CN115508589A - Automatic line changing method between relay protection device and relay protection tester - Google Patents

Abstract

An automatic line change method between a relay protection device and a relay protection tester, comprising: a switching expansion device for expanding at least two sets of input power sources of the relay protection tester into at least three sets of output current sources, And the output current source is sent to the relay protection device; the background computer is used to control the switching expansion device and the relay protection tester. The automatic line changing method between the relay protection device and the relay protection tester of the present invention does not need to change the line during the test, thereby reducing the workload and avoiding mistakes in line changing, and providing conditions for fully automatic testing.

Description

A method for automatically changing wires between a relay protection device and a relay protection tester

technical field

The invention relates to the technical field of power system secondary control and protection equipment, in particular to an automatic line change method between a relay protection device and a relay protection tester.

Background technique

There are many types of secondary control and protection equipment in the power system, and the wiring methods of each equipment are different. Existing test equipment such as those produced by manufacturers such as Omicron, Onlly, and Bodian, have the following two problems in most of the existing equipment: 1) There is only one or two sets of analog input, and three or four sets of output currents are required for the protection of a large number of branches, such as transformer protection and busbar protection, and the test line needs to be replaced frequently during the test. When testing software such as RTbasic, it cannot fully automatically test; 2) The output capacity of a single group of analog quantities is small, and some protections with a large amount of current applied, such as the fixed value error verification when the current is set to 100A, cannot meet the output requirements. The demand also needs to be solved by current parallel output.

At present, in the case of a large number of current groups required for the test, the test is performed through a dedicated extended test device, and in the case of a large output current amplitude required for the test, the test is performed through the parallel connection of the current output. The above test method also has the following disadvantages: 1) it cannot meet the requirements of automatic testing. In the prior art, in the case of automatic testing, it is necessary to suspend the automatic testing and manually change the line, which reduces the testing efficiency and increases the workload of the testers. 2) Manual line change reduces the reliability of correct wiring, and frequent line change will lead to wrong connection, which increases the risk of testing

Therefore, in view of the deficiencies of the prior art, it is necessary to provide an automatic line change method between the relay protection device and the relay protection tester to solve the deficiencies of the prior art.

Contents of the invention

The purpose of the present invention is to avoid the disadvantages of the prior art and provide an automatic line change method between a relay protection device and a relay protection tester. The automatic wire changing method between the relay protection device and the relay protection tester can perform all tests without changing wires on the existing testing equipment.

Above-mentioned purpose of the present invention is achieved through the following technical measures:

A method for automatic line change between a relay protection device and a relay protection tester is provided, which includes:

A switching expansion device, which is used to expand at least two sets of input power sources of the relay protection tester into at least three sets of output current sources, and deliver the output current sources to the relay protection device;

The background computer is used to control the switching expansion device and the relay protection tester.

Preferably, the switching expansion device is provided with an input switch group, an intermediate switch group and an output switch group, the input switch group is connected to a relay protection tester, and the input switch group and the output switch group are respectively connected to the intermediate The switch group is connected, and the input switch group is connected with the relay protection device.

Preferably, the above-mentioned input switch group is provided with a switch 1-1 and a switch 2-1.

Preferably, the above-mentioned intermediate switch group is provided with a switch 1-2, a switch 1-3, a switch 2-2 and a switch 2-3.

Preferably, the above input switch group is provided with a switch 1-4, a switch 1-5, a switch 1-6, a switch 2-4, a switch 2-5 and a switch 2-6.

The A terminal, B terminal, C terminal and H terminal of the switch 1-1 are respectively connected to one of the input current sources of the relay protection tester, and the A terminal, B terminal, C terminal and H terminal of the switch 2-1 are respectively connected to the Another set of input current source connections for the relay tester.

The first contact end of the switch 1-1 and the A end of the switch 1-2 and the A end of the switch 1-3, the second contact end of the switch 1-1 and the B end of the switch 1-2 and the switch 1-3 The B terminal of the switch 1-1, the third contact terminal of the switch 1-1 and the C terminal of the switch 1-2 and the A terminal of the switch 2-3, the fourth contact terminal of the switch 1-1 and the H terminal of the switch 1-2 and Terminal B of switch 2-3.

The first contact end of switch 2-1 and the A end of switch 2-2 and the C end of switch 1-3, the second contact end of switch 2-1 and the B end of switch 2-2 and switch 1-3 The H end of the switch 2-1, the third contact end of the switch 2-1 and the C end of the switch 2-2 and the C end of the switch 2-3, the fourth contact end of the switch 2-1 and the H end of the switch 2-2 and H terminal of switch 2-3.

The first contact end of the switch 1-2 is connected with the first contact end of the switch 1-2, the A end of the switch 1-4, the A end of the switch 1-5 and the A end of the switch 1-6, and the switch 1- The second contact end of 2 is connected with the second contact end of switch 1-2, the B end of switch 1-4, the B end of switch 1-5 and the B end of switch 1-6, and the second contact end of switch 1-2 The three contact terminals are connected with the third contact terminal of switch 1-2, the C terminal of switch 1-4, the C terminal of switch 1-5 and the C terminal of switch 1-6, and the fourth contact of switch 1-2 The terminal is connected with the first contact terminal of the switch 2-3, the H terminal of the switch 1-4, the H terminal of the switch 1-5 and the H terminal of the switch 1-6.

The first contact end, the second contact end, the third contact end and the fourth contact end of the switch 1-2 are connected in parallel, and the first contact end, the second contact end, and the third contact end of the switch 2-3 are connected in parallel. The point end and the fourth contact end are connected in parallel.

The first contact end of the switch 2-2 is connected with the A end of the switch 2-4, the A end of the switch 2-5, and the A end of the switch 2-6, and the second contact end of the switch 2-2 is connected with the switch 2- The B terminal of 4, the B terminal of switch 2-5, and the B terminal of switch 2-6 are connected, and the third contact terminal of switch 2-2 is connected with the C terminal of switch 2-4, the C terminal of switch 2-5, and the switch The C terminal of the switch 2-6 is connected, and the fourth contact terminal of the switch 2-2 is connected with the H terminal of the switch 2-4, the H terminal of the switch 2-5, and the H terminal of the switch 2-6.

The first contact end of the switch 1-4 is connected with the first contact end of the switch 2-4, the second contact end of the switch 1-4 is connected with the second contact end of the switch 2-4, and the switch 1-4 The third contact terminal of the switch 2-4 is connected with the third contact terminal of the switch 2-4, and the fourth contact terminal of the switch 1-4 is connected with the fourth contact terminal of the switch 2-4.

The first contact end of switch 1-5 is connected with the first contact end of switch 2-5, the second contact end of switch 1-5 is connected with the second contact end of switch 2-5, switch 1-5 The third contact end of the switch is connected to the third contact end of the switch 2-5, and the fourth contact end of the switch 1-5 is connected to the fourth contact end of the switch 2-5.

The first contact end of switch 1-6 is connected with the first contact end of switch 2-6, the second contact end of switch 1-6 is connected with the second contact end of switch 2-6, switch 1-6 The third contact end of the switch is connected to the third contact end of the switch 2-6, and the fourth contact end of the switch 1-6 is connected to the fourth contact end of the switch 2-6.

The first contact end, the second contact end, the third contact end and the fourth contact end of the switches 1-4 constitute the first group of output current sources of the switching expansion device and are connected to the electric protection device.

The first contact end, the second contact end, the third contact end and the fourth contact end of the switches 1-5 constitute the second group of output current sources of the switching expansion device and are connected to the electric protection device.

The first contact end, the second contact end, the third contact end and the fourth contact end of the switches 1-6 constitute the third group of output current sources of the switching expansion device and are connected to the electric protection device.

Preferably, the background computer communicates with the relay protection tester through a network port.

Preferably, the above-mentioned switching expansion device is connected to the relay protection tester through a test line, so that the current output by the relay protection tester is connected to the switching expansion device, and at the same time, the extended current interface is connected to the relay protection device .

Preferably, the background computer communicates with the switching extension device through a serial port.

Preferably, the background computer communicates with the relay protection device through a network port, so as to receive test information of the relay protection device.

Preferably, the above-mentioned background computer uses the Modbus protocol to control the switching expansion device.

Preferably, the above switching expansion device is also provided with a microcontroller and a control loop for controlling the input switch group, the intermediate switch group and the output switch group, and the microcontroller and the background computer are connected through a serial port To communicate, the microcontroller and the control loop are controlled via DO.

Preferably, the model of the above-mentioned relay protection tester is OMICRON CMC356.

Preferably, the above switch 1-1, switch 2-1, switch 1-2, switch 1-3, switch 2-2 and switch 2-3, switch 1-4, switch 1-5, switch 1-6, switch 2-4, switch 2-5 and switch 2-6 are all four-contact switches.

An automatic line change method between a relay protection device and a relay protection tester of the present invention is provided with: a switching expansion device for expanding at least two sets of input power sources of the relay protection tester into at least three sets of outputs The current source is used to deliver the output current source to the relay protection device; the background computer is used to control the switching expansion device and the relay protection tester. The automatic line changing method between the relay protection device and the relay protection tester of the present invention does not need to change the line during the test, thereby reducing the workload and avoiding mistakes in line changing, and providing conditions for fully automatic testing.

Description of drawings

The present invention will be further described by using the accompanying drawings, but the content in the accompanying drawings does not constitute any limitation to the present invention.

Fig. 1 is a schematic diagram of the system connection of an automatic line change method between a relay protection device and a relay protection tester.

Fig. 2 is a schematic diagram of the connection of the switching extension device.

Fig. 3 is a schematic circuit diagram of the control loop.

In Figures 1 to 3, including:

Switch extension device 100, switch 1-1 101, switch 2-1 102, switch 1-2 103, switch 1-3 104, switch 2-2 105, switch 2-3 106, switch 1-4 107, switch 1- 5 108, switch 1-6 109, switch 2-4 110, switch 2-5111, switch 2-6 112,

Background computer 200, relay protection tester 300, relay protection device 400.

detailed description

The technical solution of the present invention will be further described in conjunction with the following examples.

Example 1.

A method for realizing an automatic line change between a relay protection device 400 and a tester, as shown in Figures 1 and 2, is provided with:

The switching expansion device 100 is used to expand at least two sets of input power sources of the relay protection tester 300 into at least three sets of output current sources, and deliver the output current sources to the relay protection device 400 .

The background computer 200 is used to control the switch expansion device 100 and the relay protection tester 300 .

The background computer 200 of the present invention communicates with the relay protection tester 300 through the network port. It should be noted that the actual mode between the background computer 200 and the relay protection tester 300 is specifically controlled according to the interface program provided by the manufacturer of the relay protection tester 300 .

The switching extension device 100 is connected to the relay protection tester 300 through a test line, so that the current output by the relay protection tester 300 is connected to the switching extension device 100, and at the same time, the extended current interface is connected to the relay protection device 400.

The background computer 200 communicates with the switch extension device 100 through a serial port.

The background computer 200 communicates with the relay protection device 400 through the network port, so as to receive the test information of the relay protection device 400 . The background computer 200 controls the switching expansion device 100 using the Modbus protocol.

It should be noted that the switching expansion device 100 of the present invention can expand the input power of the relay protection tester 300 into more output currents, and these output currents are all parallel outputs of the input power, thus meeting the requirements of multi-current, large current output requirements. The output current may be connected to a single protective relay device 400, or may be connected to multiple protective relay devices 400, depending on the actual situation.

The switching expansion device 100 is provided with an input switch group, an intermediate switch group and an output switch group, the input switch group is connected with the relay protection tester 300, and the input switch group and the output switch group are respectively connected to the intermediate switch group connected, the input switch group is connected with the relay protection device 400 .

It should be noted that the input switch group of the present invention is used to directly control the current source of the relay protection tester 300 . The role of the middle switch group is to be able to apply to the situation of 300 large current output of some relay protection testers.

The specific input switch group of the present invention is provided with switch 1-1 101 and switch 2-1 102, and the middle switch group is provided with switch 1-2 103, switch 1-3 104, switch 2-2 105 and switch 2-3 106 , the input switch group is provided with a switch 1-4 107, a switch 1-5 108, a switch 1-6 109, a switch 2-4 110, a switch 2-5 111 and a switch 2-6 112. Switch 1-1101, Switch 2-1 102, Switch 1-2 103, Switch 1-3 104, Switch 2-2 105 and Switch 2-3 106, Switch 1-4 107, Switch 1-5 108, Switch 1- 6 109, switch 2-4 110, switch 2-5 111 and switch 2-6 112 are all four-contact switches.

Specifically, the A terminal, B terminal, C terminal and H terminal of the switch 1-1 101 are respectively connected to one group of input current sources of the relay protection tester 300, and the A terminal, B terminal, C terminal of the switch 2-1 102 The terminals H and H are respectively connected to another set of input current sources of the relay protection tester 300 .

The first contact end of the switch 1-1 101 is connected with the A end of the switch 1-2 103 and the A end of the switch 1-3 104, the second contact end of the switch 1-1101 is connected with the B end of the switch 1-2 103 and The B terminal of switch 1-3 104, the third contact terminal of switch 1-1 101, the C terminal of switch 1-2 103 and the A terminal of switch 2-3 106, the fourth contact terminal of switch 1-1 101 With the H terminal of the switch 1-2 103 and the B terminal of the switch 2-3 106 .

The first contact terminal of the switch 2-1 102 is connected with the A terminal of the switch 2-2 105 and the C terminal of the switch 1-3 104, the second contact terminal of the switch 2-1102 is connected with the B terminal of the switch 2-2 105 and H terminal of switch 1-3 104, third contact terminal of switch 2-1 102, C terminal of switch 2-2 105 and C terminal of switch 2-3 106, fourth contact terminal of switch 2-1 102 With the H terminal of the switch 2-2 105 and the H terminal of the switch 2-3 106.

The first contact terminal of switch 1-2 103 and the first contact terminal of switch 1-2 103, the A terminal of switch 1-4 107, the A terminal of switch 1-5 108 and the A terminal of switch 1-6 109 Connection, the second contact terminal of switch 1-2 103 and the second contact terminal of switch 1-2 103, the B terminal of switch 1-4 107, the B terminal of switch 1-5 108 and the B terminal of switch 1-6 109 The B end is connected, the third contact end of the switch 1-2 103 is connected with the third contact end of the switch 1-2 103, the C end of the switch 1-4 107, the C end of the switch 1-5 108 and the switch 1-6 The C terminal of 109 is connected, the fourth contact terminal of switch 1-2 103 is connected with the first contact terminal of switch 2-3 106, the H terminal of switch 1-4 107, the H terminal of switch 1-5 108 and switch 1 -6 H-terminal connection of 109.

The first contact end, the second contact end, the third contact end and the fourth contact end of the switch 1-2 103 are connected in parallel, and the first contact end, the second contact end, and the third contact end of the switch 2-3106 are connected in parallel. The contact end and the fourth contact end are connected in parallel.

The first contact end of the switch 2-2 105 is connected with the A end of the switch 2-4 110, the A end of the switch 2-5 111, and the A end of the switch 2-6112, and the second contact end of the switch 2-2 105 Connect with the B terminal of the switch 2-4 110, the B terminal of the switch 2-5 111, the B terminal of the switch 2-6 112, the third contact terminal of the switch 2-2 105 and the C terminal of the switch 2-4 110, The C end of the switch 2-5 111 and the C end of the switch 2-6 112 are connected, the fourth contact end of the switch 2-2 105 is connected with the H end of the switch 2-4 110, the H end of the switch 2-5 111, the switch 2-6 H-terminal connections of 112.

The first contact end of the switch 1-4 107 is connected to the first contact end of the switch 2-4 110, the second contact end of the switch 1-4 107 is connected to the second contact end of the switch 2-4 110, The third contact end of the switch 1-4 107 is connected to the third contact end of the switch 2-4 110 , and the fourth contact end of the switch 1-4 107 is connected to the fourth contact end of the switch 2-4 110 .

The first contact end of the switch 1-5 108 is connected to the first contact end of the switch 2-5 111, the second contact end of the switch 1-5 108 is connected to the second contact end of the switch 2-5 111, The third contact end of the switch 1-5 108 is connected to the third contact end of the switch 2-5 111 , and the fourth contact end of the switch 1-5 108 is connected to the fourth contact end of the switch 2-5 111 .

The first contact end of the switch 1-6 109 is connected to the first contact end of the switch 2-6 112, the second contact end of the switch 1-6 109 is connected to the second contact end of the switch 2-6 112, The third contact end of the switch 1-6 109 is connected to the third contact end of the switch 2-6 112 , and the fourth contact end of the switch 1-6 109 is connected to the fourth contact end of the switch 2-6 112 .

The first contact end, the second contact end, the third contact end and the fourth contact end of the switch 1-4 107 constitute the first group of output current sources of the switching expansion device 100 and are connected to the electrical protection device. The first contact end, the second contact end, the third contact end and the fourth contact end of the switch 1-5 108 constitute the second group of output current sources of the switching expansion device 100 to be connected to the electrical protection device. The first contact end, the second contact end, the third contact end and the fourth contact end of the switches 1-6 109 form a third group of output current sources of the switching expansion device 100 to be connected to the electrical protection device.

The specific usage of the method for automatic line change between the relay protection device 400 and the tester of the present invention is listed below in several cases.

Case 1. The relay protection device 400 needs three sets of current tests, but the relay protection tester 300 actually only has two sets of current outputs.

The specific operation method is: connect the three groups of currents of the relay protection device 400 to the first group of output current sources, the second group of output current sources and the third group of output current sources, and close the switches 1-1 101, switches 1-2 103. All contacts of switches 1-4 107 can output the first group of output current sources of relay protection device 400 through current source 1; close switch 1-1101, switch 1-2 103, switch 1-5 108 All the contacts of the relay protection device 400 can be output through the current source 1; all the contacts of the switch 1-1 101, the switch 1-2 103, and the switch 1-6 109 can be closed The third output current source of the relay protection device 400 is output through the current source 1 ; similarly, the current output can also be performed through the current source 2 .

Situation 2. The three groups of currents of the relay protection device 400 need to verify the fixed value error when the current setting value is 50A, and the maximum output of a single group of current of the relay protection tester 300 is 32A.

The specific operation method is: all contacts of switch 1-1 101, switch 1-2 103, switch 1-4 107, switch 2-1 102, switch 2-2 105, switch 2-4 110 are passed through two sets of current sources Parallel output outputs the first group of output current sources of the relay protection device 400; close switch 1-1 101, switch 1-2 103, switch 1-5 108, switch 2-1 102, switch 2-2 105, switch All contacts of 2-5 111 output the second group of output current sources of the relay protection device 400 through two sets of current sources in parallel; close switch 1-1 101, switch 1-2 103, switch 1-6 109, All the contacts of the switch 2-1 102, the switch 2-2 105, and the switch 2-6 112 output to the third output current source of the relay protection device 400 through two sets of current sources connected in parallel.

Case 3: The relay protection device 400 needs to verify the fixed value error when the current setting value is 100A for the three groups of currents, and the relay protection tester 300 can output a maximum current of 32A for a single group.

The specific operation method is: close all contacts of switch 1-1 101, switch 1-2 103, switch 1-3 104, switch 2-1 102, switch 2-2 105, switch 2-3 106, close switch 1- 4. The first contact and the fourth contact of 107 can output the current of phase A 100A through the first group of output current sources.

Close all contacts of switch 1-1 101, switch 1-2 103, switch 1-3 104, switch 2-1 102, switch 2-2 105, switch 2-3 106, close the second contact of switch 1-4 107 contact and the fourth contact, the current of B-phase 100A can be output through the first set of output current sources.

Close all contacts of switch 1-1 101, switch 1-2 103, switch 1-3 104, switch 2-1 102, switch 2-2 105, switch 2-3 106, close the third contact of switch 1-4 107 contacts and the fourth contact, the current of C-phase 100A can be output through the first group of output current sources. The control of the output of the second group of output current sources or the output of the third group of output current sources is basically the same as that of the first group of output current sources, and will not be repeated here.

The switching expansion device 100 is also provided with a microcontroller and a control loop for controlling the input switch group, the intermediate switch group and the output switch group, and the microcontroller communicates with the background computer 200 through a serial port , the microcontroller and the control loop are controlled by DO. The model of the relay protection tester 300 of the present invention is OMICRONCMC356.

The switching expansion device 100 of the present invention uses the Modbus protocol to receive the control commands sent by the background computer 200 through serial port communication, and controls the control loop through its own opening, thereby realizing the on-off control of the switch.

It should be noted that the micro-controller and control loop have been widely used, and can only realize the output control of the input switch group, intermediate switch group and output switch group of the present invention, which can be used as the micro-controller and control circuit of the present invention. Loop, specific model selection, this embodiment provides a control loop structure for reference, as shown in Figure 3, in this control loop, the relay is controlled after the left input terminal of the resistor R3 receives a signal. Of course, those skilled in the art can choose according to the actual situation, and the microcontroller and the control loop are not the main inventive points of the present invention, and will not be repeated here.

The method for realizing the automatic line change between the relay protection device 400 and the tester does not need to change the line during the test, thereby reducing the workload and avoiding errors in line change, and providing conditions for fully automatic testing.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that Modifications or equivalent replacements are made to the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention.

Claims (10)

1. An automatic line change method between a relay protection device and a relay protection tester, characterized in that, it is provided with: A switching expansion device, which is used to expand at least two sets of input power sources of the relay protection tester into at least three sets of output current sources, and deliver the output current sources to the relay protection device; The background computer is used to control the switching expansion device and the relay protection tester. 2. The automatic line change method between the relay protection device and the relay protection tester according to claim 1, characterized in that: the switch extension device is provided with an input switch group, an intermediate switch group and an output switch group, The input switch group is connected to a relay protection tester, the input switch group and the output switch group are respectively connected to the intermediate switch group, and the input switch group is connected to a relay protection device. 3. The automatic line change method between the relay protection device and the relay protection tester according to claim 2, characterized in that: the input switch group is provided with a switch 1-1 and a switch 2-1, The middle switch group is provided with a switch 1-2, a switch 1-3, a switch 2-2 and a switch 2-3; The input switch group is provided with a switch 1-4, a switch 1-5, a switch 1-6, a switch 2-4, a switch 2-5 and a switch 2-6; The A terminal, B terminal, C terminal and H terminal of the switch 1-1 are respectively connected to one of the input current sources of the relay protection tester, and the A terminal, B terminal, C terminal and H terminal of the switch 2-1 are respectively connected to the Another set of input current source connections for the relay protection tester, The first contact end of the switch 1-1 and the A end of the switch 1-2 and the A end of the switch 1-3, the second contact end of the switch 1-1 and the B end of the switch 1-2 and the switch 1-3 The B terminal of the switch 1-1, the third contact terminal of the switch 1-1 and the C terminal of the switch 1-2 and the A terminal of the switch 2-3, the fourth contact terminal of the switch 1-1 and the H terminal of the switch 1-2 and Terminal B of switch 2-3, The first contact end of switch 2-1 and the A end of switch 2-2 and the C end of switch 1-3, the second contact end of switch 2-1 and the B end of switch 2-2 and switch 1-3 The H end of the switch 2-1, the third contact end of the switch 2-1 and the C end of the switch 2-2 and the C end of the switch 2-3, the fourth contact end of the switch 2-1 and the H end of the switch 2-2 and H terminal of switch 2-3, The first contact end of the switch 1-2 is connected with the first contact end of the switch 1-2, the A end of the switch 1-4, the A end of the switch 1-5 and the A end of the switch 1-6, and the switch 1- The second contact end of 2 is connected with the second contact end of switch 1-2, the B end of switch 1-4, the B end of switch 1-5 and the B end of switch 1-6, and the second contact end of switch 1-2 The three contact terminals are connected with the third contact terminal of switch 1-2, the C terminal of switch 1-4, the C terminal of switch 1-5 and the C terminal of switch 1-6, and the fourth contact of switch 1-2 terminal is connected with the first contact terminal of switch 2-3, the H terminal of switch 1-4, the H terminal of switch 1-5 and the H terminal of switch 1-6, The first contact end, the second contact end, the third contact end and the fourth contact end of the switch 1-2 are connected in parallel, and the first contact end, the second contact end, and the third contact end of the switch 2-3 are connected in parallel. The point terminal and the fourth contact terminal are connected in parallel, The first contact end of the switch 2-2 is connected with the A end of the switch 2-4, the A end of the switch 2-5, and the A end of the switch 2-6, and the second contact end of the switch 2-2 is connected with the switch 2- The B terminal of 4, the B terminal of switch 2-5, and the B terminal of switch 2-6 are connected, and the third contact terminal of switch 2-2 is connected with the C terminal of switch 2-4, the C terminal of switch 2-5, and the switch The C terminal of 2-6 is connected, the fourth contact terminal of switch 2-2 is connected with the H terminal of switch 2-4, the H terminal of switch 2-5, and the H terminal of switch 2-6, The first contact end of the switch 1-4 is connected with the first contact end of the switch 2-4, the second contact end of the switch 1-4 is connected with the second contact end of the switch 2-4, and the switch 1-4 The third contact end of the switch is connected with the third contact end of the switch 2-4, the fourth contact end of the switch 1-4 is connected with the fourth contact end of the switch 2-4, The first contact end of switch 1-5 is connected with the first contact end of switch 2-5, the second contact end of switch 1-5 is connected with the second contact end of switch 2-5, switch 1-5 The third contact end of the switch is connected with the third contact end of the switch 2-5, the fourth contact end of the switch 1-5 is connected with the fourth contact end of the switch 2-5, The first contact end of switch 1-6 is connected with the first contact end of switch 2-6, the second contact end of switch 1-6 is connected with the second contact end of switch 2-6, switch 1-6 The third contact end of the switch is connected with the third contact end of the switch 2-6, and the fourth contact end of the switch 1-6 is connected with the fourth contact end of the switch 2-6; The first contact end, the second contact end, the third contact end and the fourth contact end of the switches 1-4 constitute the first group of output current sources of the switching expansion device and are connected to the electrical protection device; The first contact end, the second contact end, the third contact end and the fourth contact end of the switches 1-5 constitute the second group of output current sources of the switching expansion device and are connected to the electric protection device; The first contact end, the second contact end, the third contact end and the fourth contact end of the switches 1-6 constitute the third group of output current sources of the switching expansion device and are connected to the electric protection device. 4. The automatic line change method between the relay protection device and the relay protection tester according to any one of claims 1 to 3, characterized in that: the background computer and the relay protection tester are connected through a network port to communicate. 5. The automatic line change method between the relay protection device and the relay protection tester according to any one of claims 1 to 3, characterized in that: the switching extension device and the relay protection tester pass the test Wire connection, so that the current output by the relay protection tester is connected to the switching expansion device, and at the same time, the extended current interface is connected to the relay protection device. 6. The automatic line change method between the relay protection device and the relay protection tester according to any one of claims 1 to 3, characterized in that: the connection between the background computer and the switching expansion device is performed through a serial port communication. 7. The automatic line change method between the relay protection device and the relay protection tester according to any one of claims 1 to 3, characterized in that: the connection between the background computer and the relay protection device is performed through the network port Communication, so as to receive the test information of the relay protection device. 8. The automatic line change method between the relay protection device and the relay protection tester according to any one of claims 1 to 3, characterized in that: the background computer uses the Modbus protocol to control the switching expansion device . 9. The method for automatic line change between the relay protection device and the relay protection tester according to claim 2, characterized in that: the switching expansion device is also provided with a microcontroller and is used to control the input switch group, the control loop of the intermediate switch group and the output switch group, the microcontroller communicates with the background computer through a serial port, and the microcontroller and the control loop are controlled by DO. 10. The automatic line change method between the relay protection device and the relay protection tester according to claim 3, characterized in that: the model of the relay protection tester is OMICRON CMC356; Switch 1-1, Switch 2-1, Switch 1-2, Switch 1-3, Switch 2-2 and Switch 2-3, Switch 1-4, Switch 1-5, Switch 1-6, Switch 2-4, Both switches 2-5 and switches 2-6 are four-contact switches.

Images