Design Study of a Future 10kW Motor Controller

Abstract: This work has the approach for how an electric motor controller should be designed. In aircraft applications it is important that the system has a high power density, and that it is reliable. The target was to find out what is possible with technology of today, and with possibilities of tomorrow. The target is to be able to compare hydraulic systems with electrical ones. The type of controllers that was studied was controllers for permanent magnetized synchronous machines (PMSM). The reason for that choice is that PMSM has a high efficiency. Different transistor technologies were evaluated. Discrete IGBT was found to be the best option. Of the evaluated transistors has IRG4PSH71U operating with a SiC freewheeling diode the best efficiency. The benefit with discrete components is that they are easy to cool, for example if they are distributed on an aluminium heatsink with forced air cooling. To minimise losses and gain controllability on the motor should the inverter be controlled with some kind of vector control, such as DTC (Direct Torque Control).