Current-sensor-less Control with Fast Transient Response for Pulsed Power Load

Rapid switching between peak and valley currents of pulse power loads poses a challenge for current tracking in point-of-load converters. Current mode control with a load current reference is a common method for improving the transient response. However, multiple current sensors sampling peak currents are required in this method, potentially increasing the cost and size of the power supplies. Therefore, a current-sensor-less control method is proposed in this article. The load current reference is divided into inductance and capacitance current components. Because the inductor current also serves as the feedback signal, it is cancelled out, leaving only the capacitance current term. By sampling the single capacitance current to represent the entire capacitor array current, a small-range and cost-effective current sensor can be used. Furthermore, the differential of the capacitance voltage is used to obtain the equivalent capacitance current so that the current sensors are eliminated. Experimental results verify the feasibility of the proposed method.