Apparatus and method in connection with crane sheave

Adjustable transformer for a model vehicle

Power supply apparatus, power supply system, and method for controlling power supply system

Energy storage device, system with energy storage device and method for generating a supply voltage of an energy storage device

Power control apparatus and power control method

Method and apparatus for regulator control

Capacitor-based active balancing for batteries and other power supplies

Electric power control system and method

Method and arrangement for improved controllability of fuel cell stacks