Direct / indirect impinging air jet cooling for power devices and application to power electronics system

As the increase in the power density of inverters, the volume of the heat sink has been a major problem. Water cooling has been the solution to reduce the size of heatsink, it has not been used for PCB based inverters because of the cost. If hot-swappable system is considered in the future, water cooling system will not be employed with the serious risk of water leakage when detaching an inverter unit. Air cooling method, on the other hand, the heat sink occupies substantial volume in the inverter system and the reduction of the volume has not been achieved for long years. And it has been required to develop downsized yet high efficiency air cooling method. In this paper, new cooling systems with impinging air jets were demonstrated and analysed to show the possibility of downsized air cooling system for PCB based inverters. A mock-up of an inverter system with the proposed cooling system was demonstrated for discussion of feasibility.