A method for improving control performances of bi-directional DC-DC boost converter in hybrid (Plug-In Hybrid) vehicles

This paper introduces a current measurement issue of a boost converter based on digital control. Due to delays in low-pass filter and current sensor, current measuring circuitry has phase delay, which depends on PWM frequency. This phase delay causes current sampling errors, which degrade the control performance. This paper investigates analytically the current sampling error caused by the phase delay and proposes a method for compensating the delay. Using this method, more precise current regulation is possible. The effectiveness of this method is proven by experimental results.