Large current source for running test of direct-current transmission converter valve and compensation method thereof

Abstract

The invention discloses a large current source for a running test of a direct-current transmission converter valve and a compensation method thereof. A No. 2 valve of a six-pulse rectifier is connected with a compensation circuit in series for load compensation, the compensation circuit is formed by connecting a series circuit and an auxiliary thyristor valve V in parallel, the series circuit is composed of a set quantity of diodes and inductors, and the purpose of compensating a three-phase unbalanced current is achieved through a set time sequence control process. According to the compensation method of the large current source for the running test of the direct-current transmission converter valve, load compensation is adopted for branch circuits with unbalanced currents in a back-to-back current source loop, the corresponding compensation circuit is arranged on the No. 2 valve, which constitutes the same phase of voltage bridge arm as that of a trial valve, so as to form a load to compensate voltage drop caused by introduction of the trial valve and the auxiliary valve, when the trial valve is cut in the entire back-to-back current source loop, direct-current components generated in a three-phase alternating-current line due to the unbalanced three-phase load are eliminated greatly, and thus, damage to a test loop and test equipment is avoided.

Description

technical field [0001] The invention relates to a large current source and a compensation method thereof for the operation test of a direct current transmission converter valve. Background technique [0002] With the transmission of electricity from west to east, the country vigorously promotes the construction of UHV DC transmission projects, and the converter valves connected in series with high-power thyristor devices have become the core of the converter stations of DC transmission projects. Its cost generally accounts for about 25% of the total project investment, and its quality directly affects the reliability of the power transmission and transformation system. Therefore, the construction of the converter valve operation test circuit to assess its operation stability is very important; [0003] The operation test of the converter valve is to effectively verify the operating characteristics of the converter valve, to ensure that the converter valve can meet the opera...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a current source for the operation test of a high-voltage DC converter valve, and at the same time provide a compensation method for using the current source for the operation test of the high-voltage DC converter valve to solve the problem when the entire back-to-back current source circuit is in the cut-in test. When testing valves, the DC component generated in the three-phase AC line due to the imbalance of the three-phase load will bring harm to the test circuit and test equipment.

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