Improved Set-Point Tracking and Disturbance Rejection of DC-DC Converters Using Voltage-Mode Digital Control

• Published in: IEEE journal of emerging and selected topics in power electronics Vol. 9; no. 3; pp. 3276 - 3286
• Main Authors: Kobaku, Tarakanath, Rao, Vinayak, Patwardhan, Sachin C., Agarwal, Vivek
• Format: Journal Article
• Language: English
• Published: Piscataway IEEE 01.06.2021; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Compensators; Continuous conduction mode (CCM); Converters; dc-dc boost converter; DC-DC power converters; Digital control; disturbance rejection; Electric potential; Feedback control; Sensors; Servomotors; Simulation; Voltage; Voltage control; voltage regulation; Windup
• ISSN: 2168-6777; 2168-6785
• DOI: 10.1109/JESTPE.2020.2999955

In this article, a voltage-mode control scheme with two degrees of freedom is developed for improving servo and regulatory responses of a boost-type dc-dc converter operated in the continuous conduction mode. The servo behavior is shaped using two model-based digital controllers, namely modified Dahlin's controller (MDC) and the Vogel-Edgar controller (VEC). To handle input saturation during the transients, a novel antireset windup scheme is proposed and integrated with VEC and MDC. To improve the regulatory response, without altering the design of VEC or MDC, a model-based robust internal-loop compensator (RIC) is introduced, which attempts to reject unmeasured disturbances before the feedback controller can start reacting to their effects. To assess the efficiency of the proposed integrated control scheme, simulation studies and experimental verifications have been carried out for a variety of servo and regulatory scenarios. Analysis of simulation results reveals that if tuning parameters of the RIC are chosen judiciously, then the proposed scheme significantly improves the regulatory behavior of VEC and MDC without significantly altering their servo behavior. The closed-loop responses obtained in the experimental evaluations closely resemble the responses of simulations and corroborate conclusions reached through the analysis of simulation results.