Control method and device of converter

Abstract

The invention discloses a control method and device of a converter. The method is suitable for an electric locomotive traction system, wherein the electric locomotive traction system comprises the converter, an upper-layer controller and a digital signal processor; and the method comprises the steps as follows: the digital signal processor carries out proportional and integral regulation according to a difference value between a set value of an output voltage of a DC side and the output voltage to obtain a first effective component; the upper-layer controller transmits an instruction of generating demanded power of a load to the converter; the converter transmits the demanded power generated on the basis of the instruction to the digital signal processor; and the digital signal processor divides an effective value of a grid side voltage by the demanded power to obtain a second effective component, calculates the sum of the first effective component and the second effective component to obtain the set value of a grid side current and processes the set value of the grid side current to generate a drive signal of driving the converter, so that the target of improving the dynamic response speed of the vehicular grid side converter and the anti-jamming capability on load disturbance under the premise of not increasing the complexity and the cost of the system is achieved.

Description

technical field [0001] The present invention relates to the technical field of converter control, and more specifically, to a control method and device for a converter. Background technique [0002] The electric locomotive traction system realizes AC and DC power conversion through pantographs, traction transformers, grid-side converters and inverters to drive the traction motors. Among them, the grid-side converter is an important part of the AC and DC conversion of the electric locomotive traction system. It can provide a stable DC voltage for the rear-stage traction inverter, and can also make the power factor of the catenary or traction transformer side close to In 1 or -1, so as to realize the two-way flow of energy. Therefore, it is very important to control the vehicle grid-side converter. [0003] In the prior art, a commonly used control method for the on-vehicle grid-side converter is the transient current control method. The control method adopts a double-close...

AI Technical Summary

Problems solved by technology

The control method adopts a double closed-loop control method of voltage outer loop and current inner loop control, in which, the voltage outer loop control uses the DC side voltage multiplied by the DC side current to obtain the load power, which requires adding a DC side current sensor to measure the DC current. The current on the DC side not only increases the complexity and cost of the system, but also the DC side current fluctuates and the output is unstable

In addition, when the load changes sharply, when the current output by the transient current control method cannot follow the load change in time, it will cause a sudden increase or decrease in the intermediate voltage, which will further affect components such as DC side support capacitors and insulated gate bipolar transistors. Cause damage, thereby affecting the dynamic response speed of the vehicle grid-side converter and the anti-interference ability to load disturbance

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