A method and medium for output voltage balance control of train auxiliary converter

Abstract

The invention discloses a method for controlling output voltage balance of a train auxiliary converter, which adopts a double-loop control in which a positive sequence control loop and a negative sequence control loop are synchronously combined; in the positive sequence control loop, the load terminal phase voltage u of the auxiliary converter a , u b , u c and phase current i a i b i c Get the positive sequence control output u in the two-phase coordinate system α+ * and u β+ * ;In the negative sequence control loop, through the auxiliary converter load terminal phase voltage u a , u b , u c Get the negative sequence control output u in the two-phase coordinate system α‑ * and u β‑ * ; then through u α+ * , u β+ * with u α‑ * , u β‑ * Get the total control output u α * , u β * , to control the driving pulse signal of the three-phase inverter in the train auxiliary converter. The present invention also discloses a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the above-mentioned control method is realized. Both the control method and the medium of the invention have the advantages of ensuring the balance of the output voltage and the like.

Description

technical field [0001] The invention mainly relates to the technical field of rail transit, in particular to a method and a medium for controlling output voltage balance of a train auxiliary converter. Background technique [0002] When some unbalanced loads are introduced into the train auxiliary converter, the output three-phase voltage will be unbalanced; in addition, the abnormal operation and damage of the load will also cause the voltage to appear obviously unbalanced. The unbalance of the output voltage of the auxiliary converter will not only cause the overheating of the cable due to the excessive current of the neutral line, but also reduce the capacity utilization of the transformer, increase the loss of the transformer, and endanger the safe operation. What's more serious is that the unbalanced three-phase output voltage will interfere with the normal operation of on-board load equipment such as motors and power electronic converters, ultimately reducing the servi...

AI Technical Summary

Problems solved by technology

The current common practice is to introduce an intima controller that can track high-order pulsation components with zero steady-state error in the traditional proportional-integral controller, such as a resonant controller, a repetitive controller, etc.; where the gain of the resonant controller to the pulsation component is affected by the system The frequency is directly affected, especially for the performance of the parallel system of the train auxiliary converters, which changes in real time with the load power distribution; the repetitive controller will affect the dynamic response of the system due to the inherent delay of a power frequency fundamental cycle performance

In addition, in the method of controlling the positive and negative sequence variables in the positive sequence and negative sequence coordinate systems respectively, since the controlled variables in the respective coordinate systems all represent DC components, no static error tracking can be realized based on the traditional proportional-integral controller. The positive and negative sequence separation of the output unbalanced voltage usually depends on the digital filter, which affects the dynamic response performance and control stability of the system

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