A kind of apf system and judging method for judging the space position of voltage vector

Abstract

The invention discloses an active power filer (APF) system for judging the spatial position of a voltage vector. The APF system comprises a three-phase AC circuit composed of a non-linear load, an APF main circuit and an APF control circuit. The invention also discloses a method for judging the spatial position of the voltage vector by using the APF system. The method comprises the following steps of: 1, acquiring a voltage spatial vector u<*> and projections ua<*>, ub<*> and uc<*> of the voltage spatial vector in a three-phase stationary reference frame abc; 2, dividing a region on which the voltage spatial vector u<*> is located into 12 parts according to monotonous increase / decrease trend of the ua<*>, ub<*> and uc<*>; and 3, converting the 12 parts into a logic expression, namely, the judgment on the spatial position of the voltage vector. In the method, the monotonous increase / decrease trend problem of the voltage spatial vector us<*> in the three-phase stationary reference frame abc is considered, so that the division of the region on which the voltage spatial vector us<*> is located is much more precision; and meanwhile, power supply reliability of a load is improved, system control precision is obviously improved, and thus, power supply quality is practically guaranteed.

Description

technical field [0001] The invention belongs to the technical field of power distribution control, and relates to an APF system for judging the space position of a voltage vector, and also relates to a method for judging the space position of a voltage vector by using the system. Background technique [0002] In recent years, with the extensive use of power electronic devices in the power system, reactive power and harmonic components are continuously injected into the grid, resulting in three-phase unbalance, flicker and harmonics in the grid voltage, which affects the utilization efficiency of the grid. and power quality, and even threaten power grid security. As an effective harmonic suppression and reactive power compensation device, active power filter (APF) has gradually become a hot topic in the field of engineering research. Therefore, in-depth research on the control and implementation of APF has certain positive significance for the promotion and application of AP...

AI Technical Summary

Problems solved by technology

The traditional method uses the positive and negative of the line voltage to change u s * The space is divided into 6 areas, this division method does not consider u s * The monotonous increase / decrease problem in the three-phase static abc coordinate system directly affects the selection of the switch state, greatly reduces the control precision and accuracy of the APF system, and also limits the popularization and application of the hysteresis space vector control in the APF system

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