Rapid switching method and device for power system of petrochemical enterprise

Abstract

The invention relates to a rapid switching method and device for a power system of a petrochemical enterprise. The method comprises the following steps: (1) collecting a signal; (2) converting the signal; (3) judging whether a jumper-incoming switch command is sent out or not according to the collected or converted digital signal and the preset starting condition; (4) after an incoming switch is tripped off, judging whether a switching command is sent out or not according to a preset switching condition; and (5) after receiving the jumper-incoming switch command, executing an operation of tripping off the incoming switch, and after receiving the switching command, executing an operation of closing an emergency power supply. According to the rapid switching method and device provided by the invention, the faulty condition of a working power supply can be keenly perceived and is quickly cut off; and the best time of inputting the emergency power supply is judged to carry out the operation of switching into the emergency power supply. An experiment proves that the problems of production halts, production reduction and the like caused by system power fluctuations can be avoided; and smooth transition of large-scale electrical equipment of a generator, a large synchronous machine and the like in the petrochemical enterprise can be achieved in the switching process.

Description

technical field [0001] The invention relates to a fast switching method and device for 110kV power systems of petrochemical enterprises. Background technique [0002] figure 1 It is a schematic diagram of the 6KV bus residual voltage characteristics of a 300MW unit, V D is the residual voltage of the busbar, the arc ABCD indicates the phasor change trajectory of the residual voltage of the busbar, and △U is the differential pressure between the backup power supply voltage and the residual voltage of the busbar. [0003] For the convenience of analysis, we take a power system and a single motor as an example, fully simplify the equivalent circuit of the backup power system and the motor according to the transient analysis model, ignore the winding resistance, excitation impedance, etc., and use the equivalent potential V S and equivalent reactance X S Represents the backup power system, with the equivalent potential V M and equivalent reactance X M to represent the motor...

AI Technical Summary

Problems solved by technology

General plant electrical equipment forms a passive network after the working power supply trips, while petrochemical enterprises form a passive network after the working power supply image 3 After the incoming line 1 trips, since the generator and other equipment are connected to the busbar I, they form an active network. If the power system of the petrochemical enterprise simply applies the fast switching device It cannot guarantee the safety of the above generators, synchronous motors and other large electrical equipment

In addition, there are many large-capacity fans, compressors and other equipment inside the petrochemical system. These devices are loads with large moment of inertia. There is a large difference in the attenuation speed, and these differences must also determine that the fast switching device for the backup power supply of petrochemical enterprises cannot be simply applied to the fast switching device currently only used in general factories.

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