Heat Dissipation Balancing in a Switched Reluctance Drive by Combined Use of Active and Passive Thermal Control Methods

Abstract

Air-cooled heatsinks for electric drives often suffer from unbalances in the heat dissipation capability when several power modules are mounted on the same heatsink, eventually limiting the output power to that dictated by the hottest module. This paper discusses the options for the placement of the power modules on the heatsink for the particular case of switched reluctance drives. Combined with active thermal control methods, this reduces the temperature dispersion, and therefore allowso toincrease the maximum output power of the converter.

Temperature Gradient Improvement of Power Semiconductor Modules Cooled Using Forced Air Heat Sink

“…In terms of steady-state operation, the set of equations ( 7) can be reduced to the following expression, where the components providing the circuit dynamic performance are omitted: (9) The power loss generated in IGBTs operating under conventional balanced mode is the same in each power semiconductor module. Therefore, for further analysis, it can be replaced as P = P 1 = P 2 = P 3 .…”

“…4. The circuit was derived from the approach presented and discussed in [9], [11], [13], [14]. According to the equivalent circuit, it can be seen that the temperature of each section of the heatsink T A , T B , and T C are defined as follows:…”

A Test Rig for Thermal Analysis of Heat Sinks for Power Electronic Applications

“…The goal in developing a system that includes power components is therefore to keep the temperature gradient of the components as evenly distributed as possible. This can be done by mechanically modifying the heat sink [10]- [12] or by so-called active thermal control [13], [14]. The latter requires the use of sensors and control technology to measure the temperature of the semiconductor component and to regulate the control of the fan as well as the control of the component.…”