Power module control design

The control and interface circuits for power transistor modules that are used in 50 to 100 kW motor drives are difficult to design because of the 400 to 600A currents, 400V operating levels, and fast switching times. Each of the power module control design functions is examined, as well as futuristic semiconductor devices that will simplify the control circuit. These functions include: logic-to-power module interface, DC-DC gate bias power supply, IGBT gate driver, overcurrent protection, temperature sensing, undervoltage shutdown, and fault output interface. The module control functions are usually located on an external printed circuit board. Recent progression in power IGBT modules have improved the ease of interfacing to the power module by locating the control circuit board in the module. These "smart" modules, while easier to use, cost more and place pre-defined limits on circuit flexibility. An alternative modular approach is shown.