Shindengen Electric Manufacturing Company Limited

Tomomi Harada

Tatsuya Arai

A brushless motor control apparatus calculates the number of rotations of an engine based on a cycle of zero-cross points of the phase voltage induced to a sub-coil of a three-phase brushless motor. When the number of rotation of the engine is smaller than the first number of rotations, before it becomes impossible to detect the zero-cross points, the control state of the three-phase brushless motor is changed from the state of phase control by a phase control regulator unit with respect to the AC output voltages to the state of interphase short circuit of motor coils by a short regulator unit. When the number of rotations of the engine exceeds the first number of rotations and the phase voltage becomes the voltage level such that the zero-cross points can be detected, the control state is changed again to the state of phase control by the phase control regulator unit.

Brushless motor control apparatus and brushless motor control method

A engine control unit comprises: a three-phase bridge circuit that has a first end connected to the first end of the first load and a second end connected to a ground, the three-phase bridge circuit performing commutation control on an alternating-current power supplied from the motor generator or driving the motor generator; a DC-DC converter connected between the first end of the three-phase bridge circuit and a second end of the control switch; a diode that has an anode connected to the battery connecting terminal and a cathode connected to the second end of the control switch; a voltage detecting circuit that detects a voltage of the battery connecting terminal; a first switch element connected between a second end of the coil and the ground; a second switch element connected between a second end of the first load and the ground; and a control circuit.

Vehicle power supply system, engine control unit, and power supply method

A brushless motor control device according to the present invention drives a brushless motor including a stator having coils of three phases U, V, and W and a neutral line, and a sub coil provided in any one phase of the phases U, V, and W, for detecting a voltage induced in the coil of the one phase, and the brushless motor control device carries out a conduction control function, for the respective phase coils of the brushless motor, that performs a 120&#xb0; conduction when a rotation speed of the brushless motor is lower than or equal to a predetermined rotation speed, and that performs a 180&#xb0; conduction when the rotation speed is higher than or equal to the predetermined rotation speed, and the brushless motor control device includes a motor control unit that controls the brushless motor based on information of the rotor stop position when activating the brushless motor, controls the brushless motor based on the first rotor position information when in the 120&#xb0; conduction, and controls the brushless motor based on the second rotor position information when in the 180&#xb0; conduction.

Brushless motor control device and brushless motor control method

A brushless motor control system according to the present invention detects a rotor stop position when activating the brushless motor including a stator having coils of three phases U, V, and W, and controls a phase voltage for energizing the coils of the respective phases U, V, and W, and the brushless motor includes the stator having coils of phases U, V, and W of N (N&#x2267;2) poles, in which any one phase coil among the coils of the phases U, V, and W is removed in one of the N poles, and the brushless motor control system includes: a current rise detecting circuit that, when the brushless motor is in a stop state, sequentially selects coils of two phases from the coils of the respective phases U, V, and W, applies a predetermined direct current voltage between the selected coils of the two phases, and detects a value of an electric current flowing to the selected coils of the two phases; and a rotor stop position detecting unit that determines a rotor stop position of the brushless motor based on information of the value of the electric current flowing to the respective phase coils which is detected by the current rise detecting circuit.

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Hanno, Japan

Tomomi Harada