A method for controlling switched reluctance machine (SRM) utilizing a SRM control system. The method allows for adaptive pulse positioning over a wide range of speeds and loads. An initial rotor position is provided for the SRM utilizing an initialization mechanism. A pinned point on a phase current waveform is defined during an initial current rise phase of the current waveform. A slope of the current rise is determined as the current waveform reaches the pinned point. The slope is then fed to the commutation module of the SRM control system. An error signal from calculated inductance or current slope is used as an input to a control loop in the SRM control system. The time determining module determines an optimum time signal to fire a next pulse. The optimum time signal is fed to the SRM for turning the plurality of SRM switches to on and off states.

Monitoring conditions of an electric motor using stator current and voltage signals from power supplied to the motor is disclosed herein. The stator voltage and current signals may be used to calculate instantaneous power values which may be used to calculate slip. The slip may be used to monitor for a locked rotor condition during startup of the motor. The slip value may be used to provide thermal protection to the electric motor.

System, apparatus, and methods for controlling a motor by using servo-to-edge direction feedback are disclosed. An exemplary apparatus comprises: a fiber optic rotary junction (FORJ) having a rotatable portion; a motor to rotate the rotatable portion; a connector to connect the rotatable portion to a rotatable fiber of an imaging probe; a sensor positioned in close proximity to a target and configured to output a signal indicative of which one of at least two distinguishable regions of the target is proximal to the sensor; and a controller configured to control the rotational direction of the motor based on the sensor signal. In one embodiment, the motor is a servo-motor, and the rotation of the motor and/or rotatable portion is controlled by a servo-loop to change the rotation direction of the motor back-and-forth around a predetermined rotational position without the use of an encoder.

A power tool is provided including a brushless motor having a stator defining a plurality of phases and a rotor. A power unit is provided including power switches operable to deliver power to the motor. A primary controller is interfaced with the power unit to output drive signals to drive the phases of the motor over a series of sectors of the rotor rotation. The primary controller measures a back-electromotive force voltage of the motor and transitions motor commutation from the present sector to the next sector based in relation to the back-EMF voltage. A second controller is provided to receive at least one of the drive signals, calculate a speed and/or direction of rotation of the motor from the drive signals, and take corrective action to cut off supply of power to the motor if it detects an overspeed condition or incorrect direction of rotation.

A power tool is provided including a brushless motor having a stator defining a plurality of phases, a rotor rotatable relative to the stator, and power terminals electrically connected to the phases of the motor. A power unit is provided including power switches. A control unit is interfaced with the power unit to output a drive signal to one or more of the motor switches to drive the phases of the motor over a series of sectors of the rotor rotation. The control unit is configured detect incorrect rotation of the rotor by applying a first series of voltage pulses to a present sector and a second series of voltage pulses to a previous sector, measuring motor currents associated with the first and second series of voltage pulses, and comparing corresponding motor current measurements to detect a transition from the present sector to the previous sector.

A power tool is provided including a brushless motor having a stator defining a plurality of phases and a rotor. A power unit is provided including power switches and a control unit outputs a drive signal to the motor switches to drive the phases of the motor using a trapezoidal control scheme over a series of sectors. The control unit sets a conduction band within which each phase is commutated to a baseline value that is greater than 120 degrees, sets at least one commutation transition point as a function of the set conduction band, and within each sector, monitors an open-phase voltage of the motor to detect a back electromotive force (back-EMF) voltage of the motor and control commutation of at least one phase based on the open-phase voltage of the motor in relation to the at least one commutation transition point.

A device and method for detecting the number of revolutions of a sensorless electric park brake (EPB) motor. The device for detecting the number of revolutions of a sensorless motor includes: an actuator driving motor used to set and release a parking brake of an EPB system; an electronic control module for controlling the motor, a vehicle battery for supplying power to the motor and the electronic control module; and a main processing unit for receiving an output signal of the electronic control module and estimating the number of revolutions of the motor, wherein the electronic control module further includes a ripple measuring unit for receiving an output signal of the motor and measuring a ripple of the motor.

A reagent bottle cleaning device is provided, comprising a base, a cleaning assembly, and a cleaning block. The cleaning assembly comprises a pushing cylinder and a mounting plate. A plurality of mounting grooves are disposed on the mounting plate. Each mounting groove is provided with a cleaning motor. The cleaning motor is provided with a cleaning screw rod. The cleaning block is provided with cleaning grooves corresponding to the cleaning screw rods. Injecting pumps are disposed between the cleaning block and the cleaning assembly. The injecting pumps are connected to the base by lifting cylinders. Full-automatic quick cleaning of reagent bottles can be realized under the effect of a main control chip.

A brake control system includes: a plurality of motors each provided with a brake device and a position detecting section; and a brake control device that controls a plurality of the brake devices using one brake-oriented power source. The position detecting section includes a position detecting circuit section and a communication circuit section. The brake device includes: a current detecting section that detects a brake current flowing through a brake coil of an electromagnetic brake; and an insulating circuit section that electrically insulates the current detecting section and the communication circuit section. The communication circuit section transmits to the brake control device the brake current acquired via the insulating circuit section. The brake control device includes a fault specifying section that specifies the faulty brake device based on a plurality of detection signals detected by a plurality of the current detecting sections.

A control method of a motor rotation speed may include calculating a q-axis potential difference of a synchronous coordinate system for controlling a q-axis current of the synchronous coordinate system based on a target rotation speed of a motor and a measured rotation speed value of the speed sensor, calculating a voltage command of the synchronous coordinate system based on the calculated q-axis potential difference of the synchronous coordinate system, and controlling an inverter connected to the motor according to the calculated voltage command of the synchronous coordinate system.