PHASE ANGLE ACQUISITION METHOD AND SYSTEM

摘要

A phase angle acquisition method and system. The method comprises the following steps: collecting a first-phase input voltage and a second-phase input voltage in a three-phase input voltage of a three-phase controllable rectification system; according to the first-phase input voltage and the second-phase input voltage respectively collected at two successive sampling moments, recognizing a phase sequence of the three-phase input voltage; when the phase sequence of the three-phase input voltage is a positive phase sequence, according to a first correlation between a voltage vector phase angle and the three-phase input voltage, acquiring a voltage vector phase angle θ(k) ＝ θ0 + ω*ΔT; and when the phase sequence of the three-phase input voltage is a negative phase sequence, according to a second correlation between the voltage vector phase angle and the three-phase voltage, acquiring a voltage vector phase angle θ(k) ＝ -θ0 - ω*ΔT. A voltage vector phase angle acquired thereby can be directly applied to a system control program, there is no need to perform fault-phase protection, and there is no requirement for the wiring of an input power voltage. The present invention effectively solves the problem that an existing phase angle acquisition method has relatively low intelligence, is inconvenient to apply and has low error-tolerant rate.