A method for fast detection of phase sequence disorder of pwm rectifier

Abstract

The invention relates to a method for quickly detecting phase sequence disorder of a PWM rectifier, belonging to the technical field of power electronic rectifiers. The method includes the following steps: S1: detecting the rectifier incoming line voltage U a , U b , U c , after performing Clark transformation on the voltage signal, U in the two-phase stationary coordinate system is obtained α and U β Component; S2: pair voltage U α and U β The component undergoes Park transformation, and the grid angle value θ is obtained after the phase-locking link; S3: According to the obtained grid angle value θ, the voltage component U α , U β Perform decoupling and decomposition to obtain the negative sequence component U of the grid voltage dn value; S4: the negative sequence component of the grid voltage U dn Perform threshold judgment, when |U dn |Exceeding the threshold U th , it is considered that the rectifier has an incoming line phase sequence disorder fault. The method provided by the invention is convenient and simple to implement, does not require additional hardware circuits for the rectifier, can effectively detect phase sequence disorder faults of incoming lines, and avoids damage to equipment caused by phase sequence disorder.

Description

technical field [0001] The invention belongs to the technical field of power electronic rectifiers, and relates to a method for rapidly detecting phase sequence disorder of a PWM rectifier. Background technique [0002] As the interface between various power electronic devices and the power grid, PWM rectifier is widely used in the fields of national production and life, effectively improving the efficiency of people's life and work. If the input and output lines of the PWM rectifier are in disordered phase sequence during use, the PWM rectifier will not operate normally, affecting the normal use of the user, and even causing safety problems in severe cases. Therefore, it is very necessary to detect the phase sequence disorder of the PWM rectifier. [0003] The traditional phase sequence disorder detection method usually uses hardware circuit to distinguish the three-phase phase sequence. On the one hand, it needs to increase the hardware cost. On the other hand, it is not ...

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Problems solved by technology

[0003] The traditional phase sequence disorder detection method usually uses hardware circuits to distinguish the phase sequence of the three phases. On the one hand, it needs to increase the cost of hardware. On the other hand, it is not suitable to add hardware circuits in some mature equipment.

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