Fault handling of inverter driven PM motor drives
View Patent ↗An apparatus includes a multi-phase inverter, a fault detector to indicate a detection of a fault, a sensor to provide a speed signal indicative of whether a speed of a PM motor is greater than a transition speed, and a controller. The controller is operable to apply either an open-circuit response or a short-circuit response to the multi-phase inverter. The open-circuit response is applied when the speed of the PM motor is greater less than the transition speed and a fault is detected. The short-circuit response is applied when the speed of the PM motor is less greater than the transition speed and the fault is detected. The transition speed is either a fixed predetermined speed or an adjusted predetermined speed.
1. A method for controlling a multi-phase inverter of a PM motor comprising:
detecting a fault: ;
sensing whether a speed signal indicates that a speed of the PM motor is greater than a transition speed;
applying an open-circuit response when the speed of the PM motor is greater less than the transition speed when the fault is detected; and
applying a short-circuit response when the sped of the PM motor is less greater than the transition speed when the fault is detected,
wherein the transition speed is one of a fixed predetermined speed and an adjusted predetermined speed.
2. A method according to claim 1 , wherein the applying the open-circuit response includes controlling all switches in the multi-phase inverter drive to be open.
3. A method according to claim 1 , wherein the applying the short-circuit response includes controlling selected switches in the multi-phase inverter drive to connect all phases of the multi-phase inverter to a single bus and controlling all other switches in the multi-phase inverter drive to be open.
4. A method according to claim 1 , wherein the transition speed is the fixed predetermined speed and is defined based on parameters characteristic of the PM motor.
5. A method according to claim 1 , wherein the transition speed is the adjusted predetermined speed and is defined based on parameters characteristic of the PM motor adjusted according to at least one of a temperature of the PM motor and a voltage of a voltage source.
6. An apparatus comprising:
a multi-phase inverter;
a fault detector to indicate a detection of a fault;
a sensor to provide a speed signal indicative of whether a speed of a PM motor is greater than a transition speed; and
a controller operable to apply an open-circuit response to the multi-phase inverter when the speed of the PM motor is greater less than the transition speed and a fault is detected, and additionally operable to apply a short-circuit response to the multi-phase inverter when the speed of the PM motor is less greater than the transition speed and the fault is detected, wherein the transition speed is one of a fixed predetermined speed and an adjusted predetermined speed.
7. An apparatus according to claim 6 , wherein the application of the open-circuit response by the controller controls all switches in the multi-phase inverter to be open.
8. An apparatus according to claim 6 , wherein the application of the short-circuit response by the controller controls selected switches in the multi-phase inverter to connect all phases of the multi-phase inverter to a single bus and controls all other switches in the multi-phase inverter to be open.
9. An apparatus according to claim 6 , wherein the transition speed is the fixed predetermined speed and is defined based on parameters characteristic of the PM motor.
10. An apparatus according to claim 6 , wherein the transition speed is the adjusted predetermined speed and is defined based on parameters characteristic of the PM motor adjusted according to at least one of a temperature of the PM motor and a voltage of a voltage source.
11. A machine-readable medium comprising sets of instructions operable in a controller to cause the controller to perform operations comprising:
applying an open-circuit response to a multi-phase inverter when a speed signal from a sensor indicates that a speed of a PM motor is greater less than a transition speed when a fault is detected; and
applying a short-circuit response to the multi-phase inverter when the speed signal indicates that the speed of the PM motor is less greater than the transition speed when the fault is detected,
wherein the transition speed is one of a fixed predetermined speed and an adjusted predetermined speed.
12. A machine-readable medium according to claim 11 , wherein the operation of applying the open-circuit response includes controlling all switches in the multi-phase inverter drive to be open.
13. A machine-readable medium according to claim 11 , wherries the operation of applying the short-circuit response includes controlling selected switches in the multi-phase inverter drive to connect all phases of the multi-phase inverter to a single bus and controlling all other switches in the multi-phase inverter drive to be open.
14. A machine-readable medium according to claim 11 , wherein the transition speed is the fixed predetermined speed and is defined based on parameters characteristic of the PM motor.
15. A machine-readable medium according to claim 11 , wherein the transition speed is the adjusted predetermined speed and is defined based on parameters characteristic of the PM motor adjusted according to at least one of a temperature of the PM motor and a voltage of a voltage source.