A Power Control Unit (PCU) has been developed for the Integrated Motor Assist (IMA) system employed in the new model INSIGHT. The development aimed to reduce the overall size, height, and weight of the PCU in order to realize a layout that positioned it under the floor of the rear trunk. Contiguous positioning of the DC-DC converter and the inverter in the PCU has reduced the area required for mounting the unit, in addition to enabling the DC-DC converter input filter to be removed and the number of terminals reduced. This has contributed to the realization of size and cost reductions. The total height of the DC-DC converter has been reduced through the use of copper wire printed on a substrate for part of the main transformer winding wire, contributing to the reduced height of the PCU. The use of a smoothing capacitor with the electrostatic capacity reduced by half enabled reductions in size and cost. In addition, the use of beam leads for the internal wiring of the transfer-molded power module (TPM), together with connections made by direct lead bonding (DLB), enabled the production process to be simplified and costs reduced.
Article of Honda R&D Technical Review Vol.21 No.1 (95 - 100)