System overvoltage suppression device

Abstract

The invention discloses a system overvoltage suppression device and relates to the technical field of power system overvoltage absorption. The system overvoltage suppression device comprises a high-voltage current limiting fuse, a voltage transformer, a high-energy-capacity surge absorber, a high-voltage fuse, an intelligent resonance elimination switch and a microcomputer comprehensive protection device, wherein one end of the high-voltage current limiting fuse and one end of a high-speed fuse are respectively connected to a high-voltage isolator; the other end of the high-voltage current limiting fuse is connected to one end of a high-energy-capacity overvoltage protector; the other end of the high-energy-capacity overvoltage protector is connected to the ground; the other end of the high-speed fuse is connected to the voltage transformer; the voltage transformer is respectively connected to the intelligent resonance elimination switch and the microcomputer comprehensive protection device; the microcomputer comprehensive protection device is connected to the intelligent resonance elimination switch; and the intelligent resonance elimination switch is connected to the ground. The system overvoltage suppression device can replace a voltage transformer cabinet and prefects detection and measurement, protective capability and protected capability of the voltage transformer cabinet, the system peak overvoltage can be suppressed, and the residual voltage value is low and the resonance can be eliminated accurately and quickly.

Description

technical field [0001] The invention relates to the technical field of power system overvoltage absorption. Background technique [0002] For a long time, most of the 6~35KV power grids in my country's industrial and mining enterprises have adopted the neutral point ungrounded operation mode. Running in the power system, the more serious problems are short-circuit faults, ground faults and resonance faults. For short-circuit faults, the circuit breaker cuts off the faulty line. As long as the design is reasonable and the appropriate circuit breaker is selected, the range of short-circuit faults will not expand, but At the same time, we must also pay attention to the problem of operating overvoltage. Installing a system overvoltage suppression device or a large-capacity overvoltage protector can better protect the equipment from impact and prolong the service life of the equipment. Ground faults and resonance faults are very important for power systems. It is relatively simp...

AI Technical Summary

Problems solved by technology

Running in the power system, the more serious problems are short-circuit faults, ground faults and resonance faults. For short-circuit faults, the circuit breaker cuts off the faulty line. As long as the design is reasonable and the appropriate circuit breaker is selected, the range of short-circuit faults will not expand, but At the same time, we must also pay attention to the problem of operating overvoltage. Installing a system overvoltage suppression device or a large-capacity overvoltage protector can better protect the equipment from impact and prolong the service life of the equipment. Ground faults and resonance faults are very important for power systems. It is relatively simple to deal with, but if the method is not appropriate, and if there is no suitable system overvoltage protection device to suppress it, the fault will also develop and expand, causing serious consequences, such as overvoltage energy impact causing saturation of voltage transformers, and ferromagnetic resonance causing voltage The transformer is burst and damaged, and the insulation of the equipment is damaged due to overvoltage and its energy, etc.

[0003] For the neutral point indirect grounding system, my country's current electric power regulations allow operation with a single-phase ground fault for 2 hours, which refers to metallic grounding here. If it is arc grounding, it will cause serious harm. Single-phase ground fault is arc light Grounding will generate an arc overvoltage with a maximum value of more than 3.5 times the phase voltage in the system. If such a high overvoltage acts on the power grid for several hours, it will inevitably cause cumulative damage to the insulation in the electrical equipment. If the insulation of all phases is weak The link will cause insulation to ground breakdown, which will cause a major accident of phase-to-phase short circuit

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