Reactive current loop given amount calculation method, rectifier control method and system

Abstract

The present invention provides a reactive current loop given quantity calculation method, comprising: obtaining the real-time voltage U of the grid side of the single-phase PWM rectifier a , according to the real-time voltage U of the grid side of the single-phase PWM rectifier a Calculate the effective value U of the grid side voltage of the single-phase PWM rectifier T_rms ; When the single-phase PWM rectifier network side voltage effective value U T_rms When the preset conditions are not met and the single-phase PWM rectifier is not fully loaded, the given value I of the reactive current loop q_ref not equal to zero. The present invention controls the given quantity I of the reactive current loop q_ref It is not equal to zero to control the reactive power of the single-phase PWM rectifier to realize the corresponding reactive power compensation, which can replace the special reactive power compensation device, save cost and land occupation, easy to implement, and can generate huge economic benefits.

Description

technical field [0001] The invention relates to the technical field of traction converters for AC electrified railway locomotives, and in particular to a reactive current loop given amount calculation method, a rectifier control method and a 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 inductive load of the catenary is...

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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