Series converter based on Si IGBT/SiC MOS hybrid parallel devices, and fault operation control method thereof

Abstract

The invention discloses a series converter based on Si IGBT / SiC MOS hybrid parallel devices, and a fault operation control method thereof. The converter is of a half-bridge structure, an upper bridge arm and a lower bridge arm are each formed by connecting (n + r) hybrid parallel devices in series, n devices maintain normal operation, r devices are used as redundancy, each hybrid parallel device is formed by connecting a SiC MOSs and b IGBTs in parallel, each IGBT / SiC MOS comprises a driver, and the converter comprises a total central controller and is responsible for driving sequence, state monitoring and control strategy adjustment of devices. If a certain power device in the converter fails, the fault operation control strategy can judge the failure position in a switching period, uploads the operation condition of the converter, and adopts the control strategy to maintain normal operation. The converter provided by the invention considers the advantages of high voltage, high power, high frequency and high power density, and the provided fault control strategy can ensure that the converter continues to operate normally under the condition of device faults, so that the fault tolerance of the system is improved.

Description

technical field [0001] The invention relates to the technical field of power electronics, in particular to a series converter based on a Si IGBT / SiC MOS hybrid parallel device and a fault operation control method thereof, belonging to the technical field of high-voltage high-power converters. Background technique [0002] At present, power electronic technology is widely used in many fields such as motor drive, flexible DC and uninterruptible power supply. Industrial applications have higher and higher demands for high voltage and high power of power electronic converters. Due to the constraints of on-resistance, device structure and production process, the voltage level of a single power device cannot meet the application requirements. Therefore, in some applications, the device is connected in series. Increase the voltage level of power electronic converters to meet application requirements. At the same time, in order to reduce the volume and weight of the converter, high...

AI Technical Summary

Problems solved by technology

The failure of a power device in the series converter based on SiC MOSFET will cause the shutdown of the entire converter, the reliability of the converter is low, the fault tolerance rate of the system is greatly reduced, and the later maintenance cost of the system is increased.

[0004] In summary, there are major problems at present: the series converters in the prior art cannot meet the application requirements of low turn-on loss, low switching loss, low cost, high overload and short-circuit capability, and high frequency at the same time, and the existing series converters The converter does not have fault operation capability, and the failure of a certain power device in the converter will cause the entire converter to stop running, reducing the reliability of the system, increasing maintenance costs and causing a certain degree of economic loss

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