Bus voltage control using gated fixed energy pulses

摘要

Voltage on a DC power bus is controlled using gated fixed energy pulses. The power bus includes a bus capacitor for storing charge and can have a varying load. A battery is provided for providing electrical power to the bus through a power boost circuit including a boost switch for selectively applying a pulse of a fixed amount of energy to the bus in response to comparison of the bus voltage and a first reference voltage. The power boost circuit can include a choke coil and a timer for establishing an on time and an off time for each pulse, the on time establishing the amount of energy to be delivered to the bus, and the off time allowing the energy to be delivered to the load. A shunt path including a shunt switch can be provided for shunting energy from the bus when the bus voltage reaches a second reference voltage higher than the first reference voltage. In a preferred embodiment, the shunt path shunts energy to the battery for recharging the battery.