Abstract: Method for diagnosing a fan, in particular in a cooling circuit of an internal combustion engine, a current driving the fan being ascertained. The fan is triggered by a defined trigger signal, and depending on the ascertained current, a diagnosis of whether the fan is defective is performed.

Abstract: Provided are a current detection apparatus having sensor sections detecting motor currents flowing in the windings for the phases of the winding groups, a control apparatus calculating voltage instructions with respect to each winding group, based on the motor current detected by each sensor section, a voltage application apparatus applying voltage to each winding group, based on the voltage instructions, and a failure detection apparatus detecting whether or not each sensor section has failed. The control apparatus, when the failure detection apparatus has detected failure of some of the sensor sections, in accordance with the detection, calculates a voltage instruction with respect to the winding group corresponding to the failure of the sensor section, based on motor current with respect to another winding group detected by the sensor section that can normally detect current.

Abstract: A motor control system comprises a plurality of control apparatuses and a host control apparatus, wherein each of the control apparatuses include a position control unit controlling position based on a position command and commanded speed from the host control apparatus, a speed control unit controlling speed based on a speed command from the position control unit, a current control unit controlling current based on a current command from the speed control unit, and a current amplifier which amplifies motor driving current based on a voltage command from the current control unit, and wherein the current control unit includes a voltage saturation processing unit which determines whether the voltage command has exceeded supply voltage of the current amplifier, and which outputs the result of the determination, and a voltage saturation notifying unit which notifies the host control apparatus of the result of the determination made by the voltage saturation processing unit.

Abstract: In a driver, a changing module changes a rate of discharging the control terminal of a switch at least between a first value and a second value lower than the first value. A measuring module measures a value of a parameter as a function of a current flowing through the conductive path of the switch during a drive signal being in an on state. A control module controls the changing module, as a function of the value of the parameter, to select the first value or the second value as the rate of discharging the control terminal of the switch upon the drive signal directing a change from the on state of the switch to an off state thereof. The control module discharges the control terminal of the switch using the selected value as the rate of discharging the control terminal of the switch.

Abstract: In a rotating electric machine control device, a voltage command value calculation section calculates a voltage command value based on a current command value and a motor current. An inverter power estimation section estimates an inverter power based on the motor current. A power supply current estimation section estimates a power supply current based on the inverter power and a power supply voltage. A limit gain determination section determines a limit gain based on the power supply current and a target power supply current. A limited voltage command value calculation section calculates a limited voltage command value based on the voltage command value and the limit gain. A current limitation section is capable of limiting the power supply current by outputting a command value corresponding to the limited voltage command value to an inverter portion.

Abstract: In a driver, a charging module stores negative charge on the gate of a switching element via a normal electrical path to charge the switching element upon a drive signal representing change of an on state to an off state. This shifts the on state of the switching element to the off state. An adjusting module changes a value of a parameter correlating with a charging rate of the switching element through the normal electrical path as a function of an input signal to the driver. The input signal represents a current flowing through the conductive path, a voltage across both ends of the conductive path, or a voltage at the gate. A disabling module disables the adjusting module from changing the value of the parameter if the drive signal represents the on state of the switching element.

Abstract: According to one embodiment, a controller of a motor includes a driving signal output module, a position detector, a determiner, and an over current detector. The driving signal output module is configured to generate a driving signal for generating a driving current of a motor, a duty ratio of the driving signal being depending on an over current detection signal. The position detector is configured to generate a position detection signal for determining an operating status of the motor by comparing an induction voltage generated by a rotation of a rotor of the motor by the driving current with a predetermined reference voltage. The determiner is configured to determine whether the motor is in a starting state where a rotating frequency of the rotor is smaller than a predetermined value or in a steady state where the rotating frequency of the rotor is equal to or higher than the predetermined value based on the position detection signal.

Abstract: A circuit for controlling a load current through a coil is connected to an output port of a transistor H-bridge that includes two low side transistors and two high side transistors. A current sense circuit is coupled to the H-bridge and configured to provide a representation of the load current provided by the output port. A current regulator is configured to generate a modulated signal dependent on the representation of the load current and a current set-point. The modulated signal has a duty-cycle. A gate control logic drives the individual transistors of the H-bridge on and off in accordance with the modulated signal. A direction signal provides the load current to the coil. The direction signal determines the direction of the load current. An over current detection circuit is coupled to each individual transistor and is configured to signal an over-current by providing an active over-current failure signal when a transistor current through the respective transistor exceeds a respective maximum value.

Abstract: A vehicle includes a polyphase, permanent magnet synchronous electric machine, DC and AC buses, a battery module, a traction power inverter module (TPIM), and a controller. The controller, which is in communication with the TPIM, executes a method to detect a fault condition, fixes the pulse width modulation (PWM) duty cycles of all phases of the electric machine to 50% such that all phases switch simultaneously, and applies a polyphase OPEN state to the AC bus in response to the detected fault condition. The controller then transitions to a polyphase SHORT state by automatically inserting an adjustable deadtime at each PWM switching transition of the TPIM over a calculated ramp duration, thereby transitioning from an initial deadtime to a minimum deadtime over the calculated ramp duration. The transition reduces peak overshoot of the negative d-axis current of the machine during the fault condition.

Abstract: A boost control section for controlling a converter includes a PI control section and a resonance suppression section. The PI control section calculates a basic command value based on a deviation between a drive voltage generated by the converter and a target voltage to equalize the drive voltage and the target voltage. The resonance suppression section calculates, based on the state of variation of the drive voltage, a correction value for correcting the basic command value to suppress the variation. The basic command value is corrected by adding the correction value. First and second drive pulses corresponding to the corrected command value are outputted to the converter.

Abstract: A power tool that includes a motor configured to drive a working element, a power supply that is coupled to the motor to provide power to the motor, a shunt circuit that is coupled to the power supply and the motor, and a controller. The shunt circuit includes a shunt switch and a shunt element and is configured to hold a voltage of the power supply below a high voltage threshold. The shunt switch is switchable between a conducting state, in which the shunt switch conducts current through the shunt element, and a non-conducting state, in which the shunt switch does not conduct current through the shunt element. The controller is coupled to the motor, the power supply, and the shunt circuit and is configured to determine the voltage of the power supply, and control the shunt switch based on the voltage from the power supply.

Abstract: An AC motor drive control device including: an inverter, having a plurality of switching elements subjected to on-off control, for converting a DC voltage to an AC voltage with a desired frequency to drive an AC motor; a motor opening contactor connected between the inverter and the AC motor; a switching operation beforehand detection unit for detecting a switching operation of the motor opening contactor prior to the contact or detach of main contacts and outputting a switching operation beforehand detection signal; and a control unit having an inverter control unit for performing the on-off control for the plurality of switching elements and switching control for the motor opening contactor, and controlling the inverter based on the switching operation beforehand detection signal.

Abstract: A motor drive control device is provided in which if any abnormality occurs in a drive control circuit, drive command signals the drive control circuit generates are interrupted at once, so that an AC motor can be stopped in safety. A monitor control circuit and drive command signal interruption circuit are provided to the drive control circuit that takes variable-speed control of the AC motor supplied with power from a DC drive power source via a semiconductor bridge circuit. If any abnormality occurs in the drive control circuit, the drive command signals the drive control circuit generates are interrupted at once. When starting operation, the drive control circuit and monitor control circuit cooperate with each other to conduct preliminary check as to whether or not the drive command signal interruption circuit operates normally, base on a predetermined time schedule, and stop the AC motor without fail if any abnormality occurs during operation.

Abstract: The disclosed device comprises a duty calculator for calculating a duty command value (Dty), a duty limiter for limiting the duty command value (Dty) to a value according to a limit value (L), a current flow monitor for determining that there is an overcurrent if a current value (Idet) flowing through a winding exceeds a predetermined threshold value (Ithr), and a limit value generator for generating the limit value (L). The limit value generator updates the limit value (L) at predetermined time intervals and for a value corresponding to a difference between the threshold value (Ithr) and the current value (Idet) at a time in order to decrease the current value (Idet) during a period in which the overcurrent is determined.

Abstract: A first inverter and a second inverter supply two coil sets forming a three-phase motor with AC voltages, which are the same in amplitude but shifted by 30° in phase. Current detectors detect phase currents supplied from the inverters to the coil sets. Temperature estimation sections estimate temperatures of the inverters or the coil sets based on an integration value of the phase current detection values. A current command value limitation section limits upper limits of current command values of both coil sets based on the estimated temperatures Tm1 and Tm2. Thus, the inverters and the coils sets are protected from overheating without increasing torque ripple.

Abstract: An apparatus and method for protecting a power system comprising a generator providing power to an alternating current bus, a power converter for converting alternating current power on the alternating current bus to direct current power on a direct current bus, and a direct current load powered by the direct current power on the direct current bus. An undesired condition is identified at the input to the power converter from the alternating current bus. The undesired condition is caused by at least one of the power converter, the direct current bus, or the load. The power converter is disconnected from the alternating current bus in response to identifying the undesired condition for at least a time delay. The time delay is selected such that the power converter is disconnected from the alternating current bus before the alternating current bus is disconnected from the generator due to the undesired condition.

Abstract: A power supply circuit can be used to provide an alternating-current supply voltage to an electric motor. The power supply circuit is supplied by line power. The power supply circuit includes a inverter including at least one pair of transistor for generating a corresponding phase of the plurality of power supply phases. The inverter includes a transistor control circuit for switching the low-side transistor to its conducting state and the high-side transistor to its non-conducting state in case an excess voltage is detected at the input of the inverter.

Abstract: A switch arrangement for an electric motor or generator having a plurality of coil windings that during operation of the electric motor or generator are electrically coupled to form a star point connection and that are arranged to have different voltage phases applied across the respective coil windings, the switch arrangement comprising a rectifier arranged to be coupled to the respective plurality of coil windings, wherein the rectifier is arranged to rectify an alternating current flowing in the respective coil windings and provide the rectified AC current to a DC output; and a switch coupled across the rectifier DC output, wherein the switch is operable to electrically isolate the plurality of coil windings.

Abstract: There is provided a motor driving apparatus in which a current is detected from a connection point between a PMOS transistor and an NMOS transistor of a motor driving circuit, thus reducing a voltage headroom loss due to a shunt resistor. The motor driving apparatus including: a driving unit including a first transistor unit and a second transistor unit connected in parallel between a driving power source terminal and a ground; and a motor driven according to switching of the first and second transistor units; and a detection unit detecting a current from a connection point between a PMOS transistor and an NMOS transistor of at least one of the first and second transistor units.

Abstract: There are provided a motor driving control apparatus and method and a motor using the same, the motor driving control apparatus including: a driving signal generating unit generating a driving control signal controlling a driving of a motor apparatus, a back-electromotive force detecting unit detecting back-electromotive force generated in the motor apparatus, and a controlling unit estimating a driving current of the motor apparatus using the back-electromotive force and adjusting a duty ratio of the driving control signal when the estimated driving current is an overcurrent.

Abstract: A unit for recording operating information of an electronically commutated motor (ECM) is described. The unit includes a system controller communicatively coupled to an ECM. The system controller includes a processing device configured to control the unit. The unit also includes a memory device communicatively coupled to the system controller. The memory device is configured to receive and store ECM operating information provided by the processing device.

Abstract: Provided is an apparatus for operating interior permanent magnet synchronous motor by receiving a first current command of a flux weakening control region I in a system including a detector measuring a position and a speed of a rotor of an IPMSM, the apparatus including a feedback unit transmitting over-modulated voltage information to a correction unit, the correction unit using the rotor speed and the over-modulated voltage information to correct the first current command to a second current command of a flux weakening control region II, a control unit controlling the second current command to output a voltage, a first limit unit limiting an output of the control unit to a maximum voltage synthesizable by an inverter unit, and the inverter unit applying a 3-phase voltage command for following a command torque to the IPMSM using an output of a voltage limit unit.

Abstract: In relation to a multilevel inverter of three levels or more, a decrease in safety due to breakdown is suppressed while avoiding destruction of switching elements. An inverter includes switching elements connected in series between a positive terminal and a negative terminal, reverse blocking switching elements connected one each between connection points of pairs of the switching elements and an intermediate terminal, alternating current output terminals, a control unit that generates control signals for switching between a turning on and turning off of the plurality of switching elements, a control signal interrupt circuit that, on an interrupt signal interrupting the output voltage of the alternating current output terminals being input, interrupts each of the control signals to the first switching elements and second switching elements, regardless of the state of the control signals, and a monitoring unit that diagnoses a breakdown of the control signal interrupt circuit.

Abstract: Apparatus and associated systems and methods may relate to a process for supplying unidirectional current to a load, controlling a reverse electromotive force (REMF), capturing inductive energy from the load, and supplying the captured inductive energy to the load. In an illustrative example, an operating cycle may include a sequence of operations. First, inductive energy captured from the load on a previous cycle may be supplied to the load. Second, energy may be supplied to the load from an external power source. Third, a REMF voltage may be substantially controlled upon disconnecting the power source from the load. Fourth, the load current may be brought to zero by capturing the inductive energy for use on a subsequent cycle. In some embodiments, a single power stage may supply a DC inductive load, or a pair of power stages may be operated to supply bidirectional current to an AC load.

Abstract: A vehicle converts DC power from a power storage device into AC power by an inverter to run by driving a three-phase motor generator. A switching unit is provided at a path electrically connecting the motor generator and the inverter. The switching unit includes a relay corresponding to each phase. Each relay is configured to connect a coil of a corresponding phase in the motor generator to a corresponding driving arm in the inverter, or to a connection node of capacitors connected in series between direct current side terminals of the inverter. When short-circuit failure is detected at a switching element of any one of the phases in the inverter, an ECU switches the relay of the corresponding phase in the switching unit to the side of the connection node.

Abstract: An electric chain saw has an electric drive motor defining a motor-specific characteristic line of the drawn-in current as a function of the rotational speed of the motor. A control unit controls the current flowing through the drive motor below an engaging rotational speed to values below the motor-specific characteristic line. In order to generate an operating point the operator can feel in a working region in a predetermined rotational speed band, a control characteristic line of the electric input power of the electric drive motor as a function of the rotational speed is provided above the engaging rotational speed. The control characteristic line is adapted to reduce the electric input power within the rotational speed band to an approximately even mean power so as to cause the torque of the drive motor to increase within the rotational speed band with falling rotational speed.

Abstract: The invention relates to a blade pitch controlling drive for a wind turbine, comprising an electrical converter, an electric motor that is electrically coupled to the converter, a monitoring unit operable to monitor an electric output current supplied by the converter to the electric motor and determine a state of the load on the converter as a function of the electrical output current, a current limiting unit operable to reduce a maximum possible output current to a nominal current when the state of the load is an overload state when the nominal current when in a non-overload state, and a peak current control unit that can be activated. When activated, the peak current may be provided as the maximum possible output current, regardless of the load state of the inverter at the time of the activation.

Abstract: An installation for an electric motor includes an electrical energy source with elements of different technologies and an inverter for controlling an AC electric motor. The inverter includes an AC current generator for delivering current to a terminal strip to be connected to phases of the electric motor, a supply line, current sensors on certain phases supplying the electric motor, a current sensor on the supply line, an input for receiving information that includes a limit current of the source and a requested-torque setpoint, and a controller for controlling phase currents of the electric motor as a function of the setpoint while maintaining a current of the supply line at an acceptable value as a function of the limit current of the source. The installation makes it possible to impose a maximum current on the current generator without risk of impairing the current generator.

Abstract: A control device for a three-phase AC motor includes: an inverter having switching elements; current sensors for sensing a current in the motor; and a control means having a feedback control operation part for operating a voltage command of each phase and switching the switching elements based on the voltage command. When a positive and negative offset abnormality occurs, the control means executes a positive and negative offset abnormality detection process that the control means compares a value, which is obtained by integrating a variation in a voltage command of each phase over a predetermined detection interval, with a predetermined abnormality threshold value, the voltage command being outputted by the feedback control operation part with respect to a variation in the current caused by the positive and negative offset abnormality.

Abstract: A control device for a three-phase alternate current motor includes: an inverter for driving the motor; current sensors for sensing current in the motor; and a control means having a feedback control operation part for operating a voltage command of each phase and switching the inverter based on the voltage command. When an absolute value of a sum of the current sensed values of three phases is larger than a threshold, the control means: executes a provisional current sensor system abnormality determination; generates a variation visualizing state, in which a response of a feedback control with respect to a variation in the current sensed value caused by the abnormality is delayed or stopped; and performs a phase identification processing for identifying the current sensor on a phase, in which an absolute value of a current deviation is larger than a threshold.

Abstract: A control device for a three-phase alternate current motor includes: a control phase current acquisition means; a monitor phase current acquisition means; a rotation angle acquisition means; a two-phase control current value calculation means; a one-phase current estimated value estimation means; a voltage command value calculation means; an other phase current estimation means for calculating a monitor or a control phase current estimated value; an abnormality detection means for detecting an abnormality in a monitor phase or a control phase current sensor; a number-of-revolutions calculation means for the motor; a number-of-revolutions determination means for determining whether the number of revolutions is not larger than a predetermined determination value; and a switching means between a two-phase control mode when the number of revolutions is not larger than the determination value and a one-phase control mode when the number of revolutions is larger than the determination value.

Abstract: When an earth faulting has occurred in a driving device for driving motor, an electric potential of a vehicle earth is changed. Therefore, in a DC/DC converter, a high-voltage noise intrudes a high-voltage detector through a connection node of a Y capacitor constituted by a pair of capacitors. When the earth faulting of the driving device has occurred, the control device lowers the direct-current side voltage of the inverter in the high-voltage system to reduce the quantity of the high-voltage noise intruding the high-voltage detector.

Abstract: Relays are inserted and connected between a battery and a boosting converter, and other relays are inserted and connected between another battery and another boosting converter. A controller outputs control signals that control opening/closing of the relays. When short-circuit of a switching element occurs in the boosting converters, the controller controls turning-off of the relays such that at least one of order and timing of turning off the relays is changed depending on which of the switching elements is short-circuited.

Abstract: A vehicle includes a polyphase, permanent magnet synchronous electric machine, DC and AC buses, a battery module, a traction power inverter module (TPIM), and a controller. The controller, which is in communication with the TPIM, executes a method to detect a fault condition, fixes the pulse width modulation (PWM) duty cycles of all phases of the electric machine to 50% such that all phases switch simultaneously, and applies a polyphase OPEN state to the AC bus in response to the detected fault condition. The controller then transitions to a polyphase SHORT state by automatically inserting an adjustable deadtime at each PWM switching transition of the TPIM over a calculated ramp duration, thereby transitioning from an initial deadtime to a minimum deadtime over the calculated ramp duration. The transition reduces peak overshoot of the negative d-axis current of the machine during the fault condition.

Abstract: A motor drive device includes a converter which mutually converts power between AC power and DC power, an inverter which converts the DC power into AC power for driving a motor to output to a motor side, and converts regenerated AC power from the motor side into DC power to output to the DC side, a DC link unit which connects a DC side of the converter and a DC side of the inverter, a voltage detecting unit which detects a DC voltage value, an alarm level setting unit which sets an alarm level of the DC voltage value, an alarm determining unit which determines whether or not the DC voltage value exceeds the alarm level, and an alarm reporting unit which instructs the inverter to stop conversion operation when it is determined that the voltage value exceeds the alarm level.

Abstract: A maximum current value determination unit determines the maximum current value of a permanent magnet synchronous motor in order to prevent irreversible demagnetization of a permanent magnet of the permanent magnet synchronous motor that may occur by transient current occurring at the time of short-circuiting of three phases, based on one of a set of irreversible demagnetization causing current value corresponding to permanent magnet temperature and the transient current occurring at the time of the short-circuiting of three phases, and a set of irreversible demagnetization causing magnetic field intensity corresponding to the permanent magnet temperature and demagnetization field intensity of the permanent magnet of the permanent magnet synchronous motor occurring at the time of the short-circuiting of three phases. A current control unit controls the current of the permanent magnet synchronous motor so that the current value of the permanent magnet synchronous motor is less than the maximum current value.

Abstract: An electric power steering device includes: an electric power source for supplying first current; a controller for setting a current instruction value; multiple electric power converters for converting the first current to second current corresponding to the current instruction value; multiple pairs of windings for generating a driving force of a motor; and a failure detection element for detecting failure of the electric power converters and the windings. The controller reduces the current instruction value to be equal to or smaller than a predetermined instruction value of a normal operation when the failure detection element detects the failure. The controller controls the electric power converter in a normal state to supply the second current to a corresponding winding.

Abstract: A motor drive apparatus has a plurality of motor drive parts and a control unit. The control unit performs first and second failure detection processing for the motor drive parts before starting to drive the motor. If the first motor drive part is determined to have failure by the first failure detection processing, a first power supply relay for the first motor drive part is turned off and the second failure detection processing for the first motor drive part is inhibited. If the second motor drive part is determined to have no failure by the first failure detection processing and then by the second failure detection processing, the motor is started to operate.

Abstract: A motor driving apparatus capable of detecting during operation a ground fault and a phase-to-phase short circuit by distinguishing one from the other is provided while minimizing an increase in cost. The sum of three-phase AC currents supplied from a three-phase AC power supply to an AC/DC converter is detected by a current sensor. When overcurrent is detected by an overcurrent detector, if the sum of the currents detected by the current sensor is zero, it is determined that the fault is a phase-to-phase short circuit, but if the sum is not zero, it is determined that the fault is a ground fault.

Abstract: In a driver, a clamping module executes a clamping task that clamps an on-off control terminal voltage to be equal to or lower than a clamp voltage for a predetermined time during charging of the on-off control terminal of the switching element. The clamp voltage is lower than an upper limit of the voltage at the on-off control terminal of the switching element. A measuring module measures a parameter value correlated with a sense current correlated with a current flowing between input and output terminals of the switching element. A limiting module discharges the on-off control terminal to limit flow of the current between the input and output terminals if the value of the parameter exceeds a threshold. A setting module variably sets a length of the predetermined time as a function of the parameter value during charging of the switching element's on-off control terminal.

Abstract: A semiconductor device that controls a motor driving device. The semiconductor device includes: a position detection section that detects changes in a turning position of a rotor provided at a motor and outputs detection signals corresponding to the changing turning position; a first switching section that, in accordance with the detection signals, outputs ground switching signals, which switch which end portion of a coil is connected to a ground side, to a first switching circuit; and a second switching section that, in accordance with the detection signals, outputs connection switching signals, which switch which end portion of the coil is connected to a driving power supply side, to a third switching circuit that controls the switching of connections between the end portions of the coil and the driving power supply side by a second switching circuit.

Abstract: An inverter circuit is provided for a plurality of coils and includes switching elements forming switching element pairs in correspondence to each phase of the coils. Current detection sensors detect currents flowing low-side FETs, respectively. A control circuit has a failure detection section, which detects arm short-circuit failure of the element pairs based on current values detected by the current detection sensors at timing when one or the other of all the low-side FETs and all the high-side FETs are turned on and turned off, respectively.

Abstract: An inverter includes a voltage command generator generating a voltage command value according to an externally specified voltage value, a PWM signal generator generating a PWM signal according to the voltage command value and frequency command value, and a switching unit generating a three-phase AC power according to the PWM signal. The voltage command generator decreases the voltage command value if the output current increases, to prevent the rotation speed of a prime move from suddenly changing. If the output current exceeds a preset upper current threshold, the voltage command value is clamped at a preset minimum output voltage, thereby securing the minimum output voltage for an increase in the output current.

Abstract: An electric power steering control device includes: a vibration extracting filter for performing filter processing on a rotation speed of a motor to reduce a gain on a low frequency side so as to output a vibration-component signal; a current variable gain map for detecting a current flowing through the motor as a first state quantity so as to calculate a current variable gain based on the current; a rotation-speed variable gain map for detecting the rotation speed of the motor as a second state quantity so as to calculate a rotation-speed variable gain based on the rotation speed; a correction mechanism calculating a vibration suppression current; and current controller calculating a target current so as to control the current flowing through the motor.

Abstract: A motor drive system control apparatus includes: a direct current power supply; a three-phase alternating current motor; a first power converter including switching circuits corresponding to each of three phases of the three-phase alternating current motor and a smoothing condenser disposed electrically in parallel with the switching circuits; an estimating device for estimating peak generation timing in which a peak is generated in an inter-terminal voltage VH of the smoothing condenser on the basis of at least one of an operating condition of the three-phase alternating current motor; a switching condition of the switching circuits corresponding to each of the three phases; and a controlling device for controlling a drive condition of the first power converter so the inter-terminal voltage VH (or a VH peak) in the peak generation timing decreases, for a predetermined period from start timing set in a time domain before the estimated peak generation timing.

Abstract: An electric vehicle includes an inverter unit and an ECU. The inverter unit or the ECU includes a magnetic force estimator that estimates a magnetic force of a permanent magnet structure associated with a motor rotor of a motor unit. The inverter unit or the ECU may also include a determiner for the estimated magnetic force and an abnormalities-responsive motor drive limiter. The estimator is configured to estimate, according to a predefined rule, the magnetic force, based on at least two detection signals selected from a group consisting of a detection signal indicating a rotational frequency of the motor unit, a detection signal indicating a motor voltage of the motor unit and a detection signal indicating a motor current of the motor unit.

Abstract: Embodiments of the invention provide a method of operating a safety vacuum release system (SVRS) with a controller for a pump including a motor. The method can include measuring an actual power consumption of the motor necessary to pump water and overcome losses. The method can include triggering the SVRS when a dynamic suction blockage is identified in order to shut down the pump substantially immediately. The SVRS can also be triggered when a dead head condition is identified based on the actual power consumption.

Abstract: A control device for an AC rotating machine having a current limiting function of protecting the AC rotating machine and a driving unit such as an inverter from over-current, in which the control device has the reliable current limiting function in driving the AC rotating machine with known or unknown electrical constant. In the control device, a frequency correction value arithmetic unit has an amplification gain computing element for computing an amplification gain based on an electrical constant of the AC rotating machine and an amplifier for computing a frequency correction arithmetic value based on the amplification gain computed by the amplification gain computing element and the current of the AC rotating machine, in which the frequency correction arithmetic value is outputted as a frequency correction value in a predetermined running state of the AC rotating machine.

Abstract: A steering control apparatus includes a direct current power source, a three-phase alternating current motor, and a motor driving circuit. An emergency switching element is provided on at least two phases of a three-phase power supply line connected to the three-phase alternating current motor within the motor driving circuit, and the emergency switching element is turned off when an abnormality occurs such that the motor driving circuit is disconnected from the three-phase alternating current motor. The emergency switching element is a MOSFET, and the MOSFETs are provided in pairs in each of the two phases of the three-phase power supply line. Further, parasitic diodes of the pairs of MOSFETs are disposed in opposite orientations to each other.

Abstract: An object is to provide a driving controller for an AC motor that can prevent generation of an excessive voltage between lines of a motor and between contacts of a motor cut-off contactor and a continuous arc between contacts of the motor cut-off contactor, regardless of the type of a fault occurred, even when a phase in which a current zero point is not generated and a phase in which a current zero point is generated coexist in a fault current that flows between an inverter and the motor. A control unit is configured to open a motor cut-off contactor not at a time when a state of a detected current is determined to be abnormal but at a time when the state of the current is determined to be normal, even when a basic contactor-close command MKC0 becomes off (L level).