Analytical method for phase commutation failure of DC inverter station caused by switching of AC filter

Abstract

The invention provides a method for analyzing DC inverter station phase change failure caused by AC filter switching. The method comprises the following steps of: S1, establishing a corresponding equivalent analog circuit according to a high-voltage DC transmission receiving end system structure; S2, calculating transient voltage of an AC bus according to the analog circuit established in the stepS1; and S3, calculating a phase change voltage time area / Sa / which can be provided by an AC system and a voltage time area / Scr / required in the phase change process, and comparing the / Sa / with the / Scr / to judge whether the phase change succeeds or not. According to the method, an HVDC system phase change failure mechanism caused by voltage reduction and distortion is analyzed by a harmonic voltage time area-based phase change failure analysis method through establishing an equivalent model.

Description

technical field [0001] The invention belongs to the technical field of power systems, and in particular relates to an analysis method for phase commutation failure of a DC inverter station caused by switching of an AC filter. Background technique [0002] Traditional high-voltage direct current transmission has large transmission capacity, good long-distance power transmission economy, strong controllability, and has the advantages of asynchronous networking. It is widely used in engineering. Due to the use of semi-controlled thyristor devices as commutation elements, the commutation process of HVDC power transmission depends on the power provided by the AC system, and all factors that cause voltage changes on the system side (such as distortion, zero point offset, etc.) may cause inversion Side commutation failed. Commutation failure will lead to a short circuit on the DC side of the inverter, causing the DC voltage to be zero, the DC current to increase, and the DC syste...

AI Technical Summary

Problems solved by technology

The switching of AC filters is frequent during the normal operation of the DC transmission system. When the timing of switching is inappropriate, the voltage distortion in the transient process is relatively large. Although AC filters are generally equipped with phase-selection closing devices, the timing However, due to the influence of uncertain factors (such as environment, temperature, etc.) in the action characteristics of the circuit breaker, it is difficult to really play a role in suppressing voltage distortion, and voltage distortion may cause commutation failure

However, in the prior art, the cause of commutation failure has not been analyzed from the mechanism

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