30 November 2017
DC-DC power convertors, electric current control, microcontrollers, PWM power convertors, digital control, power engineering computing, control engineering computing, digital PWM control strategies, digital pulse-width-modulation control strategies, high-power dual-interleaved DC-DC converters, current sharing, digital peak current control, multisample averaged current, enhanced single-sample averaged current control, TMS320F28377D, stability requirements, silicon carbide DC-DC converter, enhanced single-sample method, multisampled technique, dynamic response, duty ratios
Three pulse-width-modulation (PWM) digital control approaches are evaluated to provide the current sharing between phases in high-power dual-interleaved DC–DC converters. The implementation of a digital peak current, multi-sample averaged current and an enhanced single-sample averaged current control in a TMS320F28377D is described. A summary of stability requirements is provided for designing the controllers and experimental results from a 60 kW, 75 kHz silicon carbide DC–DC converter are used to evaluate the steady-state and dynamic performance of the three control methods. Overall the best performance in terms of tracking and speed of response was achieved by the enhanced single-sample method. The multi-sampled technique provided the highest tracking accuracy, but at the expense of the slowest dynamic response. The fastest dynamic response was achieved by the digital peak current control, but this method is limited by poor noise immunity and instability for duty ratios in the region of 0.5.