Abstract: An arithmetic device and a motor drive device including the arithmetic device capable of performing high accuracy motor current calculation, include a control unit performing an arithmetic processing including: acquire a duty ratio; calculate a waiting time according to the duty ratio and a waiting coefficient; detect a shunt current value at a detection timing after lapse of the waiting time; acquire, as a zero-cross current value, the shunt current value; calculate an average value using the shunt current values; and calculate an effective current value by correcting the average value using a correction coefficient.

Abstract: A digital positioner for a valve includes a valve controller configured to obtain a set point value for a valve travel of a valve, and generate a pulse-width modulated current signal based on the set point value. The digital positioner also includes a current-to-pressure converter configured to receive the pulse-width modulated current signal from the valve controller, convert the pulse-width modulated current signal to a pulse-width modulated pressure signal, and provide the pulse-width modulated pressure signal to a pneumatic actuator in the valve to adjust a position of the valve.

Abstract: An electronically commutated motor driving module for driving a motor includes a voltage detector, an electronically commutated motor driver, a current detector, a voltage converter, and a controller. The voltage detector detects supply voltage to generate a voltage detection signal. The electronically commutated motor driver is supplied by the supply voltage to generate, according to an electronically commutated signal, an operating current for driving the motor. The current detector detects the operating current to generate a current detection signal. The voltage converter converts the supply voltage into an internal voltage. The controller is supplied by the internal voltage and generates the electronically commutated signal according to a plurality of control parameters. When the controller determines that a specific event has happened according to the control parameters, the controller stops generating the electronically commutated signal and then stores the control parameters.

Abstract: A stepper motor driver includes an H-bridge including first and second outputs. The H-bridge includes a low-side transistor coupled between the first output and a ground. A reference current circuit is configured to produce a reference current. The reference current circuit has a reference output. An averager circuit includes an input and output. The input of the averager circuit is coupled to the first output of the H-bridge. A comparator includes first and second comparator inputs. The first input of the comparator is coupled to the output of the average circuit and the second input of the comparator is coupled to the reference output.

Abstract: The first square wave control mode using the square wave pulse pattern is used when the voltage acting on the inverter is equal to or higher than the threshold voltage. On the other hand, when the voltage acting on the inverter is lower than the threshold voltage, a square wave pulse pattern is used when the rotation speed of the motor is equal to or higher than the first predetermined rotation speed that is higher than the first resonance region, and the second square wave control mode using the first switching pattern for suppressing the LC resonance in the first resonance region is used when the rotation speed of the motor is lower than the first predetermined rotation speed.

Abstract: A system and method uses field-oriented control (FOC) of a multi-phase motor to prevent thermal runaway of the thermal battery that powers the motor. An offset is applied to the flux command signal to ensure that the power level drawn from the thermal battery exceeds a minimum power level to avoid thermal runaway. This is done without any additional hardware, hence the reduced cost, inefficiencies and packaging volume of such hardware. In different modes, the offset is applied to prevent thermal runaway regardless of torque production, when the system is in failure and torque production is zero, for variable and intermittent periods when torque production is zero, and during normal operation to augment power drawn to produce torque.

Abstract: A rotating machine drive system includes a power supply, an electric motor, a rotating machine, a belt drive transmission unit, an electrical information detection sensor, and a diagnostic unit. The electrical information detection sensor detects a current or a voltage. The diagnostic unit calculates estimated rotational speed information of the rotating machine based on the current or the voltage, calculates a reference rotational frequency from a rotational speed of the electric motor and a ratio between a diameter of the electric motor side pulley and a diameter of the rotating machine side pulley. The diagnostic unit uses a difference or a ratio between the estimated rotational speed information and the reference rotational frequency to determine whether or not there is the transmission abnormality.

Abstract: A motor control system for a folding partition includes a data storage device and processing circuitry. The data storage device is configured to store a normal threshold profile to serve as a threshold for a measured current supplied to a motor to detect abnormal operation of the motor. The motor is configured to drive motion of the folding partition. The processing circuitry is operably coupled to the data storage device. The processing circuitry is configured to generate an adjusted threshold profile to serve as a threshold for the measured current supplied to the motor while moving the folding partition during a transition from an abnormal operational mode to the normal operational mode. The adjusted threshold profile is used for detecting additional abnormal operation of the motor. The processing circuitry is configured to generate the adjusted threshold profile by adjusting at least a portion of the normal threshold profile.

Abstract: A motor driving apparatus for driving a single-phase motor includes an inverter disposed between a battery and the single-phase motor, the inverter applying a first voltage to the single-phase motor at startup and applying a second voltage to the single-phase motor during a normal operation. A stop time period is present after application of the first voltage, application of the first voltage being stopped during the stop time period, and the inverter applies the second voltage after a lapse of the stop time period.

Abstract: A system and method for reducing power consumption and increasing reliability in a solar tracking system is disclosed. The solar tracker comprises a panel, at least one actuator configured to control the orientation of the panel, and a tracking controller. The tracking controller is configured to determine a minimum operating current for the at least one actuator based on a range of motion of the panel, and energize the at least one actuator based on the minimum operating current. The tracking controller determines the minimum operating current based on the range of motion of the panel, specifically the minimum current need to drive the panel through a measured range of motion equal to or substantial similar to the full mechanical range of motion of the panel. Based on the minimum operating current, solar tracker may generate messages to repair or replace an actuator or gearbox, for example.

Abstract: A kinetic energy recovery system with flywheel includes a cascade flywheel doubly-fed electric machine and an electric motor. The cascade flywheel doubly-fed electric machine has a stator end coil, a rotor end coil and a flywheel. The flywheel can store kinetic energy by increasing speed or releasing kinetic energy by decreasing speed. A control circuit has an inverter, a rectifier and a DC bus connecting the inverter and the rectifier. The inverter supplies alternating current to the rotor end coil. The rectifier has an AC end connected to the stator end coil through an AC bus. The rectifier converts alternating current to direct current, so that the inverter can draw power from the DC bus. The electric motor has a phase coil connected to the AC bus. When the cascade flywheel double-fed electric machine decelerates, the system converts mechanical energy into electrical energy.

Abstract: A method for continuous condition monitoring of an electric motor having a rotor and a stator and at least two motor phases, wherein, a first energy loss is associated with the first motor phase and a second energy loss is associated with the second motor phase. The temperature during operation of the electric motor is determined by firstly carrying out a first temperature calculation in order to estimate a temperature of the first motor phase, the first temperature calculation incorporating an energy loss estimation, and a temperature estimation in which a temperature of the first motor phase depends on the estimated energy loss. A second temperature calculation in order to estimate a temperature of the second motor phase utilizes the first temperature value and an energy loss difference between the first and the second energy loss.

Abstract: A motor protecting circuit is provided. A first terminal of each of high-side transistors is coupled to a power supply voltage. A second terminal of each of low-side transistors is grounded. Second terminals of the high-side transistors are respectively connected to first terminals of the low-side transistors. An overvoltage detector circuit is coupled to the power supply voltage of an output circuit. When the overvoltage detector circuit determines that the power supply voltage of the output circuit is higher than a voltage threshold, the overvoltage detector circuit outputs an overvoltage detected signal to a controller circuit. According to the overvoltage detected signal, the controller circuit controls a driver circuit to turn on at least one of the high-side transistors and at least one of the low-side transistors at the same time.

Abstract: A system is provided with a set of removable battery packs and a set of power tools each including a motor, a controller, and a battery receiving portion. For each power tool, the controller is configured to identify a type of battery pack coupled to the battery receiving portion and limit a maximum amount of electric current drawn from the battery pack by the motor based on the identified type of the battery pack. The greater a ratio of an impedance of the motor to an impedance of the battery pack, the less the controller limits the maximum amount of electric current drawn from the battery pack such that for a given battery pack of the set of removable battery packs, the lower the impedance of the motor, the more current the motor draws from the given battery pack.

Abstract: A motor drive device includes a power conversion circuit that drives an AC motor and a controller that controls the power conversion circuit. The controller includes a command current calculation unit generating a command current according to command torque for the AC motor and a current control unit that performs feedback control for adjusting a current applied to the AC motor to the command current. The controller also includes a control gain setting unit that calculates a control gain used for the feedback control based on the command torque and sets the calculated control gain in the current control unit. The control gain setting unit performs control such that a time from a decrease of an absolute value of the command torque to switching of the control gain is longer than a time from an increase of the absolute value of the command torque to switching of the control gain.

Abstract: A system includes a control board comprising: a microprocessor configured to output a PWM signal; a primary shutoff path circuit, an upper MOSFET shutoff circuit, and a lower MOSFET shutoff circuit, each of the circuits configured to receive the PWM signal; a first buffer provided at an output of the primary shutoff path circuit; a second buffer provided at an output of the upper MOSFET shutoff circuit; a third buffer provided at an output of the lower MOSFET shutoff circuit; a first resistor and a second resistor provided in parallel at the first buffer and configured to provide a first feedback signal; a third resistor and a fourth resistor provided in parallel at the second buffer and configured to provide a second feedback signal; and a fifth resistor and a sixth resistor provided in parallel at the third buffer and configured to provide a third feedback signal.

Abstract: The present invention relates to a method of determining the magnetic flux ? of an electric machine, based on measurements (MES) of currents and voltages in the phases of the electric machine, on a dynamic model (MOD) of the magnetic flux and on an adaptive Kalman filter (KAL).

Abstract: A method for phase-voltage based motor period measurement includes generating a commanded phase voltage and applying the commanded phase voltage to a first phase voltage input of an electric motor, a second phase voltage input of the electric motor, and a third phase voltage input of the electric motor, measuring a first period of a phase voltage associated with the first phase voltage input and the second phase voltage input and comparing the measured first period to a frequency of the commanded phase voltage, and, in response to a determination that the measured first period of the phase voltage associated with the first phase voltage input and the second phase voltage input is outside of a range of the frequency associated with the commanded phase voltage, identifying a fault associated with the first integrated circuit or signal path.

Abstract: A rotary electric machine control device for controlling a rotary electric machine having multiple winding sets includes multiple inverter circuits, multiple power supply relays, and multiple controllers provided for respective systems. Each of the controllers is configured to monitor an abnormality of a subject system and an abnormality of a different system and is configured to turn off a power supply relay in the subject system when an abnormality requiring a power supply stop occurs in the subject system. Each of the controllers is further configured to acquire power supply relay information related to a state of the power supply relay of the different system through a signal line, and is configured to monitor the abnormality of the different system based on the power supply relay information.

Abstract: A magnetically de-coupled, separately controlled, electric machine assembly including a radial and one or more axial electric machines, each with rotors mechanically coupled to and arranged to directly drive a single shaft. Each of the electric machines are independently, but cooperatively, controlled by an inverter unit that includes one or more inverters. The axial and radial electric machines are contained in a single housing.