Distribution network fault arc detection device
Technical Field
The invention relates to the field of intelligent power distribution and utilization, in particular to a power distribution network fault arc detection device.
Background
The arc combustion is accompanied by physical phenomena such as sound, light, heat, and electromagnetic radiation. The use of the above features is not effective in the detection of fault arcs in building electrical and long lines, and sensors cannot be installed because the location of a major fault in a line in a building cannot be determined. Meanwhile, a large amount of normal electric arc phenomena exist in the line of the power distribution network, and the quality of the electric arc cannot be distinguished through the physical phenomena.
The current distribution line fault arc detection method depends on the fault arc voltage and current waveform characteristics, and as the number of nonlinear electric equipment such as variable frequency household appliances, LED lighting lamps, induction cookers and the like increases, the normal working current of the circuit is very similar to the fault arc current waveform characteristics, so that the accuracy of arc fault detection is seriously influenced. Although the arc fault detection accuracy can be improved by adopting multiple complex signal processing methods such as Fourier transform, wavelet transform, support vector machine and neural network, the methods have relatively high requirements on hardware or have very complex operation and are difficult to realize in engineering. Therefore, the problems of limited installation position, poor noise interference resistance, difficult identification of effective signals and the like exist.
Disclosure of Invention
The invention aims to provide a power distribution network fault arc detection device, which improves the anti-noise interference and the arc fault detection precision and effectively detects fault arcs in long-distance power supply lines.
The technical purpose of the invention is realized by the following technical scheme:
a power distribution network fault arc detection device comprises a unit A and a unit B, wherein the A, B units respectively comprise a power supply module, a PLC power line carrier communication module, a sampling module, a wireless communication module and a main controller, wherein the unit A is connected with an output signal interface for driving a circuit breaker to trip;
the power supply module provides electric energy support for the operation of the device; the sampling module integrates voltage acquisition, filtering and calculation functions and sends sampling data to the main controller; the PLC power line carrier communication module realizes bidirectional transparent transmission of power line carrier signals and device main controller signals; the wireless communication module is used for being in communication connection with the Internet and the main controller;
the main controller is internally provided with a fault arc detection algorithm, the A unit runs an Ai program, the B unit runs a Bi program, and the A unit and the B unit work cooperatively after being paired.
Further, the power module includes an AC/DC, DC/DC section with isolation.
Furthermore, the wireless communication module utilizes a wireless communication technology with high speed, long distance and strong interference resistance.
Furthermore, the main controller takes the unit A for running the Ai program as a host computer and the unit B for running the Bi program as a slave computer, and the unit A and the unit B are matched and then work cooperatively, so that the fault arc detection result is judged in the unit A.
Further, the Ai program flow is:
step 1: initializing operation fixed values of the unit A, wherein the operation fixed values comprise T1max, T2max and tDelay parameters;
step 2: the A unit carrier communication counter T1 is cleared;
step 3: issue "query instruction 1" to B Unit; after waiting for tDelay seconds, the variable T1 increments itself once; check "response data 1" in the receive buffer;
step 4: judging whether the conditions of 'T1 > T1 max' and 'no receiving of valid response data 1' are satisfied, if so, executing step5, otherwise, executing step 10;
step 5: the wireless communication counter T2 of the unit A is cleared;
step 6: starting wireless communication, and sending 'inquiry instruction 2' to the B unit; the variable T2 increments once; checking the response data 2 in the receiving buffer;
step 7: judging whether 'valid response data 2 is received', if so, executing step8, otherwise, executing step 11;
step 8: analyzing the received effective response data 2, and judging whether the effective value of 'VA > VB' is met, wherein VA is the effective value of the fundamental voltage of the unit A, VB is the effective value of the fundamental voltage of the unit B, if yes, step9 is executed, otherwise, step1 is executed;
step 9: the program obtains the conclusion that the arc fault occurs, a tripping command is sent to the circuit breaker, and the program is ended;
step 10: judging whether 'valid response data 1 is received', if so, executing Step2, otherwise, executing Step 3;
step 11: judging whether 'T2 > T2 max' is met, if so, executing step12, and otherwise, executing step 6;
step 12: the program concludes that "line break" has occurred, and the program ends.
Further, the Bi program flow is:
step' 1: initializing operation fixed values of the B unit, wherein the operation fixed values comprise parameters K1max, K2max, tDelay1, tDelay2, M, storage arrays 1 and arrays 2;
step' 2: the B unit carrier communication counter K1 is cleared;
step' 3: starting power line carrier communication to receive 'inquiry instruction 1'; after the delay waiting time tDelay seconds, the variable K1 is increased by itself; storing the received data in a storage Array 1;
step' 4: judging whether the 'K1 > K1max is met and the carrier wave does not receive the inquiry command 1'; if yes, step'5 is executed; otherwise, step'10 is executed;
step' 5: the B unit wireless communication counter K2 is cleared;
step' 6: starting wireless communication reception "inquiry command 2"; after waiting time tDelay1 seconds, the variable K2 increments itself once; storing the received data in a storage Array 2;
step' 7: judging whether the 'receiving the query instruction 2' is met, if so, executing step '8, otherwise, executing step' 11;
step' 8: sending the response data 2 to the unit A for 1 time at the interval tDelay2, sending the response data for M times, and ending the program;
step' 9: send a valid "response data 1" to unit A;
step' 10: judging whether the carrier wave receiving inquiry instruction 1 is met, if so, executing step '9, otherwise, executing step' 3;
step' 11: and judging whether the 'K2 > K2 max' is met, if so, executing step '1, and otherwise, executing step' 6.
Further, the semantics of "query instruction 1" are formed as follows: A-4A2-C0F-FFE-CRC, A represents the device type of the A unit, 4A2 represents the device ID of the A unit as 1186, C0F represents the ID of the B unit as 3087, FFE represents the pairwise password as 4094, and CRC represents the check code.
Further, the semantics of "query instruction 2" are formed as follows: A-4A2-C0F-01-FFE-CRC, wherein A represents the equipment type of the unit A, 4A2 represents the equipment ID of the unit A to be 1186, C0F represents the ID of the unit B to be 3087, 01 represents the inquiry data type to be a fundamental voltage effective value, FFE represents the pairing password to be 4094, and CRC represents a check code.
Further, the semantics of "response data 1" are constituted as: B-4A2-C0F-FFE-CRC, B represents the device type of the B unit, 4A2 represents the device ID of the A unit as 1186, C0F represents the ID of the B unit as 3087, FFE represents the pairwise password as 4094, and CRC represents the check code.
Further, the semantics of "response data 2" are constituted as: B-4A2-C0F-8FA-FFE-CRC, wherein B represents the equipment type of the B unit, 4A2 represents the equipment ID of the A unit as 1186, C0F represents the ID of the B unit as 3087, 8FA represents the response fundamental wave voltage effective value data as 229.8V, FFE represents the pairing password as 4094, and CRC represents the check code.
In conclusion, the invention has the following beneficial effects:
by the method, the problems of limited installation position, poor noise interference resistance, difficult identification of effective signals and the like in the power distribution network arc detection can be solved, the accuracy of noise interference resistance and arc fault detection is improved, and the fault arc between the unit A and the unit B in a long-distance power supply line is effectively detected.
Drawings
FIG. 1 is a schematic view of a fault arc protection device topology in accordance with the present invention;
fig. 2 is a flowchart of the procedure of the Ai unit and Bi unit of the present invention.
Detailed Description
The following further describes the embodiments of the present invention with reference to the drawings, and the present embodiment is not to be construed as limiting the invention.
Although the procedures in the present invention are arranged in steps, the procedures are not limited to the order of the steps, and the relative order of the steps may be adjusted unless the judgment process and the processing result are explicitly described.
A power distribution network fault arc detection device comprises an A unit and a B unit, as shown in figure 1, the method comprises an Ai program running in the A unit and a Bi program running in the B unit, and the A unit and the B unit work cooperatively after being paired.
A. The unit B consists of a power supply module, a PLC power line carrier communication module, a sampling module, a wireless communication module and a main controller, and the main controller of the unit A is connected with an output signal interface for driving the circuit breaker to trip. Wherein: the power supply module provides electric energy support for the operation of the device; the PLC power line carrier communication module is communicated with the main controller so as to realize bidirectional transparent transmission of power line carrier signals and device main controller signals; the main controller is internally provided with a fault arc detection algorithm which is a control center of the power distribution network fault arc detection device, the A unit runs an Ai program, the B unit runs a Bi program, and the A unit and the B unit work cooperatively after being paired; the sampling module integrates voltage acquisition, filtering and high-precision calculation functions and sends sampling data to the main controller; the wireless communication module is connected with the main controller and the internet.
The power module is composed of an AC/DC part and a DC/DC part with an isolation function, provides electric energy support for the operation of the device, and is generally used for obtaining a 12V direct-current power supply through alternating current and direct current conversion of commercial power and then obtaining 5V and 3.3V direct-current power supplies through voltage transformation by utilizing a voltage management chip or the isolation power module.
The PLC power line carrier communication module realizes bidirectional transparent transmission of power line carrier signals and device main controller signals through a modem, and encryption processing can be carried out in transparent data according to the requirement on safety.
The sampling module integrates voltage acquisition, filtering and high-precision calculation functions, and can be realized by using technologies such as FPGA, DSP and the like.
The wireless communication module utilizes a wireless communication technology with high speed, long distance and strong anti-jamming capability, such as ZigBee, Wi-Fi, 4G, 5G and the like.
The main controller takes the A unit running the Ai program as a main machine and the B unit running the Bi program as a slave machine, the A unit and the B unit work cooperatively after being paired, and the judgment of the fault arc detection result is made in the A unit. The hardware of the main controller adopts a high-performance DSP or an ARM.
As shown in fig. 2, the Ai program running in the unit a has the flow:
step 1: initializing parameters such as operation fixed values T1max, T2max, tDelay and the like of the unit A;
step 2: the A unit carrier communication counter T1 is cleared;
step 3: issue "query instruction 1" to B Unit; after waiting for tDelay seconds, the variable T1 increments itself once; check "response data 1" in the receive buffer;
step 4: judging whether the conditions of 'T1 > T1 max' and 'no receiving of valid response data 1' are satisfied, if so, executing step5, otherwise, executing step 10;
step 5: the wireless communication counter T2 of the unit A is cleared;
step 6: starting wireless communication, and sending 'inquiry instruction 2' to the B unit; the variable T2 increments once; checking the response data 2 in the receiving buffer;
step 7: judging whether 'valid response data 2 is received', if so, executing step8, otherwise, executing step 11;
step 8: analyzing the received effective response data 2, and judging whether the effective value of 'VA > VB' is met, wherein VA is the effective value of the fundamental voltage of the unit A, VB is the effective value of the fundamental voltage of the unit B, if yes, step9 is executed, otherwise, step1 is executed;
step 9: the program obtains the conclusion that the arc fault occurs, a tripping command is sent to the circuit breaker, and the program is ended;
step 10: judging whether 'valid response data 1 is received', if so, executing step2, otherwise, executing step 3;
step 11: judging whether 'T2 > T2 max' is met, if so, executing step12, and otherwise, executing step 6;
step 12: the program concludes that "line break" has occurred, and the program ends.
The process of the Bi program running in the unit B is as follows:
step' 1: initializing operation fixed values of the B unit, wherein the operation fixed values comprise parameters K1max, K2max, tDelay1, tDelay2, M, storage arrays 1 and arrays 2;
step' 2: the B unit carrier communication counter K1 is cleared;
step' 3: starting power line carrier communication to receive 'inquiry instruction 1'; after the delay waiting time tDelay seconds, the variable K1 is increased by itself; storing the received data in a storage Array 1;
step' 4: judging whether 'K1 > K1max is met and the carrier wave does not receive the query instruction 1', if so, executing step '5, otherwise, executing step' 10;
step' 5: the B unit wireless communication counter K2 is cleared;
step' 6: starting wireless communication reception "inquiry command 2"; after waiting time tDelay1 seconds, the variable K2 increments itself once; storing the received data in a storage Array 2;
step' 7: judging whether the 'receiving the query instruction 2' is met, if so, executing step '8, otherwise, executing step' 11;
step' 8: sending the response data 2 to the unit A for 1 time at the interval tDelay2, sending the response data for M times, and ending the program;
step' 9: send a valid "response data 1" to unit A;
step' 10: judging whether the carrier wave receiving inquiry instruction 1 is met, if so, executing step '9, otherwise, executing step' 3;
step' 11: and judging whether the 'K2 > K2 max' is met, if so, executing step '1, and otherwise, executing step' 6.
The semantics of "query instruction 1" are formed as follows: A-4A2-C0F-FFE-CRC, A represents the device type of the A unit, 4A2 represents the device ID of the A unit as 1186, C0F represents the ID of the B unit as 3087, FFE represents the pairwise password as 4094, and CRC represents the check code.
The semantics of "query 2" are formed as: A-4A2-C0F-01-FFE-CRC, wherein A represents the equipment type of the unit A, 4A2 represents the equipment ID of the unit A to be 1186, C0F represents the ID of the unit B to be 3087, 01 represents the inquiry data type to be a fundamental voltage effective value, FFE represents the pairing password to be 4094, and CRC represents a check code.
The semantics of "response data 1" are constituted as: B-4A2-C0F-FFE-CRC, B represents the device type of the B unit, 4A2 represents the device ID of the A unit as 1186, C0F represents the ID of the B unit as 3087, FFE represents the pairwise password as 4094, and CRC represents the check code.
The semantics of "response data 2" are constituted as: B-4A2-C0F-8FA-FFE-CRC, wherein B represents the equipment type of the B unit, 4A2 represents the equipment ID of the A unit as 1186, C0F represents the ID of the B unit as 3087, 8FA represents the response fundamental wave voltage effective value data as 229.8V, FFE represents the pairing password as 4094, and CRC represents the check code.
While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the invention.