METHOD AND SYSTEM FOR CONTROLLING A POWER INVERTER IN ELECTRIC DRIVES OF VEHICLES WITH TWO-MODE TRANSMISSIONS
First Claim
1. A method for controlling a power inverter coupled to an electric motor in an electric drive system of an automobile, wherein the electric drive system includes a prime mover power source, a two-mode, compound-split, electro-mechanical transmission coupled to the prime mover power source, the transmission comprising a first motor and a second motor, wherein the power inverter is coupled to the first and second motors, the method comprising:
- responsive to a commanded torque of the first motor being below a first torque level, controlling the power inverter to set a switching frequency of the power inverter at a first set frequency; and
responsive to the commanded torque of the first motor being between the first torque level and a second torque level, controlling the power inverter to determine the switching frequency of the power inverter as a function of the commanded torque of the electric motor while maintaining the switching frequency above a dynamic frequency limit.
12 Assignments
0 Petitions
Accused Products
Abstract
Methods and systems for controlling a power inverter in automobiles utilizing two-mode transmissions are provided. The various embodiments control the power inverter by, responsive to a commanded torque of the electric motor being below a first torque level, controlling the power inverter to set a switching frequency of the power inverter at a first set frequency; and, responsive to the commanded torque of the electric motor being between the first torque level and a second torque level, controlling the power inverter to determine the switching frequency of the power inverter as a function of the commanded torque of the electric motor while maintaining the switching frequency above a dynamic frequency limit. The method reduces switching frequencies in the inverter at high commanded torques, while maintaining the switching frequencies above dynamic frequency limit that provides effective control over the motor.
-
Citations
17 Claims
-
1. A method for controlling a power inverter coupled to an electric motor in an electric drive system of an automobile, wherein the electric drive system includes a prime mover power source, a two-mode, compound-split, electro-mechanical transmission coupled to the prime mover power source, the transmission comprising a first motor and a second motor, wherein the power inverter is coupled to the first and second motors, the method comprising:
-
responsive to a commanded torque of the first motor being below a first torque level, controlling the power inverter to set a switching frequency of the power inverter at a first set frequency; and responsive to the commanded torque of the first motor being between the first torque level and a second torque level, controlling the power inverter to determine the switching frequency of the power inverter as a function of the commanded torque of the electric motor while maintaining the switching frequency above a dynamic frequency limit. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. An automotive electric drive system comprising:
-
a prime mover power source; a two-mode, compound-split, electro-mechanical transmission coupled to the prime mover power source, the transmission comprising first and second motors; a power inverter coupled to the first and second motors; and a processor coupled to the first and second motors and the power inverter, the processor being configured to; responsive to a commanded torque of the first motor being below a first torque level, provide a signal controlling the power inverter to set a switching frequency of the power inverter at a first set frequency; responsive to the commanded torque of the first motor being between the first torque level and a second torque level, provide a signal controlling the power inverter to determine the switching frequency of the power inverter as a function of the commanded torque of the electric motor while maintaining the switching frequency above a dynamic frequency limit. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15)
-
-
16. An automotive drive system comprising:
-
a prime mover power source; a two-mode, compound-split, electro-mechanical transmission coupled to the prime mover power source, the transmission comprising; an input member to receive power from the prime mover; an output member to deliver power from the transmission; first and second motors being coaxially aligned; first, second, and third coaxially aligned planetary gear arrangements, each planetary gear arrangement utilizing first, second and third gear members, the first and second motors being coaxially aligned with the three planetary gear arrangements, at least one of the first, second, and third gear members in the first or second planetary gear arrangement being connected to the first motor, and another one of the first, second, and third gear members in the second and third planetary gear arrangements being connected to the second motor, one of the gear members of the first planetary gear arrangement being continuously connected to the input member; a first torque-transmitting mechanism to selectively connect one of the gear members associated with each of the planetary gear arrangements to each other and to the output member; a second torque-transmitting mechanism to selectively connect one of the gear members of the third planetary gear set with ground; a third torque-transmitting mechanism to selectively connect one of the gear members of the second planetary gear set with another of the gear members of the second planetary gear set; a first interconnecting member continuously connecting one of the members of the first planetary gear set with one of the members of the second planetary gear set; and a second interconnecting member continuously connecting one of the members of the second planetary gear set with one of the members of the third planetary gear set; a power inverter coupled to the first and second motors; an energy storage device coupled to the power inverter; and a processor coupled to the first and second motors and the power inverter, the processor being configured to; responsive to a commanded torque of the first motor being below a first torque level, provide a signal controlling the power inverter to set a switching frequency of the power inverter at a first set frequency; responsive to the commanded torque of the first motor being between the first torque level and a second torque level, provide a signal controlling the power inverter to determine the switching frequency of the power inverter as a function of the commanded torque of the electric motor while maintaining the switching frequency above a dynamic frequency limit;
wherein the function of the commanded torque is selected to decrease switching frequency as the commanded torque increases, and wherein the dynamic frequency limit determined by;responsive to the motor speed of the first motor being between a first speed level and a second speed level, determining the dynamic frequency limit as a function of the motor speed to maintain set pulse ratio of motor switching frequency to motor speed; responsive to the motor speed being below the first speed level, determining the dynamic frequency limit to set the dynamic frequency limit at a second set frequency; and responsive to the motor speed being above second speed level, determining the dynamic frequency limit to set the dynamic frequency limit at the first set frequency. - View Dependent Claims (17)
-
Specification