Method for transforming 500kV intelligent station protection device in 3 / 2 wiring form

Abstract

The invention provides a transformation method for a 500kV intelligent station protection device in a 3 / 2 wiring form. The transformation method comprises the following steps: Step 1, II bus-bus power-off protection transformation; 2, N independent strings are arranged, and power failure protection transformation is carried out on the first string; 3, power failure protection transformation is conducted on the second string to the Nth string according to the method in the step 2, and after transformation of all the strings is completed, the II bus is put into operation; and step 4, performing power-off protection transformation on the bus of the I bus. By reasonably planning the power failure sequence of the equipment and transforming the protection device according to the power failure plan, power failure of the whole station is not needed, safe and stable operation of the whole power system is guaranteed, and stable power supply is guaranteed; the bus does not need to be powered off repeatedly, bus protection does not need to be updated repeatedly, safety risks are reduced, and stable operation of the system is guaranteed; the problems of new and old cooperation transition between bus protection and side circuit breaker protection and between a side circuit breaker merging unit and an intelligent terminal are solved, and safety and reliability of an operation interval are guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of power grid upgrading and reconstruction, and in particular to a reconstruction method of a 500kV intelligent station protection device in a two-thirds wiring form. Background Art

[0002] The current 500kV smart substation with 3 / 2 wiring generally uses a current merging unit as a current receiving and transmitting device, and uses an intelligent terminal as a device for receiving the tripping signal of the protection device and outputting the tripping. The busbar protection receives the current SV information from the current merging unit of the side circuit breaker. When the protection is activated, it sends a tripping GOOSE command to the side circuit breaker intelligent terminal, and at the same time sends a start failure GOOSE signal to the side circuit breaker protection. When the side circuit breaker fails, its circuit breaker protection device sends a failure start bus action GOOSE signal to the busbar protection device. In the 500kV smart substation with 3 / 2 wiring that was put into operation early, the operating life of the protection equipment is close to the maximum life required by the industry standard, and equipment transformation is required. For those that cannot be transformed by shutting down the entire station as a whole, it involves the transition of the new and old coordination between the busbar protection and the side circuit breaker protection, the side circuit breaker merging unit and the intelligent terminal.

[0003] The existing transformation methods are as follows: Method 1: When carrying out protection transformation on a 500kV smart substation with 3 / 2 connection, first shut down the entire station, then carry out protection transformation, and put the entire station into operation after all the transformations are completed.

[0004] Method 2: When performing protection transformation on a 500kV smart substation with 3 / 2 connection, shut down each string for protection transformation, and finally perform busbar protection transformation. For example, if there are three independent strings in a 500kV smart substation with 3 / 2 connection, namely string 1, string 2, and string 3, shut down string 1 first. There are two busbars, namely bus I and bus II. The transformation steps are as follows: 1) Stop the first string; 2) Modify all protection devices on the first string, including circuit breaker protection, incoming short lead protection, incoming line protection, outgoing short lead protection, and outgoing line protection; 3) Stop busbar I (or II), update busbar protection configuration, and put the busbar into operation after completion; 4) Stop bus II (or I), update bus protection configuration, and put the bus into operation after completion; 5) Put the first string into operation; 6) Repeat the above steps to transform the second and third strings respectively; 7) Stop busbar I (or II), transform busbar protection, and put the busbar into operation after completion; 8) Stop bus II (or I) and transform the bus protection. After completion, put the bus into operation.

[0005] The above-mentioned transformation method 1 requires a station-wide power outage before the transformation, which is not conducive to the stable operation of the entire power system, and reduces the power transmission time, reducing the efficiency of the plant; the transformation method 2 uses the method of power outage transformation string by string. After each string transformation is completed, the bus needs to be stopped and the bus protection configuration updated. The transformation method is complicated, the steps are cumbersome, the safety risk is high, and it is not conducive to the stable operation of the system. Summary of the invention

[0006] The present invention provides a method for transforming a protection device of a 500kV intelligent station in a 2 / 3 wiring form, and proposes an effective whole-station protection transformation method for a 500kV intelligent station in a 3 / 2 wiring form that cannot be transformed by a whole-station power outage, thereby reducing safety risks.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is: A method for modifying a protection device of a 500kV intelligent station in a 3 / 2 wiring form, wherein the intelligent station in the 3 / 2 wiring form comprises two busbars, namely, busbar I and busbar II, wherein a plurality of independent strings are arranged between busbar I and busbar II, wherein three circuit breakers, namely, circuit breaker 1DL, circuit breaker 2DL and circuit breaker 3DL, are arranged on each string, wherein circuit breaker 1DL is connected to one side of busbar II, circuit breaker 1DL is connected to one side of busbar I, an incoming line of each string is connected between circuit breakers 1DL and 2DL, and an outgoing line of each string is connected between circuit breakers 2DL and 3DL, and the modification method comprises: Step 1, II busbar power failure protection transformation; all incoming and outgoing lines and I busbar are running, II busbar is powered off, and all 3DL circuit breakers in series are disconnected; Step 2, suppose there are N independent strings in total, and modify the power failure protection of the first string; the second, third, ... N strings and I bus are in operation, and the entire first string is powered off; after the power failure protection modification of the first string is completed, close the 2DL and 3DL circuit breakers of the first string, and the incoming and outgoing lines of the first string are put into operation; Step 3, perform power outage protection transformation on the 2nd to Nth strings according to the method in Step 2, until all strings are transformed, and then put II bus into operation; suppose the nth string is transformed, then the 1st, ...n-1, n+1, ...Nth strings and I bus are in operation, and the entire nth string is out of power; after the power outage protection transformation of the nth string is completed, close the 2DL and 3DL circuit breakers of the nth string, and put the incoming and outgoing lines of the nth string into operation; Step 4, power outage protection transformation of busbar I; all incoming and outgoing lines and busbar II are in operation, and busbar I is out of power.

[0008] The specific steps of Step 1 above are: Step 1.1, stop all 3DL circuit breakers of II mother, and all incoming and outgoing lines are running; Step 1.2, disable II busbar protection and all 3DL circuit breaker protections; Step 1.3, transform all 3DL merging units and intelligent terminals of II mother; Step 1.4, transform the II busbar merging unit and busbar intelligent terminal; Step 1.5, modify all 3DL circuit breaker protections of II mother; Step 1.6, modify the II busbar protection.

[0009] The specific steps of Step 2 above are: Step 2.1. Stop all circuit breakers in the first string interval; Step 2.2, disable the 2DL circuit breaker protection, 1DL circuit breaker protection, incoming line short lead protection, outgoing line short lead protection, outgoing line protection, and incoming line protection of the first string; Step 2.3, transform the 2DL and 1DL circuit breaker merging units and intelligent terminals of the first string; Step 2.4, modify the 2DL and 1DL circuit breaker protection, incoming short lead protection and outgoing short lead protection of the first string; Step 2.5, modify the first string incoming line protection and outgoing line protection; Step 2.6, after the first string is completely transformed, close the 2DL and 3DL circuit breakers of the first string; Step 2.7, put 1 string of incoming wires and 1 string of outgoing wires into operation.

[0010] The specific steps of Step 4 above are: Step 4.1. Stop all 1DL circuit breakers of I mother, and all incoming and outgoing lines operate normally; Step 4.2, disable I busbar protection; Step 4.3, transform the I busbar merging unit and the intelligent terminal; Step 4.4, modify the I busbar protection.

[0011] The number of the above-mentioned independent strings is 3.

[0012] The present invention provides a method for transforming a 500kV intelligent station protection device in a two-thirds wiring form, which has the following beneficial effects: 1. No need to shut down the entire station to ensure the safe and stable operation of the entire power system and the stable supply of electricity.

[0013] 2. The busbar does not need to be repeatedly powered off, and the busbar protection does not need to be repeatedly updated, which reduces safety risks and ensures stable operation of the system.

[0014] 3. Solve the problem of transition between busbar protection and side circuit breaker protection, side circuit breaker merging unit and smart terminal, and ensure the safety and reliability of the operating interval. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will be further described below in conjunction with the accompanying drawings and embodiments: Figure 1 This is a load diagram of the modified Step 1 of the present invention; Figure 2 The load diagram of the present invention is modified in Step 2 Figure 1 ; Figure 3 The load diagram of the present invention is modified in Step 2 Figure 2 ; Figure 4 This is a load diagram of the modified Step 4 of the present invention. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solutions and advantages of the present invention clearer, the following content will systematically and completely describe the specific technical solutions of the present invention in combination with the drawings provided according to the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0017] Example: A method for transforming a 500kV intelligent station protection device in a two-thirds wiring form, comprising: Step 1: 500kV II busbar power outage protection transformation; all incoming and outgoing lines and I busbar are in operation, II busbar is out of power: 1. Stop all 3DL circuit breakers of 500kV II bus, all incoming and outgoing lines are operating normally, see the attached load diagram Figure 1 ; 2. Disable II busbar protection and all 3DL circuit breaker protections; 3. Reconstruct all 3DL merging units and intelligent terminals of II mother; 4. Reconstruct the II busbar merging unit and busbar intelligent terminal; 5. Modify the protection of all 3DL circuit breakers in II mother; 6. Modify the 500kV II busbar protection.

[0018] Step 2: Power failure protection modification of the first string; the second, third and I mother strings are in operation, and the first string is completely powered off: 1. Stop all circuit breakers in the first series bay. See the attached load diagram. Figure 2 ; 2. Disable the 2DL circuit breaker protection, 1DL circuit breaker protection, incoming line short lead protection, outgoing line short lead protection, outgoing line protection, and incoming line protection of the first string; 3. Reconstruct the 2DL and 1DL circuit breaker merging units and intelligent terminals of the first string; 4. Modify the 2DL and 1DL circuit breaker protection, incoming short lead protection and outgoing short lead protection of the first string; 5. Reconstruct the first string of incoming line protection and outgoing line protection; 6. After all modifications to the first string are completed, close the 2DL and 3DL circuit breakers of the first string; 7. Put one incoming line and one outgoing line into operation (see the attached load diagram). Figure 3 ).

[0019] Step 3: The power outage protection transformation of other strings is similar to step 2. After the transformation of strings 1 to 3 is completed, put mother II into operation.

[0020] Step 4: 500kV I busbar power outage protection transformation; all incoming and outgoing lines and II busbar are running, I busbar is powered off: 1. Stop all 1DL circuit breakers of 500kV I busbar, and all incoming and outgoing lines are operating normally. See the attached load diagram. Figure 4 ; 2. Disable busbar protection of I; 3. Transform the 500kV I busbar merging unit and intelligent terminal; 4. Modify the 500kV I busbar protection.

Claims

1. A method for transforming a 500kV intelligent station protection device in a 3 / 2 wiring form, wherein the intelligent station in the 3 / 2 wiring form comprises two busbars, namely, busbar I and busbar II, wherein a plurality of independent strings are arranged between busbar I and busbar II, wherein each string is provided with three circuit breakers, namely, circuit breaker 1DL, circuit breaker 2DL and circuit breaker 3DL, circuit breaker 1DL is connected to one side of busbar II, and circuit breaker 1DL is connected to one side of busbar I, wherein the incoming line of each string is connected between circuit breakers 1DL and 2DL, and the outgoing line of each string is connected between circuit breakers 2DL and 3DL, wherein: The transformation methods include: Step 1, II busbar power failure protection transformation; all incoming and outgoing lines and I busbar are running, II busbar is powered off, and all 3DL circuit breakers in series are disconnected; Step 2, suppose there are N independent strings in total, and modify the power failure protection of the first string; the second, third, ... N strings and I bus are in operation, and the entire first string is powered off; after the power failure protection modification of the first string is completed, close the 2DL and 3DL circuit breakers of the first string, and the incoming and outgoing lines of the first string are put into operation; Step 3, perform power outage protection transformation on the 2nd to Nth strings according to the method in Step 2, until all strings are transformed, and then put II bus into operation; suppose the nth string is transformed, then the 1st, ...n-1, n+1, ...Nth strings and I bus are in operation, and the entire nth string is out of power; after the power outage protection transformation of the nth string is completed, close the 2DL and 3DL circuit breakers of the nth string, and put the incoming and outgoing lines of the nth string into operation; Step 4, power outage protection transformation of busbar I; all incoming and outgoing lines and busbar II are in operation, and busbar I is out of power.

2. A method for transforming a 500kV intelligent station protection device in a two-thirds wiring form according to claim 1, characterized in that: The specific steps of Step 1 are: Step 1.1, stop all 3DL circuit breakers of II mother, and all incoming and outgoing lines are running; Step 1.2, disable II busbar protection and all 3DL circuit breaker protections; Step 1.3, transform all 3DL merging units and intelligent terminals of II mother; Step 1.4, transform the II busbar merging unit and busbar intelligent terminal; Step 1.5, modify all 3DL circuit breaker protections of II mother; Step 1.6, modify the II busbar protection.

3. A method for transforming a 500kV intelligent station protection device in a two-thirds wiring form according to claim 2, characterized in that: The specific steps of Step 2 are: Step 2.

1. Stop all circuit breakers in the first string interval; Step 2.2, disable the 2DL circuit breaker protection, 1DL circuit breaker protection, incoming line short lead protection, outgoing line short lead protection, outgoing line protection, and incoming line protection of the first string; Step 2.3, transform the 2DL and 1DL circuit breaker merging units and intelligent terminals of the first string; Step 2.4, modify the 2DL and 1DL circuit breaker protection, incoming short lead protection and outgoing short lead protection of the first string; Step 2.5, modify the first string incoming line protection and outgoing line protection; Step 2.6, after the first string is completely transformed, close the 2DL and 3DL circuit breakers of the first string; Step 2.7, put 1 string of incoming wires and 1 string of outgoing wires into operation.

4. A method for transforming a 500kV intelligent station protection device in a two-thirds wiring form according to claim 3, characterized in that: The specific steps of Step 4 are: Step 4.

1. Stop all 1DL circuit breakers of I mother, and all incoming and outgoing lines operate normally; Step 4.2, disable I busbar protection; Step 4.3, transform the I busbar merging unit and the intelligent terminal; Step 4.4, modify the I busbar protection.

5. A method for transforming a 500kV intelligent station protection device in a two-thirds wiring form according to claim 1, characterized in that: The number of the independent strings is 3.

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