The invention discloses a control method of a railway power
regulator based on a half-bridge structure. The railway power
regulator based on the half-bridge structure is composed of two half-bridge arms, and the two half-bridge arms are connected with each other by two capacitors. Since the
voltage at the DC side is powered by two series capacitors, the problem of
voltage sharing exists. In orderto realize
voltage sharing at the DC side, a voltage sharing
PI regulator is used for controlling the deviation of the two
capacitor voltages, and the offset output by the voltage sharing
regulator directly influences the charging and discharging current of the two capacitors, thereby reducing the deviation to 0. In order to keep the voltage at the DC side stable, the voltage external ring at theDC side uses a PI controller to regulate the output value, and the output value is respectively multiplied by the
synchronizing signals of the two power supply arms, and superposed by the
harmonic and negative sequence compensating current reference
signal obtained by computation according to the VV
traction system negative sequence and the
harmonic compensation principle, thereby obtaining the current reference
signal of the two half-bridge
converters. In order to realize quick tracking of internal
ring current, a
hysteresis control method is used for the output currents of the two
converters, so that the currents from the output ends of the two
converters track the reference compensating
signal, thereby realizing negative sequence and
harmonic compensation.