Hybrid Powertrain Controller Integral Torque Reset
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hybrid powertrains face challenges in maintaining smooth closed-loop control during transitional vehicle events, such as hybrid state transitions or control gain reduction events, leading to driver-perceptible speed oscillations due to discontinuous control torque and erroneous control history carryover.
Innovation Solution
A controller resets the integral torque term for the target value in a specific manner to ensure continuous total control torque, regardless of the torque actuator used, using proportional-integral (PI) control logic, and transforms virtual actuators to physical actuators to maintain smooth torque transitions during events like hybrid range state transitions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If PI or PID control logic is used to control multiple torque actuators in a closed loop, then the desired target value (engine or clutch rotational torque, speed, or driveline damping) can be achieved, but smooth closed-loop control becomes difficult to maintain during transitional vehicle events such as hybrid state transitions or control gain reduction events
Solution Approach 1:
The controller detects the predetermined vehicle event (hybrid state transition or control gain reduction event) in advance and proactively resets the integral control torque term for the target value during the transition. This preliminary action prevents discontinuous control torque and erroneous control history carryover, ensuring smooth closed-loop control is maintained throughout the transitional event without disrupting the desired target value achievement
2Stability of the object's composition
If the integral control torque term is not reset during hybrid state transitions, then control history is preserved, but driver-perceptible speed oscillations or bumps occur due to discontinuous closed-loop control torque
Solution Approach 1:
The patent converts the potentially harmful effect of resetting the integral control torque term (which could cause control discontinuity) into a beneficial outcome by strategically timing the reset during the predetermined vehicle event. The reset eliminates erroneous control history carryover and discontinuous control torque that cause driver-perceptible speed oscillations, while the controller maintains the total control torque for the target value through the execution of the event, thus transforming a potentially harmful action into a solution that ensures control smoothness
Data Source
AI summary
A powertrain includes a controller and gear sets, clutches, rotatable members, and torque actuators, e.g., an engine and one or more motor/generator units. Each torque actuator outputs a total control torque. The total control torque from a given actuator is used to achieve a target value, which is a torque value of a member of one of the gear sets, clutches, or rotatable members. The controller includes proportional-integral (PI) control logic. The total control torque is the sum of proportional and integral torque terms from the PI control logic. The controller detects a predetermined vehicle event, for instance a change in a hybrid range state or a control gain reduction event, and then automatically resets the integral control torque term(s) for the physical target value during the requested vehicle event to thereby maintain the total control torque for the same target value through the execution of the predetermined vehicle event.