Hardware-in-the-Loop Systems with Power Electronics: A Powerful Simulation Tool

The chapter points out that sequential switching is not only applicable to IGBT modules with integrated diodes mounted closely on a heat sink, but also to complete industrial standard two-level voltage source inverters (VSIs). Thus, the power capability and the overall switching frequency of these products can be increased by using several of them in parallel with sequential switching. Using this approach, a novel electrical test bench for drive inverters can be set up with a minimum effort on design and development. This provides an alternative for manufacturers of drive inverters to test their complete product range under real power levels without the requirement for a multitude of real machines. The discussion provided in the chapter proves that the so called virtual machine (VM) is a Hardware-in-the-Loop system allowing an inverter to be tested at real power levels without the need for installing and operating real machines. The VM has the same characteristics as a real induction motor or even a synchronous motor. Different machines and their respective load conditions can be emulated by software, which means that the drive inverter under test can operate in its normal mode (as usual). No modification has to be done to the inverter or to the control unit.