| CPC H02P 27/06 (2013.01) [H02P 23/00 (2013.01)] | 8 Claims |
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1. A rotating electrical machine control system that controls drive of a rotating electrical machine having open-end windings of a plurality of phases that are independent of each other, the rotating electrical machine control system comprising:
a first inverter connected to a one-end side of the open-end windings;
a second inverter connected to an other-end side of the open-end windings;
a first direct-current power supply to which the first inverter is connected;
a second direct-current power supply to which the second inverter is connected;
a first smoothing capacitor connected in parallel to the first direct-current power supply;
a second smoothing capacitor connected in parallel to the second direct-current power supply;
a first contactor that establishes and cuts off an electrical connection between the first inverter and the first smoothing capacitor, and the first direct-current power supply;
a second contactor that establishes and cuts off an electrical connection between the second inverter and the second smoothing capacitor, and the second direct-current power supply; and
a control part that controls each of the first contactor and the second contactor and can control the first inverter and the second inverter independently of each other,
wherein
in the first inverter and the second inverter, an arm for one alternating-current phase includes a series circuit of an upper-stage-side switching element and a lower-stage-side switching element,
the control part can control each of the first inverter and the second inverter by active short-circuit control that brings all of the upper-stage-side switching elements into off state and brings all of the lower-stage-side switching elements into on state, or brings all of the upper-stage-side switching elements into on state and brings all of the lower-stage-side switching elements into off state, and by shutdown control that brings all switching elements of a plurality of phases into off state, and
using a first upper limit voltage set to a value larger than a voltage fluctuation range of the first direct-current power supply, a first lower limit voltage set to a value smaller than a voltage fluctuation range of the first direct-current power supply, a second upper limit voltage set to a value larger than a voltage fluctuation range of the second direct-current power supply, and a second lower limit voltage set to a value smaller than a voltage fluctuation range of the second direct-current power supply,
the control part
determines that the first contactor is in an open state, when a voltage at both ends of the first smoothing capacitor is higher than the first upper limit voltage or lower than the first lower limit voltage, and a current flowing through the first direct-current power supply is less than or equal to a first lower limit current defined in advance;
determines that the second contactor is in an open state, when a voltage at both ends of the second smoothing capacitor is higher than the second upper limit voltage or lower than the second lower limit voltage, and a current flowing through the second direct-current power supply is less than or equal to a second lower limit current defined in advance;
considers one of contactors that is determined to be in an open state a failed contactor and considers an other one of the contactors a normal contactor, the contactors being the first contactor and the second contactor;
controls both the first inverter and the second inverter by shutdown control and brings both the first contactor and the second contactor into an open state, in a state in which a rotational speed of the rotating electrical machine is greater than or equal to a speed threshold value defined in advance;
after a rotational speed of the rotating electrical machine reaches less than the speed threshold value, controls a failure-side inverter by the active short-circuit control and maintains the normal contactor in an open state, and drives a normal-side inverter using discharge torque of a normal-side smoothing capacitor, the failure-side inverter being an inverter connected to the failed contactor, the normal-side inverter being an inverter connected to the normal contactor, and the normal-side smoothing capacitor being a smoothing capacitor connected to the normal-side inverter; and
after a rise in a voltage at both ends of the normal-side smoothing capacitor is eliminated, controls the normal contactor to a closed state and controls drive of the rotating electrical machine by the normal-side inverter.
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