A novel motor controller controls a stepping motor and includes a command value calculator to calculate and output a speed command value and an angle command value based on a reference clock. A control method selector is included to select one of the open-loop control and the closed-loop control in accordance with the speed command value. A command value output unit is included to output a first target value as the first current command value when the open-loop control is selected and outputs a second target value as the second current command value when the closed-loop control is selected. The motor controller controls the stepping motor based on the first target value when the open-loop control is selected and the second target value when the closed-loop control is selected.

A control circuit includes a storage unit, a generation unit, an update unit, and a rotation control unit. The storage unit stores a predetermined number of register values to designate a step frequency of a stepper motor. The generation unit generates a micro step clock signal every time a period corresponding to each of the predetermined number of register values stored in the storage unit elapses. The update unit updates the predetermined number of register values stored in the storage unit every time the generation unit generates the predetermined number of micro step clock signals. The rotation control unit supplies a phase current based on the micro step clock signal generated by the generation unit to the stepper motor to rotate a rotor of the stepper motor by a micro step angle found by equally dividing a step angle of the stepper motor into the predetermined number.

A control circuit includes a storage unit, a generation unit, an update unit, and a rotation control unit. The storage unit stores a predetermined number of register values to designate a step frequency of a stepper motor. The generation unit generates a micro step clock signal every time a period corresponding to each of the predetermined number of register values stored in the storage unit elapses. The update unit updates the predetermined number of register values stored in the storage unit every time the generation unit generates the predetermined number of micro step clock signals. The rotation control unit supplies a phase current based on the micro step clock signal generated by the generation unit to the stepper motor to rotate a rotor of the stepper motor by a micro step angle found by equally dividing a step angle of the stepper motor into the predetermined number.

The disclosure relates to an autonomous apparatus, moving and performing preset work in a defined working area, the autonomous apparatus including an energy module supplying energy to the autonomous apparatus, a motor, a sensor circuit, and a control circuit, the motor obtaining the energy from the energy module, to drive the autonomous apparatus to move and/or work in the working area, the sensor circuit detecting working parameters and environmental parameters of the autonomous apparatus, and transmitting detection results to the control circuit, the control circuit controlling the operation of the motor according to a signal transmitted by the sensor circuit, where the motor is a sensorless brushless motor, and before the motor rotates, the control circuit measures a resistance value of the motor, and estimates, one the basis of the resistance value of the motor, a rotor position of the motor, so as to control the operation of the motor.

A motor control device according to an embodiment comprises a first signal generator, a second signal generator, a main controller, and a driver. The first signal generator is configured to generate, based on a clock signal indicating a stepping drive cycle of a motor, a first control signal. The second signal generator is configured to generate, based on a command phase indicating a target phase of a rotor of the motor, a second control signal. The main controller is configured to control the first signal generator and the second signal generator to output at least one of the first control signal and the second control signal. The driver is configured to drive the motor based on at least one of the first control signal and the second control signal.

Provided are a method and system for controlling an electric motor, and a controller. The method comprises: controlling an electric motor to operate in an open-loop manner; determining whether a rotational speed of the electric motor reaches a preset rotational speed; if so, determining whether the absolute value of an angle difference between an open-loop angle and a calculated position angle of the electric motor is greater than a preset angle; and if the absolute value of the angle difference is less than or equal to the preset angle, controlling the electric motor to operate in a closed-loop manner so as to avoid the situation where the electric motor cannot operate stably due to problems such as electric motor speed vibration caused by too large an angle difference between the open-loop angle and the position angle.

Provided are a method and system for controlling an electric motor, and a controller. The method comprises: controlling an electric motor to operate in an open-loop manner; determining whether a rotational speed of the electric motor reaches a preset rotational speed; if so, determining whether the absolute value of an angle difference between an open-loop angle and a calculated position angle of the electric motor is greater than a preset angle; and if the absolute value of the angle difference is less than or equal to the preset angle, controlling the electric motor to operate in a closed-loop manner so as to avoid the situation where the electric motor cannot operate stably due to problems such as electric motor speed vibration caused by too large an angle difference between the open-loop angle and the position angle.

A stepping motor control device is provided, which controls a stepping motor including a rotor position detector by micro-step driving. The control device has a plurality of operation modes including an adjustment mode and a use mode. In the adjustment mode, the control device generates control data for a closed loop control for controlling the winding current of the stepping motor based on the detection value of the rotor position detector, and performs a stepping motor acceleration operation and a stepping motor deceleration operation according to the control data. In the use mode, the control device performs the stepping motor acceleration operation and the stepping motor deceleration operation so that a winding current observed in the adjustment mode is reproduced by an open loop control for controlling the winding current of the stepping motor based on the control data generated in the adjustment mode.

A stepping motor control device is provided, which controls a stepping motor including a rotor position detector by micro-step driving. The control device has a plurality of operation modes including an adjustment mode and a use mode. In the adjustment mode, the control device generates control data for a closed loop control for controlling the winding current of the stepping motor based on the detection value of the rotor position detector, and performs a stepping motor acceleration operation and a stepping motor deceleration operation according to the control data. In the use mode, the control device performs the stepping motor acceleration operation and the stepping motor deceleration operation so that a winding current observed in the adjustment mode is reproduced by an open loop control for controlling the winding current of the stepping motor based on the control data generated in the adjustment mode.

An air manifold system for supplying an agricultural product to a plurality of metering devices comprises a product hopper having a product flow cavity, the product cavity separated from a first plenum by an air agitator sandwiched between the first plenum and the product flow cavity. The hopper comprises a plurality of nozzles extending through a wall of the hopper. A venturi assembly is in fluid communication with at least one nozzle. A first forced air stream flows through the first plenum and the air agitator into the product flow cavity to agitate and entrain agricultural product in the first air stream, and the first air stream carries the entrained agricultural product into the nozzles. A second forced air stream flows through the venturi assembly to accelerate the first air stream and the entrained product towards and through the supply hoses connected to the nozzles.