A control system for a power converter includes a digital reference signal generator, a first proportional-integral (PI) controller, a second PI controller, and a diode. The digital reference signal generator is configured to operate in a maximum peak power tracking (MPPT) mode of operation and an output voltage control mode of operation. In the MPPT mode of operation, the digital reference signal generator is configured to receive an input voltage and an input current provided to the power converter and provide an input voltage reference signal based on the input voltage and the input current. In the output voltage control mode of operation, the digital reference signal generator is configured to provide a constant input voltage reference signal.