Hydropower station black-start system and method with double-voltage-level wiring

Abstract

The invention discloses a hydropower station black-start system and method with double-voltage-level wiring. The hydropower station black-start system comprises a first hydro-generator, a three-winding main transformer, a first 500kV circuit breaker, a second 220kV circuit breaker, a first 220kV line, a 500kV circuit breaker, a second 500kV line, a fourth 500kV circuit breaker, a third 500kV line,a high-voltage station transformer and a 10kV station incoming line switch. All switches and knife switches on a black start path are closed, only the circuit breaker for supplying power to a circuitis kept in an off state, a guide vane starting unit is opened by utilizing self energy storage of a hydro-generator, and when the hydro-generator is at a constant speed to a rated rotating speed, anexcitation system control mode is switched into an automatic mode, the hydro-generator with the three-winding main transformer is enabled to build voltage to rated voltage, a working power supply of aplant system is recovered in time, first 220kV line power transmission, second 500kV line power transmission and third 500kV line power transmission are sequentially realized, the black-start capability of a power grid is improved, and the safety of a plant network in coping with extreme conditions is ensured.

Description

technical field [0001] The invention belongs to the technical field of hydropower black start, and in particular relates to a hydropower black start system and method for double voltage level wiring. Background technique [0002] With the change of the global environment, extreme natural disasters have occurred frequently in recent years, which has had a major impact on the normal life of human beings. As the most basic demand in the fields of industry, agriculture, and residential life, how to ensure stable, reliable, and safe electricity? Supply has always been the goal that electric power workers around the world strive for. From the perspective of the overall situation, the construction of the power grid is dedicated to building a strong power grid and formulating various assessment systems. The purpose is to reduce the probability of power outages. , Capable units should resume power transmission as soon as possible to reduce the pressure on the power grid. To this en...

AI Technical Summary

Problems solved by technology

The current known black start technology has the following problems: (1) The output line voltage level is single, usually one voltage level and one wiring structure, resulting in a small recovery range during black start, especially for large units, which weakens the black start. Power supply capacity; (2) The two units do not use expansion unit wiring. If the self-storage capacity of one unit is insufficient, the other unit cannot be quickly started in the case of startup failure, which prolongs the black start time. At the same time, the two units The unit cannot realize the fast standby conversion function; (3) The excitation is manually empty-charged when the black start is activated, resulting in the voltage automatically rising when the line is put into operation, which brings safety hazards to various electrical equipment

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