Control apparatus and shift-by-wire system using the same

Patent metadata

Field	Value
Publication number	US-9325275-B2
Application number	US-201414559250-A
Country	US
Kind code	B2
Filing date	Dec 3, 2014
Priority date	Dec 6, 2013
Publication date	Apr 26, 2016
Grant date	Apr 26, 2016

Abstract

A current limiting circuit restricts electric currents flowing through windings and MOSs such that an average of a current value of the electric currents detected by a current detection circuit is within a predetermined value span. An MPU functions as a reference position learning controller that performs a reference position learning control to restrict the electric currents that flow through the windings and the MOSs using the current limiting circuit while rotating a motor until a detent plate stops at a limit position of a working span, to thereby learn the reference position of the motor. An anomaly detection section of the MPU functions as an anomaly detection controller to detect an anomaly in the current limiting circuit based on the current value detected by the current detection circuit during the reference position learning control.

First claim

What is claimed is:

1. A control apparatus controlling a motor that includes windings with a plurality of phases, the motor rotating on electric power from a power source to rotate and drive a driving target,
the control apparatus comprising:
a plurality of switching devices provided to correspond to the respective phases of the windings, each switching device permitting current application to corresponding windings by performing ON operation and shutting down the current application to the corresponding windings by performing OFF operation;
a drive controller that controls driving of the motor by controlling the ON operation or the OFF operation of each switching device;
a current detection circuit that detects a current value of electric currents flowing through the windings and the switching devices;
a current limiting circuit that restricts the electric currents flowing through the windings and the switching devices so that an average of the current value detected by the current detection circuit is within a predetermined value span;
a reference position learning controller that performs a reference position learning control to rotate the motor until the driving target stops at a limit position of a working span while restricting the electric currents flowing through the windings and the switching devices by using the current limiting circuit, to learn a reference position of the motor; and
an anomaly detection controller that detects an anomaly in the current limiting circuit based on the current value detected by the current detection circuit during the reference position learning control performed by the reference position learning controller.

2. The control apparatus according to claim 1 , wherein
the anomaly detection controller detects the anomaly in the current limiting circuit based on the current value detected by the current detection circuit after a predetermined time period elapses since rotation of the motor stops due to the driving target stopping at a limit position of a working span.

3. The control apparatus according to claim 1 , wherein
the anomaly detection controller
determines that the current limiting circuit is normal when the average of the current value detected by the current detection circuit is within a predetermined value span, and
determines that the current limiting circuit is anomalous when the average of the current value detected by the current detection circuit is outside of the predetermined value span.

4. A shift-by-wire system in a vehicle, comprising:
the control apparatus according to claim 1 ,
the motor controlled by the control apparatus; and
the driving target that switches a shift range of the vehicle by being rotated and driven by the motor.

Assignees

• Denso Corp

Inventors

• Yamada Jun

Classifications

• F16H2061/247

  Detents for range selectors · CPC title

• H02P29/027 Primary

  the fault being an over-current · CPC title