Feedforward control of DC-DC PWM boost converter

• Published in: IEEE transactions on circuits and systems. 1, Fundamental theory and applications Vol. 44; no. 2; pp. 143 - 148
• Main Authors: Kazimierczuk, M.K., Massarini, A.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.02.1997; Institute of Electrical and Electronics Engineers
• Subjects: Applied sciences; Capacitors; DC-DC power converters; Electrical engineering. Electrical power engineering; Exact sciences and technology; Negative feedback loops; Power electronics, power supplies; Proportional control; Pulse circuits; Pulse width modulation; Pulse width modulation converters; Steady-state; Voltage control; Voltage measurement; Control circuit; Circuit design; Network analysis; Performance characteristic; Direct current convertor; Power electronics; Feedforward; Pulse duration modulation; Steady state
• ISSN: 1057-7122; 1558-1268
• DOI: 10.1109/81.554332

A new feedforward control circuit suitable for applications in the dc-dc pulsewidth modulated (PWM) boost converter operated in the continuous conduction mode (CCM) is proposed. Its principle of operation is described, analyzed for steady state, and experimentally verified. The peak value of the sawtooth voltage at the noninverting input of a PWM modulator is held constant and the voltage at the inverting input of the PWM modulator varies in proportion to the converter dc input voltage. As a result, the complement of the on-duty cycle (1-D) is proportional to the dc converter input voltage, yielding the converter output voltage theoretically independent of the converter input voltage. The circuit is very simple and significantly improves line regulation of the output voltage. The measured open-loop line regulation at fixed loads was less than 5% for the converter dc input voltage change by 400%. The load regulation was also good even without a negative feedback loop.