Economic UPS structure with phase-controlled battery charger and input-power-factor improvement

A new single-phase uninterruptible power supply (UPS) scheme is proposed. Its advantages when compared with existing UPSs are: no transferring time; high efficiency; low implementation cost; and high power density. It mainly consists of a minimised power converter which is capable of providing specified constant output voltage, a phase-controlled battery charger and input power factor improvement. The experimental results of the developed prototype show superior performance