Alternating current energy detection device

Abstract

The application discloses an alternating current energy detection device, a voltage detection unit, a coupling capacitor formed by being coupled with a measured cable, a first voltage obtained based on an actual voltage and the coupling capacitor, and the first voltage output to a data processing unit; a current detection unit, a measured cable current detected and output to the data processing unit; the data processing unit, the first voltage and the measured cable current received, a first voltage value and a measured cable current value determined; a product of the first voltage value and a measured cable voltage amplification multiple calculated, a measured cable voltage value determined; and the measured cable voltage value and the measured cable current value used to calculate the energy transmitted on the measured cable. The device provided by the application can avoid the installation position of the detection device limited to an electrical connection point, and there is no electrical connection between the detection device and the measured cable. On the premise that the amplitude and phase of the measured voltage and all harmonic information of the measured cable are detected in real time, the safety level of the detection device can be improved, and the cost can be reduced.

Description

Technical Field

[0001] This application relates to the field of electrical energy detection, and in particular to an AC electrical energy detection device. Background Technology

[0002] An AC power detection device detects the AC voltage and current of the cable under test, and calculates the electrical energy transmitted by the cable under test by calculating the AC voltage and current, thereby performing power statistics.

[0003] Generally, the AC voltage detection section of existing AC power detection devices measures the voltage by directly drawing a wire from the cable being tested, for example... Figure 1A and Figure 1B As shown.

[0004] See Figure 1A As shown, electrical connection points for AC voltage detection are specially reserved on the neutral and live wires of the cable under test. After the wires are led out from the electrical connection points, the voltage is reduced by voltage division using resistors, and then the signal is processed and finally input into the ADC (analog to digital converter) to realize AC voltage detection.

[0005] See Figure 1B As shown, existing AC voltage detection methods can also involve leading wires from electrical connection points to a step-down transformer, stepping down the voltage, processing the signal, and finally inputting it into an ADC to achieve AC voltage detection.

[0006] However, both of these methods require dedicated electrical connection points on the cable being tested for AC voltage detection. Therefore, the installation location of the AC power detection device is limited, and various issues such as safety regulations and cost of the electrical connection points must also be considered. Summary of the Invention

[0007] This application provides an AC power detection device that avoids the installation location of the detection device being limited by electrical connection points, and there is no electrical connection between the detection device and the cable under test. It can improve the safety level of the detection device and reduce costs while detecting the amplitude, phase and all harmonics of the measured voltage in real time.

[0008] In a first aspect, this application provides an AC power detection device, comprising: a voltage detection unit, a current detection unit, and a data processing unit; the voltage detection unit forms a coupling capacitor with the cable under test, and is used to obtain a first voltage based on the actual voltage on the cable under test and the coupling capacitor, and output the first voltage to the data processing unit; the current detection unit is used to detect the current of the cable under test and output the current of the cable under test to the data processing unit; the data processing unit is used to receive the first voltage and the current of the cable under test, determine the first voltage value and the current value of the cable under test; calculate the product of the first voltage value and the voltage amplification factor of the cable under test to determine the voltage value of the cable under test; and calculate the electrical energy transmitted on the cable under test based on the voltage value and the current value of the cable under test.

[0009] In view of this, the AC power detection device provided in this application can avoid the problem that the installation location of the AC power detection device is limited by the electrical connection points for AC voltage and current detection. Furthermore, since there is no electrical connection between the AC power detection device and the cable under test, it can improve the safety level of the AC power detection device and reduce its cost while simultaneously detecting the amplitude and phase of the measured voltage and all harmonics of the cable under test in real time.

[0010] In one possible implementation, the voltage detection unit includes: a voltage sensor, an amplification circuit, and a phase-shift compensation circuit. The amplification circuit includes a first input port, a second input port, and a first output port. The first input port is connected to the voltage sensor, the second input port is connected to ground, and the first output port is connected to the phase-shift compensation circuit. The voltage sensor is a conductive cylindrical structure, and the cable under test passes through the voltage sensor, forming a coupling capacitance with the cable under test. The voltage sensor generates an induced voltage based on the actual voltage on the cable under test and the coupling capacitance. The amplification circuit amplifies the induced voltage by a first factor and outputs a second voltage to the phase-shift compensation circuit through the output port. The phase-shift compensation circuit shifts the phase of the second voltage and amplifies it by a second factor, then outputs the first voltage.

[0011] The voltage sensor forms a coupling capacitor with the cable under test, enabling the AC power detection device to detect the actual voltage transmitted on the cable non-contactly. Specifically, an induced voltage is generated on the voltage sensor during actual voltage detection, but this induced voltage is too small to be easily detected by the data processing unit. An amplifier circuit amplifies the induced voltage; this amplifier circuit can be, but is not limited to, an inverting amplifier circuit, a differential amplifier circuit, etc. Furthermore, since the induced voltage is based on capacitive coupling, the phase of the induced voltage generated by the coupling capacitor lags the current by 90°. Therefore, a phase-shifting compensation circuit is needed to further lag the phase of the induced voltage by 90° so that the phase of the voltage output by the phase-shifting compensation circuit matches the phase of the actual voltage on the cable under test. Additionally, the phase-shifting compensation circuit can further amplify the voltage amplified by the amplifier circuit, making it easier for the data processing unit to detect.

[0012] In one possible implementation, the voltage sensor is a closed or open cylindrical structure; the voltage sensor is made of a metallic material.

[0013] To ensure effective capacitive coupling, the voltage sensor can be made of a metallic material, such as copper or aluminum. For example, the voltage sensor can be a copper foil, which can be rolled into a closed or open shape. After the copper foil is placed over the cable under test, a coupling capacitance is generated between the cable and the copper foil. Furthermore, the voltage sensor can also be a polygonal cylindrical structure, such as a square or rectangular cylindrical structure. Alternatively, the voltage sensor can be a non-cylindrical metal bipolar plate structure, with the metal bipolar plates arranged on both sides of the cable under test, allowing the cable to pass through the metal bipolar plates, thereby forming a coupling capacitance with the cable.

[0014] In one possible implementation, the voltage detection unit further includes: a single-pole double-throw switch and an RMS value detection circuit; the single-pole double-throw switch includes a second output port, a ground port, and a preset voltage input port; the single-pole double-throw switch is connected between the second input port and the ground wire, the second output port is connected to the second input port, the preset voltage input port is used to receive the input preset voltage, and the ground port is connected to the ground wire; the amplification circuit includes: a sub-amplifier circuit and a subtraction operation circuit; the sub-amplifier circuit includes a third input port, a fourth input port, and a third output port; the subtraction operation circuit includes a fifth input port, a sixth input port, and a fourth output port; wherein, the first input port and the third input port are connected, the second input port is respectively connected to the fourth input port and the sixth input port, the third output port and the fifth input port are connected, and the fourth output port and the first output port are connected; the first output port is also connected to the RMS value detection circuit; when the second output port is connected to the ground wire, the subtraction operation circuit is used to receive the input preset voltage, and the ground port is connected to the ground wire; the amplification circuit includes: a sub-amplifier circuit and a subtraction operation circuit; the sub-amplifier circuit includes: a sub-amplifier circuit and a subtraction operation circuit; the subtraction operation ... When the grounding port is on, the sub-amplifier circuit amplifies the induced voltage by a first factor and outputs the second voltage to the phase-shift compensation circuit. When the second output port is connected to the preset voltage input port, the sub-amplifier circuit amplifies the difference between the induced voltage and the preset voltage by a first factor to obtain a third voltage. The subtraction circuit calculates the difference between the third voltage and the preset voltage to obtain a fourth voltage and outputs the fourth voltage to the effective value detection circuit through the first output port. The effective value detection circuit receives the fourth voltage and extracts the voltage component of the cable under test and the preset voltage component from the fourth voltage. It then determines the effective value of the cable under test voltage based on the voltage component of the cable under test and the preset voltage component, and sends the effective value of the cable under test voltage to the data processing unit. The data processing unit is specifically used to: receive the effective value of the cable under test voltage; and determine the amplification factor of the cable under test voltage based on the ratio of the effective value of the first voltage to the effective value of the cable under test voltage.

[0015] In certain application scenarios, the coupling capacitor The magnitude of the coupling capacitance will vary due to environmental changes. In actual measurements, it is impossible to guarantee that the position of the cable under test within the voltage sensor will remain constant for each measurement. Furthermore, the cable's sheath thickness is uneven, and its radius is not fixed, making direct measurement of the coupling capacitance difficult. Additionally, environmental changes can alter the dielectric constant of the medium between the voltage sensor and the cable under test; therefore, the coupling capacitance is not a known quantity that can be directly calculated.

[0016] Therefore, after the relative positions of the voltage sensor and the cable under test are fixed, the voltage detection unit needs to be calibrated to indirectly obtain the correspondence between the actual voltage on the cable under test and the first voltage (induced voltage), i.e., the voltage amplification factor of the cable under test. Thus, after each calibration of the voltage detection unit, the voltage value of the cable under test can be obtained based on the first voltage.

[0017] Since the magnitude of the coupling capacitance is difficult to measure directly, it can be equated to the correspondence between the actual voltage and the first voltage. Specifically, after the AC power detection device is installed on the cable under test and its position is fixed, calibration can be performed. After the second output port is connected to the preset voltage input port, the sub-amplifier circuit in the amplifier circuit will simultaneously input a preset voltage with known voltage amplitude and frequency, as well as the induced voltage corresponding to the actual voltage, so that the sub-amplifier circuit outputs a third voltage. This third voltage contains three voltage components: two are components of the preset voltage at different phases, and the other is a component of the actual voltage. Because of the component of the preset voltage at different phases, the subtraction circuit is needed to filter out the component of the two preset voltage components at different phases that is not in phase with the component of the actual voltage, obtaining a fourth voltage. This fourth voltage is then input through the effective value detection circuit to determine the effective value of the actual voltage of the cable under test. After the second output port is connected to the ground wire, the voltage detection unit outputs a first voltage. Based on the first voltage and the effective value of the actual voltage of the cable under test, the correspondence between the effective value of the actual voltage on the cable under test and the effective value of the first voltage is determined, i.e., the voltage amplification factor of the cable under test, thereby eliminating the influence caused by changes in the coupling capacitance. In the above scenario, after extracting the voltage component of the cable under test and the preset voltage component, the effective value detection circuit can calculate an intermediate value. Different structures of the effective value detection circuit output different intermediate values, but the intermediate value and the effective value of the voltage of the cable under test all have a linear relationship. Those skilled in the art should be familiar with various structures of the effective value detection circuit.

[0018] In one possible implementation, the device further includes a power supply unit; the power supply voltage is used to power the voltage detection unit and the data processing unit.

[0019] To ensure the normal operation of the AC power detection device, the power supply unit can be powered by an external power source. The external power source can power the voltage detection unit, the current detection unit, and the data processing unit in the AC power detection device. However, finding a power source from the outside will result in a more complex power supply method. Furthermore, the AC power detection device is limited by the location of the power source and can only perform detection near the power source. It can be powered by an internal battery, but the battery has a lifespan issue and needs to be replaced repeatedly.

[0020] In view of this, in order to solve the problem that the AC power detection device is limited by the location of the power supply or the need for repeated battery replacements, in one possible implementation, the power supply unit includes: a current transformer, a filter and rectifier circuit, and a power management unit; the current transformer is used to generate an induced current based on the actual current on the cable under test, and output the induced current to the filter and rectifier circuit; the filter and rectifier circuit is used to filter and rectify the induced current to obtain a power supply current; the power management unit is used to use the power supply current to supply power to the voltage detection unit, the current detection unit, and the processing unit respectively.

[0021] To ensure that the installation location of the entire AC power detection device is unrestricted, the power supply unit on the AC power detection device can also be designed to draw power in a non-contact manner, so that the AC power detection device is also not limited by the location of the external power source and can work normally in any position of the cable under test.

[0022] In one possible implementation, the current transformer is a toroidal iron core with at least one turn of coil wound around it. The toroidal iron core can be closed or open, and the at least one turn of coil is used to connect to the rectifier and filter circuit. The current transformer operates on a similar principle to a commonly used current transformer, but the specific parameters differ, such as the number of turns of the coil wound around the toroidal iron core. Different numbers of turns result in different induced currents, allowing for different coil turns ratios to be set according to different power supply requirements.

[0023] In one possible implementation, the power management unit is a DC / DC circuit. This DC / DC conversion circuit can be composed of devices such as switching transistors, diodes, inductors, and capacitors. The operating state of the DC / DC conversion circuit can be achieved by adjusting the operating states of these devices. Specifically, the operating state of the DC / DC conversion circuit can be: converting received electrical energy into a voltage suitable for the voltage detection unit, the current detection unit, and the data processing unit. Specifically, the switching transistor in the DC / DC conversion circuit can be a metal-oxide-semiconductor (MOS) transistor, a bipolar junction transistor (BJT), or other devices capable of switching functions. Furthermore, the power management unit may also include a battery module. The DC / DC conversion circuit converts the received electrical energy and outputs it to the battery module, at which point the DC / DC conversion circuit is in a charging state. When the voltage detection unit, the current detection unit, and the data processing unit are operating, the electrical energy stored in the battery module is converted into a voltage suitable for the voltage detection unit, the current detection unit, and the data processing unit for output, at which point the DC / DC conversion circuit is in a discharging state. By designing a battery unit in the power supply unit, the power supply unit of the AC power detection device can temporarily store electrical energy, and can supply power to the AC power detection device when voltage detection is required.

[0024] Secondly, this application provides an AC voltage detection device, the device comprising a voltage detection unit and a data processing unit; the voltage detection unit forms a coupling capacitor with the cable under test, and is used to obtain a first voltage based on the actual voltage on the cable under test and the coupling capacitor, and output the first voltage to the data processing unit; the data processing unit is used to receive the first voltage and determine the first voltage value; calculate the product of the first voltage value and the voltage amplification factor of the cable under test, and determine the voltage value of the cable under test.

[0025] In one possible implementation, the voltage detection unit includes: a voltage sensor, an amplification circuit, and a phase-shift compensation circuit. The amplification circuit includes a first input port, a second input port, and a first output port. The first input port is connected to the voltage sensor, the second input port is connected to ground, and the first output port is connected to the phase-shift compensation circuit. The voltage sensor is a conductive cylindrical structure, and the cable under test passes through the voltage sensor, forming a coupling capacitance with the cable under test. The voltage sensor generates an induced voltage based on the actual voltage on the cable under test and the coupling capacitance. The amplification circuit amplifies the induced voltage by a first factor and outputs a second voltage to the phase-shift compensation circuit through the output port. The phase-shift compensation circuit shifts the phase of the second voltage and amplifies it by a second factor, then outputs the first voltage.

[0026] In one possible implementation, the phase-shift compensation circuit is specifically used to lag the phase of the second voltage by 90°.

[0027] In one possible implementation, the voltage sensor is a closed or open cylindrical structure; the voltage sensor is made of a metallic material.

[0028] In one possible implementation, the voltage detection unit further includes: a single-pole double-throw switch and an RMS value detection circuit; the single-pole double-throw switch includes a second output port, a ground port, and a preset voltage input port; the single-pole double-throw switch is connected between the second input port and the ground wire, the second output port is connected to the second input port, the preset voltage input port is used to receive the input preset voltage, and the ground port is connected to the ground wire; the amplification circuit includes: a sub-amplifier circuit and a subtraction operation circuit; the sub-amplifier circuit includes a third input port, a fourth input port, and a third output port; the subtraction operation circuit includes a fifth input port, a sixth input port, and a fourth output port; wherein, the first input port and the third input port are connected, the second input port is respectively connected to the fourth input port and the sixth input port, the third output port and the fifth input port are connected, and the fourth output port and the first output port are connected; the first output port is also connected to the RMS value detection circuit; when the second output port is connected to the ground wire, the subtraction operation circuit is used to receive the input preset voltage, and the ground port is connected to the ground wire; the amplification circuit includes: a sub-amplifier circuit and a subtraction operation circuit; the sub-amplifier circuit includes: a sub-amplifier circuit and a subtraction operation circuit; the subtraction operation ... When the grounding port is on, the sub-amplifier circuit amplifies the induced voltage by a first factor and outputs the second voltage to the phase-shift compensation circuit. When the second output port is connected to the preset voltage input port, the sub-amplifier circuit amplifies the difference between the induced voltage and the preset voltage by a first factor to obtain a third voltage. The subtraction circuit calculates the difference between the third voltage and the preset voltage to obtain a fourth voltage and outputs the fourth voltage to the effective value detection circuit through the first output port. The effective value detection circuit receives the fourth voltage and extracts the voltage component of the cable under test and the preset voltage component from the fourth voltage. It then determines the effective value of the cable under test voltage based on the voltage component of the cable under test and the preset voltage component, and sends the effective value of the cable under test voltage to the data processing unit. The data processing unit is specifically used to: receive the effective value of the cable under test voltage; and determine the amplification factor of the cable under test voltage based on the ratio of the effective value of the first voltage to the effective value of the cable under test voltage.

[0029] In one possible implementation, the device further includes a power supply unit; the power supply voltage is used to power the voltage detection unit and the data processing unit.

[0030] In one possible implementation, the power supply unit includes: a current transformer, a filter and rectifier circuit, and a power management unit; the current transformer is used to generate an induced current based on the current on the cable under test, and output the induced current to the filter and rectifier circuit; the filter and rectifier circuit is used to filter and rectify the induced current to obtain a power supply current; the power management unit is used to use the power supply current to supply power to the voltage detection unit and the processing unit respectively.

[0031] In one possible implementation, the current transformer is a toroidal iron core with at least one turn of coil wound around it. The toroidal iron core may be a closed or open structure, and the at least one turn of coil is used to connect to the rectifier and filter circuit. The power management unit is a DC-to-DC / DC converter circuit.

[0032] Thirdly, this application provides an AC power detection method, the method comprising: receiving a first voltage and a current of a cable under test, determining the first voltage value and the current value of the cable under test; calculating the product of the first voltage value and the voltage amplification factor of the cable under test, determining the voltage value of the cable under test; and calculating the electrical energy transmitted on the cable under test based on the voltage value of the cable under test and the current value of the cable under test.

[0033] In one possible implementation, the method further includes: receiving the effective value of the voltage of the cable under test; and determining the voltage amplification factor of the cable under test based on the ratio of the effective value of the first voltage to the effective value of the voltage of the cable under test.

[0034] Fourthly, this application provides an AC voltage detection method, the method comprising: receiving a first voltage and determining a first voltage value; calculating the product of the first voltage value and the voltage amplification factor of the cable under test, and determining the voltage value of the cable under test.

[0035] In one possible implementation, the method further includes: receiving the effective value of the voltage of the cable under test; and determining the voltage amplification factor of the cable under test based on the ratio of the effective value of the first voltage to the effective value of the voltage of the cable under test.

[0036] The beneficial effects of each possible design in aspects two through four of this application can be referred to in aspect one, and will not be repeated here. Attached Figure Description

[0037] Figure 1A This is a schematic diagram of a circuit structure for detecting voltage using a resistor voltage divider method;

[0038] Figure 1B This is a schematic diagram of a circuit structure for detecting voltage using a step-down transformer;

[0039] Figure 2 This is a schematic diagram of an AC power detection device.

[0040] Figure 3A This is a schematic diagram of the structure of a voltage detection unit;

[0041] Figure 3B This is a schematic diagram of the structure of a voltage sensor;

[0042] Figure 3CThis is a schematic diagram of an inverting amplifier circuit;

[0043] Figure 3D This is a schematic diagram of a phase-shift compensation circuit;

[0044] Figure 4A This is a schematic diagram of another voltage detection unit.

[0045] Figure 4B This is a schematic diagram of an amplifier circuit.

[0046] Figure 4C A flowchart illustrating the steps for detecting the voltage of the cable under test.

[0047] Figure 5A This is a schematic diagram of a structure that utilizes an external power supply.

[0048] Figure 5B This is a schematic diagram of a battery-powered structure;

[0049] Figure 5C This is a schematic diagram of the installation structure of a power supply unit;

[0050] Figure 5D This is an equivalent schematic diagram of a power supply unit;

[0051] Figure 6 This is a schematic diagram of an AC voltage detection device. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. The AC power detection device provided in the embodiments of this application can be used to measure the electrical energy transmitted on cables. These cables are used for power transmission on various types of power grids, such as urban power grids, photovoltaic power grids, microgrids, residential power grids, industrial power grids, etc. The electrical energy transmitted by these power grids may be high-frequency AC or low-frequency AC, and may be high-voltage or low-voltage. The specific type of power grid determines the electrical energy transmitted on the cable, and this application does not impose many limitations on this.

[0053] It should be noted that in the description of this application, "at least one" refers to one or more, where "multiple" refers to two or more. Therefore, in the embodiments of this application, "multiple" can also be understood as "at least two". "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone. Additionally, the character " / ", unless otherwise specified, generally indicates that the preceding and following related objects have an "or" relationship. Furthermore, it should be understood that in the description of this application, words such as "first" and "second" are used only for descriptive purposes and should not be construed as indicating or implying relative importance or order.

[0054] The following explanations will first clarify some of the terms used in the embodiments of this application, so that those skilled in the art can easily understand them.

[0055] (1) Production compliance level: Safety regulations are the safety requirements for products in product certification, including the safety requirements for product components and the safety requirements after the product is assembled into a finished product. Through simulated use methods and a series of tests, the product is assessed for potential hazards such as electric shock, fire, mechanical injury, heat injury, chemical injury, radiation injury, and food hygiene hazards that may occur under normal or abnormal use.

[0056] (2) Capacitive coupling, also known as electric field coupling or electrostatic coupling, is a coupling method caused by the presence of distributed capacitance. Specifically, in a DC circuit, a capacitor is equivalent to an open circuit, and current cannot pass through it; while in an AC circuit, as the voltage at one end of the capacitor gradually increases, the charge accumulated on the electrode plate connected to that end also gradually increases, and as the voltage gradually decreases, the charge accumulated on the corresponding electrode plate also gradually decreases. Throughout this process, no current actually flows through the capacitor, but it appears as if current is flowing through it. Therefore, in an AC circuit, a coupling capacitor can approximate the transfer of current from one stage to the next in this way.

[0057] To facilitate understanding of the AC power detection device provided in this application embodiment, its application scenario is first introduced below. The AC power detection device can detect the AC voltage and current of the cable under test, and calculate the electrical energy transmitted by the cable for power statistics. Generally, the AC voltage detection part of existing AC power detection devices measures the voltage directly from the electrical connection point of the cable under test. Specifically, after leading out the electrical connection point, the cable under test can be connected to a voltage divider resistor circuit for voltage reduction before signal processing; alternatively, after leading out the electrical connection point, the cable under test can be connected to a step-down transformer, and after voltage reduction, signal processing is performed to finally obtain the AC voltage value on the cable under test.

[0058] However, using the aforementioned method of detecting power by leading out electrical connection points limits the detection location of the AC power detection device to the electrical connection points led out from the neutral and live wires of the cable under test. Furthermore, the safety and insulation requirements of the cable after setting up these connection points must be considered. In addition, this method necessitates the use of a resistor divider circuit or a step-down transformer to reduce the voltage on the cable under test for easier detection. Therefore, these circuits increase the size and cost of the AC power detection device, causing inconvenience for testing personnel.

[0059] Therefore, further improvements are needed for AC power detection devices to enhance their safety rating, simplify them, reduce costs, and enable testing personnel to detect AC power through non-contact electrical connections. The following embodiments use single-phase voltage detection as an example; however, the AC power detection devices described in these embodiments can also be used in three-wire and two-wire scenarios. In these scenarios, the usage of the AC power detection devices is simply a simplified combination of single-phase methods, and will not be elaborated further here. See also... Figure 2 As shown, Figure 2 An AC power detection device 10 is provided, comprising: a voltage detection unit 11, a current detection unit 12, and a data processing unit 13.

[0060] The following describes the function of each unit in the device during the process of detecting the electrical energy transmitted by the cable under test:

[0061] The voltage detection unit 11 forms a coupling capacitor with the cable under test, and is used to obtain a first voltage based on the actual voltage on the cable under test and the coupling capacitor, and output the first voltage to the data processing unit 13; the current detection unit 12 is used to detect the current of the cable under test and output the current of the cable under test to the data processing unit 13; the data processing unit 13 is used to receive the first voltage and the current of the cable under test, determine the first voltage value and the current value of the cable under test; calculate the product of the first voltage value and the voltage amplification factor of the cable under test to determine the voltage value of the cable under test; and calculate the electrical energy transmitted on the cable under test based on the voltage value and the current value of the cable under test.

[0062] Specifically, the voltage detection unit 11 is used to detect the voltage of the cable under test. The voltage detection is performed by a voltage sensor rather than by drawing the voltage directly from the cable, which can greatly improve the safety level of the AC power detection device. The specific voltage detection method can be found in the description in the following embodiments.

[0063] The current detection unit 12 may include a current transformer (CT), which is an instrument that converts a large primary current into a small secondary current for measurement based on the principle of electromagnetic induction. The current transformer consists of a closed iron core and windings. Its primary winding has very few turns (in this application, the primary winding is a cable). It is connected in series in the line where the current to be measured, and the current transformer is placed on the cable under test. The principle of electromagnetic induction is used to detect the current in the cable under test. Specifically, a magnetic field is generated around the cable under test. After the current transformer is placed on the cable under test, the coil in the current transformer will generate an induced current due to the magnetic field of the cable under test. After amplifying the induced current, the current of the cable under test can be obtained.

[0064] The data processing unit 13 may be a processor or controller, such as a general-purpose central processing unit (CPU), a general-purpose processor, a digital signal processing unit (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It can implement or execute various exemplary logic blocks, modules, and circuits described in conjunction with the disclosure of this application. The aforementioned processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc., and the data processing unit 13 may further include an analog-to-digital converter (ADC) for converting the analog quantities input to the voltage detection unit 11 and the current detection unit 12 into digital quantities.

[0065] The data processing unit 13, after receiving the first voltage and the current of the cable under test, uses the ADC to determine the first voltage value and the current value of the cable under test, and calculates the product of the first voltage value and the cable voltage amplification factor to obtain the voltage value of the cable under test. During voltage detection by the voltage detection unit 11, the actual voltage on the cable under test is reduced by a certain proportion, and the first voltage is output. After amplifying the first voltage by the cable voltage amplification factor, the voltage value of the cable under test can be obtained. Based on the voltage value and current value of the cable under test, the transmitted electrical power on the cable under test can be determined, and further, based on the transmission time and transmitted electrical power, the electrical energy transmitted on the cable under test can be determined.

[0066] In one possible implementation, see [reference] Figure 3A As shown, Figure 3A This is a schematic diagram of a voltage detection unit. The voltage detection unit 11 includes: a voltage sensor 301, an amplifier circuit 302, and a phase-shift compensation circuit 303. The amplifier circuit 302 includes a first input port 31, a second input port 32, and a first output port 33. The first input port 31 is connected to the voltage sensor 301, the second input port 32 is connected to ground, and the first output port 33 is connected to the phase-shift compensation circuit 303.

[0067] The voltage sensor 301 is a cylindrical structure capable of conducting electricity. The cable under test passes through the voltage sensor 301, and the voltage sensor 301 and the cable under test form a coupling capacitance. The voltage sensor 301 is used to generate an induced voltage based on the actual voltage on the cable under test and the coupling capacitance.

[0068] The amplifier circuit 302 is used to amplify the induced voltage by a first factor and output a second voltage to the phase-shift compensation circuit through the output port.

[0069] The phase-shifting compensation circuit 303 is used to phase-shift the second voltage and amplify it by a second factor to output the first voltage.

[0070] In one possible implementation, the voltage sensor 301 is a closed or open cylindrical structure; the voltage sensor is made of a metallic material, such as copper or aluminum. For specific details, please refer to [reference needed]. Figure 3B As shown, Figure 3B This is a schematic diagram of a voltage sensor. The voltage sensor 301 is a copper foil, which can be rolled into a closed or open shape. After the copper foil is placed on the cable under test, a coupling capacitance is generated between the cable under test and the copper foil. Furthermore, in actual AC power detection scenarios, changes in external environmental conditions such as the position of the cable under test within the voltage sensor 301 and the cable thickness can cause… The changes are difficult to measure.

[0071] The voltage sensor 301 can also be non- Figure 3B The cylindrical structure shown can also be a polygonal cylindrical structure, such as a square cylindrical structure, a rectangular cylindrical structure, etc. Furthermore, the voltage sensor can also be a non-cylindrical metal bipolar plate structure. Specifically, the metal bipolar plate can be arranged on both sides of the cable under test, with the cable passing through the metal bipolar plate, thereby forming a coupling capacitance with the cable under test. .

[0072] A coupling capacitance is formed between the voltage sensor 301 and the cable under test. Subsequently, the AC voltage on the cable under test and the coupling capacitor are coupled together to form the induced voltage input amplifier circuit 302. However, since the magnitude of the induced voltage is too small, it is not easily recognized and detected by the ADC in the data processing unit 13. Therefore, the amplifier circuit 302 is needed to amplify the induced voltage to obtain a second voltage. The amplifier circuit can be, but is not limited to, inverting amplifier circuits, differential amplifier circuits, etc. Here, we take an inverting amplifier circuit as an example. (See attached image / reference). Figure 3C As shown, Figure 3C This is a schematic diagram of an inverting amplifier circuit. The first amplification factor of the inverting amplifier circuit is related to the feedback resistor R0 in the inverting amplifier circuit. The larger the feedback resistor R0 is, the larger the amplification factor is. Those skilled in the art should know this, so it will not be elaborated here.

[0073] The phase-shift compensation circuit 303 is used to convert the second voltage The voltage is phase-shifted and amplified by a second factor, ultimately outputting the first voltage. See also Figure 3D As shown, Figure 3D This is a schematic diagram of a phase-shift compensation circuit, wherein the phase-shift compensation circuit 303 converts the second voltage... The function of amplifying the second voltage factor is similar to that of amplifying the induced voltage by the first factor; it further amplifies the second voltage, making it easier for the ADC in the data processing unit 13 to recognize. The second amplification factor of the amplification circuit 302 is related to the feedback resistors R1, R2, and R3 in the inverting amplification circuit. Furthermore, since the induced voltage is obtained through capacitive coupling, based on the properties of the coupling capacitor—voltage is directly proportional to charge and inversely proportional to capacitance—voltage is the result of charge accumulation. Therefore, voltage will not change abruptly, while current can change abruptly. The current phase leads the voltage. In an AC steady-state circuit, the voltage phase after the capacitor lags the current phase by 90°. The induced voltage lags the actual voltage on the measured cable by 90°, thus amplifying the induced voltage to obtain the second voltage. The phase will also lag by 90°. Therefore, in order to ensure that the phase information of the actual voltage on the cable under test is not lost, it is necessary to amplify the second voltage obtained from the induced voltage. The phase is compensated to restore the phase information of the actual voltage. As an optional implementation, the phase-shift compensation circuit is specifically used to compensate for the phase shift through a capacitor. Lag the phase of the second voltage by 90°, because the second voltage The second voltage is obtained by inverting the induced voltage. Therefore, after being amplified by the inverting amplifier circuit, the phase of the second voltage changes by 180° compared to the induced voltage, while the phase of the induced voltage lags behind the actual voltage by 90°. Therefore, the capacitor in the phase-shift compensation circuit... By delaying the phase of the second voltage by 90° again, the first voltage output by the phase-shift compensation circuit can be... The phase of the voltage is adjusted to match the phase of the actual voltage on the cable under test.

[0074] In summary, given the first multiple, the second multiple, and the first voltage... Then, the magnitude of the induced voltage can be calculated by reverse deduction, and based on the correspondence between the induced voltage and the actual voltage on the cable under test, the voltage value of the cable under test can be determined. This correspondence is related to the coupling capacitance. The size is related to this, as those skilled in the art should know, and will not be elaborated upon here. When the coupling capacitor... When considered as a fixed value, the correspondence between the induced voltage and the actual voltage on the cable under test can be obtained, thereby determining the voltage value of the cable under test.

[0075] However, in certain detection scenarios, the coupling capacitor The size of the coupling capacitance will vary due to changes in the environment. Refer to the following formula. The size of the coupling capacitance depends on the following parameters:

[0076]

[0077] in, For coupling capacitors, The dielectric constant of the medium. Let be the area of ​​the metal plate. This refers to the spacing between the metal plates.

[0078] Continue reading Figure 3B As shown, the voltage sensor 301 in this embodiment can be a conductive cylindrical structure; therefore, the spacing between the metal plates... The position of the cable under test in the voltage sensor 301 is related to the position of the cable under test. However, in actual measurements, it cannot be guaranteed that the position of the cable under test in the voltage sensor 301 will remain constant for each measurement. Furthermore, due to the uneven thickness of the outer sheath of the cable under test and the fact that the radius of the cable under test is not fixed, the coupling capacitance... The magnitude of the capacitance is difficult to measure directly. Furthermore, environmental changes can cause variations in the dielectric constant of the medium between the voltage sensor 301 and the cable under test, thus affecting the coupling capacitance. It is not a known quantity that can be directly measured. For the above reasons, after the positions of the voltage sensor and the cable under test are fixed, the voltage detection unit 11 needs to be calibrated to avoid issues caused by coupling capacitance. This addresses the issue of inaccurate voltage measurement of the tested cable due to variations, ultimately enabling the direct determination of the actual voltage on the tested cable and the first voltage. The correspondence between (induced voltages). Thus, after each calibration of the voltage detection unit 11, based on the first voltage... The voltage value of the cable under test can then be obtained.

[0079] Optional, see below Figure 4A The diagram shows a different voltage detection unit 11. This voltage detection unit 11 further includes a single-pole double-throw switch 304 and an RMS detection circuit 305. The single-pole double-throw switch 304 includes a second output port 39, a ground port 40, and a preset voltage input port 41. The single-pole double-throw switch 304 is connected between the second input port 32 and the ground wire. The second output port 39 is connected to the second input port 32. The preset voltage input port 41 is used to receive the input preset voltage. The grounding port is connected to the ground wire;

[0080] The effective value detection circuit 305 is used to receive the fourth voltage. And extract the fourth voltage respectively. The system reads the voltage component of the cable under test and the preset voltage component, determines the effective value of the voltage of the cable under test based on the voltage component of the cable under test and the preset voltage component, and sends the effective value of the voltage of the cable under test to the data processing unit 13.

[0081] Among them, Figure 3A Based on the amplifier circuit shown, refer to Figure 4B The diagram shown is a schematic of the internal structure of another amplifier circuit. The amplifier circuit 302 may include: a sub-amplifier circuit 3021 and a subtraction operation circuit 3022.

[0082] The sub-amplifier circuit 3021 can be an inverting amplifier circuit, and the sub-amplifier circuit 3021 includes a third input port 34, a fourth input port 35, and a third output port 38; the subtraction operation circuit 3022 includes a fifth input port 36, a sixth input port 37, and a fourth output port 42; wherein, the first input port 31 is connected to the third input port 34, the second input port 32 is connected to the fourth input port 35 and the sixth input port 37, the third output port 38 is connected to the fifth input port 36, and the fourth output port 42 is connected to the first output port 33; the first output port 33 is also connected to the RMS detection circuit 305;

[0083] When the second output port 39 is connected to the ground port 40, the sub-amplifier circuit 3021 is used to amplify the induced voltage by a first factor, and to amplify the second voltage... The output is sent to the phase-shift compensation circuit; when the second output port is connected to the preset voltage input port, the sub-amplifier circuit is used to differentially amplify the induced voltage and the preset voltage by a first factor to obtain a third voltage. The subtraction circuit 3022 is used to calculate the third voltage. The difference between the voltage and the preset voltage is used to obtain the fourth voltage. A fourth voltage is output to the effective value detection circuit 305 through the first output port. ;

[0084] Continue to refer to Figure 2 As shown, the data processing unit 13 is further specifically used for: receiving the effective value of the voltage of the cable under test; and based on the first voltage... The ratio of the effective value of the voltage to the effective value of the voltage of the cable under test is used to determine the voltage amplification factor of the cable under test.

[0085] Among them, due to the coupling capacitor The magnitude of this voltage can be uncertain due to environmental changes. Therefore, this embodiment introduces a preset voltage. skip determining the coupling capacitance in this way The process of determining the magnitude directly determines the actual voltage on the cable under test and the first voltage. The corresponding relationship of (induced voltage). Specifically, but not limited to, it can be calculated using the following methods:

[0086] See Figure 4B As shown, when the second output port 39 is connected to the preset voltage input port 41, the sub-amplifier circuit 3021 receives the preset voltage through the fourth input port 35. Furthermore, the subtraction circuit 3022 can also input the preset voltage through the sixth input port 37. The sub-amplifier circuit 3021 differentially amplifies the induced voltage and the preset voltage to obtain a third voltage. The subtraction circuit 3022 is used to calculate the third voltage. The difference between the voltage and the preset voltage is used to obtain the fourth voltage. A fourth voltage is output to the effective value detection circuit 305 through the first output port. As an optional implementation, the subtraction circuit 3022 can be an instrumentation operational amplifier circuit with a gain of G.

[0087] Specifically, if the actual voltage on the cable under test is Then the third voltage output through the sub-amplifier circuit for: ,in, For the preset voltage angular frequency, The actual voltage on the cable under test angular frequency.

[0088] It can be seen that the third voltage There are three voltage components, two of which are components of the preset voltage at different phases: as well as Another is the actual voltage on the cable being tested. Quantity: The concept of this application embodiment is to extract the two components separately through the effective value detection circuit 305. and The intermediate value X is determined, and the effective value of the voltage of the cable under test is determined based on the intermediate value X. The output of the phase-shift compensation circuit 303 at this time... and the actual voltage of the cable under test. The effective value is used to determine the effective value of the actual voltage on the tested cable and its comparison with the first voltage. The correspondence between the effective values ​​of (induced voltage) and the voltage amplification factor of the cable under test is used to eliminate coupling capacitance. The impact of the change is determined based on the voltage amplification factor of the cable under test and the first voltage detected in real time. The amplitude, phase and other information of the voltage of the tested cable are determined, and the harmonic information in the voltage of the tested AC cable is not lost.

[0089] However, since the third voltage contains components of the preset voltage at different phases, it is necessary to... Figure 4BThe subtraction circuit 3022 in the above-mentioned subtraction circuit will subtract the... After component sieving, the fourth voltage is obtained. .

[0090] The fourth voltage The input is given to the RMS detection circuit. The fourth voltage... .

[0091] The effective value detection circuit 305 can extract the fourth voltage. The voltage components of the cable under test described in the text and the preset voltage component The effective value of the voltage of the cable under test is determined based on the voltage component of the cable under test and the preset voltage component, and the effective value of the voltage of the cable under test is sent to the data processing unit 13.

[0092] In the above scenario, Figure 4A After extracting the voltage component of the cable under test and the preset voltage component, the effective value detection circuit 305 can calculate an intermediate value X based on the voltage component of the cable under test and the preset voltage component. The intermediate value X output by the effective value detection circuit 305 with different structures is different, but the intermediate value X has a linear relationship with the effective value of the voltage of the cable under test. The effective value detection circuit 305 can be any structure known to those skilled in the art, and no further limitations are made here.

[0093] To determine the linear relationship between the intermediate value X and the effective value of the voltage of the cable under test, the AC power detection device can be pre-tested before actual use. Figure 4B The second output port 39 of the single-pole double-throw switch 304 is connected to the preset voltage input port 41, and multiple cables with known amplitude and frequency are detected to obtain multiple sets of data (effective value ~ median value X of the cables with known amplitude and frequency). Based on the multiple sets of data, the linear relationship between the median value X output by the effective value detection circuit 305 and the effective value of the cable can be calculated: ,in, and The coefficients represent the linear relationship. The effective value of the cable is known for both amplitude and frequency. A linear relationship is established between the intermediate value X and the effective value of the cable. The actual cable under test is then fitted into the AC power detection device. Based on the intermediate value X output at this time, the effective value of the cable voltage is determined and sent to the data processing unit 13.

[0094] Scenario during actual measurement: When Figure 4BWhen the second output port 39 of the single-pole double-throw switch 304 is connected to the ground port 40, the sub-amplifier circuit 3021 amplifies the induced voltage by a first factor, and the second voltage... The input to the subtraction circuit 3022 is adjusted, but at this time, the sixth input port 37 of the subtraction circuit 3022 is grounded. Therefore, the subtraction circuit 3022 still outputs the second voltage. , the second voltage The input phase-shift compensation circuit 303 performs phase shifting and amplifies the voltage by a second factor, ultimately outputting the first voltage. Based on the effective value of the voltage of the cable under test and the first voltage... The ratio is used to determine the voltage amplification factor of the cable under test. The data processing unit 13 then uses the voltage amplification factor of the cable under test and the first voltage detected in real time to determine the voltage amplification factor. The voltage value of the cable under test is determined.

[0095] In summary, see the following: Figure 4C The flowchart described above illustrates the method for detecting the voltage of the cable under test using the voltage detection unit 11, which mainly includes the following steps in this embodiment:

[0096] S401, connect the second output port 39 to the preset voltage input port 41, detect the voltage of multiple cables with known amplitude and frequency, and determine the linear relationship between the intermediate value X and the effective value of the voltage of the cable under test. .

[0097] S402, In actual measurement, the AC power detection device 10 is first installed on the cable under test, and the relative positions of the cable under test and the AC power detection device are fixed. Then, the second output port 39 is kept connected to the preset voltage input port 41 to obtain the intermediate value X. Based on the linear relationship of the effective value of the voltage of the cable under test, the effective value of the cable under test is determined. .

[0098] S403, connect the second output port 39 to the ground port 40, and the phase-shift compensation circuit in the voltage detection unit 11 outputs a first voltage. Based on the effective value of the cable under test and the first voltage The ratio of the two values ​​is used to determine the voltage amplification factor of the cable under test.

[0099] S404, based on the voltage amplification factor of the cable under test and the first voltage detected in real time. Determine the voltage value of the cable being tested.

[0100] It should be noted that the AC power detection device may also include the power supply unit. In one possible embodiment, the power supply unit can be an external power supply, which can supply power to the voltage detection unit 11, the current detection unit 12, and the data processing unit 13 in the AC power detection device 10. (See reference...) Figure 5A The diagram shown illustrates how an AC power detection device can be powered by an external power source. However, relying on an external power source leads to a more complex power supply configuration, and the AC power detection device is limited by the location of the external power source, meaning it can only perform detection near the source. Alternatively, refer to... Figure 5B As shown, the power supply unit can also contain a battery built into the AC power detection device, but the built-in battery has a lifespan issue and needs to be replaced repeatedly.

[0101] In other embodiments, to address the issue of the AC power detection device 10 being limited by the location of the external power supply or the need for repeated replacement of the built-in battery, this application also provides an alternative power supply method, which will be described in detail below. (Continue reading...) Figure 2 As shown, the AC power detection device may further include a power supply unit 14, see reference. Figure 5C As shown, Figure 5C This is a schematic diagram of the installation of a power supply unit 14, which includes: a current transformer 501, a filter and rectifier circuit 502, and a power management unit 503. The current transformer 501 is used to generate an induced current based on the actual current on the cable under test, and output the induced current to the filter and rectifier circuit. The filter and rectifier circuit 502 is used to filter and rectify the induced current to obtain a power supply current. The power management unit 503 is used to use the power supply current to supply power to the voltage detection unit, the current detection unit, and the processing unit, respectively.

[0102] In one possible implementation, the current transformer 501 is a toroidal iron core wound with at least one turn of coil. The toroidal iron core has a closed or open structure, and the at least one turn of coil is used to connect to the rectifier and filter circuit. Figure 5D As shown, Figure 5D The diagram shows the equivalent structure of the power supply unit. The current transformer 501 is similar in principle to the commonly used current transformer, but the specific parameters are different, such as the number of turns of the coil wound around the toroidal iron core. The different number of turns leads to different induced currents. Therefore, different coil turns ratios can be set according to different power supply requirements. Those skilled in the art should know this, so it will not be elaborated here.

[0103] In one possible implementation, the power management unit is a direct current to direct current (DC / DC) DC / DC circuit. This DC / DC conversion circuit can be composed of devices such as switching transistors, diodes, inductors, and capacitors. The operating state of the DC / DC conversion circuit can be achieved by adjusting the operating states of these devices (e.g., the switching transistors). Specifically, the operating state of the DC / DC conversion circuit can be: converting received electrical energy into a suitable operating voltage for the voltage detection unit 11, the current detection unit 12, and the data processing unit 13. Specifically, the switching transistor in the DC / DC conversion circuit can be a metal-oxide-semiconductor (MOS) transistor, or a bipolar junction transistor (BJT), or any other device capable of switching functions; this application does not impose specific limitations on this.

[0104] In one possible implementation, the power management unit may further include a battery module. The DC / DC conversion circuit converts the received power and outputs it to the battery module. At this time, the DC / DC conversion circuit is in a charging state. When the voltage detection unit 11, the current detection unit 12, and the data processing unit 13 are in a working state, the power stored in the battery module is converted into a suitable voltage for the voltage detection unit 11, the current detection unit 12, and the data processing unit 13 for output. At this time, the DC / DC conversion circuit is in a discharging state.

[0105] Based on the AC power detection device provided in the above embodiments, the AC power detection device provided in this application can avoid the problem that the installation location of the AC power detection device is limited by the electrical connection point for AC voltage and current detection. Furthermore, since there is no electrical connection between the AC power detection device and the cable under test, while real-time detection of the amplitude and phase of the measured voltage and all harmonics of the cable under test, the safety level of the AC power detection device can be improved, and the cost of the AC power detection device can be reduced. Further, the AC power detection device provided in this application can also be powered without electrical connection, so that the AC power detection device is not limited by the location of the external power source and can work normally at any location of the cable under test. Moreover, based on the voltage detection unit in the AC power detection device of this application, and through the voltage detection calibration method provided in the embodiments of this application, the influence of changes in the position of the cable under test in the voltage sensor, cable thickness, and other external environmental conditions on the voltage detection accuracy can be solved, thereby obtaining more accurate voltage detection results, and thus more accurate power detection results.

[0106] Based on the same technical concept, this application also provides an AC voltage detection device, see reference. Figure 6 As shown, the AC voltage detection device 60 includes a voltage detection unit 61 and a data processing unit 62. The voltage detection unit 61 forms a coupling capacitor with the cable under test and is used to obtain a first voltage based on the actual voltage on the cable under test and the coupling capacitor, and output the first voltage to the data processing unit. The data processing unit 62 is used to receive the first voltage and determine the first voltage value; calculate the product of the first voltage value and the voltage amplification factor of the cable under test to determine the voltage value of the cable under test.

[0107] In one possible implementation, the voltage detection unit 61 includes: a voltage sensor, an amplifier circuit, and a phase-shift compensation circuit. The amplifier circuit includes a first input port, a second input port, and a first output port. The first input port is connected to the voltage sensor, the second input port is connected to ground, and the first output port is connected to the phase-shift compensation circuit.

[0108] The voltage sensor is a conductive cylindrical structure, and the cable under test passes through the voltage sensor, forming a coupling capacitance with the cable under test. The voltage sensor is used to generate an induced voltage based on the actual voltage on the cable under test and the coupling capacitance. The amplification circuit is used to amplify the induced voltage by a first factor and output a second voltage to the phase-shift compensation circuit through the output port. The phase-shift compensation circuit is used to phase-shift the second voltage and amplify it by a second factor, and output the first voltage.

[0109] In one possible implementation, the phase-shift compensation circuit is specifically used to lag the phase of the second voltage by 90°.

[0110] In one possible implementation, the voltage sensor is a closed or open cylindrical structure; the voltage sensor is made of a metallic material.

[0111] In one possible implementation, the voltage detection unit further includes: a single-pole double-throw switch and an RMS detection circuit;

[0112] The single-pole double-throw switch includes a second output port, a ground port, and a preset voltage input port; the single-pole double-throw switch is connected between the second input port and the ground wire, the second output port and the second input port are connected, the preset voltage input port is used to receive the input preset voltage, and the ground port is connected to the ground wire;

[0113] The amplifier circuit includes: a sub-amplifier circuit and a subtraction operation circuit;

[0114] The sub-amplifier circuit includes a third input port, a fourth input port, and a third output port; the subtraction circuit includes a fifth input port, a sixth input port, and a fourth output port; wherein the first input port and the third input port are connected, the second input port is connected to the fourth input port and the sixth input port respectively, the third output port and the fifth input port are connected, and the fourth output port and the first output port are connected; the first output port is also connected to the RMS detection circuit;

[0115] When the second output port is connected to the ground port, the sub-amplifier circuit amplifies the induced voltage by a first factor and outputs the second voltage to the phase-shift compensation circuit; when the second output port is connected to the preset voltage input port, the sub-amplifier circuit amplifies the difference between the induced voltage and the preset voltage by a first factor to obtain a third voltage, the subtraction circuit calculates the difference between the third voltage and the preset voltage to obtain a fourth voltage, and outputs the fourth voltage to the effective value detection circuit through the first output port;

[0116] The effective value detection circuit is used to receive the fourth voltage, extract the voltage component of the cable under test and the preset voltage component from the fourth voltage, determine the effective value of the voltage of the cable under test based on the voltage component of the cable under test and the preset voltage component, and send the effective value of the voltage of the cable under test to the data processing unit.

[0117] The data processing unit 62 is specifically used to: receive the effective value of the voltage of the cable under test; and determine the voltage amplification factor of the cable under test based on the ratio of the effective value of the first voltage to the effective value of the voltage of the cable under test.

[0118] The specific method by which the voltage detection unit 61 detects the voltage of the cable under test can be found in [reference needed]. Figure 4C The flowchart shown is not repeated here.

[0119] In one possible implementation, the device further includes a power supply unit 63; the power supply voltage is used to power the voltage detection unit and the data processing unit.

[0120] In one possible implementation, the power supply unit 63 includes: a current transformer, a filter and rectifier circuit, and a power management unit; the current transformer is used to generate an induced current based on the current on the cable under test, and output the induced current to the filter and rectifier circuit; the filter and rectifier circuit is used to filter and rectify the induced current to obtain a power supply current; the power management unit is used to use the power supply current to supply power to the voltage detection unit and the processing unit respectively.

[0121] In one possible implementation, the current transformer is a toroidal iron core wound with at least one turn of coil, the toroidal iron core being either closed or open, and the at least one turn of coil being used to connect to the rectifier and filter circuit; the power management unit is a DC-to-DC / DC converter circuit.

[0122] Furthermore, based on Figure 3A In addition to the structure of the voltage detection unit, this application also provides an AC power detection method, the method comprising: receiving a first voltage and a current of a cable under test, determining the first voltage value and the current value of the cable under test; calculating the product of the first voltage value and the voltage amplification factor of the cable under test, determining the voltage value of the cable under test; and calculating the electrical energy transmitted on the cable under test based on the voltage value of the cable under test and the current value of the cable under test.

[0123] In one possible implementation, the method further includes: receiving the effective value of the voltage of the cable under test; and determining the voltage amplification factor of the cable under test based on the ratio of the effective value of the first voltage to the effective value of the voltage of the cable under test.

[0124] In addition, this application provides an AC voltage detection method, the method comprising: receiving a first voltage and determining a first voltage value; calculating the product of the first voltage value and the voltage amplification factor of the cable under test, and determining the voltage value of the cable under test.

[0125] In one possible implementation, the method further includes: receiving the effective value of the voltage of the cable under test; and determining the voltage amplification factor of the cable under test based on the ratio of the effective value of the first voltage to the effective value of the voltage of the cable under test.

[0126] The above description is from the perspective of method embodiments. It is understood that, in order to implement the above methods, the AC power detection device may include hardware structures and / or software modules corresponding to the execution of various functions. Those skilled in the art should readily recognize that, based on the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0127] Based on the above embodiments, this application also provides a computer program that, when the computer program is run on a computer, causes the computer to execute the AC power detection method provided in the above embodiments, or causes the computer to execute the AC voltage detection method provided in the above embodiments.

[0128] Based on the above embodiments, this application also provides a computer-readable storage medium storing a computer program. When the computer program is executed by a computer, it causes the computer to perform the AC power detection method provided in the above embodiments, or causes the computer to perform the AC voltage detection method provided in the above embodiments.

[0129] The storage medium can be any available medium that a computer can access. For example, but not limited to, a computer-readable medium can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer.

[0130] Based on the above embodiments, this application also provides a chip, which is used to read a computer program stored in a memory to implement the AC power detection method or the AC voltage detection method provided in the above embodiments.

[0131] Based on the above embodiments, this application provides a chip system including a processor for supporting a computer device in implementing the AC power detection method or the AC voltage detection method provided in the above embodiments. In one possible design, the chip system further includes a memory for storing necessary programs and data of the computer device. This chip system may be composed of chips or may include chips and other discrete components.

[0132] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. A computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the flow or function according to the embodiments of this application is generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid-state disk (SSD)).

[0133] The various illustrative logic units and circuits described in the embodiments of this application can be implemented or operate the described functions using a general-purpose processor, digital signal processor, application-specific integrated circuit (ASIC), field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof. The general-purpose processor can be a microprocessor; alternatively, it can also be any conventional processor, controller, microcontroller, or state machine. The processor can also be implemented using a combination of computing devices, such as a digital signal processor and a microprocessor, multiple microprocessors, one or more microprocessors combined with a digital signal processor core, or any other similar configuration.

[0134] The steps of the methods or algorithms described in the embodiments of this application can be directly embedded in hardware, software units executed by a processor, or a combination of both. The software units can be stored in RAM, flash memory, ROM, EPROM, EEPROM, registers, hard disks, removable disks, CD-ROMs, or any other form of storage medium in the art. Exemplarily, the storage medium can be connected to the processor so that the processor can read information from and write information to the storage medium. Optionally, the storage medium can also be integrated into the processor. The processor and storage medium can be housed in an ASIC.

[0135] These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, such that the instructions, which execute on the computer or other programmable apparatus, provide steps for implementing the functions specified in one or more flowcharts and / or one or more block diagrams.

[0136] Although this application has been described in conjunction with specific features and embodiments, it is obvious that various modifications and combinations can be made thereto without departing from the spirit and scope of this application. Accordingly, this specification and drawings are merely illustrative descriptions of the application as defined by the appended claims, and are considered to cover any and all modifications, variations, combinations, or equivalents within the scope of this application. Clearly, those skilled in the art can make various alterations and modifications to this application without departing from its scope. Thus, if such modifications and modifications fall within the scope of the claims and their equivalents, this application is also intended to include such modifications and modifications.

Claims

1. An alternating current power detection device, characterized by, The device comprises a voltage detection unit, a current detection unit and a data processing unit; The voltage detection unit is coupled with the measured cable to form a coupling capacitor, and is used for calibrating the voltage detection unit after the relative position of the measured cable is fixed, the calibration process comprising: determining the effective value of the actual voltage of the measured cable after a preset voltage with a known voltage amplitude and a voltage frequency is amplified by an amplification circuit and a subtraction operation to remove the preset voltage component inconsistent with the actual voltage phase of the measured cable, the induced voltage being determined based on the actual voltage on the measured cable and the coupling capacitor; then amplifying the ground voltage and the induced voltage by the amplification circuit and phase-shifting and compensating by a phase-shifting compensation circuit to obtain a first voltage, determining the measured cable voltage amplification multiple according to the ratio between the effective value of the actual voltage of the measured cable and the effective value of the first voltage; after the calibration is completed, the first voltage is output to the data processing unit; The current detection unit is used for detecting the measured cable current and outputting the measured cable current to the data processing unit; The data processing unit is used for receiving the first voltage and the measured cable current, determining the first voltage value and the measured cable current value; calculating the product of the first voltage value and the measured cable voltage amplification multiple to determine the measured cable voltage value; and calculating the electric energy transmitted on the measured cable according to the measured cable voltage value and the measured cable current value.

2. The apparatus of claim 1, wherein, The voltage detection unit comprises a voltage sensor, an amplification circuit and a phase-shifting compensation circuit, and the amplification circuit comprises a first input port, a second input port and a first output port; wherein the first input port is connected with the voltage sensor, the second input port is connected with the ground wire, and the first output port is connected with the phase-shifting compensation circuit; The voltage sensor is a conductive cylindrical structure, the measured cable penetrates through the voltage sensor, and the voltage sensor forms a coupling capacitor with the measured cable; the voltage sensor is used for generating an induced voltage based on the actual voltage on the measured cable and the coupling capacitor; The amplification circuit is used for amplifying the induced voltage by a first multiple and outputting a second voltage to the phase-shifting compensation circuit through the output port; The phase-shifting compensation circuit is used for phase-shifting and amplifying the second voltage by a second multiple to output the first voltage.

3. The apparatus of claim 2, wherein, The phase-shifting compensation circuit is specifically used for lagging the phase of the second voltage by 90°.

4. The apparatus of claim 2 or 3, wherein, The voltage sensor is a closed or non-closed cylindrical structure; the voltage sensor is made of a metal material.

5. The apparatus of claim 2, wherein, The voltage detection unit further comprises a single-pole double-throw switch and an effective value detection circuit; The single-pole double-throw switch comprises a second output port, a grounding port and a preset voltage input port; the single-pole double-throw switch is connected across the second input port and the ground wire, the second output port is connected with the second input port, and the preset voltage input port is used for receiving an input preset voltage, and the grounding port is connected with the ground wire; The amplification circuit comprises a sub-amplification circuit and a subtraction operation circuit; The sub-amplification circuit comprises a third input port, a fourth input port and a third output port; the subtraction operation circuit comprises a fifth input port, a sixth input port and a fourth output port; wherein the first input port is connected with the third input port, the second input port is connected with the fourth input port and the sixth input port respectively, the third output port is connected with the fifth input port, and the fourth output port is connected with the first output port; the first output port is further connected with the effective value detection circuit; When the second output port is conducted with the ground port, the sub-amplification circuit is used for amplifying the induced voltage by a first multiple and outputting the second voltage to the phase shift compensation circuit; when the second output port is conducted with the preset voltage input port, the sub-amplification circuit is used for differentially amplifying the induced voltage and the preset voltage by a first multiple to obtain a third voltage, the subtraction operation circuit is used for calculating the difference between the third voltage and the preset voltage to obtain a fourth voltage, and the fourth voltage is output to the effective value detection circuit through the first output port; The effective value detection circuit is used for receiving the fourth voltage, extracting the measured cable voltage component and the preset voltage component in the fourth voltage respectively, determining the effective value of the measured cable voltage according to the measured cable voltage component and the preset voltage component, and sending the effective value of the measured cable voltage to the data processing unit; The data processing unit is specifically used for: receiving the effective value of the measured cable voltage; determining the amplification multiple of the measured cable voltage according to the ratio of the effective value of the first voltage to the effective value of the measured cable voltage.

6. The apparatus of claim 1, wherein, The device further comprises a power supply unit; the power supply unit is used for supplying power to the voltage detection unit and the data processing unit.

7. The apparatus of claim 6, wherein, The power supply unit comprises a power taking transformer, a filter rectifier circuit and an electric energy management unit; The power taking transformer is used for generating an induced current based on an actual current on the measured cable and outputting the induced current to the filter rectifier circuit; The filter rectifier circuit is used for filtering and rectifying the induced current to obtain a power supply current; The electric energy management unit is used for supplying power to the voltage detection unit, the current detection unit and the processing unit respectively by using the power supply current.

8. The apparatus of claim 7, wherein, The power taking transformer is a ring-shaped core with at least one winding coil, the ring-shaped core is a closed or non-closed structure, and the at least one winding coil is used for connecting to the rectifier filter circuit; the electric energy management unit is a direct current-direct current DC / DC circuit.

9. An alternating voltage detecting device, characterized by comprising: The device comprises a voltage detection unit and a data processing unit; The voltage detection unit is coupled with the measured cable to form a coupling capacitor, and is calibrated after the relative position of the measured cable is fixed, the calibration process comprising: removing a preset voltage component inconsistent with the actual voltage phase of the measured cable from a preset voltage with a known voltage amplitude and voltage frequency after the preset voltage is amplified and subtracted by an amplification circuit from an induced voltage, to determine the effective value of the actual voltage of the measured cable, the induced voltage being determined based on the actual voltage on the measured cable and the coupling capacitor; removing the preset voltage component inconsistent with the actual voltage phase of the measured cable from the induced voltage after the ground voltage is amplified and subtracted to obtain a first voltage, and determining the measured cable voltage amplification multiple according to the ratio between the effective value of the actual voltage of the measured cable and the effective value of the first voltage; after the calibration is completed, the first voltage is output to the data processing unit; The data processing unit is configured to receive the first voltage and determine a first voltage value; calculate the product of the first voltage value and the measured cable voltage amplification multiple to determine the measured cable voltage value.

10. The apparatus of claim 9, wherein, The voltage detection unit comprises a voltage sensor, an amplification circuit and a phase shift compensation circuit, the amplification circuit comprising a first input port, a second input port and a first output port; wherein the first input port is connected with the voltage sensor, the second input port is connected with the ground wire, and the first output port is connected with the phase shift compensation circuit; The voltage sensor is a conductive cylindrical structure, the measured cable penetrates through the voltage sensor, and the voltage sensor forms a coupling capacitor with the measured cable; the voltage sensor is configured to generate an induced voltage based on the actual voltage on the measured cable and the coupling capacitor; The amplification circuit is configured to amplify the induced voltage by a first multiple and output a second voltage to the phase shift compensation circuit through the output port; The phase shift compensation circuit is configured to phase shift and amplify the second voltage by a second multiple to output the first voltage.

11. The apparatus of claim 10, wherein, The phase shift compensation circuit is specifically configured to lag the phase of the second voltage by 90°.

12. The apparatus of claim 10 or 11, wherein, The voltage sensor is a closed or non-closed cylindrical structure; the voltage sensor is made of a metal material.

13. The apparatus of claim 10, wherein, The voltage detection unit further comprises a single-pole double-throw switch and an effective value detection circuit; The single-pole double-throw switch comprises a second output port, a ground port and a preset voltage input port; the single-pole double-throw switch is connected across the second input port and the ground wire, the second output port and the second input port are connected, and the preset voltage input port is configured to receive an input preset voltage, and the ground port is connected with the ground wire; The amplification circuit comprises a sub-amplification circuit and a subtraction operation circuit; The sub-amplification circuit includes a third input port, a fourth input port and a third output port; the subtraction operation circuit includes a fifth input port, a sixth input port and a fourth output port; wherein the first input port is connected with the third input port, the second input port is connected with the fourth input port and the sixth input port respectively, the third output port is connected with the fifth input port, and the fourth output port is connected with the first output port; the first output port is also connected with the effective value detection circuit; When the second output port is connected with the ground port, the sub-amplification circuit is used for amplifying the induced voltage by a first multiple, and outputting the second voltage to the phase shift compensation circuit; when the second output port is connected with the preset voltage input port, the sub-amplification circuit is used for differentially amplifying the induced voltage and the preset voltage by a first multiple to obtain a third voltage, the subtraction operation circuit is used for calculating the difference between the third voltage and the preset voltage to obtain a fourth voltage, and the fourth voltage is output to the effective value detection circuit through the first output port; The effective value detection circuit is used for receiving the fourth voltage, extracting the measured cable voltage component and the preset voltage component in the fourth voltage respectively, and determining the effective value of the measured cable voltage according to the measured cable voltage component and the preset voltage component, and sending the effective value of the measured cable voltage to the data processing unit; The data processing unit is specifically used for: receiving the effective value of the measured cable voltage; determining the amplification multiple of the measured cable voltage according to the ratio of the effective value of the first voltage to the effective value of the measured cable voltage.

14. The apparatus of claim 9, wherein, The device further includes a power supply unit; the power supply unit is used for supplying power to the voltage detection unit and the data processing unit.

15. The apparatus of claim 14, wherein, The power supply unit includes a power taking transformer, a filter rectifier circuit and an electric energy management unit; The power taking transformer is used for generating an induced current based on the current on the measured cable, and outputting the induced current to the filter rectifier circuit; The filter rectifier circuit is used for filtering and rectifying the induced current to obtain a power supply current; The electric energy management unit is used for supplying power to the voltage detection unit and the processing unit respectively by using the power supply current.

16. The apparatus of claim 15, wherein, The power taking transformer is a ring-shaped core with at least one winding coil, the ring-shaped core is a closed or non-closed structure, and the at least one winding coil is used for connecting to the rectification and filtering circuit; the electric energy management unit is a direct current-direct current DC / DC circuit.

17. An alternating current power detection method, characterized by, The method includes: A coupling capacitor is formed with the measured cable, and calibration is performed after the position of the measured cable is fixed. The calibration process includes: determining the effective value of the actual voltage of the measured cable after a preset voltage with a known voltage amplitude and voltage frequency is amplified by an amplification circuit, a subtraction operation is performed, and a preset voltage component inconsistent with the phase of the actual voltage of the measured cable is removed, the induced voltage being determined based on the actual voltage on the measured cable and the coupling capacitor; the ground voltage and the induced voltage are amplified by the amplification circuit and are phase-shifted and compensated by a phase-shift compensation circuit to obtain a first voltage, and the voltage amplification multiple of the measured cable is determined according to the ratio between the effective value of the actual voltage of the measured cable and the effective value of the first voltage; After the calibration is completed, the first voltage and the measured cable current are received, and the first voltage value and the measured cable current value are determined; The product of the first voltage value and the voltage amplification multiple of the measured cable is calculated to determine the measured cable voltage value; The electric energy transmitted on the measured cable is calculated according to the measured cable voltage value and the measured cable current value.

18. The method of claim 17, wherein, The method further includes: The effective value of the measured cable voltage is received; The voltage amplification multiple of the measured cable is determined according to the ratio between the effective value of the first voltage and the effective value of the measured cable voltage.

19. An alternating voltage detection method, characterized by, The method includes: A coupling capacitor is formed with the measured cable, and calibration is performed after the position of the measured cable is fixed. The calibration process includes: determining the effective value of the actual voltage of the measured cable after a preset voltage with a known voltage amplitude and voltage frequency is amplified by an amplification circuit, a subtraction operation is performed, and a preset voltage component inconsistent with the phase of the actual voltage of the measured cable is removed, the induced voltage being determined based on the actual voltage on the measured cable and the coupling capacitor; the ground voltage and the induced voltage are amplified by the amplification circuit and are phase-shifted and compensated by a phase-shift compensation circuit to obtain a first voltage, and the voltage amplification multiple of the measured cable is determined according to the ratio between the effective value of the actual voltage of the measured cable and the effective value of the first voltage; After the calibration is completed, the first voltage is received, and the first voltage value is determined; The product of the first voltage value and the voltage amplification multiple of the measured cable is calculated to determine the measured cable voltage value.

20. The method of claim 19, wherein, The method further includes: The effective value of the measured cable voltage is received; The voltage amplification multiple of the measured cable is determined according to the ratio between the effective value of the first voltage and the effective value of the measured cable voltage.

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