SIngle Phase AC Voltage Regulation Using Back-to-Back SCRs

Single-phase AC voltage controller using anti-parallel thyristors feeding an RL load. Phase-angle control regulates RMS output voltage.

This model simulates a single-phase AC voltage controller using two anti-parallel thyristors supplying an RL load. The firing angle of the thyristors is controlled to vary the RMS output voltage applied to the load. The RL load introduces phase shift and current lag, allowing observation of conduction intervals and waveform distortion.

Input voltage, output voltage, load current, and firing pulses are measured to study phase control behavior and the effect of firing angle on RMS voltage and current.

Main features

• Anti-parallel thyristor configuration
• Phase-angle firing control
• RL load behavior and current lag
• Measurement of voltage, current, and pulses
• Suitable for study of AC voltage controllers and SCR phase control