ROBUST INVERTER TOPOLOGY

An inverter system includes an inverter controller (105, 107) and at least one surge protection device (100a, 100b). The inverter controller is configured to operate multiple switches (102) to provide an alternating current to an output. The at least one surge protection device is configured to limit a voltage on a direct current link of the inverter. The at least one surge protection device includes a variable resistance component (90a, 90b) coupled to the direct current link of the inverter, a sensing resistor (92a, 92b) selectively connected in parallel to the variable resistance component by a switching component(93a, 93b), a detection device (94a, 94b) configured to measure a parameter of the sensing resistor, and a control circuit including failure sensing logic (95) configured to detect a failure in the variable resistance component in response to information from the variable resistance component and information from the detection device for the parameter of the sensing resistor.Fig. 9