CN213275762U - Phase difference detection device - Google Patents
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- CN213275762U CN213275762U CN202022258652.9U CN202022258652U CN213275762U CN 213275762 U CN213275762 U CN 213275762U CN 202022258652 U CN202022258652 U CN 202022258652U CN 213275762 U CN213275762 U CN 213275762U
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Abstract
The utility model is suitable for an electric power test technical field provides a phase difference detection device, phase difference detection device includes: the hardware zero-crossing module is used for converting the alternating voltage to be measured into positive zero alternating voltage; the signal processing module is connected with the hardware zero-crossing module and is used for converting the voltage into a signal type voltage used by the hardware zero-crossing module; the jumping edge monitoring module is used for monitoring the jumping edge of the square wave between a high level and a low level and sending out a signal notice; the high and low level monitoring module is connected with the jumping edge monitoring module and is used for carrying out timing judgment and storage on the high and low levels of the transmitted signals; the filtering module is connected with the high and low level monitoring module and is used for filtering level jump caused by signal noise; and the phase difference monitoring module processes and summarizes the received data through calculation and logic execution programs to obtain phase difference data. The utility model discloses the advantage: the inspection data is accurate, the safety is good, and the detection limitation is overcome.
Description
Technical Field
The utility model belongs to the technical field of the electric power test, especially, relate to a phase difference detection device.
Background
The phase difference is an important electrical quantity in high-voltage and low-voltage complete equipment, and is generally used for a synchronous capturing function of incoming line switching for bus voltage of a rotating load and incoming line voltage to be switched when the rotating load is shut down, and whether three-phase electrical load asymmetry causes damage to electrical equipment when a monitoring system runs. The domestic phase difference measurement aspect falls behind the world advanced level, and the high-precision phase discrimination is particularly important along with the development of power systems and the progress of national defense medical treatment and high and new technology industries. The prior phase discrimination equipment has the problems of long phase discrimination time, harsh phase discrimination condition, easy signal clutter reception influence on precision and the like.
SUMMERY OF THE UTILITY MODEL
An object of the embodiment of the utility model is to provide a phase difference detection device, aim at solving the problem that the easy signal clutter of receiving influences the precision.
The embodiment of the utility model provides a realize like this, a phase difference detection device, phase difference detection device includes:
the hardware zero-crossing module is used for converting the alternating voltage to be measured into positive zero alternating voltage;
the signal processing module is connected with the hardware zero-crossing module and is used for converting the voltage into a signal type voltage used by the hardware zero-crossing module;
the jumping edge monitoring module is used for monitoring the jumping edge of the square wave between a high level and a low level and sending out a signal notice;
the high and low level monitoring module is connected with the jumping edge monitoring module and is used for carrying out timing judgment and storage on the high and low levels of the transmitted signals;
the filtering module is connected with the high and low level monitoring module and is used for filtering level jump caused by signal noise;
the phase difference monitoring module processes and summarizes the received data through calculation and logic execution programs to obtain phase difference data;
the communication module is used for transmitting the phase difference data to the outside;
and the power supply module is used for providing operation energy.
Another object of the present invention is to provide a phase difference detecting method, which is applied to the above phase difference detecting apparatus, the phase difference detecting method comprising:
the signal processing module receives the voltage to reduce and filter, 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 carries out high and low level sampling judgment on the signal, continuously stores a plurality of historical data, puts the historical data into a one-dimensional data matrix, and transmits the one-dimensional data matrix to the filtering module for use;
the jumping edge monitoring module receives the signal and judges triggering interruption, sends a triggering signal to the filtering module, and the filtering module filters data and transmits a judgment result to the phase difference monitoring module. And (3) connecting the multi-path electrical data into the signal processing module, and performing signal transformation ratio by a voltage transformer in the signal processing module, wherein the transformation ratio is required to be 100V for the voltage (such as 10 KV) of normal operation. Voltage transformation ratio coefficient = normal operating voltage/100; and the signal after the transformation ratio is accessed into a signal processing module to reduce and filter the voltage. Collected voltage and current are combined and arranged into signals of 0-3.3V which can be used by the data conversion module through the analog circuit. And sends the signal to a hardware zero crossing module. The hardware zero-crossing module compares data transmitted by the signal processing module with 1.65V through hardware, and the module converts a sine wave signal of 0-3.3V into a rectangular wave with the same frequency, wherein the high level of the rectangular wave is 3.3V, and the low level of the rectangular wave is 0V. And transmitting the converted signal into a high-low level monitoring module and a jumping edge monitoring module. After receiving the signal from the hardware zero-crossing module, the high-low level monitoring module performs high-low level sampling judgment on the signal at the interval of 1ms by the timer, continuously stores a plurality of historical data, puts the historical data into a one-dimensional data matrix, and transmits the one-dimensional data matrix to the filtering module for use. After receiving the signal from the hardware zero crossing module, the jump edge monitoring module sends a trigger signal to the filtering module if detecting that the interruption is triggered by the jump edge, and the filtering module filters the data. The filtering module receives the one-dimensional data matrix transmitted by the high-low level module, carries out mode filtering on the matrix, namely, checks all data in the one-dimensional data matrix one by one, if the data is high level, the mode high level counting value is added with one, if the data is low level, the mode low level counting value is added with one, compares the mode high level counting value with the mode low level counting value after all judgment is finished, and takes a larger value as a mode filtering result. After receiving the jump edge interrupt signal transmitted by the jump edge monitoring module, the filtering module judges the direction of the jump edge by combining the mode value of the high-low level module, namely if the mode value is high level, the jump edge jumps from high level to low level, otherwise, if the mode value is low level, the jump edge jumps from low level to high level. And transmitting the judgment result to the phase difference monitoring module. And the phase difference monitoring module records the value of the current timer after receiving the jump edge signal and the jump edge direction sent by the filtering module, and if the jump edge signal and the jump edge direction jump from the low level to the high level, the value is used as the high level jump phase data of the data. If the high level jumps to the low level, the low level jump phase data of the path of data is reformed. And performing subtraction with the phase data and corresponding channels of other channels, wherein channel 1 low level jump phase data-channel 2 low level jump phase data = phase difference between channel 2 and channel 1. Similarly, channel 1 high level jump phase data-channel 2 high level jump phase data = phase difference between channel 2 and channel 1. The phase difference monitoring scheme ensures that the acquired data is accurate and is not influenced by clutter, can realize large-phase-difference real-time early warning and reduce the occurrence of double-power switching accidents caused by overlarge phase difference to the maximum extent, and can solve the limitation that the current phase difference computing equipment has certain requirement on frequency or two channels have to have the same frequency. The utility model discloses the advantage: the inspection data is accurate, the safety is good, and the detection limitation is overcome.
Drawings
Fig. 1 is a block diagram of a phase difference detection apparatus according to an embodiment of the present invention;
fig. 2 is a flowchart of a phase difference detection apparatus according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The following detailed description is provided for the specific embodiments of the present invention.
As shown in fig. 1, a block diagram of a phase difference detection apparatus according to an embodiment of the present invention includes:
the hardware zero-crossing module is used for converting the alternating voltage to be measured into positive zero alternating voltage;
the signal processing module is connected with the hardware zero-crossing module and is used for converting the voltage into a signal type voltage used by the hardware zero-crossing module;
the jumping edge monitoring module is used for monitoring the jumping edge of the square wave between a high level and a low level and sending out a signal notice;
the high and low level monitoring module is connected with the jumping edge monitoring module and is used for carrying out timing judgment and storage on the high and low levels of the transmitted signals;
the filtering module is connected with the high and low level monitoring module and is used for filtering level jump caused by signal noise;
the phase difference monitoring module processes and summarizes the received data through calculation and logic execution programs to obtain phase difference data;
the communication module is used for transmitting the phase difference data to the outside;
and the power supply module is used for providing operation energy.
The embodiment of the utility model provides an in, with multichannel electrical data access signal processing module, carry out the signal transformation ratio by the voltage transformer among the signal processing module, the transformation ratio requires to be the voltage (like 10 KV) transformation ratio of normal operating 100V. Voltage transformation ratio coefficient = normal operating voltage/100; and the signal after the transformation ratio is accessed into a signal processing module to reduce and filter the voltage. Collected voltage and current are combined and arranged into signals of 0-3.3V which can be used by the data conversion module through the analog circuit. And sends the signal to a hardware zero crossing module. The hardware zero-crossing module compares data transmitted by the signal processing module with 1.65V through hardware, and the module converts a sine wave signal of 0-3.3V into a rectangular wave with the same frequency, wherein the high level of the rectangular wave is 3.3V, and the low level of the rectangular wave is 0V. And transmitting the converted signal into a high-low level monitoring module and a jumping edge monitoring module. After receiving the signal from the hardware zero-crossing module, the high-low level monitoring module performs high-low level sampling judgment on the signal at the interval of 1ms by the timer, continuously stores a plurality of historical data, puts the historical data into a one-dimensional data matrix, and transmits the one-dimensional data matrix to the filtering module for use. After receiving the signal from the hardware zero crossing module, the jump edge monitoring module sends a trigger signal to the filtering module if detecting that the interruption is triggered by the jump edge, and the filtering module filters the data. The filtering module receives the one-dimensional data matrix transmitted by the high-low level module, carries out mode filtering on the matrix, namely, checks all data in the one-dimensional data matrix one by one, if the data is high level, the mode high level counting value is added with one, if the data is low level, the mode low level counting value is added with one, compares the mode high level counting value with the mode low level counting value after all judgment is finished, and takes a larger value as a mode filtering result. After receiving the jump edge interrupt signal transmitted by the jump edge monitoring module, the filtering module judges the direction of the jump edge by combining the mode value of the high-low level module, namely if the mode value is high level, the jump edge jumps from high level to low level, otherwise, if the mode value is low level, the jump edge jumps from low level to high level. And transmitting the judgment result to the phase difference monitoring module. And the phase difference monitoring module records the value of the current timer after receiving the jump edge signal and the jump edge direction sent by the filtering module, and if the jump edge signal and the jump edge direction jump from the low level to the high level, the value is used as the high level jump phase data of the data. If the high level jumps to the low level, the low level jump phase data of the path of data is reformed. And performing subtraction with the phase data and corresponding channels of other channels, wherein channel 1 low level jump phase data-channel 2 low level jump phase data = phase difference between channel 2 and channel 1. Similarly, channel 1 high level jump phase data-channel 2 high level jump phase data = phase difference between channel 2 and channel 1. The phase difference monitoring scheme ensures that the acquired data is accurate and is not influenced by clutter, can realize large-phase-difference real-time early warning and reduce the occurrence of double-power switching accidents caused by overlarge phase difference to the maximum extent, and can solve the limitation that the current phase difference computing equipment has certain requirement on frequency or two channels have to have the same frequency.
As a preferred embodiment of the utility model, signal processing module includes voltage transformer and rectifier module, and voltage transformer is used for carrying out the scaling with high voltage signal to required signal amplitude within range, and rectifier module moves whole signal datum point, makes it not exceed the range of hardware zero passage module usable signal type. And the signal after the transformation ratio is connected into a rectification module to reduce and filter the voltage. The collected voltage and current are combined and arranged into signals which can be used by the data conversion module through the analog circuit. And sends the signal to a hardware zero crossing module.
As a preferred embodiment of the utility model, hardware zero passage module includes AD sample thief and voltage comparator, and the AD sample thief is used for gathering square wave voltage, and the voltage comparator is used for comparing the voltage signal that awaits measuring with reference voltage, realizes the rectification function. The AD sampler is used for carrying out discrete sampling on the converted square wave and transmitting a discrete sampling signal into a next required module.
As a preferred embodiment of the present invention, the jumping edge monitoring module includes a central processing unit and an external interrupt module, the central processing unit is used for processing signals and storing the jumping edge signals; the external interrupt module is used for transmitting the transition edge trigger signal to the filtering module.
As a preferred embodiment of the utility model, high low level monitoring module includes GPIO general purpose input/output module, central processing unit and timer module, and GPIO general purpose input/output module is used for reading by the level of monitoring signal, and central processing unit is used for handling and the level that the storage was monitored, and timer module realizes regularly carrying out the level judgement to the signal of monitoring.
As the utility model discloses a preferred embodiment, communication module includes RS485 communication module and general output module, and RS485 communication module is used for realizing the agreement transmission, and general output module is the departure point to the abnormal signal of the external receiving system of system.
As a preferred embodiment of the present invention, the phase difference detecting device further includes an additional module for implementing other functional modules outside the core function of the device. The additional module comprises a human-computer interaction module and an acousto-optic alarm module, the human-computer interaction module is used for debugging and setting related values of users, the acousto-optic alarm module is used for displaying the normal operation of the whole system, and if the operation state of the system goes wrong, the acousto-optic alarm module carries out acousto-optic prompt on the outside of the system.
As the utility model discloses a another kind of preferred embodiment, power module adopts the switching power supply scheme to supply power for entire system, uses the scene to be normal operating condition: 380V; therefore, the parameters of the voltage transformer in the signal processing module are 380: 100. The hardware zero-crossing module adopts an analog circuit mainly composed of an LM2091 voltage comparator and an AD sampler 12 carried by an STM32F49IGT6 singlechip. And the GPIO module, the central processing unit, the timer module and the external interrupt module in the high-low level monitoring module and the jumping edge monitoring module are all integrated by an STM32F429IGT6 singlechip. In the example, RS485 communication and a display screen are adopted as a man-machine interaction module. A buzzer and an LED lamp module are used as the sound-light alarm module. The system is connected in a mode that the input of a signal processing module is connected with the input to be measured, the ADC sampling module of the STM32F429IGT6 is connected with the output of the signal processing module, and the output of the ADC sampling module of the STM32F429IGT6 is connected with a central processing unit (COTEX-M kernel). And the central processing unit sends the serial port modulation information to the display screen module through RS485 communication for man-machine interaction. And the general input and output module of the STM32F429IGT6 is connected with the buzzer module and the LED module.
After multi-path voltage to be subjected to phase difference monitoring is connected to corresponding terminals, the whole system is subjected to alternating current 220V power supply, and human-computer interaction equipment is used for setting and measuring phase difference data between the two terminals, the timing of a universal input module of a high-low level monitoring module is 1ms, and a phase difference alarm threshold is 20 degrees. The entire preparation is completed.
Under the condition of normal operation, the voltage to be measured is firstly subjected to corresponding transformation ratio and adjustment through the signal processing module, in the example, the transformation ratio of 390V sinusoidal voltage after passing through the voltage transformer is 100V sinusoidal voltage signal, and the voltage is adjusted to be 1.5V sinusoidal signal with 1.65V as the zero reference through the analog circuit. And sending the processed signal to a hardware zero-crossing module, sampling the signal through an ADC (analog to digital converter), comparing the voltage of the sampled signal which is a sine signal with 1.65V through a voltage comparator in the hardware zero-crossing module, and outputting 3.3V by the hardware zero-crossing module if the value of the signal is greater than 1.65V. And if the value of the signal is less than 1.65V, the hardware zero-crossing module outputs 0V. And then the hardware zero-crossing module converts the sinusoidal signal into a rectangular wave signal, and transmits the rectangular wave signal into the high-low level monitoring module and the jumping edge monitoring module. After receiving the matrix wave signal, the high-low level monitoring module samples the rectangular wave according to the setting timing 1ms time of the human-computer interaction equipment, judges whether the rectangular wave belongs to a TTL high level or a TTL low level (the high level is greater than 2.4V, and the low level is less than 0.4V), records the judged value in a one-dimensional data matrix with the data length of 5 in real time, and gradually expands the data matrix along with the time until 5 values are expanded, and then continuously stores the count value of 0 from the head of the one-dimensional matrix. After receiving the matrix signal, the jump edge monitoring module sets the external interrupt module to be edge triggered through the external interrupt module, and then sends an interrupt signal to the central processing unit when high and low level jumps. The interrupt system of the central processing unit forces the CPU to suspend the human task being executed and then enters the interrupt program for processing; after the interrupt processing is completed, execution continues at the return to the interrupted program. After receiving an interrupt signal sent by a jumping edge monitoring module, a filtering module jumps to an interrupt module part, firstly detects whether the mode of a voltage signal of the channel in a one-dimensional data matrix stored by a high-low level monitoring module is high level or low level, and if the mode is high level, the jumping edge at the moment can be judged to jump from low level to high level; if the current level is low level, the jumping edge at the moment can be judged to jump from high level to low level, and the information is sent to the phase difference monitoring module. And after receiving the jump information, the phase difference monitoring module stores the real-time running value of the timer in the phase data buffer of the channel, and if the jump information is a high-level jump low-level, the real-time running value of the timer is stored in the high-level jump low-level phase data buffer of the channel. And if the jump information is the low level jump high level, storing the low level jump high level phase data buffer of the channel. If the channel is the channel needing to calculate the phase difference, the phase data buffer of the channel is differenced with the corresponding jump phase data buffer of the reference channel (namely, the other channel for phase difference). Namely, the difference is made between the high level jump low level phase data buffer of the channel to be calculated and the high level jump low level phase data buffer of the reference channel. The low level jump high level fragrance data buffer of the channel to be calculated is subtracted from the low level jump high level phase data buffer of the reference channel. The interpolation is the time difference when the two channels pass through zero, mathematical identity transformation is carried out on the time difference to obtain a phase difference value, the magnitude of the phase difference and a phase difference alarm threshold value set by a human-computer interaction module is judged, if the phase difference is greater than the phase difference alarm threshold value, a buzzer module and an LED lamp module are triggered to prompt that the phase difference is abnormal, and the phase difference value is transmitted to the human-computer interaction module through a communication module to be displayed.
The embodiment of the present invention further provides a phase difference detection method, which is applied to the above phase difference detection device, wherein the phase difference detection method comprises:
the signal processing module receives the voltage to reduce and filter, 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 carries out high and low level sampling judgment on the signal, continuously stores a plurality of historical data, puts the historical data into a one-dimensional data matrix, and transmits the one-dimensional data matrix to the filtering module for use;
the jumping edge monitoring module receives the signal and judges triggering interruption, sends a triggering signal to the filtering module, and the filtering module filters data and transmits a judgment result to the phase difference monitoring module.
Step 1: and (3) connecting the multi-path electrical data into the signal processing module, and performing signal transformation ratio by a voltage transformer in the signal processing module, wherein the transformation ratio is required to be 100V for the voltage (such as 10 KV) of normal operation. Voltage transformation ratio coefficient = normal operating voltage/100; and the signal after the transformation ratio is connected into a rectification module to reduce and filter the voltage. Collected voltage and current are combined and arranged into signals of 0-3.3V which can be used by the data conversion module through the analog circuit. And sends the signal to a hardware zero crossing module.
Step 2: the hardware zero-crossing module compares 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 magnitude of two voltages, when the voltage of a positive input end is higher than that of a negative input end, the voltage comparator outputs a high level, when the voltage of the positive input end is lower than that of the negative input end, the voltage comparator outputs a low level, and the module converts a sine wave signal of 0-3.3V into a rectangular wave with the same frequency, wherein the rectangular high level is 3.3V, and the low level is 0V. And transmitting the converted signal into a high-low level monitoring module and a jumping edge monitoring module.
And step 3: after receiving the signal from the hardware zero-crossing module, the high-low level monitoring module performs high-low level sampling judgment on the signal at the interval of 1ms by the timer, continuously stores a plurality of historical data, puts the historical data into a one-dimensional data matrix, and transmits the one-dimensional data matrix to the filtering module for use. After the jumping edge monitoring module receives the signal from the hardware zero crossing module, the external interrupt module detects whether to trigger interrupt, if the external interrupt module detects that the external interrupt is triggered by the jumping edge, the external interrupt module sends a trigger signal to the filtering module, and the filtering module filters the data.
And 4, step 4: the filtering module receives the one-dimensional data matrix transmitted by the high-low level module, carries out mode filtering on the matrix, namely, checks all data in the one-dimensional data matrix one by one, if the data is high level, the mode high level counting value is added with one, if the data is low level, the mode low level counting value is added with one, compares the mode high level counting value with the mode low level counting value after all judgment is finished, and takes a larger value as a mode filtering result. After receiving the jump edge interrupt signal transmitted by the jump edge monitoring module, the filtering module judges the direction of the jump edge by combining the mode value of the high-low level module, namely if the mode value is high level, the jump edge jumps from high level to low level, otherwise, if the mode value is low level, the jump edge jumps from low level to high level. And transmitting the judgment result to the phase difference monitoring module.
And 5: and the phase difference monitoring module records the value of the current timer after receiving the jump edge signal and the jump edge direction sent by the filtering module, and if the jump edge signal and the jump edge direction jump from the low level to the high level, the value is used as the high level jump phase data of the data. If the high level jumps to the low level, the low level jump phase data of the path of data is reformed. And performing subtraction with the phase data and corresponding channels of other channels, wherein channel 1 low level jump phase data-channel 2 low level jump phase data = phase difference between channel 2 and channel 1. Similarly, channel 1 high level jump phase data-channel 2 high level jump phase data = phase difference between channel 2 and channel 1.
The above description is only exemplary of the present invention and should not be taken as limiting the scope of the present invention, as any modifications, equivalents, improvements and the like made within the spirit and principles of the present invention are intended to be included within the scope of the present invention.
Claims (8)
1. A phase difference detection device, characterized by comprising:
the hardware zero-crossing module is used for converting the alternating voltage to be measured into positive zero alternating square wave voltage;
the signal processing module is connected with the hardware zero-crossing module and used for converting the voltage into a signal type voltage used by the hardware zero-crossing module;
the jumping edge monitoring module is used for monitoring the jumping edge of the square wave between a high level and a low level and sending out a signal notice;
the high and low level monitoring module is connected with the jumping edge monitoring module and is used for carrying out timing judgment and storage on the high and low levels of the transmitted signals;
the filtering module is connected with the high and low level monitoring module and is used for filtering level jump caused by signal noise;
the phase difference monitoring module processes and summarizes the received data through calculation and logic execution programs to obtain phase difference data;
and the power supply module is used for providing operation energy.
2. A phase difference detector according to claim 1, wherein said signal processing module comprises a voltage transformer for scaling the high voltage signal to within a desired signal amplitude range and a rectification module for shifting the entire signal reference point to be no more than the range of signal types available to the hardware zero crossing module.
3. The apparatus according to claim 1, wherein the hardware zero-crossing module comprises an AD sampler for collecting a square wave voltage and a voltage comparator for comparing the voltage signal to be measured with a reference voltage to implement a rectification function.
4. The apparatus according to claim 1, wherein the transition edge monitoring module comprises a central processing unit and an external interrupt module, the central processing unit is configured to process the signal and store the transition edge signal; the external interrupt module is used for transmitting the transition edge trigger signal to the filtering module.
5. The apparatus of claim 1, wherein the high/low level monitoring module comprises a GPIO general purpose input/output module for reading the level of the monitored signal, a central processing unit for processing and storing the monitored level, and a timer module for performing a timing determination on the level of the monitored signal.
6. The apparatus of claim 1, further comprising a communication module, wherein the communication module comprises an RS485 communication module and a general output module, the RS485 communication module is used for protocol transmission, and the general output module is a point for receiving abnormal signals of the system outside the system.
7. A phase difference detection device according to any of claims 1-6 and further comprising additional modules.
8. The apparatus according to claim 7, wherein the additional modules comprise a human-computer interaction module for human operator to debug and adjust the related value, and an audible and visual alarm module for displaying the normal operation of the whole system.
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