Large-Current Output Digital Gate Driver for 6500 V, 1000 A IGBT Module to Reduce Switching Loss and Collector Current Overshoot

An 8-bit digital gate driver (DGD) using a half-bridge digital-to-analog converter IC and two power MOSFETs is proposed to enable the output voltage swing of +/- 15 V and the large gate current up to 28 A to reduce the switching loss (ELOSS) and the collector current overshoot (IOVERSHOOT) in a high-voltage, large-current IGBTmodule (HVIGBT) rated at 6500Vand 1000 A. By using the DGD to drive HVIGBT, the effectiveness of the active gate driving (AGD) is demonstrated for the first time in the world in the high-voltage and large-current range of 3.0-4.5 kV, 1000 A. The values of 1000 A, 4500V, and +/- 15Vare the world's highest records in AGD. For the purpose of investigating the optimum gate driving waveforms of AGD for HVIGBT, four different gate drive methods are compared in detail by measurements at 3.6 kV, 1000 A, and the stop-and-go gate driving is selected from a cost-performance perspective. Finally, a design guideline of AGD for HVIGBTs is clarified. The design guideline is to align the two peak heights of the collector current waveforms, thereby minimizing E-LOSS and IOVERSHOOT.

Automated summary

This article proposes an 8-bit digital gate driver (DGD) that utilizes a half-bridge digital-to-analog converter IC and two power MOSFETs to achieve a +/- 15V output voltage swing and a large gate current of up to 28A. The DGD effectively drives high-voltage, large-current IGBT modules (HVIGBT) in the 3.0-4.5kV, 1000A range, demonstrating the world's highest records in active gate driving (AGD). Four different gate drive methods are compared and the stop-and-go gate driving is selected for its cost-performance advantage. Finally, a design guideline for AGD in HVIGBTs is established to minimize switching loss (ELOSS) and collector current overshoot (IOVERSHOOT).