In a hybrid vehicle, noise occurrence caused in a rectangular wave control of a motor is restricted when a motor running mode is selected with a converter boosting limit applied. A motor controller for a hybrid vehicle mounted with an internal combustion engine and a motor as power sources is provided. The motor controller includes a converter capable of boosting a voltage supplied from a power supply device; an inverter which converts an output voltage of the converter to an AC voltage and applies the AC voltage to the motor; and a control unit which controls the inverter to drive the motor by switching between two or more control modes. When a running mode to drive the vehicle by a motor power alone is selected with a boost limit applied to the output voltage of the converter and when the motor is driven in a rectangular wave control mode or an overmodulation PWM control mode, the control unit raises the output voltage of the converter higher than a boost limit value and controls the inverter such that the control mode is switched to drive the motor in a sinusoidal PWM control mode.

The present invention discloses a modulation method for a three-phase multilevel converter. The modulation method comprises the following steps: generating first three-phase sinusoidal modulated wave signals by a control loop in the three-phase multilevel converter; generating second three-phase modulated wave signals by processing the first three-phase sinusoidal modulated wave signals, wherein in proximity to peak values of a line voltage of the second three-phase modulated wave signals, absolute values of any two phases are unequal; generating PWM pulse signals based on the second three-phase modulated wave signals; and generating driving signals for respective power units in the three-phase multilevel converter based on the PWM pulse signals.

In a motor drive apparatus, the brushless motor has a three-phase motor structure, the Hall sensor detects a magnetic flux change signal in an operation of the brushless motor, the control unit obtains a rotor rotation number of the brushless motor (11) based on the magnetic flux change signal, calculates a predetermined electric angle even when the rotor rotation number is changed, and causes the gate driver to output a PWM signal by which a power distribution timing to each phase of the brushless motor is switched at the predetermined electric angle, and the inverter sinusoidally changes and supplies a voltage supply to a stator coil of the brushless motor based on the PWM signal.

The circuit for controlling a rotating three-phase motor of the type having three interconnected motor coils each corresponding to one of three phases employs a plurality of switching circuit components, each connected to the motor to supply current to one of the coils. A signal generator circuit produces in synchronism with the rotation of the motor a variable duty cycle pulse-width modulated signal for each of the switching circuit components. A logic gating circuit is coupled to the signal generator circuit and to the switching components. The logic gating circuit is operative to cause the switching circuit components to selectively place pairs of motor coils in current conducting states such that when the variable duty cycle pulse-width modulated signals are each concurrently in the same logical on-off state, the logic gating circuit supplies a logical off state to each of the switching circuit components.

A pulse generation unit is configured to output pulse signals for driving the stepping motor. A control unit is configured to perform acceleration control or deceleration control of the stepping motor via the pulse generation unit. The control unit is configured to calculate a number of the pulse signals to be output from the pulse generation unit to the stepping motor when accelerating or decelerating the stepping motor at constant acceleration in the acceleration control or the deceleration control based on an initial speed of the stepping motor when the acceleration control or the deceleration control starts, a target rotation speed, and time from start control of the stepping motor to time when the stepping motor reaches the target rotation speed, and change a rotation speed of the stepping motor in the acceleration control or the deceleration control along a sinusoidal waveform.

An electric motor control device includes a drive waveform generating unit configured to generate a drive waveform (a sine wave or a pseudo-trapezoidal wave) to an electric motor. A plurality of photo interrupters detect a rotational phase of an electric motor, and a information of rotational speed is detected by an encoder circuit based on a detected signal of the rotational phase of the electric motor. The control unit controls the drive waveform generating unit on the basis of detection information of the rotational phase of the electric motor and performs control so that a phase relationship between the rotational phase of the electric motor and the phase of the drive waveform is kept constant. Furthermore, the control unit sets an amplitude value of the drive waveform generated by the drive waveform generating unit in accordance with a difference between a target speed and the detected information of rotational speed and performs speed control so that a speed of the electric motor is kept constant. The control unit calculates an amplitude setting value with which correction for suppressing non-linearity is performed in a region in which an amplitude setting value of the drive waveform and actual work given to the electric motor is non-linear and controls the speed.

The circuit for controlling a rotating three-phase motor of the type having three interconnected motor coils each corresponding to one of three phases employs a plurality of switching circuit components, each connected to the motor to supply current to one of the coils. A signal generator circuit produces in synchronism with the rotation of the motor a variable duty cycle pulse-width modulated signal for each of the switching circuit components. A logic gating circuit is coupled to the signal generator circuit and to the switching components. The logic gating circuit is operative to cause the switching circuit components to selectively place pairs of motor coils in current conducting states such that when the variable duty cycle pulse-width modulated signals are each concurrently in the same logical on-off state, the logic gating circuit supplies a logical off state to each of the switching circuit components.

In a method of operating an electric motor, a pulse-width-modulated basic signal having a pulse width modulation frequency is generated for an electric variable of the electric motor. A control unit generates for the electric variable a sinusoidal additional signal at a sinusoidal frequency in an acoustically audible frequency range, and adds the basic signal and the additional signal to form an acoustic signal for the electric variable. The electric variable with the acoustic signal can be made available to the electric motor.

The method of controlling a rotating three-phase motor involves generating in synchronism with the rotation of the motor a variable duty cycle pulse-width modulated signal for each of the switching circuit components used to supply current to the motor coils. The generated variable duty cycle pulse-width modulated signals control the switching circuit components to selectively place pairs of motor coils in current conducting states and to develop an associated varying voltage for each of the phases. This varying voltage is monitored to identify the one phase that is at a voltage in between the voltages of the other two phases. Then for the identified one phase, the variable duty cycle pulse-width modulated signal is specially generated so that when the switching circuit components of the other two phases are concurrently switched on, the switching circuit component of the identified one phase is not switched on.

The present application relates to a method, circuit, and motor driving system for adaptively adjusting a PWM duty cycle, comprising: sampling a direct current bus voltage and performing a low-pass filtering; determining whether the direct current bus voltage is under-voltage; if yes, entering an under-voltage protection state; and if not, executing the next step; calculating a new duty cycle and a new amplitude; determining whether the new duty cycle is greater than 100%; if yes, applying a weak magnetic control; and if not, adjusting a duty cycle of PWM signals through the new amplitude. Without altering the core current loop, torque loop, or speed loop of the motor driving system, this application adaptively adjusts the PWM duty cycle based on existing sine wave generators and PWM generators, effectively mitigating the impact of direct current bus voltage fluctuations on motor performance, ensuring straightforward operation, and significantly reducing costs.