机载矩阵变换器可靠性关键技术研究

Based on the Aircraft Electric Actuator System, this project is going to make a deep research on applicative solutions of SiC Matrix Converters(MC) with high reliability and its fault diagnosis and fault-tolerant management technologies. By investigating the behaviors of the typical MC fault modes and the influencing factors, a real-time open-fault diagnosis method, which has good universality and reliability, will be proposed based on the signals of MC fundamental control, with no additional hardwares. Safe ways to manage short-circuit faults will be deeply investigated. Fault-tolerant circuit configurations and their control method will also be studied for MC-motor drive system. An improved SVM modulation method will be proposed to deal with imbalanced supply voltages and imbalanced output conditions. The reasons of the harmonic current and the motor torque pulsation during the fault-tolerant operation of the MC-motor system will be thoroughy inspected. Then the ways to compensate the harmonic current and the motor torque pulsation and the ways to improve the output capability will be explored. In the end, a laboratory prototype based on SiC devices will be developed to derive the key technologies of the MC with high power density and high reliability. And the problems that would be met in the aeraospace variant-frequency power system application of MC will also be answered.

以飞机电力作动系统为应用背景，研究高可靠性SiC矩阵变换器(MC)技术及其故障诊断和容错运行解决方案。主要研究：⑴分析MC典型故障模式的行为特征及影响因素，提出一种快速可靠的开路故障诊断方法，无需额外增加硬件，仅通过矩阵变换器正常控制所需采集的输出电流信号实现，且通用性强，不依赖于特定调制策略和负载性质，不依赖于输入电源特性；⑵研究适合矩阵变换器的短路故障应对策略，探索短路故障隔离动作执行期间，不间断容错运行的可能性和方法，给出两正常相的安全管理方法；⑶研究MC电机驱动系统容错电路及控制方法，提出不对称输入、不对称输出时MC调制策略，谐波和电机转矩脉动补偿方法，以及提高容错运行输出能力的方法；⑷基于SiC JFET，研制MC-PMSM电力作动系统实验平台，重点解决高可靠性MC技术及在航空宽变频交流电源环境中的应用解决方案。

矩阵变换器被认为是最具潜力的航空功率变换器之一。可靠性是航空机载设备的重要指标之一。本项目从故障诊断、容错运行、可靠性设计三个方面对矩阵变换器的可靠性进行了深入研究。首先，本项目基于箝位电路电流（MC输出电流与负载电流之间的差值），提出开路故障相的辨识方法；将此电流差值与故障相6个开关控制信号结合，提出一种快速的基于调制电流差值法的开路故障诊断策略；短路故障是一种非预期、不可控的电路连接，不及时隔离，严重影响矩阵变换器负载、电源和其他负载的安全，本项目研究了短路隔离期间，负载和电源的行为表现，揭示短路故障的快速隔离是保障航空电源系统正常运行的根本；基于多路能量的综合利用提出一种快速的短路故障隔离策略，可将短路隔离时间缩短至传统方法的10%；研究了开路故障、短路故障隔离后的容错运行策略及对电源系统的要求；采用SiC JFET器件，深入研究了双向开关和矩阵变换器的可靠性实现方法。