Flexible direct current power transmission converter performance testing platform and control method thereof

Abstract

The invention provides a flexible direct current power transmission converter performance testing platform and a control method thereof. The direct current side of a first modularized multi-level converter and the direct current side of a second modularized multi-level converter are connected in a back-to-back mode, and three phases of the alternating current side of the first modularized multi-level converter are connected with three phases of the alternating current side of the second modularized multi-level converter correspondingly, so that a power circulation pathway is formed; a test power source is in parallel connection with the direct current side of the first modularized multi-level converter and the direct current side of the second modularized multi-level converter and provides loss power for steady-state operation testing; a short circuit generator is in parallel connection with the direct current side of the first modularized multi-level converter and the direct current side of the second modularized multi-level converter. According to the testing platform and the control method thereof, the requirement for power grid capacity is low; meanwhile, the direct current side power supply mode is adopted in the testing platform, and therefore the single test power source is adopted for the whole platform. With regard to test items of the short circuit and over-current turn-off required by IEC standards, due to the fact that the basic structure of the platform is basically the same with that of practical engineering, the short circuit test and the over-current turn-off test can be set through the platform according to double-pole short-circuit faults in a practical flexible direct current power transmission system.

Description

technical field [0001] The invention relates to a system in the technical field of testing high-voltage and high-power power electronic converters, in particular to a modular multi-level flexible direct current transmission converter performance testing platform and a control method thereof. Background technique [0002] Flexible DC transmission technology is a new type of power transmission technology based on voltage source commutation VSC technology and fully-controlled power devices (IGBT, IEGT) with gates that can be turned off. Compared with traditional DC transmission technology, it has the ability to connect weak AC systems. , Power supply to the passive network, improve the penetration power of wind power and other new energy sources connected to the grid, etc. With the continuous development of flexible DC converter technology at home and abroad in recent years, its voltage level and transmission capacity are also increasing, and it has begun to be applied to my co...

AI Technical Summary

Problems solved by technology

However, this device can only perform steady-state operation tests. The literature does not mention the short-circuit and over-current shutdown tests required by the IEC standard, and the topology of the device is quite different from the converter structure in actual engineering applications. Although it can produce stable The equivalent bridge arm current in normal operation, but the control strategy adopted needs to be specially designed, which is different from the actual operating equipment, so it is impossible to carry out algorithm-level test on the adopted converter control strategy

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