Abstract: Known method suitable for implementation in a computer program product for VCT closed-loop control system generally includes an integrator to eliminate the steady state error. A novel method suitable for implementation in a computer program product includes a set point filter as well to reduce the closed-loop control overshoot. Low cam torque frequency can reduce the stability of a closed-loop control system when combined with the integral action, and it can also compromise the effect of set point filter. This novel method addresses these two issues by identifying the cam torque direction and pausing control updating when there is no torque available at the desired direction.

Abstract: In a VCT system, a method uses a controller to automatically determine a state of a phaser based on an identifier. The identifier identifies a filtered signal of the crank shaft and cam shaft and uses the same to identify the phaser state. A reset signal is generated by the identifier to reset the VCT system, specifically to reset a control law whereby the unnecessary information retained by the VCT system is cleared. Therefore, the controller is able to promptly and accurately determine the phaser position and state.

Abstract: In a VCT system, a method uses a controller to automatically determine a state of a phaser based on an identifier. The identifier identifies a filtered signal of the crank shaft and cam shaft and uses the same to identify the phaser state. A reset signal is generated by the identifier to reset the VCT system, specifically to reset a control law whereby the unnecessary information retained by the VCT system is cleared. Therefore, the controller is able to promptly and accurately determine the phaser position and state.