【摘要】 由于电流滞环控制下的逆变器的输出电压波形不具备规律性,基于电压进行的故障诊断难以获得可靠的结果,该文提出一种在电流滞环控制下逆变器功率管发生开路故障的基于电流的在线诊断方法及容错控制结构。在建立相电流数学模型的基础上,基于电流滞环控制的三相桥式逆变电路仿真模型对不同工作状态下的输出电流波形进行了分析,通过分析发现,在故障时会出现输出电流畸变及输出电流追踪指令电流的方向失效两个明显故障特征,利用其可以在极短时间内对功率管开路故障进行诊断并定位,在获得故障发生准确位置后对其进行容错控制结构的投切。该诊断方法用时短、简单易行、不需要获取系统控制信号及装设额外传感器,容错控制结构成本较低,安装方便,容错效果良好。最后通过dSPACE实验平台对该文所提诊断方法及容错控制结构的有效性、可靠性及局限性进行了验证与分析。更多还原

【Abstract】 Because of the irregularities of the output voltage waveform of inverter with hysteresis current control, the fault diagnosis based on voltage is difficult to obtain reliable results. In this paper, an on-line current-based fault diagnosis method and a fault-tolerant structure for the power-switch open-circuit fault of inverter with hysteresis current control are proposed. Based on the establishment of phase-current mathematical model and three-phase bridge inverter circuit with hysteresis current control, the output current waveform of different working states is analyzed. Analysis shows that there are two obvious fault characteristics in the event of a fault. These two fault characteristics are the output current and the direction of output current tracking reference current, respectively. These can be used to quickly diagnose and locate the open circuit fault of power tubes. Fault-tolerant control can be carried out after obtaining the exact location of the fault. The proposed diagnosis method is simple and easy to apply, it does not require system control signals or additional sensors, and has a short diagnosis time. Fault-tolerant structure has controllable cost, convenient installation and good fault-tolerant effect. The validity, reliability and limitations of the proposed diagnosis method and fault-tolerant structure are verified and analyzed by dSPACE hardware-in-the-loop experiment platform.更多还原