초록 ▼

A method for simultaneous testing of individual components in multiple three phase inverters, each connected to a common source of direct current electric power and being coupled to supply power to a respective one of a plurality of three phase loads, involves the steps of monitoring the voltage app

A method for simultaneous testing of individual components in multiple three phase inverters, each connected to a common source of direct current electric power and being coupled to supply power to a respective one of a plurality of three phase loads, involves the steps of monitoring the voltage applied to the inverters and the current at each output phase terminal while gating each switching device in each inverter momentarily into conduction in sequence from a first switching device in a first phase to a last switching device in a third phase until an input voltage drop or an output current is detected. In response to a detected voltage drop, the sequence of gating is interrupted and advanced forward to the next occurring phase. If phase current is detected in any phase during gating, the inverter generating the current is disabled. The gating sequence is modified after detection of a voltage drop to initiate subsequent gating at a phase following the phase at which the voltage drop was detected to prevent inadvertent gating of short-circuited phases.

대표청구항 ▼

[ What is claimed is:] [1.] A method for simultaneously testing a plurality of inverters for failure of individual components said inverters being connected to a common source of direct current electric power, each of the inverters comprising at least three phases with each phase comprising at least

[ What is claimed is:] [1.] A method for simultaneously testing a plurality of inverters for failure of individual components said inverters being connected to a common source of direct current electric power, each of the inverters comprising at least three phases with each phase comprising at least two switching devices serially connected between a relatively positive voltage bus and a relatively negative voltage bus, each of the inverters being coupled to supply power to a respective one of a plurality of three phase loads via a connection from respective junctions mediate each pair of switching devices to a corresponding phase terminal of the respective load, comprising simultaneously testing said plurality of inverters by:monitoring voltage between the positive and negative voltage busses and monitoring current at each phase terminal of each load;gating each switching device in each inverter momentarily into conduction in sequence from a first switching device in a first phase to a second switching device in a third phase until detection of a voltage drop or a load current;interrupting, in response to a detected voltage drop, the sequence of gating and advancing the step of gating to the next occurring phase; andinhibiting operation of any inverter in which phase current is detected in any phase during the step of gating.