Relay protection control system of high-voltage switch cabinet

Abstract

The utility model discloses a relay protection control system of a high-voltage switch cabinet, which comprises the high-voltage switch cabinet, a relay protection device connected with a PLC (Programmable Logic Controller) is arranged in the high-voltage switch cabinet, a transformer is connected with the high-voltage switch cabinet, a plurality of thyristor power regulators are arranged, the plurality of thyristor power regulators are connected with the transformer, and the PLC is connected with the transformer. According to the utility model, relay protection parameters are modified in a communication mode through a PLC communication protocol technology, after undisturbed switching of a plurality of high-power loads is realized, fixed value synchronous switching is realized, and the high-power loads are connected with the thyristor power regulators in a one-to-one correspondence manner. Therefore, the high-power load is always under one-to-one protection of the relay protection device, relay protection with different fixed values is provided for different loads, the device is mainly applied to occasions where power is supplied to multiple high-power loads, and only one load can be supplied with power and provided with relay protection at the same time.

Description

Technical Field

[0001] The utility model belongs to the technical field of high - voltage switchgear power distribution, and particularly relates to a relay protection control system for a high - voltage switchgear. Background Technique

[0002] Relay protection technology mainly consists of power grid fault analysis, relay protection principle and implementation, relay protection device design, and relay protection operation and maintenance technology. The relay protection device is the core to complete the relay protection function, which can react to faults or abnormal operating states of electrical components in the power grid and act on the circuit breaker to trip or send out signals, which is an automatic device.

[0003] The main uses of the relay protection device are as follows: 1. Tripping: When a fault occurs in the protected transmission line or electrical component, the relay protection device quickly acts to trip the circuit breaker, cut off the faulty part from the power system, minimize the degree of damage, and ensure that the non - faulty part continues to operate normally; 2. Warning: When the protected transmission line or electrical component is in an abnormal operating state, the relay protection device sends out a signal to notify the operator to take corresponding measures.

[0004] The existing relay protection control system for high - voltage switchgear has the following problems:

[0005] (1). Adopting a one - to - one protection design, it is necessary to configure a set of relay protection devices for each high - power load, which greatly increases the comprehensive power distribution cost;

[0006] (2). When the startup frequency of high - power loads is relatively low, the power distribution equipment configured one - to - one will be idle for a long time, resulting in low utilization rate of the relay protection device;

[0007] Therefore, we propose a relay protection control system for a high - voltage switchgear. Content of the Utility Model

[0008] The purpose of the utility model is to provide a relay protection control system for a high - voltage switchgear to solve the problems raised in the above - mentioned background technique.

[0009] To achieve the above purpose, the utility model provides the following technical solution: A relay protection control system for a high - voltage switchgear, including:

[0010] A high - voltage switchgear, which is internally provided with a relay protection device connected to a PLC;

[0011] A transformer, which is connected to the high - voltage switchgear;

[0012] Thyristor power regulators, several thyristor power regulators are provided, and several thyristor power regulators are connected to the transformer;

[0013] High-power loads, several high-power loads are provided, and several said high-power loads are connected to several said thyristor power regulators in one-to-one correspondence.

[0014] Preferably, the relay protection device is provided with a 485 communication interface, the communication interface of the PLC is connected to the 485 communication interface on the relay protection device, and a set of independent relay protection setting values is assigned to each high-power load through the PLC.

[0015] Preferably, the PLC is a Siemens Smart200 PLC.

[0016] Preferably, the capacity of the transformer is 1.25 times the maximum power load of the high-power load.

[0017] Preferably, the high-power load is a load with a power greater than 1 MW.

[0018] Preferably, the relay protection control system selects the high-power load through the PLC. At any time, only one high-power load is selected and in the working state.

[0019] Compared with the prior art, the beneficial effects of the present utility model are:

[0020] The present utility model realizes the synchronous switching of setting values after the disturbance-free switching of multiple high-power loads by configuring a high-voltage switch cabinet 1 with a relay protection device connected to the PLC and modifying the relay protection parameters in a communication form through the PLC communication protocol technology, so that the high-power load is always under the one-to-one protection of the relay protection device, and realizes relay protection with different setting values for different loads. It is mainly applied to the occasions of supplying power to multiple high-power loads, and at the same time, only one load can be powered and provided with relay protection;

[0021] For multiple high-power loads, only one high-voltage switch cabinet and one transformer need to be configured to achieve one-to-one relay protection, saving the power supply cost;

[0022] Using the PLC to select and switch the load, at any time, only one device is selected and in the working state, which not only ensures that the transformer will not be overloaded but also improves the utilization rate of the relay protection device;

[0023] The PLC adjusts the corresponding protection parameters of the comprehensive protection according to different loads in a communication form, which not only continues the original intention of the one-to-one protection of the relay protection device but also expands the protection ability of the relay protection device. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the system structure of the present utility model;

[0025] Figure 2 Schematic diagram of the PLC communication control program of the present utility model.

[0026] In the figure: 1, high-voltage switchgear; 2, transformer; 3, thyristor power regulator; 4, high-power load. Specific embodiments

[0027] The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0028] Please refer to Figure 1 , the relay protection control system of the high-voltage switchgear provided by the present utility model. The relay protection control system switches and selects the high-power load 4 through the PLC. At any time, only one high-power load 4 is selected and in the working state, including:

[0029] High-voltage switchgear 1, the high-voltage switchgear 1 is internally provided with a relay protection device connected to the PLC. The relay protection device is provided with a 485 communication interface. The communication interface of the PLC is connected to the 485 communication interface on the relay protection device. A set of independent relay protection setting values is allocated to each high-power load 4 through the PLC. The power supply protection of the transformer 2 and the high-power load 4 is realized by setting the relay protection setting values. The PLC is a Siemens Smart200 PLC;

[0030] Transformer 2, the transformer 2 is connected to the high-voltage switchgear 1, and the capacity of the transformer 2 is 1.25 times the maximum power load of the high-power load 4;

[0031] Thyristor power regulator 3, there are several thyristor power regulators 3, and several thyristor power regulators 3 are connected to the transformer 2. The power supply and distribution of the high-power load 4 and the regulation of the load output power are realized by controlling the conduction of the thyristor power regulator 3;

[0032] High-power load 4, there are several high-power loads 4, and several high-power loads 4 are connected to several thyristor power regulators 3 in one-to-one correspondence. The high-power load 4 is a load with a power greater than 1 MW.

[0033] The utility model realizes the synchronous switching of setting values after the non-disturbing switching of multiple high-power loads through a high-voltage switch cabinet 1 with a relay protection device connected to a PLC built therein. By means of PLC communication protocol technology, the relay protection parameters are modified in a communication manner, so that the high-power loads are always under the one-to-one protection of the relay protection device, and the relay protection providing different setting values for different loads is realized. It is mainly applied to the occasions of supplying power to multiple high-power loads, and at the same time, only one load can be powered and relay protection can be provided;

[0034] For multiple high-power loads, only one high-voltage switch cabinet and one transformer need to be configured to realize one-to-one relay protection, saving the power supply cost;

[0035] The PLC is used to select and switch the load. At any time, only one device is selected and in the working state, which not only ensures that the transformer will not be overloaded, but also improves the utilization rate of the relay protection device;

[0036] The PLC adjusts the corresponding protection parameters of the comprehensive protection in a communication manner, which not only continues the original intention of the one-to-one protection of the relay protection device, but also expands the protection ability of the relay protection device.

[0037] This embodiment is the specific application of the relay protection control system of the high-voltage switch cabinet:

[0038] Taking three groups of high-power loads of 1MW, 2MW, and 4MW as an example, the incoming line voltage of the transformer is 6kV, the capacity is 5000kVA, the relay protection device selects the Xuji WGB-631A microcomputer auxiliary transformer protection device, and the PLC selects the SR20 of the Siemens Smart200 series;

[0039] Connect the communication interface of the PLC to the 485 of the relay protection device;

[0040] According to the power of the high-power load, calculate the corresponding relay protection setting value;

[0041] Consult the operation manual of the Xuji comprehensive protection to understand the read-write address of its setting value area;

[0042] Then program the PLC, and use the program to modify the data in the setting value area of the Xuji comprehensive protection. As Figure 2 shown, use the PLC communication control program to modify the data in the setting value area of the Xuji comprehensive protection;

[0043] Connect all the power cables, turn on the control power supply, and perform the high-power load selection operation on the touch screen or the upper computer. After the load is selected, the upper computer sends the selected result to the PLC, and the PLC executes a write data operation to write a set of parameters corresponding to the selected load into the relay protection setting value area;

[0044] Perform relay protection tests on the selected loads in turn, and issue test reports according to the test results.

[0045] Although the embodiments of the present utility model have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present utility model, and the scope of the present utility model is defined by the appended claims and their equivalents.

Claims

1. A relay protection control system for a high-voltage switchgear, characterized in that, Including: A high-voltage switchgear cabinet (1), and a relay protection device connected to a PLC is built in the high-voltage switchgear cabinet (1); A transformer (2), and the transformer (2) is connected to the high-voltage switchgear cabinet (1); A thyristor power regulator (3), several thyristor power regulators (3) are provided, and the several thyristor power regulators (3) are connected to the transformer (2); High-power loads (4), several high-power loads (4) are provided, and the several high-power loads (4) and the several thyristor power regulators (3) are connected in one-to-one correspondence.

2. The relay protection control system of a high-voltage switchgear according to claim 1, characterized in that: The relay protection device is provided with a 485 communication interface, the communication interface of the PLC is connected to the 485 communication interface on the relay protection device, and a set of independent relay protection setting values is allocated to each high-power load (4) through the PLC.

3. The relay protection control system of a high-voltage switchgear according to claim 2, characterized in that: The PLC is a Siemens Smart200 PLC.

4. A relay protection control system for a high-voltage switch cabinet according to claim 1, characterized in that: The capacity of the transformer (2) is 1.25 times the maximum power load of the high-power load (4).

5. The relay protection control system of a high-voltage switchgear according to claim 4, characterized in that: The high-power load (4) is a load with a power greater than 1 MW.

6. The relay protection control system of a high-voltage switchgear according to claim 3, characterized in that: The relay protection control system selects the high-power load (4) through the PLC, and at any time, only one high-power load (4) is selected and in the working state.

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