Gate Drive Optocouplers For HEV Electric Motor Inverters White Paper

In sophisticated electric motor drive systems there should be a regenerative braking system that transfers energy back to the battery storage system via a charging process. The system will function as both an inverter for electric motor propulsion and as a converter/generator for the battery charging process.

Avago Technologies offers automotive grade 2.5 A gate drive optocouplers – the R2Coupler family – for use in automotive hybrid electric motor inverter/converter applications. The high output peak current drive, coupled with high voltage safety standards, certified galvanic insulation, very high common mode noise rejection isolation, solid state device level reliability, and very low power dissipation make the R2Coupler gate drivers an indispensable inverter component.

In the electric motor drive system, the inverter switches voltages in excess of 300 V. This requires safety insulation to avoid any hazards. Since this application resides under the hood in most HEVs, the operating temperature requirement is high, 125°C. Avago’s R2Coupler series is AECQ100 grade 1 qualified. These optocouplers provide reinforced insulation and reliability that delivers safe signal isolation, which is critical in automotive and high temperature industrial applications. R2Coupler devices also are able to reject high voltage transients at the high common mode voltages experienced by the inverter system during switching. Switching noise immunity ensures stable inverter and system operation.

The Avago ACPL-312T R2Coupler gate driver, with a peak output current of 2.5 A, can directly drive 1200 V/100 A insulated gate bipolar transistors in the inverter system. If higher output drive current is required, an external current buffer can be added.

Download the full White Paper below.