Three-class AC power supply voltage value and phase sequence detection system
By designing a voltage and phase sequence detection system for three types of AC power supplies, and utilizing components such as Hall voltage sensors and amplifiers, the system achieves real-time acquisition and accurate detection of voltage and phase sequence for the three types of AC power supplies. This solves the problems of inaccurate detection and safety hazards in existing technologies, and provides timely protection and alarm functions.
Patent Information
- Application Number
- CN202422889404.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-26
- Publication Date
- 2026-01-02
- Estimated Expiration
- 2034-11-26
AI Technical Summary
Existing technology cannot simultaneously detect the voltage and phase sequence of three types of AC power sources in real time, and there are safety hazards and measurement inaccuracies.
A three-type AC power supply voltage and phase sequence detection system was designed, including an MCU, a conditioning circuit, and a protection alarm. The system utilizes components such as a Hall voltage sensor, an instrumentation amplifier, and a voltage feedback amplifier, and uses series resistors and capacitors for signal conditioning to achieve real-time acquisition of voltage and phase sequence and protection alarm.
It achieves real-time acquisition of AC220V/50Hz, AC115V/400Hz, and AC380V/50Hz voltage values, accurate detection of AC115V/400Hz and AC380V/50Hz phase sequence, with an acquisition accuracy error of less than 1%, and has timely protection and alarm functions.
Smart Images
Figure CN223756887U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to alternating current source detection technical field especially relates to a three kinds of alternating current source voltage value and phase sequence detection system. BACKGROUND
[0002] With the high -speed development of industrial technology, various large -scale industrial equipment is emerging in an endless stream, and its power supply safety problem is particularly key. At present, the power supply of equipment is mostly AC220V / 50Hz, AC115V / 400Hz, AC380V / 50Hz, and it is needed to confirm whether the voltage of the three power supplies of AC220V / 50Hz, AC115V / 400Hz, AC380V / 50Hz is in the qualified range before the formal power-on of equipment, and the unqualified power supply voltage will cause damage to equipment or lead to the normal work of equipment, wherein AC115V / 400Hz, AC380V / 50Hz also need to detect phase sequence, and the unqualified phase sequence will also affect the normal work of equipment. At the same time, most equipment has the power supply selection of AC220V / 50Hz, AC115V / 400Hz, AC380V / 50Hz, and the current power supply voltage and phase sequence detection are all single mode, and cannot be considered at the same time.
[0003] At present, the voltage detection of three kinds of alternating current sources mostly adopts the multimeter test mode, and this method has three disadvantages at present: (1) needs to measure under voltage, and there is hidden danger for the safety of measurement personnel;(2) can only measure single time, cannot detect voltage value change in real time, and does not have protection alarm function;(3) for AC115V / 400Hz, AC380V / 50Hz, only voltage value can be measured, and phase sequence cannot be measured. INVENTION CONTENTS
[0004] The utility model discloses a three kinds of alternating current source voltage value and phase sequence detection system can collect the voltage value of AC220V / 50Hz, AC115V / 400Hz, AC380V / 50Hz in real time, measures the phase sequence of AC115V / 400Hz, AC380V / 50Hz, can timely protection alarm.
[0005] In order to realize the above object, the technical scheme that the utility model adopts is as follows: a three kinds of alternating current source voltage value and phase sequence detection system, including MCU, AC220V / 50Hz conditioning circuit, AC115V / 400Hz conditioning circuit, AC380V / 50Hz conditioning circuit and protection alarm, the MCU is connected with AC220V / 50Hz conditioning circuit, AC115V / 400Hz conditioning circuit, AC380V / 50Hz conditioning circuit and protection alarm electrically respectively;
[0006] The AC220V / 50Hz conditioning circuit comprises a Hall voltage sensor, an input end of the Hall voltage sensor is connected with an AC220V / 50Hz power source in series with a conditioning resistor R, an output end of the Hall voltage sensor is connected with an input port of an MCU in series with a capacitor C55, the output end of the Hall voltage sensor is also connected with the ground in series with a voltage dividing resistor R55, the input port of the MCU is connected with +3.3V in series with a resistor R75 and is connected with the ground in series with a resistor R74 respectively;
[0007] The AC115V / 400Hz conditioning circuit comprises an instrument amplifier and a voltage feedback amplifier, an input end of the instrument amplifier is connected with an AC115V / 400Hz power source in series with a resistor voltage dividing circuit, an output end of the instrument amplifier is connected with a positive input end of the voltage feedback amplifier in series with a capacitor C13 and a voltage lifting circuit in sequence, an output end of the voltage feedback amplifier is connected with an input port of an MCU and a negative input end of the voltage feedback amplifier respectively;
[0008] The AC380V / 50Hz conditioning circuit is consistent with the AC115V / 400Hz conditioning circuit, and the difference lies in the voltage division of the resistor voltage dividing circuit.
[0009] Preferably, the conditioning resistor R of the AC220V / 50Hz conditioning circuit comprises resistors R53, R54, R69 and R70.
[0010] Preferably, VCC- and VCC+ ports of the Hall voltage sensor are connected with the ground in series with capacitors C34 and C35 respectively, and the VCC- and VCC+ ports of the Hall voltage sensor are connected with -12V and +12V respectively.
[0011] Preferably, the resistor voltage dividing circuit of the AC115V / 400Hz conditioning circuit comprises resistors R13, R14, R15 and R16, two ports of the AC115V / 400Hz power source are connected with two input ends of the instrument amplifier in series with resistors R15 and R16 respectively, and the two input ends of the instrument amplifier are also connected with the ground in series with resistors R13 and R14 respectively.
[0012] Preferably, the voltage lifting circuit comprises resistors R17 and R18, the positive input end of the voltage feedback amplifier is connected with +3.3V in series with resistor R17 and is connected with the ground in series with resistor R18 respectively.
[0013] Preferably, a resistor R37 is connected between two RG ports of the instrument amplifier, two VS ports are connected with +12V and -12V respectively, the two VS ports are connected with the ground in series with capacitors C11 and C12 respectively, and the REF port is connected with the ground.
[0014] Preferably, two VS ports of the voltage feedback amplifier are connected with +12V and -12V respectively, and two VS ports of the voltage feedback amplifier are connected with capacitors C14 and C15 respectively and then grounded.
[0015] Preferably, the Hall voltage sensor is of the model hv25-p.
[0016] Preferably, the instrument amplifier is of the model gf081sz, and the voltage feedback amplifier is of the model cos620arz.
[0017] Preferably, the MCU is an STM32 single-chip microcomputer, and the protection alarm is a display.
[0018] The utility model discloses the beneficial effects are:
[0019] The scheme can collect the voltage value of AC220V / 50Hz, AC115V / 400Hz and AC380V / 50Hz in real time, measure the phase sequence of AC115V / 400Hz and AC380V / 50Hz, and timely protection alarm. BRIEF DESCRIPTION OF DRAWINGS
[0020] In order to more clearly illustrate the technical scheme in the embodiment of the utility model or prior art, the following will briefly introduce the drawing needed to be used in the embodiment or prior art description, and obviously, the drawing in the following description is only some embodiments of the utility model, and for those skilled in the art, other drawings can also be obtained according to these drawings without creative labor.
[0021] Figure 1 It is the circuit principle drawing of the utility model AC220V / 50Hz conditioning circuit.
[0022] Figure 2 It is the circuit principle drawing of the utility model AC115V / 400Hz conditioning circuit.
[0023] Figure 3 It is the circuit principle drawing of the utility model AC380V / 50Hz conditioning circuit.
[0024] Figure 4 It is the waveform diagram of the utility model AC115V / 400Hz power supply.
[0025] Figure 5 It is the waveform diagram of the utility model AC220V / 50Hz power supply.
[0026] Figure 6 It is the work flow chart of the utility model. DETAILED DESCRIPTION
[0027] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.
[0028] This utility model discloses a three-type AC power supply voltage value and phase sequence detection system. The embodiment includes an MCU, an AC220V / 50Hz conditioning circuit, an AC115V / 400Hz conditioning circuit, an AC380V / 50Hz conditioning circuit, and a protection alarm. The MCU is electrically connected to the AC220V / 50Hz conditioning circuit, the AC115V / 400Hz conditioning circuit, the AC380V / 50Hz conditioning circuit, and the protection alarm, respectively.
[0029] The MCU is an STM32 microcontroller, using high performance. Cortex TM The M3 features a 32-bit RISC core with 128KB of flash memory and a clock speed of up to 72MHz. It also includes three internal serial ports and three 12-bit successive approximation analog-to-digital converters to meet data acquisition requirements. The protection alarm is a display.
[0030] like Figure 1 As shown, the AC220V / 50Hz conditioning circuit includes a Hall voltage sensor, model HV25-P, with a rated input current of 10mA and a rated output current I of 25mA. The input terminal of the Hall voltage sensor is connected to the AC220V / 50Hz power supply via a series conditioning resistor R. The conditioning resistor R in the AC220V / 50Hz conditioning circuit includes resistors R53, R54, R69, and R70. The output terminal of the Hall voltage sensor is connected to the MCU input port via a series capacitor C55, and is also grounded via a series voltage divider resistor R55.
[0031] Input voltage U / Input current I * Conditioning resistor R = Back-end voltage U / Output current I * Series voltage resistor R. Input voltage U is the input 220V voltage. The conditioning resistor R is the sum of resistors R53, R54, R69, and R70. The conditioning resistor R = R53 + R54 + R69 + R70. The back-end voltage U is the voltage signal UAC220-ADC entering the MCU. The series voltage resistor R is the voltage divider resistor R55.
[0032] The input ports of the MCU are connected to +3.3V via series resistor R75 and to ground via series resistor R74. The VCC- and VCC+ ports of the Hall voltage sensor are connected to ground via series capacitors C34 and C35, respectively, and the VCC- and VCC+ ports of the Hall voltage sensor are connected to -12V and +12V, respectively.
[0033] The measurement range is adjusted by the front-end R53, R54, R69, R70, and the measurement range U = conditioning resistance R * input current I. The input current I ranges from 0 to 10 mA, so the measurement range U depends on the size of the conditioning resistance R. The maximum value of the measurement range U is set to 400 V, and the conditioning resistance R is obtained by the formula as 40 KΩ. R53, R54, R69, R70 are designed as 10 KΩ chip resistors in 2512 package. The maximum power required by the single chip resistor itself is calculated by the formula power P = input current I2 * single chip resistance R, and the maximum power P is 1 W. According to the manual, the rated power of the chip resistor in 2512 package is 1 W, which can meet the power requirement.
[0034] The Hall voltage sensor is a current following type voltage sensor. The waveform at the output end of the Hall voltage sensor is consistent with the waveform at the input end of the Hall voltage sensor, and is a current signal. The MCU needs to collect a voltage signal ranging from 0 to 3.3 V. The output signal at the rear end of the sensor needs to be conditioned to a voltage value ranging from 0 to 3.3 V. A series resistance R55 is connected to the output pin at the rear end of the Hall voltage sensor through the formula U = IR. To reduce data interference and improve data collection accuracy, a capacitor C55 is connected in series at the front end of the AD collection, which plays a role in blocking AC and passing DC, and can convert the current signal to a voltage signal. Since the output sine wave has positive and negative values, the negative values need to be converted to positive values. The overall waveform is lifted by 1.65 V through R74 and R75. Therefore, the minimum voltage value at the rear end of the sensor cannot be lower than -1.65 V. The minimum value U = output current I * series resistance R is calculated through the formula. The minimum value U is -1.65 V, the output current I is 25 mA, and R55 is calculated to be 66 Ω. Therefore, R55 is selected as a commonly used 51 Ω. The range of UAC220-ADC is 0.375-2.925 V, which meets the collection range of the MCU (0-3.3 V).
[0035] As shown in Figure 5 The AC220V / 50Hz power supply is single-phase alternating current, and there is no need to measure the phase sequence, only the voltage value needs to be measured.
[0036] As shown in Figure 4As shown, the AC115V / 400Hz power supply is a three-phase alternating current. Voltage acquisition, phase sequence detection, and frequency detection are required. Based on the characteristics of three-phase AC power supplies, both the AC115V / 400Hz and AC380V / 50Hz power supplies have three phases (A, B, and C), with a phase difference of 120°, which is 1 / 3 of a cycle. This means that within one cycle, each phase has only one maximum point, and these points do not occur at the same time. By comparing the order in which the highest or lowest points of phases A, B, and C appear within the same cycle, the current phase sequence is determined. Then, by subtracting the time of the lowest point from the time of the highest point of any phase, half a cycle can be obtained. The entire cycle time can then be calculated, and finally, the frequency can be obtained. The specific calculation formula is f = 1 / 2 * (t) up -t douwn ), where t up t is the time when a certain phase peak occurs. down Let f be the time when a certain phase reaches its lowest point, and f be the actual frequency.
[0037] like Figure 2 As shown, the AC115V / 400Hz conditioning circuit includes an instrumentation amplifier and a voltage feedback amplifier. The input terminal of the instrumentation amplifier is connected to the AC115V / 400Hz power supply after a series resistor voltage divider circuit. The output terminal of the instrumentation amplifier is connected to the positive input terminal of the voltage feedback amplifier after a series capacitor C13 and a voltage boost circuit. The output terminal of the voltage feedback amplifier is connected to the input port of the MCU and the negative input terminal of the voltage feedback amplifier, respectively.
[0038] The AC115V / 400Hz conditioning circuit includes resistors R13, R14, R15, and R16. The two ports of the AC115V / 400Hz power supply are connected in series with resistors R15 and R16 respectively and then connected to the two input terminals of the instrumentation amplifier. The two input terminals of the instrumentation amplifier are also connected in series with resistors R13 and R14 respectively and then grounded.
[0039] The voltage boost circuit includes resistors R17 and R18. The positive input terminal of the voltage feedback amplifier is connected to +3.3V after series with resistor R17 and to ground after series with resistor R18.
[0040] The AC 115V / 400Hz voltage value cannot be directly collected, and the high voltage 115V is divided by using a voltage dividing resistor. Since the voltage after voltage division is a sine wave with the X axis as the symmetry axis, the negative half-axis data needs to be converted to a positive value. At this time, a simple voltage lifting circuit composed of R17 and R18 is used to lift the overall waveform data by 1.65V. The resistor voltage dividing circuit composed of R13, R14, R15 and R16 needs to adjust 115V to within 1.65V, otherwise the voltage U after voltage division cannot be all conditioned to a positive value, so R15 and R16 are set to 1MΩ, and R13 and R14 are set to 6.8KΩ, both of which are 0805 packages. According to the formula P=U2 / R, the power on each resistor can also meet the requirements.
[0041] After that, the signal is processed by an instrumentation amplifier, which has the advantages of low noise and low input bias current. The signal from the instrumentation amplifier is connected in series with a capacitor C13, which plays a role in passing AC and blocking DC. Then, through a voltage lifting circuit, the negative half wave is eliminated, and finally, the signal enters a voltage feedback amplifier to eliminate the on-line impedance. The conditioned UC-ADC can directly enter the MCU collection channel.
[0042] The model of the instrumentation amplifier is gf081sz, and the model of the voltage feedback amplifier is cos620arz.
[0043] The two RG ports of the instrumentation amplifier are connected in series with a resistor R37, and the two VS ports are connected to +12V and -12V respectively. The two VS ports are connected in series with capacitors C11 and C12 respectively and then grounded, and the REF port is grounded. The two VS ports of the voltage feedback amplifier are connected to +12V and -12V respectively, and the two VS ports of the voltage feedback amplifier are connected in series with capacitors C14 and C15 respectively and then grounded.
[0044] As shown in Figure 3 , the AC 380V / 50Hz conditioning circuit is consistent with the AC 115V / 400Hz conditioning circuit, except for the voltage division of the resistor voltage dividing circuit.
[0045] As shown in Figure 6 , different work flowcharts are designed according to different power supply characteristics.
[0046] (1) AC 220V / 50Hz power supply, cycle is 20ms, in order to improve data accuracy, the root mean square formula T is the data collection period, V is the instantaneous voltage value, dt is the collection frequency, the effective value of AC is the area of the waveform within one cycle and X axis. In order to reduce data error, the more data collected within one cycle, the more accurate the data obtained. 200 data points are collected continuously within 20 ms cycle, a 100 us timer is set in the software, the data is calculated once for each cycle, the data of 10 cycles is averaged, the total collection cycle is 200 ms, the result refresh cycle is also 200 ms, and the relatively accurate result is obtained. The effective value calculated is brought into the formula: input voltage U / input current I*regulation resistance R=back-end voltage U / output current I*series voltage resistance R, that is, input voltage U / 0.01*40000=back-end voltage U / 0.25*51, so that the value of input voltage U is obtained, which is also the voltage value of AC 220V.
[0047] (2) First, calculate the voltage value of AC 115V / 400Hz power supply. The cycle is 2.5 ms, and the same root mean square formula is used Due to different power supply cycles, the timer is also different. 125 data are collected continuously within 2.5 ms cycle, the software is set to 20 us cycle, the data is calculated once for each cycle, the data of 10 cycles is averaged, and the actual voltage value U is obtained through resistance voltage division ratio U actual voltage value=U effective value / (R14 / (R14+R16)), and the final AC 115V actual voltage value is obtained; then the phase sequence of AC 115V / 400Hz power supply is calculated. As shown in Figure 2 , the time of occurrence of the highest point of each phase A, B and C within one cycle can be used to determine the current phase sequence. The 150 data collected from each phase within the same cycle are sorted and the position is recorded, then the maximum value corresponding to the position number is found after sorting, and the phase sequence is determined by comparing the position number of the maximum value of each phase, and the final phase sequence is A-B-C or A-C-B. Each cycle is collected and judged once, and the detection cycle is 2.5 ms.
[0048] (3) AC 380V / 50Hz power supply, cycle is 20 ms, and the same root mean square formula is used With the same period and calculation method of AC220V / 50Hz power supply, after obtaining the actual effective value, through the front-end resistance voltage division ratio, U actual voltage value = U effective value / (R2 / (R1 + R2)), the actual effective value of the final AC380V can be obtained, and the phase sequence judgment mode is the same as that of AC115V / 400Hz, and the detection period is 20ms. The formula for participating in the calculation is as follows: the voltage unit is "V", the resistance unit is "Ω", the current unit is "A", and the power unit is "W".
[0049] Test conclusion: based on the hardware of the detection module, AC115V / 400Hz, AC380V / 50Hz and AC220V / 50Hz can realize voltage acquisition and phase sequence detection of the corresponding power supply, the test results are shown in Table 1, and the acquisition accuracy error is 1%, and the phase sequence detection is accurate.
[0050] Table 1 test results
[0051]
[0052] It should be noted that the parts not described in detail in the above embodiments are all prior art.
[0053] The above is only a preferred embodiment of the present application, and does not limit the present application in any form. Although the preferred embodiment of the present application has been disclosed as above, it is not intended to limit the present application. Any skilled person in the art can make some changes or modifications to the above disclosed technical content without departing from the technical solution of the present application, and can make equivalent embodiments with equivalent changes. However, any simple modification, equivalent change and modification of the above embodiments according to the technical essence of the present application should be covered within the protection scope of the present application.
Claims
1. A system for detecting the voltage value and phase sequence of a three-phase AC power supply, characterized in that: The AC220V / 50Hz conditioning circuit comprises a Hall voltage sensor, an input end of the Hall voltage sensor is connected with an AC220V / 50Hz power source in series with a conditioning resistor R, an output end of the Hall voltage sensor is connected with an input port of the MCU in series with a capacitor C55, the output end of the Hall voltage sensor is also connected with the ground in series with a voltage dividing resistor R55, the input port of the MCU is connected with +3.3V in series with a resistor R75 and is connected with the ground in series with a resistor R74. The AC115V / 400Hz conditioning circuit comprises an instrument amplifier and a voltage feedback amplifier, an input end of the instrument amplifier is connected with an AC115V / 400Hz power source in series with a resistor dividing circuit, an output end of the instrument amplifier is connected with a positive input end of the voltage feedback amplifier in series with a capacitor C13 and a voltage lifting circuit, an output end of the voltage feedback amplifier is connected with an input port of the MCU and a negative input end of the voltage feedback amplifier. The AC380V / 50Hz conditioning circuit is consistent with the AC115V / 400Hz conditioning circuit, and the difference lies in the voltage division of the resistor dividing circuit. The conditioning resistor R of the AC220V / 50Hz conditioning circuit comprises resistors R53, R54, R69 and R70.
2. The system for detecting the voltage value and phase sequence of a three-phase AC power supply according to claim 1, characterized in that: VCC- and VCC+ ports of the Hall voltage sensor are connected with the ground in series with capacitors C34 and C35, respectively, and are connected with -12V and +12V, respectively.
3. The system for detecting the voltage value and phase sequence of a three-phase AC power supply according to claim 1, characterized in that: The resistor dividing circuit of the AC115V / 400Hz conditioning circuit comprises resistors R13, R14, R15 and R16, two ports of the AC115V / 400Hz power source are connected with two input ends of the instrument amplifier in series with resistors R15 and R16, respectively, and the two input ends of the instrument amplifier are also connected with the ground in series with resistors R13 and R14, respectively.
4. The system for detecting the voltage value and phase sequence of a three-phase AC power supply according to claim 1, characterized in that: The voltage lifting circuit comprises resistors R17 and R18, the positive input end of the voltage feedback amplifier is connected with +3.3V in series with resistor R17 and is connected with the ground in series with resistor R18.
5. The system for detecting the voltage value and phase sequence of a three-phase AC power supply according to claim 1, characterized in that: Two RG ports of the instrument amplifier are connected in series with a resistor R37, two VS ports are connected with +12V and -12V, respectively, the two VS ports are connected with the ground in series with capacitors C11 and C12, respectively, and the REF port is connected with the ground.
6. The system for detecting the voltage value and phase sequence of a three-phase AC power supply according to claim 1, characterized in that: Two VS ports of the voltage feedback amplifier are connected with +12V and -12V, respectively, and the two VS ports of the voltage feedback amplifier are connected with the ground in series with capacitors C14 and C15, respectively.
7. The system for detecting the voltage value and phase sequence of a three-phase AC power supply according to claim 1, characterized in that: The model of the Hall voltage sensor is hv25-p.
8. The system for detecting the voltage value and phase sequence of a three-phase AC power supply according to claim 1, characterized in that: 9. The system for detecting the voltage value and phase sequence of a three-phase AC power supply according to claim 1, characterized in that: The model of the instrument amplifier of the instrument amplifier is gf081sz, and the model of the voltage feedback amplifier is cos620arz.
10. The system for detecting the voltage value and phase sequence of a three-phase AC power supply according to claim 1, characterized in that: The MCU is an STM32 single-chip microcomputer, and the protection alarm is a display.