Abstract: A duty cycle controller apparatus for producing a duty cycle signal for controlling switching of switches of a battery charger having an AC input for receiving power and an output for supplying power to charge a battery in response to switching of the switches, while maintaining a high power factor at the AC input. The duty cycle controller apparatus includes a current command signal generator having a plurality of signal inputs for receiving a plurality of signals representing a plurality of operating conditions of the charger, a plurality of current command outputs and a processor operably configured to generate a plurality of current command signals at the current command outputs in response to respective sets of operating conditions.

Abstract: A system having input terminals including line and neutral terminals for receiving AC power from a first AC source and having output terminals including output line and neutral terminals for receiving AC power from output terminals of a second AC source and for supplying AC power to a load, has a transfer switch configurable to connect the input terminals to the output terminals or to isolate the input terminals from the output terminals. When the transfer switch is configured to isolate the output terminals from the input terminals, the second AC source is caused to cease supplying power to the output terminals when after phase shifting the voltage produced by the second source the voltage at the input terminals is in-phase with that voltage.

Abstract: A DC link power converter apparatus including a first DC to DC converter, a DC to AC converter and a load balancing storage element. The first DC to DC converter has first and second DC ports and the DC to AC converter has a third DC port and has an AC port. The first DC port is connectable to a DC source and the second DC port is connected to the third DC port. The AC port is connectable to an AC load. The load balancing energy storage element is connected to the second DC port for decoupling the DC to DC converter from the DC to AC converter by supplying energy to the third DC port when a voltage at the second DC port is tending to decrease and for storing energy received from the second DC port when a voltage at the third port is tending to increase.