Title :
Use of leading-edge modulation to transform boost and flyback converters into minimum-phase-zero systems
Author :
Sable, Dan M. ; Cho, Bo H. ; Ridley, Ray B.
Author_Institution :
Bradley Dept. of Electr. Eng., Virginia Polytech. Inst. & State Univ., Blacksburg, VA, USA
fDate :
10/1/1991 12:00:00 AM
Abstract :
In leading edge modulation, the pulse width modulated (PWM) signal is turned off at the clock signal and turned on when the error signal crosses the ramp waveform. It is shown that the positive zero in the power stage transfer function of boost and flyback regulators can be shifted into the left-half-plane under suitable conditions. These conditions are as follows: (1) leading edge modulation must be used in the pulse width modulator; (2) the feedback compensation must not average the capacitor EST-generated output voltage switching ripple; and (3) appropriate power stage parameter values are necessary. The design procedure for shifting the positive zero into the left-half-plane is presented. Experimental verification is provided
Keywords :
control system synthesis; feedback; power convertors; pulse width modulation; switching; transfer functions; PWM; boost; capacitor; clock signal; design; error signal; feedback compensation; flyback; leading edge modulation; power convertors; ramp waveform; switching; transfer function; Capacitors; Clocks; Equations; Frequency; Pulse modulation; Pulse width modulation; Pulse width modulation converters; Switches; Transfer functions; Voltage;
Journal_Title :
Power Electronics, IEEE Transactions on
