REGULATED POWER SUPPLY WITH IMPROVED POWER FACTOR AND UNINTERRUPTIBLE POWER SUPPLY

摘要

PURPOSE:To improve the power factor of a power supply by simple circuit constitution without changing a fundamental circuit section in a capacitor input type half-wave rectifier circuit stepping up the positive side and the negative side respectively to a common line. CONSTITUTION:In a regulated power supply, in which each one of AC input- output lines is coupled and used as a common line 16, each half-wave rectified DC voltage is stepped up by a step-up chopper circuit 31 in the forward direction and a step-up chopper circuit 32 in the negative direction, and these DC voltage is converted into ACs again and output, the step-up chopper circuit 31 in the forward direction and the step-up chopper circuit 32 in the negative direction are employed as filters for improving a power factor respectively. The waveform of input currents is approximated to input voltage by using a signal obtained by adjusting output voltage by a phase adjusting circuit or employing input voltage as it is and formed in a phased sine wave shape by these filters 31, 32 for improving the power factor functioning as the step-up chopper circuits in combination.