Phase difference detection device and detection method

Abstract

The present invention is applicable to the field of electric power testing technology, and provides a phase difference detection device and a detection method, wherein the phase difference detection device comprises: a hardware zero-crossing module, which converts the alternating voltage to be measured into a positive-zero alternating voltage; a signal processing module, which is connected to the hardware zero-crossing module and is used to convert the voltage into a signal type voltage used by the hardware zero-crossing module; a transition edge monitoring module, which is used to monitor the transition edge of the square wave from the high level to the low level and send out a signal notification; a high-low level monitoring module, which is connected to the transition edge monitoring module and is used to perform timing judgment and storage of the high and low levels of the incoming signal; a filtering module, which is connected to the high-low level monitoring module and realizes filtering of the level jump caused by signal noise; and a phase difference monitoring module, which processes and summarizes the received data through calculation and logic execution programs to obtain phase difference data. The present invention has the advantages of accurate inspection data, good security, and overcoming detection limitations.

Description

Technical Field

[0001] The present invention belongs to the technical field of electric power testing, and in particular relates to a phase difference detection device and a detection method. Background Art

[0002] Phase difference is an extremely important electrical quantity in high and low voltage complete sets of equipment. It is usually used to switch the incoming line when the rotating load stops, to capture the bus voltage of the rotating load and the incoming line voltage to be switched, and to monitor whether there is asymmetry in the three-phase power load when the system is running, which may cause harm to the power equipment. Domestic phase difference measurement lags behind the world's advanced level. High-precision phase detection is particularly important with the development of power systems and the progress of national defense, medical care and high-tech industries. At present, phase detection equipment has problems such as long phase detection time, harsh phase detection conditions, and easy signal noise affecting accuracy. Summary of the invention

[0003] The purpose of the embodiment of the present invention is to provide a phase difference detection device, aiming to solve the problem that the accuracy of the received signal is easily affected by clutter.

[0004] The embodiment of the present invention is implemented as follows: a phase difference detection device, the phase difference detection device comprising:

[0005] The hardware zero-crossing module converts the alternating voltage to be measured into a positive-zero alternating voltage;

[0006] The signal processing module is connected to the hardware zero-crossing module and is used to convert the voltage into a signal type voltage used by the hardware zero-crossing module;

[0007] The transition edge monitoring module is used to monitor the transition edge of the square wave from high level to low level and send out a signal notification;

[0008] The high and low level monitoring module is connected to the transition edge monitoring module and is used to make timing judgments and store the high and low levels of the incoming signal;

[0009] The filtering module is connected to the high and low level monitoring module to filter out the level jump caused by signal noise;

[0010] The phase difference monitoring module processes and summarizes the received data through calculation and logic execution programs to obtain phase difference data;

[0011] A communication module, used for transmitting the phase difference data to the outside;

[0012] Power module, used to provide operating energy.

[0013] Another object of an embodiment of the present invention is to provide a phase difference detection method, which is applied to the phase difference detection device described above. The phase difference detection method includes:

[0014] The signal processing module receives the voltage, reduces and filters it, and performs signal conversion;

[0015] The hardware zero-crossing module converts the sine wave signal into a rectangular wave;

[0016] The high and low level monitoring module samples and judges the high and low levels of the signal, and continuously stores multiple historical data into a one-dimensional data matrix, and transmits the one-dimensional data matrix to the filtering module for use;

[0017] The jump edge monitoring module receives the signal and determines the trigger interrupt, sends a trigger signal to the filter module, and the filter module filters the data and transmits the judgment result to the phase difference monitoring module. The multi-channel electrical data is connected to the signal processing module, and the voltage transformer in the signal processing module performs signal transformation. The transformation ratio is required to be 100V for the normal operating voltage (such as 10KV). Voltage transformation ratio coefficient = normal operating voltage / 100; the signal after transformation is connected to the signal processing module for voltage reduction and filtering. The collected voltage and current are combined and sorted into 0-3.3V signals that can be used by the data conversion module through analog circuit combination. And the signal is sent to the hardware zero-crossing module. The hardware zero-crossing module compares the data transmitted by the signal processing module with 1.65V through hardware, and converts the 0-3.3V sine wave signal into a rectangular wave of the same frequency through this module. The high level of the rectangle is 3.3V and the low level is 0V. And the converted signal is transmitted to the high and low level monitoring module and the jump edge monitoring module. After the high and low level monitoring module receives the signal from the hardware zero-crossing module, the timer performs high and low level sampling and judgment on the signal at 1ms intervals, and continuously stores multiple historical data into a one-dimensional data matrix, and transmits the one-dimensional data matrix to the filter module for use. After the jump edge monitoring module receives the signal from the hardware zero-crossing module, if it detects that the interrupt is triggered by the jump edge, it sends a trigger signal to the filter module, and the filter module filters the data. The filter module receives the one-dimensional data matrix transmitted from the high and low level module, and performs a majority filter on the matrix, that is, checks all the data in the one-dimensional data matrix one by one. If it is a high level, the majority high level count value is increased by one, and if it is a low level, the majority low level count value is increased by one. After all judgments are completed, the majority high level count value and the majority low level count value are compared, and the larger value is taken as the majority filtering result. After receiving the transition edge interrupt signal transmitted from the transition edge monitoring module, the filter module judges the direction of the transition edge in combination with the majority value of the high and low level modules, that is, if the majority value is high, the transition edge is a transition from high level to low level, and vice versa if the majority value is low, the transition edge is a transition from low level to high level. And transmit the judgment result to the phase difference monitoring module. After receiving the transition edge signal and transition edge direction sent by the filter module, the phase difference monitoring module records the value of the current timer. If it is a transition from low level to high level, the value is used as the high level transition phase data of the data of this channel. If it is a transition from high level to low level, it will be changed into the low level transition phase data of the data of this channel. And use this phase data to make a difference with the corresponding channels of other channels, channel 1 low level transition phase data - channel 2 low level transition phase data = phase difference between channel 2 and channel 1. Similarly, channel 1 high level transition phase data - channel 2 high level transition phase data = phase difference between channel 2 and channel 1.The filtering module is used to filter the data, which ensures that the collected data is accurate and not affected by clutter. The phase difference monitoring solution can realize real-time warning of large phase difference and minimize the possibility of dual power switching accidents caused by excessive phase difference. It can solve the limitation that the current phase difference calculation equipment requires a certain frequency or that the two channels must have the same frequency. The advantages of the present invention are: accurate inspection data, good safety, and overcoming detection limitations. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A structural block diagram of a phase difference detection device provided by an embodiment of the present invention;

[0019] Figure 2 A flow chart of a phase difference detection device provided by an embodiment of the present invention; DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0021] The specific implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0022] like Figure 1 As shown, it is a block diagram of a phase difference detection device provided by an embodiment of the present invention, comprising:

[0023] The hardware zero-crossing module converts the alternating voltage to be measured into a positive-zero alternating voltage;

[0024] The signal processing module is connected to the hardware zero-crossing module and is used to convert the voltage into a signal type voltage used by the hardware zero-crossing module;

[0025] The transition edge monitoring module is used to monitor the transition edge of the square wave from high level to low level and send out a signal notification;

[0026] The high and low level monitoring module is connected to the transition edge monitoring module and is used to make timing judgments and store the high and low levels of the incoming signal;

[0027] The filtering module is connected to the high and low level monitoring module to filter out the level jump caused by signal noise;

[0028] The phase difference monitoring module processes and summarizes the received data through calculation and logic execution programs to obtain phase difference data;

[0029] A communication module, used for transmitting the phase difference data to the outside;

[0030] Power module, used to provide operating energy.

[0031] In an embodiment of the present invention, multiple channels of electrical data are connected to the signal processing module, and the voltage transformer in the signal processing module performs signal transformation, and the transformation ratio requirement is that the voltage (such as 10KV) of normal operation is 100V. Voltage transformation ratio coefficient = normal operating voltage / 100; the signal after transformation is connected to the signal processing module for voltage reduction and filtering. The collected voltage and current are combined and sorted into a 0-3.3V signal that can be used by the data conversion module through an analog circuit. And the signal is sent to the hardware zero-crossing module. The hardware zero-crossing module compares the data transmitted by the signal processing module with 1.65V through hardware, and converts the 0-3.3V sinusoidal wave signal into a rectangular wave of the same frequency through this module, and the high level of the rectangle is 3.3V and the low level is 0V. And the converted signal is transmitted to the high and low level monitoring module and the jump edge monitoring module. After the high and low level monitoring module receives the signal from the hardware zero-crossing module, the timer performs high and low level sampling and judgment on the signal at 1ms intervals, and continuously stores multiple historical data into a one-dimensional data matrix, and transmits the one-dimensional data matrix to the filter module for use. After the jump edge monitoring module receives the signal from the hardware zero-crossing module, if it detects that the interrupt is triggered by the jump edge, it sends a trigger signal to the filter module, and the filter module filters the data. The filter module receives the one-dimensional data matrix transmitted from the high and low level module, and performs a majority filter on the matrix, that is, checks all the data in the one-dimensional data matrix one by one. If it is a high level, the majority high level count value is increased by one, and if it is a low level, the majority low level count value is increased by one. After all judgments are completed, the majority high level count value and the majority low level count value are compared, and the larger value is taken as the majority filtering result. After receiving the transition edge interrupt signal transmitted from the transition edge monitoring module, the filter module judges the direction of the transition edge in combination with the majority value of the high and low level modules, that is, if the majority value is high, the transition edge is a transition from high level to low level, and vice versa if the majority value is low, the transition edge is a transition from low level to high level. And transmit the judgment result to the phase difference monitoring module. After receiving the transition edge signal and transition edge direction sent by the filter module, the phase difference monitoring module records the value of the current timer. If it is a transition from low level to high level, the value is used as the high level transition phase data of the data of this channel. If it is a transition from high level to low level, it will be changed into the low level transition phase data of the data of this channel. And use this phase data to make a difference with the corresponding channels of other channels, channel 1 low level transition phase data - channel 2 low level transition phase data = phase difference between channel 2 and channel 1. Similarly, channel 1 high level transition phase data - channel 2 high level transition phase data = phase difference between channel 2 and channel 1. The phase difference monitoring solution, which ensures accurate data collection and is not affected by noise, can filter through the filter module, realize real-time warning of large phase difference, minimize the possibility of dual power switching accidents caused by excessive phase difference, and solve the limitation of current phase difference calculation equipment that the frequency requirement is certain or the two channels must be at the same frequency.

[0032] As a preferred embodiment of the present invention, the signal processing module includes a voltage transformer and a rectifier module. The voltage transformer is used to scale the high voltage signal to the required signal amplitude range in the same proportion, and the rectifier module is used to move the entire signal reference point so that it does not exceed the range of the signal type that the hardware zero-crossing module can use. The signal after the ratio is connected to the rectifier module for voltage reduction and filtering. The collected voltage and current are combined and organized into a signal that can be used by the data conversion module through an analog circuit. And the signal is sent to the hardware zero-crossing module.

[0033] As a preferred embodiment of the present invention, the hardware zero-crossing module includes an AD sampler and a voltage comparator, wherein the AD sampler is used to collect square wave voltage, and the voltage comparator is used to compare the voltage signal to be measured with the reference voltage to realize the rectification function. The AD sampler performs discrete sampling on the converted square wave and transmits the discrete sampling signal to the next required module.

[0034] As a preferred embodiment of the present invention, the transition edge monitoring module includes a central processing unit and an external interrupt module. The central processing unit is used to process signals and save transition edge signals; the external interrupt module is used to transmit transition edge trigger signals to the filtering module.

[0035] As a preferred embodiment of the present invention, the high and low level monitoring module includes a GPIO general input and output module, a central processing unit and a timer module. The GPIO general input and output module is used to read the level of the monitored signal, the central processing unit is used to process and store the monitored level, and the timer module realizes regular level judgment of the monitored signal.

[0036] As a preferred embodiment of the present invention, the communication module includes an RS485 communication module and a universal output module. The RS485 communication module is used to implement protocol transmission, and the universal output module is an output point for receiving abnormal signals from outside the system.

[0037] As a preferred embodiment of the present invention, the phase difference detection device further includes an additional module for realizing other functional modules besides the core functions of the device. The additional module includes a human-computer interaction module and an acoustic and visual alarm module. The human-computer interaction module is used for users to debug and set relevant values. The acoustic and visual alarm module is used to display the normal operation of the entire system. If there is a problem with the system operation status, it will give an acoustic and visual prompt to the outside of the system.

[0038] As another preferred embodiment of the present invention, the power module adopts a switching power supply solution to power the entire system, and the application scenario is a normal operating condition: 380V; therefore, the parameter of the voltage transformer in the signal processing module is 380:100. The hardware zero-crossing module adopts an analog circuit mainly composed of an LM2091 voltage comparator and a 12-bit AD sampler with an STM32F49IGT6 single-chip microcomputer. The GPIO module, central processing unit, timer module and external interrupt module in the high and low level monitoring module and the transition edge monitoring module are all integrated with the STM32F429IGT6 single-chip microcomputer. In this example, we use RS485 communication and display screen as human-computer interaction modules. Buzzer and LED light modules are used as sound and light alarm modules. The connection mode of the system is that the input of the signal processing module is connected to the measurement to be measured, the ADC sampling module of the STM32F429IGT6 is connected to the output of the signal processing module, and the output of the ADC sampling module of the STM32F429IGT6 is connected to the central processing unit (COTEX-M core). The central processor sends the serial port modulation information to the display screen module through RS485 communication for human-computer interaction. The general input and output module of STM32F429IGT6 is connected with the buzzer module and the LED module.

[0039] After connecting the multi-channel voltages to be monitored for phase difference to the corresponding terminals, the entire system is powered by AC 220V, and the human-computer interaction device is used to set the phase difference data between the two terminals to be measured, the universal input module timing of the high and low level monitoring module is 1ms, and the phase difference alarm threshold is 20 degrees. The entire preparation work is completed.

[0040] Under normal operation, the voltage to be measured is first transformed and adjusted accordingly by the signal processing module. In this example, the 390V sinusoidal voltage is transformed into a 100V sinusoidal voltage signal after passing through the voltage transformer, and is adjusted to a sinusoidal signal with an amplitude of 1.5V and a zero point reference of 1.65V by the analog circuit. The processed signal is sent to the hardware zero-crossing module, and the signal is sampled by the ADC. The sampled value is a sinusoidal signal. The voltage is compared with 1.65V by the voltage comparator in the hardware zero-crossing module. If the value of the signal is greater than 1.65V, the hardware zero-crossing module outputs 3.3V. If the value of the signal is less than 1.65V, the hardware zero-crossing module outputs 0V. The hardware zero-crossing module converts the sinusoidal signal into a rectangular wave signal, and transmits the rectangular wave signal to the high and low level monitoring module and the jump edge monitoring module. After receiving the matrix wave signal, the high and low level monitoring module samples the rectangular wave according to the 1ms time set by the human-computer interaction device, and determines whether it belongs to TTL high level or TTL low level (high level>2.4V, low level<0.4V) and records the determined value in real time in a one-dimensional data matrix with a data length of 5. The data matrix gradually expands over time until it expands to 5, then the count value is cleared to 0 and continues to be stored from the head of the one-dimensional matrix. After receiving the matrix signal, the jump edge monitoring module sets the external interrupt module as edge trigger through the external interrupt module, and when there is a high and low level jump, an interrupt signal will be sent to the central processing unit. The interrupt system of the central processing unit forces the CPU to suspend the task being executed and enter the interrupt program for processing; after the interrupt is processed, it continues to execute at the return to the interrupted program. After the filter module receives the interrupt signal sent by the transition edge monitoring module, it jumps to the interrupt module part. First, it detects whether the mode of the voltage signal of the channel is high or low in the one-dimensional data matrix stored by the high and low level monitoring module. If it is high, it can be judged that the transition edge at this time is a transition from high level to low level; if it is low, it can be judged that the transition edge at this time is a transition from low level to high level, and the information is sent to the phase difference monitoring module. After receiving the transition information, the phase difference monitoring module saves the real-time running value of the timer in the phase data buffer of the channel. If the transition information is a high level jump to a low level, it is saved in the high level jump to low level phase data buffer of the channel. If the transition information is a low level jump to a high level, it is saved in the low level jump to high level phase data buffer of the channel. If the channel is a channel that needs to calculate the phase difference, the phase data buffer of the channel is subtracted from the corresponding transition phase data buffer of the reference channel (that is, the other channel for the phase difference). That is, the high level jump to low level phase data buffer of the channel to be calculated is subtracted from the high level jump to low level phase data buffer of the reference channel. The low level jump to high level fragrance data buffer of the channel to be calculated is subtracted from the low level jump to high level phase data buffer of the reference channel.The interpolation is the time difference when the two channels pass through zero. The phase difference value can be obtained by performing a mathematical identity transformation on the time difference. The size of the phase difference and the phase difference alarm threshold set by the human-computer interaction module are judged. If the phase difference is greater than the phase difference alarm threshold, the buzzer module and the LED light module are triggered to indicate that the phase difference is abnormal, and the phase difference value is transmitted to the human-computer interaction module through the communication module for display.

[0041] An embodiment of the present invention also provides a phase difference detection method, which is applied to the phase difference detection device described above. The phase difference detection method includes:

[0042] The signal processing module receives the voltage, reduces and filters it, and performs signal conversion;

[0043] The hardware zero-crossing module converts the sine wave signal into a rectangular wave;

[0044] The high and low level monitoring module samples and judges the high and low levels of the signal, and continuously stores multiple historical data into a one-dimensional data matrix, and transmits the one-dimensional data matrix to the filtering module for use;

[0045] The transition edge monitoring module receives the signal and determines the trigger interrupt, sends a trigger signal to the filtering module, and the filtering module filters the data and transmits the judgment result to the phase difference monitoring module.

[0046] Step 1: Connect multiple channels of electrical data to the signal processing module, and the voltage transformer in the signal processing module performs signal transformation. The transformation ratio is required to be 100V for the normal operating voltage (such as 10KV). Voltage transformation ratio coefficient = normal operating voltage / 100; the transformed signal is connected to the rectifier module for voltage reduction and filtering. The collected voltage and current are combined and sorted into 0-3.3V signals that can be used by the data conversion module through analog circuit combination. And the signal is sent to the hardware zero-crossing module.

[0047] Step 2: The hardware zero-crossing module compares the data transmitted by the signal processing module with 1.65V through hardware. The specific comparison process is to use a voltage comparator to compare the size of the two voltages. When the positive input voltage is higher than the negative input voltage, the voltage comparator outputs a high level. When the positive input voltage is lower than the negative input voltage, the voltage comparator outputs a low level. Through this module, the 0-3.3V sine wave signal is converted into a rectangular wave of the same frequency. The high level of the rectangle is 3.3V and the low level is 0V. The converted signal is transmitted to the high and low level monitoring module and the transition edge monitoring module.

[0048] Step 3: After the high and low level monitoring module receives the signal from the hardware zero-crossing module, the timer samples the signal at 1ms intervals, continuously stores multiple historical data into a one-dimensional data matrix, and transmits the one-dimensional data matrix to the filter module for use. After the transition edge monitoring module receives the signal from the hardware zero-crossing module, the external interrupt module detects whether an interrupt is triggered. If it is detected that the interrupt is triggered by the transition edge, a trigger signal is sent to the filter module, and the filter module filters the data.

[0049] Step 4: The filter module receives the one-dimensional data matrix transmitted from the high and low level module, and performs majority filtering on the matrix, that is, checks all the data in the one-dimensional data matrix one by one. If it is a high level, the majority high level count value is increased by one, and if it is a low level, the majority low level count value is increased by one. After all the judgments are completed, the majority high level count value and the majority low level count value are compared, and the larger value is taken as the majority filtering result. After the filter module receives the transition edge interrupt signal transmitted from the transition edge monitoring module, it combines the majority value of the high and low level modules to determine the direction of the transition edge, that is, if the majority value is a high level, the transition edge is a high level to low level jump, otherwise if the majority value is a low level, the transition edge is a low level to high level jump. And transmit the judgment result to the phase difference monitoring module.

[0050] Step 5: After receiving the transition edge signal and transition edge direction sent by the filtering module, the phase difference monitoring module records the value of the current timer. If it is a transition from low level to high level, the value is used as the high level transition phase data of the data. If it is a transition from high level to low level, it will be changed into the low level transition phase data of the data. And use this phase data to make a difference with the corresponding channels of other channels, channel 1 low level transition phase data - channel 2 low level transition phase data = phase difference between channel 2 and channel 1. Similarly, channel 1 high level transition phase data - channel 2 high level transition phase data = phase difference between channel 2 and channel 1.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A phase difference detection device, characterized in that: The phase difference detection device comprises: The hardware zero-crossing module converts the alternating voltage to be measured into a positive-zero alternating square wave voltage; A signal processing module, connected to the hardware zero-crossing module, for converting the voltage into a signal type voltage used by the hardware zero-crossing module; A transition edge monitoring module is used to monitor the transition edge of the square wave between the high level and the low level and send out a signal notification. The transition edge monitoring module includes a central processing unit and an external interrupt module. The central processing unit is used to process the signal and save the transition edge signal; the external interrupt module is used to transmit the transition edge trigger signal to the filtering module; A high and low level monitoring module is connected to the transition edge monitoring module and is used to perform timing judgment and storage on the high and low levels of the incoming signal. The high and low level monitoring module includes a GPIO general input and output module, a central processing unit and a timer module. The GPIO general input and output module is used to read the level of the monitored signal, the central processing unit is used to process and store the monitored level, and the timer module realizes timing level judgment on the monitored signal; The filtering module is connected to the high and low level monitoring module to filter out the level jump caused by signal noise; The signal converted by the hardware zero-crossing module is output to the high-low level monitoring module and the transition edge monitoring module. After the high-low level monitoring module receives the signal from the hardware zero-crossing module, the timer performs high-low level sampling and judgment on the signal at fixed intervals, and continuously stores multiple historical data into a one-dimensional data matrix, and transmits the one-dimensional data matrix to the filtering module for use. After the transition edge monitoring module receives the signal from the hardware zero-crossing module, if it detects that the interrupt is triggered by the transition edge, it sends a trigger signal to the filtering module, and the filtering module filters the data; The filtering module receives the one-dimensional data matrix transmitted from the high and low level modules, and performs majority filtering on the matrix. If it is a high level, the majority high level count value is increased by one, and if it is a low level, the majority low level count value is increased by one. After all judgments are completed, the majority high level count value and the majority low level count value are compared, and the larger value is taken as the majority filtering result. After the filtering module receives the transition edge interrupt signal transmitted from the transition edge monitoring module, it combines the majority value of the high and low level modules to determine the direction of the transition edge. If the majority value is a high level, the transition edge is a transition from a high level to a low level. Conversely, if the majority value is a low level, the transition edge is a transition from a low level to a high level. The phase difference monitoring module processes and summarizes the received data through calculation and logic execution programs to obtain phase difference data; Power module, used to provide operating energy.

2. A phase difference detection device according to claim 1, characterized in that: The signal processing module includes a voltage transformer and a rectifier module. The voltage transformer is used to scale the high voltage signal to the required signal amplitude range in the same proportion, and the rectifier module is used to move the entire signal reference point so that it does not exceed the range of the signal type that can be used by the hardware zero-crossing module.

3. A phase difference detection device according to claim 1, characterized in that: The hardware zero-crossing module includes an AD sampler and a voltage comparator. The AD sampler is used to collect square wave voltage, and the voltage comparator is used to compare the voltage signal to be measured with the reference voltage to realize the rectification function.

4. A phase difference detection device according to claim 1, characterized in that: The phase difference detection device also includes a communication module, which includes an RS485 communication module and a universal output module. The RS485 communication module is used to implement protocol transmission, and the universal output module is an output point for receiving abnormal signals from the system outside the system.

5. The phase difference detection device according to claim 1, characterized in that: The phase difference detection device also includes an additional module.

6. A phase difference detection device according to claim 5, characterized in that: The additional module includes a human-computer interaction module and an audible and visual alarm module. The human-computer interaction module is used for users to debug and set relevant values, and the audible and visual alarm module is used to display the normal operation of the entire system.

7. A phase difference detection method, applied to a phase difference detection device according to any one of claims 1 to 6, characterized in that: The phase difference detection method comprises: The signal processing module receives the voltage, reduces and filters it, and performs signal conversion; The hardware zero-crossing module converts the sine wave signal into a rectangular wave; The high and low level monitoring module samples and judges the high and low levels of the signal, and continuously stores multiple historical data into a one-dimensional data matrix, and transmits the one-dimensional data matrix to the filtering module for use; The transition edge monitoring module receives the signal and determines the trigger interrupt, sends a trigger signal to the filtering module, and the filtering module filters the data and transmits it to the phase difference monitoring module; The phase difference monitoring module checks and judges the data and outputs the data difference.

8. A phase difference detection method according to claim 7, characterized in that: The data difference is a data difference value of channels with the same level.

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