Grounding system and apparatus

Abstract

A grounding system for a semiconductor module of a variable speed drive includes a first conductive layer, a second conductive layer; a substrate disposed between the first conductive layer and the second conductive layer; and a base attached to the second conductive layer, the base being connected to earth ground via a grounding harness. The first conductive layer is in electrical contact with the semiconductor module and the substrate, and electrically insulated from the second conductive layer by the substrate. The second conductive layer is in electrical contact with the substrate and disposed between the substrate and the base in electrical communication with an earth ground. The first conductive layer, the substrate and the second conductive layer form a capacitance path between the semiconductor module and the base as well as electrical conductors and the base for reduction circulating currents within the semiconductor module.

Description

[0001] Mutual reference of related applications [0002] This application claims the priority and benefits of U.S. Provisional Application No. 61 / 081933 entitled "Grounding system and apparatus" filed on July 18, 2008, which is hereby incorporated by reference. Technical field [0003] This application relates generally to grounding systems. The present application more specifically relates to grounding systems for semiconductor power components with non-conductive heat sinks. Background technique [0004] Variable speed drives (VSD) used in heating, ventilation, air conditioning, and refrigeration (HVAC&R) applications can use heat sinks or cooling blocks for the installation of semiconductor devices such as insulated gate bipolar transistor semiconductor switches and their Carry out heat management. The heat sink may be composed of a metal having a high thermal conductivity, such as copper. However, metal heat sinks are expensive due to the material and labor costs associated w...

AI Technical Summary

Problems solved by technology

The parasitic currents and charges may interfere with the control signal for the semiconductor module, causing some of the semiconductor devices within the module to go into the "ON" or conductive state when they should be in the "OFF" or non-conductive state by the control signal

Plastic or non-conductive heat sinks electrically insulate the base of the semiconductor module from the rest of the system; therefore, any parasitic currents caused by the rate of change of voltage applied to the module may circulate in the module, potentially interfere with low-level control signals and cause the module to malfunction

Images