On-vehicle motor control device
AssigneeDenso Corporation
InventorJirou Hayashi
Life of this patent
Estimating the term…
Abstract
An on-vehicle motor control device includes a power switching circuit disposed on a circuit board to supply current from a battery to a motor, a microcomputer disposed on the same circuit board that controls the power switching circuit in a PWM control mode to minimize the difference between the current supplied to the motor and a preset current. The microcomputer decreases the preset current when the battery voltage is higher than an upper limit or when both the battery voltage and the voltage of the ignition key signal are higher than respective upper limits.
Claims8
A motor control device connected to a battery, said motor control device comprising:
- a circuit board;
- a power switching means, disposed on said circuit board for supplying current from the battery to a motor mounted in a vehicle;
- a control circuit, including a microcomputer disposed near said power switching means, for controlling said power switching means in a PWM control mode so that an amount of the current supplied to the motor can be equal to a preset amount of current,
- wherein said microcomputer decreases the preset amount of current to an amount to prevent said microcomputer from overheating due to Joule heat of said power switching means when the voltage of the battery is higher than an upper limit.
A motor control device connected to a battery and an ignition key signal detecting circuit, said motor control device comprising:
- a circuit board;
- a power switching means, disposed on said circuit board for supplying current from the battery to a motor mounted in a vehicle;
- a microcomputer, disposed on said circuit board near said lower switching means, for controlling said power switching means in a PWM control mode so that an amount of the current supplied to the motor can be equal to a preset amount of current,
- wherein said microcomputer decreases the preset amount of current to control Joule heat of said power switching means thereby protecting said microcomputer from overheating when both the battery voltage and the voltage of the ignition key signal are higher than respective upper limits.
Dependencies are inferred from the claim text.