Abstract: A system and method of determining the temperature of a rotating electromagnetic machine, such as an electric motor or generator. A temperature calibration parameter is calculated based on the temperature of an object situated close to the motor, such as a motor drive connected to the motor, and a first resistance value of the winding. In exemplary embodiments, the motor drive and first resistance value are determined only after the motor has been idle for some predetermined time period. Once the calibration parameter is calculated, the processor uses it along with subsequent resistance measurements to calculate the temperature of the motor.

Abstract: A method of controlling a DC motor is presented. In a determining action, a thermal power dissipation is determined from a motor input and a motor velocity. In another determining action, a motor temperature is determined based on a thermal model using the thermal power dissipation. In an adjusting action, a usage of the motor is adjusted, taking the motor temperature into account.

Abstract: The invention relates to a method for temperature limitation according to the current and/or voltage, for an actuating device (10) associated with an electric motor (M), especially a fan regulator (12) of a motor vehicle, the temperature limitation being carried out according to at least one operating parameter of the motor (M). The invention also relates to a corresponding device (1) and a fan regulator (12).

Abstract: An accurate slip calculation for providing monitoring and protection to an electric motor. The slip calculation is made using a minimum value of stator resistance as the initial stator resistance, where the minimum value of stator resistance is the minimum value of stator resistance calculated during an initiation period of the motor. The initiation period may be a predetermined time period or a predetermined number of cycles during the motor startup. The initiation period may start after a predetermined settling time or after a predetermined condition is met.

Abstract: A heating value calculation part obtains a substantial heating value based on the difference between a heating value and a radiating value attributed to a motor supply current. The radiating value is obtained by a difference between a motor estimation temperature Td and an ambient temperature Tm. The heating value is cumulated in the heating value calculation part and the cumulated value is inputted to a cumulated buffer. A cumulated value TS which is obtained by adding an initial temperature T0 to the cumulated value Td is inputted to a target current value ratio map and a target current value upper limit map. One of the target current values is selected and the selected target current value is inputted to a current feedback control part. The current feedback control part controls a motor output part such that the motor supply current is converged to the target current value.

Abstract: Thermal variable-operation regulator that regulates the operation of an operating device by progressively limiting the operation of the operating device (24) as a limitation temperature (Tset) increases. The limitation temperature (Tset), based on which the operation of the operating device (24) is limited, is set to a smoothed temperature (Ttmp), obtained by performing a predetermined smoothing process on the detected temperature (Tiny), by a limitation temperature setting means when a change amount (AT) of the detected temperature (Tiny) is equal to or less than a predetermined change amount (Tref). However, when the change amount (AT) of the detected temperature (Tiny) is greater than the predetermined change amount (Tref), the limitation temperature (Tset) is set without using the detected temperature (Tiny).

Abstract: An electric power steering device that can estimate an ambient temperature and apply current limiting without using ambient temperature detecting means is provided. The electric power steering device includes a motor that supplements the driver's steering force, a controller that determines and controls the quantity of current passed to the motor, and vehicle speed detecting means. The electric power steering device includes ambient temperature estimating means provided with a vehicle speed signal input from the vehicle speed detecting means and limits the quantity of current passed to the motor according to an output from the ambient temperature estimating means.

Abstract: To provide a motor control apparatus, including a rotational number detecting means for detecting the rotational number of a motor; a current detecting means for detecting a motor current; a voltage detecting means for detecting an impressed voltage to be supplied to a motor; a temperature estimating means for obtaining a motor temperature from the rotational number of a motor, the motor current, and the impressed voltage; and a protection signal generating means for generating an operational signal in order to protect the motor when the obtained motor temperature exceeds a predetermined value.

Abstract: A method and system for estimating a parameter of an electric machine, including a controller and a switching device, the controller responsive to at least one of: a current sensor, and a temperature sensor. Where the controller executes a parameter estimation process, which is responsive to at least one of: a current value and a temperature estimate and the resultant of the parameter estimation process representing an estimated parameter of the electric machine. The parameter estimation includes a method for estimating a temperature of the electric machine comprising: the temperature sensor operatively connected to and transmitting a temperature signal corresponding to a measured temperature to a controller, which executes the temperature estimation process responsive to a temperature signal from the temperature sensor.

Abstract: An electronic apparatus externally detects open protector contacts inside of a compressor. The compressor includes a compressor motor having a run winding and a start winding. The compressor motor also includes internal protector contacts that open the electrical circuit to the “C” terminal in a protection condition. A compressor running indicator circuit is electrically connected between the “S” and the “R” terminals to indicate a compressor running condition. Also, a protection indicator circuit is electrically connected between the “C” and the “S” terminals to indicate a voltage present across the “C” and the “S” terminals. The protection indicator circuit is also coupled to the compressor running indicator circuit such that the protection indicator circuit is disabled when the compressor is running normally and the protection indicator is enabled and indicates when protector contacts open inside of the compressor.

Abstract: A thermal overload protection for an electrical device, particularly an electric motor (M), measures a load current supplied to the electrical device (M), and calculates the thermal load on the electrical device on the basis of the measured load current, and shuts off (S2) a current supply (L1, L2, L3) when the thermal load reaches a given threshold level. The protection comprises a processor system employing X-bit, preferably X=32, fixed-point arithmetic, wherein the thermal load is calculated by a mathematic equation programmed into the microprocessor system structured such that a result or a provisional result never exceeds the X-bit value.

Abstract: A thermal overload protection for an electrical device, particularly an electric motor (M), measures a load current supplied to the electrical device (M), and calculates the thermal load on the electrical device on the basis of the measured load current, and shuts off (S2) a current supply (L1, L2, L3) when the thermal load reaches a given threshold level. The protection comprises a processor system employing X-bit, preferably X=32, fixed-point arithmetic, wherein the thermal load is calculated by a mathematic equation programmed into the microprocessor system structured such that a result or a provisional result never exceeds the X-bit value.

Abstract: A system for automatically cutting off the energy from, and shutting down an electric generator positioned inside an aircraft engine and supplying electrical power to the aircraft. The system comprising an electric generator, a control panel and driving cabin. The generator having a sensor positioned inside the generator sensing the oil pressure and outputting a signal in response to the oil pressure reaching a predetermined level; a generator disconnect solenoid; and an automatic generator connector receiving the output of the sensor, and in response removing the electrical power supplied by the generator to the aircraft and outputting a signal to the generator disconnect solenoid causing the generator to shut down, and also outputting a control signal. A control panel receiving the control signal and in response outputting a driving cabin control signal. A driving cabin control system receiving the driving cabin control signal and activating a warning system in response.

Abstract: An actuator for a clutch or gear mechanism in a motor vehicle comprises an electric motor and an incremental encoder. The encoder comprises a position measurement signal output at which a position measurement signal can be output which has a number of different signal states, each of which is assigned to a relative position between a primary part and a secondary part of the electric motor. For the commutation of the electric motor, the position measurement signal output is connected to a position measurement signal input of a control device for a motor winding of the electric motor. The control device comprises a device for checking the plausibility of the position measurement signal and is designed in such a manner that on the occurrence of an implausible signal state the power supply to the electric motor is disconnected and/or the power of the electric motor is limited.

Abstract: A technique for reducing nuisance tripping is disclosed in which a desired limit temperature is determined for a component of a motor system. The limit is compared to actual temperature signals, or signals indicative of temperature of the component. The component may be the conductor or conductors providing power to the motor. A counter is augmented when the actual temperature exceeds the limit. The limit may be computed, such as based on a heating model. A trip signal is generated only when the actual temperature has exceeded the limit for a predetermined number of periods. The counter may be reset if the actual temperature drops below the desired limit.

Abstract: A motor controller includes: an estimated temperature calculating section that calculates and stores an estimated temperature of a motor, and a control section that can perform a drive control of the motor only when this estimated temperature is not larger than a predetermined value. When the motor is stopped, a second temperature gradient while the temperature of the motor decreases from a stop-time temperature to a predetermined first set temperature is stored in correspondence to the stop-time temperature. The first temperature gradient corresponding to the estimated temperature at a time when the motor is stopped is calculated by using the first temperature gradient storing means, if the estimated temperature stored in the estimated temperature storing means when the motor is stopped is larger than the first set temperature.

Abstract: A specially designed rotation speed controller for fans, in addition to basic components like variable resistor, the controller has also been equipped with special components such as TRIAC, micro limit switch, and glass tube fuse, which allows said controller to precisely control the on/off status and the rotation speed of the fan, and the controller also provides power-off protection against power overload.

Abstract: A thermal overload protection for an electrical device, particularly an electric motor (M), measures a load current supplied to the electrical device (M), and calculates the thermal load on the electrical device on the basis of the measured load current, and shuts off (S2) a current supply (L1, L2, L3) when the thermal load reaches a given threshold level. The protection comprises a processor system employing X-bit, preferably X=32, fixed-point arithmetic, wherein the thermal load is calculated by a mathematic equation programmed into the microprocessor system structured such that a result or a provisional result never exceeds the X-bit value.

Abstract: A permanent magnet (PM) machine has a fault condition mechanism disposed within a back iron of the stator portion, the mechanism operational to automatically reduce fault currents associated with the PM machine during a fault condition. The fault condition mechanism disposed within the stator back iron is reconfigurable to automatically reduce internal heat associated with the PM machine during a fault condition. A method of reconfiguring the PM machine upon detecting a fault condition includes the steps of 1) selecting the reconfigurable fault condition mechanism from a) a plurality of magnetically anisotropic rotatable cylinders, b) a plurality of ferrofluid-filled cavities, and c) a dual-phase material selectively embedded within the stator core; and 2) reconfiguring the fault condition mechanism to automatically reduce fault currents or internal heat associated with the PM machine upon detection of a fault condition.

Abstract: Motor start circuit for an induction motor, particularly a single-phase AC induction motor, with a main winding (4) and an auxiliary winding (5), which are supplied with current, particularly alternating current, via current supply connections (24, 25), and with a start switching device (15) serving the purpose of interrupting the current flow through the auxiliary winding (5) after the start of the motor, the start switching device (15) being connected to a control device (20) via a connector (18), the control device (20) being connected between the current supply connections (24, 25), and with a winding protection switch (28), which is normally closed and which opens on the occurrence of a fault. The invention is characterised in that the control device (20) is connected to the winding protection switch (28) via at least one further connector (22, 17), preferably via at least one further connector (22, 17) and the auxiliary winding (5).

Abstract: Thermal variable-operation regulator that regulates the operation of an operating device by progressively limiting the operation of the operating device (24) as a limitation temperature (Tset) increases. The limitation temperature (Tset), based on which the operation of the operating device (24) is limited, is set to a smoothed temperature (Ttmp), obtained by performing a predetermined smoothing process on the detected temperature (Tiny), by a limitation temperature setting means when a change amount (AT) of the detected temperature (Tiny) is equal to or less than a predetermined change amount (Tref). However, when the change amount (AT) of the detected temperature (Tiny) is greater than the predetermined change amount (Tref), the limitation temperature (Tset) is set without using the detected temperature (Tiny).

Abstract: An apparatus is disclosed that drives an inductive load according to a control signal from an external controller transmits temperature data to it for indicating a condition of the inductive load through a line driver. The external controller regenerates the control signal according to the temperature data. According to the control signal, the apparatus operates a pair of power supply circuits to complementarily supply power to the load. Thermal conditions of the power supply circuits and the line driver are monitored for detecting an overheat condition. The transmission of temperature data to the external controller is enabled as long as no overheat condition is detected in both of the power supply circuits and line driver. If an overheat condition is detected in at least one of the power supply circuits and line driver, heat protection is performed and the overheat condition is communicated to the external controller.

Abstract: Disclosed is an electric motor comprising a temperature monitoring device which is provided with at least two temperature sensors that have different temperature characteristics and are connected to terminal clamps by means of electrical wires, whereby it is possible in an advantageous manner to connect regulating devices having different temperature sensor input characteristics to the electric motor.

Abstract: The invention relates to thermal pre-ignition agents and to their use as thermal fuses, in particular for use in gas generators of motor-vehicle safety systems.

Abstract: A method, apparatus or computer program implements an overload prevention approach involving monitoring a speed of a motor; detecting an overload condition of the motor based on the monitored speed; and controlling an operation of the motor according to the detected overload condition.

Abstract: A controller is operable in one of a plurality of operational modes, which include an estimated temperature computation performing mode for performing computing of an estimated temperature of the motor and an estimated temperature computation non-performing mode for stopping the computing of the estimated temperature of the motor. An operational mode of the controller is changed from the estimated temperature computation performing mode to the estimated temperature computation non-performing mode according to a predetermined condition in a stopped state of the motor.

Abstract: A motor controller is provided with: an estimated temperature calculating means that calculates an estimated temperature of a motor; and a control unit that can perform a driving control of the motor only when the estimated temperature is not larger than a predetermined value. A mode switching means switches the control unit and the estimated temperature calculating means between in a normal operation mode in which they can drive the motor and in a sleep mode in which electric power consumption thereof is smaller than in the normal operation mode in accordance with a predetermined condition while the motor is stationary. An activating means activates the estimated temperature calculating means in the sleep mode for a predetermined active time every time a predetermined sleep time is elapsed.

Abstract: A protection system for an electrical device may include at least one temperature sensitive element located in a region adjacent to a component of the electrical device and configured to provide an output related to an actual temperature in the region. The system may also include a controller configured to determine the actual temperature in the region based on the output of the at least one temperature sensitive element and to determine a predicted temperature of the component based on the actual temperature in the region and on a predetermined heat dissipation characteristic of the electrical device.

Abstract: A motor controller includes: a motor control part for driving and controlling a motor; an estimated temperature computing part for computing an estimated temperature of a winding of the motor; and a motor protecting part for protecting the motor from being burned when the estimated temperature becomes larger than a predetermined temperature. A temperature rise value of the estimated temperature is computed according to operating conditions of the motor at the time of passing electric current through the winding. This temperature rise value is added to an estimated temperature stored in the estimated temperature storing part to update the estimate temperature. To compute the temperature rise value, an optimum temperature rise value is computed by the use of a plurality of temperature-rise value computing expressions.

Abstract: An electric power steering device that can estimate an ambient temperature and apply current limiting without using ambient temperature detecting means is provided. The electric power steering device includes a motor that supplements the driver's steering force, a controller that determines and controls the quantity of current passed to the motor, and vehicle speed detecting means. The electric power steering device includes ambient temperature estimating means provided with a vehicle speed signal input from the vehicle speed detecting means and limits the quantity of current passed to the motor according to an output from the ambient temperature estimating means.

Abstract: The invention relates to a circuit (1) for protecting against overload of an electric motor (2), more particularly an electrically powered air blower for a vehicle, with the purpose of providing sufficient and appropriate protection even when several electric motors are connected in series. Said circuit is provided with at least one switching element (6) for controlling two series connected electric motors (2) independent of revolutions, in which a switch element (14) configured as a make contact element (12) is connected in parallel to the electric motor (2), said switch element causing short circuiting of the corresponding electric motor (2) in case of overheating.

Abstract: The invention relates to a regulating device (1) for a motor, comprising a housing (2) which can be associated with said motor and in which a control unit (5) and an actuator (6) are arranged. Due to heat-related reasons, said device can only be used in an encapsulated manner, for example close to a motor. In order to solve this problem, the actuator (6) comprises an electromagnetic switching element (8a,8b) and the control signal (7) for the same is designed as a timing signal which is measured—taking into consideration at least one heat source inside or optionally outside the housing (2)—in such a way that the operating temperature of the electromagnetic switching element (8a,8b) is below an upper authorised limiting value.

Abstract: An anti-pinch and electric motor protection device includes a positive temperature coefficient circuit protector having a predetermined temperature threshold and is adapted to be in electrical series with a DC circuit to allow current flow in a first direction and in a second opposite direction when the positive temperature coefficient circuit protector is below the threshold and to block current flow in either direction when the positive temperature coefficient circuit protector is above the threshold. A diode electrically in parallel with the positive temperature coefficient circuit protector is adapted to block current flow in one of the directions.

Abstract: The protective relay for an induction motor includes a first program function which establishes a first thermal threshold value for a start condition of the motor, using a start condition thermal model. The thermal condition of the motor is determined by measuring the motor's thermal response to stimulus. A comparator compares the start condition thermal representation with the first thermal threshold value and monitors whether the first thermal threshold value is exceeded by the start condition thermal representation. A second thermal threshold value is established for a run condition of the motor, including a selected time constant which results in the time-current curves of the start and run conditions being substantially continuous. A representation of the thermal condition of the motor is then developed in response to stimulus current. A comparator then compares the run condition thermal representation with the second thermal threshold value.

Abstract: A system used in a protective relay for motors for transitioning the value of the trip threshold to a motor start (stall) condition. The calculated transition trip threshold value follows I2t, specifically, the current to the motor. The transition trip threshold value includes a small fixed initial (offset) value, so that the increase in the trip threshold during transition to the actual start condition threshold value is always slightly ahead of the increase in the I2t value, preventing a trip until the input current exceeds the final trip threshold for the start condition.

Abstract: A over heat protection circuit for a brushless dc motor includes a thermal sensitive resistor, a resistor and a transistor. The thermal sensitive resistor and the resistor are commonly connected to a base of the transistor while an emitter of the transistor connecting to a motor coil. The thermal sensitive resistor has a resistance value which can be changed in response to an operational temperature. The thermal sensitive resistor is preset to operate at a safety temperature within a predetermined thermal preference. When the operational temperature of the motor coil exceeds the safety temperature, the over heat protection circuit may to cut off a motor current so that the motor coil is protected.

Abstract: A solid state motor protector has a first PTC chip (positive temperature coefficient of resistivity) electrically connected in series relation with a second resistor having a generally fixed temperature coefficient of resistivity and mechanically coupled to the first resistor in close/direct thermal coupling. Another embodiment has a plate like isolator (52) formed with an opening receiving a polymer PTC chip (58) and having terminals (54, 56) which serve as fixed resistors. Yet another embodiment has an additional PTC resistor and a fixed resistor used in a motor reversing mechanism. Still another embodiment has a fixed resistor on either side of a PTC resistor for use in protecting the windings of a single phase motor. Another embodiment has a stack of polymer PTC resistor chips (82a–82d) with one chip serving as a voltage blocking chip and the other chip serving as fixed resistors.

Abstract: In order to determine the temperature in the winding region of an electric motor, especially linear motor, a measuring line made of uniform; electrically conductive material is integrated in a winding, preferably in sections between winding teeth. The measuring line may be configured as insulated double line which is short-circuited on one side. A change in the resistance value of the measuring line allows conclusion about a temperature change and is easy to ascertain.

Abstract: It is so arranged in a robot as to monitor the over-current state of each motor and that of two more than two motors when put together by seeing the total current value of the motors being monitored in parallel with absorption of both the static load torque and the dynamic load torque of each actuator/motor. Additionally, it is so arranged as to check if each of the predetermined unit members including the arm sections and the leg sections of the robot is in an over-current state or not and also if the entire robot is in an over-current state or not, while each of the motors are not in an over-current state.

Abstract: Temperature of the disk drive is measured using components of the disk drive without the need of including a separate temperature sensor to optimize performance of the spindle motor during startup. To measure temperature, the resistance of the VCM winding is measured and used to estimate the spindle bearing temperature. Back emf is measured from VCM windings and used during startup to accurately determine actuator position. Because the VCM coil resistance varies significantly with temperature, coil resistance variations with temperature are determined to enable compensation for inaccuracies in determination of actuator velocity. This inferred temperature is then used to optimize the start up procedure for the spindle motor to accommodate the increased frictional loading of the spindle bearing. In this way an improved performance in the reliability and spin up operation time can be realized without the addition of a separate temperature measurement hardware element.

Abstract: A method and an apparatus for protecting an engine starter of a motor vehicle against overheating with enhanced reliability by controlling turn-on/off of the starter in dependence on a conducting current of the starter, a starter temperature and an ambient temperature. The apparatus includes a voltage detecting system (1) for measuring a supply voltage (Vs) of the engine starter, a voltage waveform information detecting system (11) for detecting at least one of frequency information and amplitude information of a waveform representing variation of the supply voltage (Vs) as voltage waveform information (T), an a conduction time control system (12, 12A) for controlling a conduction time period of the engine starter in accordance with the voltage waveform information (T).

Abstract: A protective device includes a signal input intended for connection to a sensor, a signal output intended for connection to an evaluation unit, and an isolation element for galvanically separating the signal input from the signal output. The provision of the protective device prevents a transmission of overvoltages from the sensor to the evaluating unit.

Abstract: A thermally suppressing circuit includes a restart-charging drive member, a coil set, a restart-charging capacitor, and a charging switch set. The restart-charging drive member is electrically connected to the coil set and the restart-charging capacitor while the charging switch set is connected between the coil set and the restart-charging capacitor. The charging switch set is used to access signals output from the restart-charging drive member. In abnormal operation, as the restart-charging drive member may turn on an auto-restart function to output a high or low voltage signal, the charging switch set is turned on to accelerate charging the restart-charging capacitor to thereby avoid overcurrent passing the coil set.

Abstract: A system for monitoring the temperature prevailing in the stator unit of an electric drive includes a temperature sensor that is integrated into the windings of the stator unit and that transmits a temperature-dependent sensor signal. The sensor signal may be injected via an electrical transmitter unit into the signal processing unit of a position measuring device connected to the drive.

Abstract: An electric motor control unit mounted in an automotive vehicle having a motor that is variable in its rotational speed. A temperature sensing element is arranged to contact a busbar so that relays permit switching operation in response to detection of abnormal heat generation. This controls an electrical power supply to the motor to decrease the rotational speed of the motor without complete stopping of the motor. The rotational speed of the motor returns to a normal speed from the decreased speed by switching operation of the relays with diminishing of the abnormal heat generation.

Abstract: A motor controller system comprises solid state switches for connection between an AC line and motor terminals for controlling application of AC power to the motor. A user input elements selects a current imbalance parameter. Current sensors sense current in each winding of the motor. A control circuit controls operation of the solid state switches. The control circuit compares the sensed currents with the selected imbalance parameter to determine if a fault condition exists.

Abstract: The invention provides means of limiting maximum current conducted through windings of an electric machine having a rotor and a stator. By encouraging an appropriate leakage flux around a winding, a leak impedance can be achieved which may be used, according to the invention, to limit the maximum current in the winding as a matter of machine design.

Abstract: A thermally suppressing circuit mainly comprises a restart-discharging drive member, a coil set, a restart-discharging capacitor, and a discharging switch set. The restart-discharging drive member is electrically connected to the coil set and the restart-discharging capacitor while the discharging switch set connected between the coil set and the restart-discharging capacitor. The discharging switch set is used to access signals output from the restart-discharging drive member. In abnormal operation, as the restart-discharging drive member may turn on an auto-restart function to output a high or low voltage signal, the discharging switch set is turned on to accelerate discharging the restart-discharging capacitor to thereby avoid overcurrent passing the coil set.

Abstract: A method for monitoring thermal overload of an electric load element in a motor vehicle containing other electric consumers, which can be switched into a stand-by phase is disclosed. The load element is monitored by a control device using a calculated load temperature parameter. During a first operational phase, a power loss of the load element or a quantity that is essentially proportional thereto is evaluated for calculating the load temperature parameter. During one or more stand-by phases, the control device is switched with essentially no current between the first operational phase and a second operational phase. After the control device is switched on in the second operational phase, at least one quantity, which is characteristic for the moment of switching on, is evaluated for calculating the existing load temperature parameter.

Abstract: A system and method for controlling an electric motor using real time predictions of motor capability based on thermal modeling and measurements is provided. The invention includes controllers for receiving and processing system input signals, strategies for: determining a maximum energy amount that can be put into the motor before the motor reaches a maximum allowable temperature; determining a motor power assist value that the motor can provide in a predetermined period of time before the motor reaches the maximum allowable temperature; determining a battery power assist value; determining a maximum power assist value that is the minimum of the motor power assist value and the battery power assist value; and comparing the maximum power assist value to a driver demand signal. Strategy outputs can be sent to a vehicle system controller and/or a power assist gauge.