timing at which the AC power waveform changes from negative to positive, which is the same as the timing described below, and is the timing at which the signal rises from L to H, from a second photocoupler that outputs a signal H when the acquired AC power signal is positive and outputs a signal L when the acquired AC power signal is negative; In the second timing acquisition step (S1403d), a process is performed to acquire a second timing, which is the same timing as the timing at which the signal falls from H to L when the AC power waveform changes from negative to positive, from a first photocoupler that outputs a signal L when the acquired AC power signal is positive and outputs a signal H when the acquired AC power signal is negative, and In the time difference acquisition step (S1404), a process is performed to acquire time difference information which is information indicating a time difference between the first timing and the second timing; The corrected time length acquisition step (S1405) performs a process of statistically processing a plurality of the acquired time differences to acquire a corrected time length; The zero-cross timing acquisition step (S1406) includes a sub-step (S1407) for acquiring the zero-cross timing when the AC power supply signal inverts from negative to positive, and the processing for acquiring the zero-cross timing using a first timing at which the signal of the second photocoupler rises from L to H immediately before the zero-cross timing and a correction time length. The comparison step (S1408) performs a process of comparing a non-light receiving time length during which no light receiving signal is acquired from either the first photocoupler or the second photocoupler with the comparison time length information to be compared, The comparison result output step (S1409) performs processing to output a fact that the comparison result is a predetermined comparison result. The correction time length acquisition step (S1405) may include a correction time length holding sub-step for holding the correction time length previously acquired. Furthermore, it is preferable to include a correction time length judgment step for judging whether the value obtained in the time difference acquisition step and multiplied by 1 / 2 calculated in the correction time length acquisition step is within a reasonable range. This is judged using a statistical method such as a t-test. If it is a reasonable value, it is used as the correction time length, and if it is not reasonable, a provisional correction time length is output in a provisional correction time length output step. The provisional correction time length may be determined based on an ideal value, or the correction time length used last time may be used. However, if a provisional correction time length is used, the value is not held. This is because it will become erroneous data when a statistical method is used to calculate the next correction time length. This is an operating method for causing the power interruption detection device to execute a series of processes.

[0114] <Seventh embodiment: Hardware configuration> The hardware configuration of the power interruption detection device in this embodiment will be described with reference to the drawings. Fig. 15 is a schematic diagram for explaining the circuit configuration of the power interruption detection device (1500) in the seventh embodiment. It is composed of an AC power supply (1501), a current limiting resistor (1502), a photocoupler with two circuits (1503), a microcomputer (1504), a counter (1505), a comparison time length information storage (1506), a comparison decision 1 (1507), a comparison result output 1 (1508), a comparison decision 2 (1509), a comparison result output 2 (1510), a zero-cross measurement calculation (1511), a zero-cross detection output (1512), a correction time length acquisition (1513) in the zero-cross measurement calculation (1511), and a pre-fetching means (1514) in the zero-cross detection output (1512). A signal is obtained from the AC power supply (1501) to detect the zero crossing point, and a momentary interruption in power supply from the AC power supply (1501) is judged based on the detected zero crossing point. It is preferable to configure the circuit system so that there is no phase shift between the AC power supply signal for measuring the zero crossing point used for detection and the comparison result outputs 1 and 2. This is because if the comparison result is output later than the specified time information, the momentary interruption detection will not be effective. The two-circuit photocoupler (1503) may be configured using a photocoupler for each circuit.

[0115] In the seventh embodiment, the zero cross point that can be the starting point for detecting an instantaneous interruption period is calculated by applying the obtained correction time length to a half wavelength ahead of the AC power supply voltage waveform, so that the zero cross point can be determined prior to the time when the zero cross (voltage 0 V) ​​actually occurs.

[0116] <Another example of preemptive measures> In the first to seventh embodiments, the time between the rising and falling of the first and second photocouplers (t1, t2, t3 in FIG. 16) is measured by a counter, but the period of the output signal of the first photocoupler and the output signal of the second photocoupler may be measured. This will be explained with reference to FIG. 16. For example, the number of counts elapsed since startup is monitored, the number of counts at point B0 where the output of the first photocoupler changes from signal H to signal L is recorded, and the period of signal L is counted. Next, the number of counts at point C0 where the output changes from signal L to signal H is recorded, and the period of signal H is counted. Similarly, the number of counts at points B1 and C1 are recorded. Similarly, the number of counts at points A0, E0, A1, E1, etc. are measured and recorded for the output signal of the second photocoupler. The time difference between the rise and fall of the first photocoupler and the second photocoupler is obtained as a count number by t1 = (count number at point B0 - count number at point A0). The correction time length is obtained as t1 / 2. The correction time length t1 / 2 obtained as in the seventh embodiment can be added to point C0 where the output of the first photocoupler, which is a half wavelength ahead, changes from signal L to signal H to generate a zero crossing pulse. In addition, since the count number of the signal H period and the signal L period of the output signal waveform of the photocoupler are recorded, for example, when the correction time length t2 / 2 near point D0 is calculated and then applied to point F1, the zero crossing point near point F1 can be obtained by adding the count number of the H period of the first photocoupler obtained in the past to the count number at point C0 and subtracting the correction time length t2 / 2. In a commercial single-phase AC power supply, the variation in the zero crossing point is about 80 μsec, but the zero crossing point can be found in advance by the time (almost 10 ms) obtained by subtracting the time required for calculating the correction time length from the half-cycle time of 10 ms. When finding the zero crossing point near point D1 based on the L period count number, it can be obtained by adding the L period count number to the count number at point B1 and adding the correction time length t3 / 2. It can be found in the same way when the second photocoupler is used. A more accurate value can be obtained by using only one of them, or by comparing the values ​​obtained by using both separately, or by comparing with the calculation method of embodiment 7.

[0117] <Embodiment 8, mainly claims 10 to 12>: Momentary voltage drop detection <Overview of embodiment 8> The eighth embodiment is based on any one of the first to seventh embodiments and is configured to also have a voltage sag detection function. <Configuration of embodiment 6> The eighth embodiment will be described based on the seventh embodiment. The same effects can be obtained based on the first to sixth embodiments. Fig. 19 is a functional block diagram showing an embodiment of an AC power interruption and dip detection device (1900) according to the present embodiment. As shown in FIG. 19, the AC power interruption and voltage drop detection device (1900) is composed of an AC power signal acquisition unit (1901), a first photocoupler (1902), a second photocoupler (1903), a time difference acquisition unit (1909), a correction time length acquisition unit (1911), a zero-cross timing acquisition unit (1910), a predictive means (1912) provided in the zero-cross timing acquisition unit (1910), a counter (1904), a comparison unit (1905), a comparison result output unit (1907), a voltage drop unit (1913), an AC full-wave rectification unit (1914), an AD conversion unit (1915), an integration unit (1916), a comparison predetermined value holding unit (1917), an abnormality / normality determination unit (1918), a determination result output unit (1919), and a microcomputer (1920). The AC power signal acquisition unit (1901), first photocoupler (1902), second photocoupler (1903), time difference acquisition unit (1909), correction time length acquisition unit (1911), zero cross timing acquisition unit (1910), advance acquisition means (1912) provided in the zero cross timing acquisition unit (1910), counter (1904), comparison unit (1905), and comparison result output unit (1907) that constitute the momentary interruption detection function are the same as those in the seventh embodiment, and therefore description thereof will be omitted. The above functional blocks are merely an example for implementing the present invention, and functions may be omitted or new functions may be added as appropriate within the scope that does not contradict the problems to be overcome by the present invention and its effects.

[0118] <Embodiment 8: Voltage drop section (1913)> The "voltage drop section" (1913) is configured to have an isolation transformer for stepping down the AC power supply voltage. The original AC power signal is a general commercial AC power source with a value of about 85V to 264V, which is a high voltage for electronic devices such as microcontrollers, so an insulating step-down transformer is used to step it down to a level of a few volts that can be handled. The phase lag occurs due to the inductive reactance of the transformer coil, but this is within the acceptable range for momentary sag detection.

[0119] <Embodiment 8: AC full-wave rectifier (1914)> The "AC full-wave rectification unit" (1914) is configured to full-wave rectify the AC voltage stepped down by the power supply voltage step-down unit (1913). Rectification is performed using diodes capable of full-wave rectification of AC or other common techniques.

[0120] <Embodiment 8 AD conversion unit (1915)> The 'AD conversion unit' (1915) is configured to perform AD conversion on the full-wave rectified waveform. An AD conversion is performed so that the integration part, which will be described later, can integrate the signal to calculate the area of ​​a half wavelength of the AC. Although it depends on the accuracy of the AD converter of the microcontroller used, a converter of about 10 bits is preferable.

[0121] <Embodiment 8: Integration section (1916)> The 'integration section' (1916) is configured to integrate the AD converted half wavelength. The integration section integrates the section between the half wavelengths of the AD converted signal that is sandwiched between voltages equivalent to 0. The zero crossing points on both sides corresponding to the corresponding half wavelength may be calculated by an AC voltage zero crossing detection circuit structure, and the time length between them may be integrated. This method is more preferable because it provides a more accurate integral interval.

[0122] <Embodiment 8: Comparison Predetermined Value Storage Unit (1917)> The 'predetermined comparative value holding unit' (1917) is configured to hold a predetermined comparative value, which is a predetermined value for determining whether the integral value of each obtained half wavelength is normal. A specified value is held as a criterion for determining whether a voltage sag (i.e., abnormality) is present or normal. For example, a voltage sag is determined to occur when it falls below 80% of normal. Since the level of voltage sag that affects the device requiring the determination result differs, it is also possible to make the setting selectable depending on the target device.

[0123] <Embodiment 8: Abnormal / normal judgement unit (1918)> The 'abnormal / normal judgment unit' (1918) is configured to compare the obtained integral value of each half wavelength with a stored comparison predetermined value and judge whether it is an abnormal voltage sag state or a normal state. The judgment is made by comparing the integration results for a half wavelength, so it is performed every half wavelength. Therefore, even if a voltage sag occurs at the present time, it will be judged as a voltage sag after a half wavelength, and even if the voltage returns to normal, it will be judged as a return to normal after a half wavelength. It is determined whether the state is an abnormal voltage sag or normal, but since the criteria for determination differ depending on the device requiring the determination result as described above, it is preferable to be able to switch so that the determination is made based on a selected comparison value. Detection of a momentary interruption begins almost immediately after its occurrence, but for a momentary sag, integral calculation is performed after a half-wavelength. Therefore, there is a non-light-receiving period in which no light-receiving signal is output from both photocouplers, and if there is concern about a momentary interruption, it is preferable to determine that a momentary interruption has occurred, output a momentary interruption detection signal, and not perform momentary sag detection processing. For example, when a momentary interruption is detected by the momentary interruption detection device, an interrupt process is also performed on the momentary sag detection device to stop the momentary sag detection process. Alternatively, a lower limit value may also be stored as a predetermined value used as a judgment criterion for the comparison, and momentary sag detection may not be performed if the lower limit value is reached or falls below.

[0124] <Embodiment 8: Judgment result output unit (1919)> The 'judgment result output unit' (1919) is configured to output the judgment result. If the judgment result is an abnormality (voltage drop), it is preferable to open the output (OFF potential) and to keep it ON (H potential) under normal circumstances. Voltage drops are abnormal situations, and assuming a breakdown in the voltage drop detection or a disconnection in the line transmitting the detection result, it is believed that there will be less damage if the abnormality, including the abnormality of the equipment, is transmitted, rather than not transmitting the abnormality result at all.

[0125] <Embodiment 8: AC power signal acquisition unit (1901)> The 'AC power signal acquisition unit' (1901) is configured to be shared with any one of the power interruption detection devices according to the first to seventh embodiments. The momentary interruption detection device and at least the AC power signal acquisition unit are shared by the momentary interruption detection device. Functionally, if the counter function of the microcomputer functions as the counter of the momentary interruption detection device and also performs at least one of the functions of the AD conversion unit, integration unit, comparison predetermined value holding unit, abnormality / normality determination unit, and determination result output unit of the momentary interruption detection device, it is possible to reduce the number of parts and configure the device to be able to detect momentary interruptions and momentary sags with one device. Furthermore, when the voltage sag detection device integrates the rectified AC waveform over a half-wavelength to determine a voltage sag, the zero-crossing points of the AC waveform used by the instantaneous interruption detection device to detect an instantaneous interruption are used to determine the integration range, thereby improving the accuracy of the integration results. This is because when full-wave rectification is performed, there is a period of 0V voltage near the zero-crossing point for a period that corresponds to the operating threshold of the rectifier diode, making it difficult to accurately calculate the zero-crossing point.

[0126] <Processing flow of embodiment 8> The process flow of this embodiment is as follows: In the comparative predetermined value holding step, a comparative predetermined value is held, which is a predetermined value for determining whether the integral value of each half wavelength obtained is normal, In the AC power signal acquisition step, a process of acquiring an AC power signal is performed; In the voltage drop step, the AC power supply voltage is stepped down by an isolation transformer. In the AC full-wave rectification step, a process of full-wave rectifying the AC voltage stepped down in the power supply voltage step is performed; In the AD conversion step, the full-wave rectified waveform is converted into an AD signal. In the integration step, the AD converted half wavelength is integrated. In the abnormality / normality determination step, the obtained integral value of each half wavelength is compared with a stored comparison predetermined value to determine whether the voltage is in an abnormal voltage sag state or a normal state, In the determination result output step, a process of outputting the determination result is carried out. This is an operating method for causing the power voltage sag detection device to execute a series of processes.

[0127] <Embodiment 8 Hardware Configuration> The hardware configuration of the power dip detection device in this embodiment will be described with reference to FIG. 20 which shows an outline of the circuit configuration. It is composed of an AC power supply (2001), a current limiting resistor (2002), a dual-circuit photocoupler (2003), a microcontroller (2004), a counter (2005), a comparison time length information holder (2006), a comparison judgment 1 (2007), a comparison result output 1 (2008), a comparison judgment 2 (2009), a comparison result output 2 (2010), a zero-cross measurement calculation (2011), a zero-cross detection output (2012), a correction time length acquisition unit (2013) within the zero-cross measurement calculation (2011), a pre-emption means (2014) within the zero-cross detection output (2012), an insulating transformer (2015), a rectifier (2016), an AD converter (2017), an integrator (2018), an integral value comparison (2019), a comparison predetermined value holder (2020), and a comparison result output (2021). The operation of the voltage sag detection device will be described with reference to FIGS. 20 and 21. The AC power signal is received from the AC power source (2001) that is also used as a component for detecting momentary interruptions. The signal waveform is a sine wave as shown in the top graph of Figure 21. Starting from the left, the graph shows normal, abnormal, abnormal, normal, and normal in half-wavelengths. The horizontal dotted lines above and below the AC waveform indicate the upper and lower ends of the normal waveform. The voltage is stepped down to a level of several volts by an isolation transformer (2015). When full-wave rectified by a full-wave rectifier (2016), the waveform at point e on the input side of the AD converter in Figure 20 is shown in the third graph from the top of Figure 21. The AC waveform is all rectified to the positive voltage side. The part with the abnormal value is the momentary dip period. In Figure 21, it is two peaks marked abnormal. The figure is drawn with almost no gap between the peaks, but because the operating threshold voltage of a diode is generally about 0.6 V, a period of 0 V voltage of about 100 μs occurs. The full-wave rectified waveform is converted by an AD converter (2017). The obtained value is integrated by an integrator (2018). Integration is performed from the above-mentioned 0V voltage section until the section returns to 0V. Depending on the distortion of the waveform near 0V voltage, it is possible that a period shifted from the actual zero crossing point may be integrated. The integrated result is compared with the comparison specified value stored in the comparison specified value hold (2020), and an integration value comparison (2019) is used to determine whether the normal value is an abnormal value. The determined result is output as a voltage sag detection output from the comparison result output (2021). When outputting, it is preferable that the output is ON (H potential) during normal times and OFF (L potential: open) during abnormal times. By combining the functionally compatible parts of the momentary interruption detection device and the microcontroller, it is possible to obtain a device that combines both functions with a small number of parts by simply adding an isolation transformer and a full-wave rectifier. Furthermore, when integrating with the integrator (2018), the zero-cross detection output regarding the zero-cross points from the AC voltage zero-cross detection circuit structure in the momentary interruption detection device is used to obtain the time difference (count difference) between the zero-cross points at both ends of the half wavelength that is most recently to be integrated, and the integration interval becomes more accurate, improving precision.

[0128] <Embodiment 9>: In the case of three-phase AC <Overview of embodiment 9> The ninth embodiment is an application to three-phase AC based on the first to eighth embodiments which are directed to single-phase AC. Note that the ninth embodiment can be similarly expanded from single phase to other phases (two-phase AC, etc.). <Configuration of embodiment 9> An instantaneous interruption and / or instantaneous sag detection device for three-phase AC can be configured by using three single-phase devices for each phase or for three combinations between two different phases. When detecting instantaneous interruptions and / or instantaneous sags, a detection device can be provided for one phase or one type of two-phase voltage, but more accurate detection can be achieved by providing three types of detection devices corresponding to each of the three phases or three combinations between two different phases. This is because there is a possibility that the wiring of one of the three phases may be broken. [Explanation of symbols]

[0129] Power interruption detection device...0300 AC power supply…0301 Current limiting resistor...0302 2-circuit photocoupler...0303 First photocoupler...0303a Second photocoupler...0303b Microcomputer…0304 Pulse measurement by counter...0305 Zero crossing measurement calculation...0306 Comparison judgment…0307 Comparison time length information retention…0308 Zero cross detection output...0309 Comparison result output...0310

Claims

1. An AC power signal acquisition unit that acquires an AC power signal; a first photocoupler that outputs a signal L when the acquired AC power signal is positive and outputs a signal H when the acquired AC power signal is negative; a second photocoupler that outputs a signal H in response to the acquired AC power signal being positive and outputs a signal L in response to the acquired AC power signal being negative; a counter for counting a signal width, which is an arbitrary time interval of the AC power signal; A power detection device for processing a signal output by a device comprising: a comparative time length information storage unit that stores a plurality of comparative time length information pieces that indicate a predetermined time length to be compared with non-light receiving time length information that indicates a value counted by the counter during a period during which no light receiving signal is acquired from either the first photocoupler or the second photocoupler; a comparison unit that compares the non-light-receiving time length information with a plurality of pieces of comparison time length information; a comparison result output unit that outputs a comparison result for each of the plurality of comparison results in the comparison unit when the comparison result is a predetermined comparison result; "The time difference between the first timing at which the signal of the second photocoupler switches from L to H and the second timing at which the signal of the first photocoupler switches from H to L in the same timing region where the AC power supply signal is inverted from negative to positive" or / and, a time difference acquisition unit that acquires "a time difference between a third timing at which the signal of the second photocoupler switches from H to L and a fourth timing at which the signal of the first photocoupler switches from L to H in the same timing region where the AC power supply signal is inverted positive and negative"; a zero-cross timing acquisition unit that acquires a timing when the voltage of the AC power signal is zero by using a correction time length that is half the time length of the acquired time difference; A correction time length acquisition unit that statistically processes a plurality of acquired time differences to acquire a correction time length. In the correction time length acquisition unit, if the time length obtained by multiplying the time difference acquired by the time difference acquisition unit by 1 / 2 falls outside the range of the predicted maximum and minimum values ​​of the correction time length obtained from the correction time length acquired by statistical processing, the value is excluded from the correction of the zero cross point after half a wavelength, and the same value as the previous time is used as the provisional correction time length. Power sensing device.

2. 2. The power detection device according to claim 1, wherein the first photocoupler and the second photocoupler have substantially equal ON delay times.

3. 3. The power detection device according to claim 1, wherein the first photocoupler and the second photocoupler output an L level when the photocoupler is turned on.

4. 4. The power detection device according to claim 1, wherein the zero-cross timing acquisition unit has a pre-acquisition means for acquiring the zero-cross timing by using the timing at which the signal of the first photocoupler rises from L to H just before the zero-cross timing and a correction time length when the AC power supply signal inverts from positive to negative, and acquiring the zero-cross timing by using the timing at which the signal of the second photocoupler rises from L to H just before the zero-cross timing and a correction time length when the AC power supply signal inverts from negative to positive.

5. an AC power signal acquisition unit that acquires an AC power signal; a first photocoupler that outputs a signal L when the acquired AC power signal is positive and outputs a signal H when the acquired AC power signal is negative; a second photocoupler that outputs a signal H in response to the acquired AC power signal being positive and outputs a signal L in response to the acquired AC power signal being negative; a counter for counting a signal width, which is an arbitrary time interval of the AC power signal; A method of operating a power sensing device that is a computer that processes a signal output by a device comprising: a comparative time length information holding step of holding a plurality of comparative time length information indicating a predetermined time length to be compared with non-light receiving time length information indicating a value counted by the counter during a period during which no light receiving signal is acquired from either the first photocoupler or the second photocoupler; a comparison step of comparing the non-light receiving time length information with a plurality of pieces of comparison time length information; a comparison result output step of outputting a result of each of the comparison results when the comparison results in the comparison step are a predetermined comparison result; "The time difference between the first timing at which the signal of the second photocoupler switches from L to H and the second timing at which the signal of the first photocoupler switches from H to L in the same timing region where the AC power supply signal is inverted from negative to positive" or / and, a time difference acquisition step of acquiring "a time difference between a third timing at which the signal of the second photocoupler switches from H to L and a fourth timing at which the signal of the first photocoupler switches from L to H in the same timing region where the AC power supply signal is inverted positive and negative"; a zero-cross timing acquisition step of acquiring a timing of zero voltage of the AC power signal using a correction time length that is half the time length of the acquired time difference; a corrected time length acquisition step of acquiring a corrected time length by statistically processing a plurality of the acquired time differences; a step of excluding the time length obtained by multiplying the time difference obtained in the time difference obtaining step by half from the range of the predicted maximum and minimum values ​​of the correction time length obtained from the plurality of correction time lengths obtained in the correction time length obtaining step from the time difference ... A method of operating a power sensing device that is a computer having the power sensing device.

6. an AC power signal acquisition unit that acquires an AC power signal; a first photocoupler that outputs a signal L when the acquired AC power signal is positive and outputs a signal H when the acquired AC power signal is negative; a second photocoupler that outputs a signal H in response to the acquired AC power signal being positive and outputs a signal L in response to the acquired AC power signal being negative; a counter for counting a signal width, which is an arbitrary time interval of the AC power signal; A program to be executed by a power detection device which is a computer that processes a signal output by a device comprising: a comparative time length information holding step of holding a plurality of comparative time length information indicating a predetermined time length to be compared with non-light receiving time length information indicating a value counted by the counter during a period during which no light receiving signal is acquired from either the first photocoupler or the second photocoupler; a comparison step of comparing the non-light receiving time length information with a plurality of pieces of comparison time length information; a comparison result output step of outputting a result of each of the comparison results when the comparison results in the comparison step are a predetermined comparison result; "The time difference between the first timing at which the signal of the second photocoupler switches from L to H and the second timing at which the signal of the first photocoupler switches from H to L in the same timing region where the AC power supply signal is inverted from negative to positive" or / and, a time difference acquisition step of acquiring "a time difference between a third timing at which the signal of the second photocoupler switches from H to L and a fourth timing at which the signal of the first photocoupler switches from L to H in the same timing region where the AC power supply signal is inverted positive and negative"; a zero-cross timing acquisition step of acquiring a timing of zero voltage of the AC power signal using a correction time length that is half the time length of the acquired time difference; a corrected time length acquisition step of acquiring a corrected time length by statistically processing a plurality of the acquired time differences; a step of excluding the time length obtained by multiplying the time difference obtained in the time difference obtaining step by half from the range of the predicted maximum and minimum values ​​of the correction time length obtained from the multiple correction time lengths obtained in the correction time length obtaining step from the correction time length obtaining step from the time difference ... A program to be executed by a power detection device that is a computer having the above-mentioned.

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