Reactive current loop given quantity calculation method and module and single-phase PWM rectifier control method and system

Abstract

The invention provides a reactive current loop given quantitative calculation method, which comprises the following steps that a network side real-time voltage Ua of a single-phase PWM rectifier is obtained, and according to the network side real-time voltage Ua of the single-phase PWM rectifier, a network side voltage effective value UT _ rms of the single-phase PWM rectifier is calculated; and when the grid-side voltage effective value UT _ rms of the single-phase PWM rectifier does not meet the preset condition and the single-phase PWM rectifier is not fully loaded, the given quantity Iq _ref of the reactive current loop is not equal to zero. According to the invention, the single-phase PWM rectifier is controlled to emit reactive power by controlling the given quantity Iq _ ref of thereactive current loop to be not equal to zero, so that corresponding reactive compensation is realized, a special reactive compensation device can be replaced, the cost and the occupied area are reduced, implementation is convenient, and huge economic benefits can be generated.

Description

technical field [0001] The invention relates to the technical field of traction converters for AC electrified railway locomotives, in particular to a reactive current loop given quantity calculation method and module, and a single-phase PWM rectifier control method and system. Background technique [0002] At present, my country has successively introduced, digested and absorbed foreign new locomotive and rolling stock technologies, and launched HXD series heavy-duty electric locomotives and CRH series high-speed EMUs. The PWM rectifier and the traction network realize power transmission, and the grid-side current is sinusoidal and in phase with the voltage by controlling the single-phase PWM rectifier, thereby obtaining a unit power factor. [0003] With the rapid development of railways, the traction power of AC-DC-AC electric locomotives or EMUs is increasing, and the traffic density is also increasing, which will cause a series of catenary problems, such as when the induc...

AI Technical Summary

Problems solved by technology

[0003] With the rapid development of railways, the traction power of AC-DC-AC electric locomotives or EMUs is increasing, and the traffic density is also increasing, which will cause a series of catenary problems, such as when the inductive load of the catenary is too large , will cause the voltage loss of the catenary to increase, and the voltage amplitude will be smaller than the lower limit of the normal voltage range. The upper limit of the range, and the long-term low-voltage or high-voltage operation of the catenary will bring great harm to the safety of the power grid. The system stability is poor, and it cannot withstand the impact of abnormal accidents and strong load changes on the system. It is very easy to cause large-scale power outages and system failures. collapse

To improve the current situation that the catenary voltage amplitude is too small or too large, we generally add reactive power compensation devices on the catenary line to improve the catenary voltage amplitude by compensating the reactive power on the catenary line. There will be a series of problems such as construction site and cost when upgrading and adding reactive power compensation devices to existing lines

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