Patent ID: 6175311
Filing Date: 2001-01-16
Classification: H02J

Abstract:
An ON-LINE uninterrupted power supply (UPS) controllable from far end, comprising:an AC/DC converter utilized to convert an AC input power into a DC power by a bridge rectifier for supplying power to a transformer, a transistor, and a pulse width modulator (PWM) to oscillate and create a higher voltage signal which is then rectified by a diode to in turn supply a stable high voltage DC power for a DC/AC inverter and a battery in virtue of a cooperative feedback circuit including a Zener diode and a photocoupler, wherein said PWM at high efficiency is capable of permitting omni-range AC input power and isolating the primary AC input power from said battery to avoid electric shock when replacing the latter;a charger using the high voltage DC power to charge said battery in a manner of limited voltage and current under rated values via a transistor switching circuit and a Zener voltage regulating diode when the civil power is available to ensure a safe and best charge process;a battery detector being provided with a component voltage rendered by a resistive voltage divider to notify a controller to shut down said battery in time for prolonging lifetime of the latter;a DC/DC booster utilized to boost the battery voltage in case of civil power failure to supply a high voltage power to a DC/DC inverter via a PWM, a transistor, a transformer, and a rectifying diode;said DC/AC inverter used to change the DC voltage output of said AC/DC converter or the high-voltage output of said DC/DC booster into a sinewave voltage output via a driver, a power transistor, and an electric inductor;a ring detector further comprising a capacitor, a bridge rectifier, and a photocoupler used to fetch a ring signal and notify said controller to enable or disable power output; andsaid controller composed of some electronic elements or a microcontroller plus a control program to thereby control said DC/DC booster, a power indicating light, and said DC/AC inverter for output of an AC power according to conditions of the power switch, charge quantity of the battery, ring signal, and status of the output power;wherein said ring detector is ready to detect a ring signal for ON/OFF the output power for power management; and said AC/DC converter adopts said PWM to effectively isolate the primary AC power from said battery for safe replacement of the latter and permit omni-range AC input power to ensure safe operation.