Wattless current tracking method of static var compensator based on power balance

Abstract

The invention provides a wattless current tracking method of a static var compensator based on power balance, which comprises the following steps: firstly, sampling three phases of phase voltage and phase current of the low voltage side of a transformer; calculating wattless power required by a load; using the calculated wattless power as the wattless power output reference valve of STATCOM; and calculating the pure wattless reference current required to be output by STATCOM through combining the voltage of a compensating point so that the compensated wattless power is balanced with the wattless power required by the load when the actual output current equals to the pure wattless reference current. The pure wattless reference current carries out dq0 decomposition, the wattless component of the total reference current can be extracted, and the PI link output for controlling the direct current capacitance voltage of the STATCOM is used as wattful component of the total reference current, so the wattful component and the wattless component of the current can respectively carry out current PI control, and the output of the STATCOM can be controlled. In the invention, the setting of the compensating point of the STATCOM is not limited by the load current measuring point, and the compensating point can be flexibly set at each side of the transformer, so the size of the output voltage and the compensating current of the compensator can be reasonably selected.

Description

technical field

[0001] The invention relates to a control method of a static var compensator, in particular to a reactive current tracking method of a static var compensator based on power balance. Background technique

[0002] In the power distribution system, in order to improve the power factor of the high-voltage side of the distribution transformer and improve the power quality of the power grid, a reactive power compensation device is usually installed on the low-voltage side of the distribution transformer. Static var compensator (hereinafter referred to as STATCOM) is a widely used reactive power compensation device. During the operation of STATCOM, it is necessary to dynamically compensate the reactive power required by the load. When the reactive power required by the load changes When , it is required that the reactive power output by STATCOM can also be automatically tracked and compensated, which is realized by STATCOM's reactive current tracking method. [000...

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