Control device

Abstract

The present invention provided a controller which capable of avoiding an overload state of an actuator without using a sensor and so forth. An ECU (2) of the controller (1) calculates a lift control input U_Liftin into a variable valve lift mechanism (50) according to an algorithm of formulae ((2) to (5)) so that the valve lift Liftin follows up a target valve lift Liftin_cmd, integrates the product of the value Imot of the current flowing through the variable valve lift mechanism (50) and the sampling period Stime to calculate the integrated value SImot. If SImot=SImot_J1, two parameters pole_f_lf, pole_lf are set to predetermined failure values pole_f_lf_J1, pole_lf_J1, respectively, at which the lift control input U_Liftin is smaller than that of when SImot<SImot_J1.

Description

technical field [0001] The present invention relates to a control device that controls a control amount by an actuator that converts supplied electric power into driving force. Background technique [0002] Conventionally, as a control device that controls an assist torque for assisting a driver's steering force through an electric power steering (electric power steering) as an actuator, a device described in Patent Document 1 is known. . The electric power steering system includes an electric motor that generates assist torque, and the control device includes a thermistor that detects the temperature of the electric motor, a vehicle speed sensor that detects the vehicle speed, and the like. [0003] This control device controls the assist torque by determining a voltage applied to the motor based on the temperature of the motor detected by the thermistor and the vehicle speed detected by the vehicle speed sensor, thereby controlling the assist torque. First, the temperatu...

AI Technical Summary

Problems solved by technology

[0009] According to the control device of the above-mentioned Patent Document 1, a thermistor for detecting the temperature of the motor is required, so the manufacturing cost increases accordingly, and when the thermistor fails, the motor is overloaded, and motor failure such as burning may occur.

In addition, it is difficult to install the thermistor for temperature detection on the rotating part of the motor in terms of design, so the result is to detect the temperature at a position that has a correlation with the coil temperature of the motor. As a result, a temperature measurement delay occurs, and the motor is overloaded. Status checkout may be delayed

[0010] In addition, in the control device of the aforementioned Patent Document 2, the square value of the current flowing through the motor is used when calculating the estimated temperature, so the degree of change in the estimated temperature increases as the current value changes.

Therefore, in the judgment to avoid overheating of the motor, it is difficult to properly set the judgment value compared with the estimated temperature, which may lead to erroneous judgment.

In addition, an ambient temperature sensor is required, so the manufacturing cost increases accordingly, and when the ambient temperature sensor fails, the temperature of the motor cannot be properly estimated

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