APPARATUS FOR DETECTING THE 3-PHASE SOURCE VOLTAGE OF A PULSE WIDTH MODULATION CONVERTER FOR CALCULATING THE PHASE ANGLE OF SOURCE VOLTAGE BY USING A STATE SECTION CLASSIFIED ACCORDING TO THE SIGN OF THE SOURCE VOLTAGE OF EACH PHASE, A PHASE ANGLE RANGE, AND THE FREQUENCY OF THE SOURCE VOLTAGE

摘要

PURPOSE: An apparatus for detecting the 3-phase source voltage of a pulse width modulation (PWM) converter is provided to reflect the frequency change of source voltage to quickly calculate a phase angle, thereby operating stably the PWM converter.;CONSTITUTION: An apparatus (100) for detecting the 3-phase source voltage of a PWM converter (200) comprises a rectifier (110), a digital signal converter (120), and a control unit (130). The rectifier includes a plurality of diodes which is electrically conducted or blocked according to the sign of each phase of source voltage supplied to the PWM converter. The digital signal converter outputs a digital signal corresponding to both-end voltage of the diodes for each phase inputted from the rectifier. The control unit calculates the phase angle of the source voltage by using the digital signal inputted from the digital signal converter and the frequency of the source voltage.;COPYRIGHT KIPO 2013;[Reference numerals] (120) Digital signal converter; (130) Control unit; (131) Digital signal input unit; (133) Analogue/digital converter; (135) PWM signal generator