Abstract: A hard start capacitor replacement unit has a plurality of capacitors in a container sized to fit in existing hard start capacitor space. The capacitors are 4 metallized film capacitors wound in a single cylindrical capacitive element. The container has a common terminal and capacitors value terminals for the plurality of capacitors, which may be connected singly or in combination to provide a selected capacitance. An electronic or other relay connects the selected capacitance in parallel with a motor run capacitor. The hard start capacitor replacement unit is thereby adapted to replace a wide variety of hard start capacitors.

Abstract: A method for AC-charging an intelligent battery pack, which is connected to a charging column and has at least two battery modules, which each comprise at least one energy storage element and at least two power semiconductor switches, which interconnect the respective battery module in series or in parallel with another battery module. The battery pack is connected for charging with alternating current provided by the charging column by a charging circuit, which includes a filter and a rectifier. According to the method, a state of each individual energy storage element is monitored. In accordance with a continued evaluation of the states of the respective energy storage elements, a terminal voltage of the battery pack is adjusted by way of dynamic actuation of the power semiconductor switches to a voltage provided by the rectifier.

Abstract: A rotary-machine control device includes: a connection switching device switching a connection state of stator windings of a rotary machine; a current detection unit detecting a rotary machine current flowing in the rotary machine; a voltage application unit applying voltage to the rotary machine; a control unit generating a voltage command provided to the voltage application unit and outputting a switching command to switch the connection state to the connection switching device; and an open-phase determination unit determining presence or absence of disconnection in the rotary machine or presence or absence of disconnection of a power distribution line to the rotary machine. During rotation of the rotary machine, the control unit outputs the switching command and the open-phase determination unit determines presence or absence of disconnection.

Abstract: A system for the resilience of an electric submersible pumping system to a transient power interruption includes a power backup connected to the variable speed drive of the pumping system. A method for controlling the electric submersible pump during the transient power interruption includes connecting a variable speed drive to a power source, charging one or more rechargeable batteries within the power backup, and connecting the power backup to the variable speed drive. The method continues with the steps of operating the motor with the variable speed drive, detecting a disruption in AC power from the power source to the variable speed drive, and applying power from the power backup to the variable speed drive to operate the motor during the transient interruption in electrical power.

Abstract: An operation controlling apparatus of a reciprocating compressor includes: a detector configured to detect a torque output by a motor of the reciprocating compressor, a rotation speed of the motor, a counter electromotive voltage of the motor, and a current applied to the motor; a controller configured to determine a mode switching time point for switching an operation mode of the reciprocating compressor based on the torque, the rotation speed, the counter electromotive voltage, and the current of the motor, and output a control signal for changing a wire ratio of the motor corresponding to the operation mode; and a driver configured to change the wire ratio of the motor based on the control signal and operate the reciprocating compressor in the operation mode among at least two operation modes.

Abstract: An arc quenching device, which is highly reliable, small-sized, and inexpensive, includes: a semiconductor switch connected in parallel to a first switch which is mechanical; a constant voltage circuit configured to use a voltage which is generated between both contact points of the first switch to output a voltage which causes the semiconductor switch to turn on; and a second timer circuit configured to cause the semiconductor switch to turn off after a predetermined time has elapsed since the semiconductor switch turned on.

Abstract: A power supply apparatus (such as an air conditioner) may have a power saving function. A first power supply unit may be connected to an AC power supply and a first communication unit may be connected to the first power supply unit and to a communication line. A connector may be connected to the first communication unit and the communication line. A first controller may be connected to the first communication unit and the connector. A second communication unit may have one side connected to the communication line and the other side connected to the AC power supply. A second power supply unit may be connected to the AC power supply. A wakeup voltage generator may be connected to the communication line and the second power supply unit to generate a voltage. A second controller may be connected to the second communication unit and the wakeup voltage generator.

Abstract: A washing machine includes: a drum that rotates with a washing or drying object contained in the drum; a motor that rotationally drives the drum; a controller that controls rotation of the motor; and an electric current measurer that measures an electric current value representing an electric current flowing in the motor. The controller controls the rotation of the motor to rotate the drum less than one turn, and in accordance with the measured electric current value, detects whether a foreign object that is different from the object and whose mass is greater than an expected mass of the object is inside the drum. In a case where the controller detects the foreign object, the controller stops operation of the washing machine.

Abstract: A portable ride-through (RT) tester provides a voltage drop at control circuitry of a motor starter to test its RT capabilities. The RT tester includes a variable transformer for manually controlling the magnitude of the voltage drop. Timing circuitry is programmed to count cycles of a 120 VAC input voltage to affect the occurrence and duration of the voltage drop. The primary windings of the transformer are connected to the 120 VAC. The variable secondary winding is connected to output terminals, which are electrically connected to the starter control circuitry via conductive probes. The power circuit of the starter is disengaged during testing. The timers sequentially provide the 120 VAC input voltage and the voltage drop at the starter control circuitry. Repeated testing at different durations and monitoring for tripping of relays/solenoids of the starter enables the tester to determine the exact ride-through capability of the motor starter.

Abstract: The present invention relates to a wind turbine with an electrical machine wherein said electrical machine comprises a stator (702) with one or more electrical winding(s) (704), said electrical winding(s) being arranged to be connected to an electrical grid (760) by at least one cable (740) with at least one phase conductor (746), the at least one cable (740) comprises at least one return path (744) to conduct leakage currents, and at least one electrical shield (745), the stator being electrically isolated from a stator housing (701). The invention also relates to a method for minimizing stray currents in an electrical machine in a wind turbine.

Abstract: Provided is a current measuring device including a first wire member formed of a conductive metal and a second wire member formed of a conductive metal, the second wire member partially including a resistive element metal, in which the first wire member and the second wire member are arranged in parallel with an insulator sandwiched therebetween in a portion where at least the resistive element metal is present.

Abstract: A blower motor is provided for use in a machine. The motor includes a stator and a rotor rotatable about an axis. The stator includes a generally toroidal core, a first-main winding, and an auxiliary winding that is electrically out of phase with the first-main winding. The first-main winding and the auxiliary winding are both full pitch windings.

Abstract: A brake device for an AC generator, whose speed can be flexibly controlled, and can function properly even when functions of the control unit are lost.

Abstract: A controller for a drive motor (60) of a product conveyor belt at a checkout has a phase-start cutting and/or phase-end cutting controller (50) that controls the drive motor (60) in such a manner that the product conveyor belt is accelerated with reduced torque from a non-driven state. A start controller controls the drive motor (60) in such a manner that the drive motor (60) initially drives with a non-reduced torque when accelerating the product conveyor belt from the non-driven state before the phase-start cutting and/or phase-end cutting controller (50) further accelerates the product conveyor belt with reduced torque.

Abstract: An apparatus for controlling a fluid pump for a motor vehicle includes: a first controller configured to actuate an electric prime mover of the fluid pump by impressing at least one motor current with an adapted current intensity and an adapted waveform; and a second controller configured to detect a rotational speed of the electric prime mover and to apply an adapted voltage to the electric prime mover on the basis of the detected rotational speed.

Abstract: A motor starter includes: a motor circuit breaker which has an electronic tripping device; a contactor which is correspondingly interconnected to the motor circuit breaker for forming the motor starter; and at least one control line disposed between the motor circuit breaker and the contactor, via which control line a control signal, which is generated depending upon a switching signal for switching the contactor, is transmitted from the contactor to the electronic tripping device. The electronic tripping device generates a tripping signal for switching off a current flow across the switching contact or switching contacts of the motor circuit breaker, depending upon the control signal and current flow across one or more switching contacts of the motor circuit breaker.

Abstract: Provided are a charging rate leveling device and a power supply system including the charging rate leveling device capable of leveling more quickly a charging rate of a plurality of battery cells a battery pack includes. In the power supply system a controlling device includes a two-way DC/DC convertor connected to an auxiliary battery separated from the battery pack, a switch array capable of selectively connecting each of the plurality of auxiliary battery cells the battery pack includes to the two-way DC/DC convertor, so as to charge the battery cell with electric power of the auxiliary battery, and a controller controlling the switch array to connect the lowest voltage battery cell selected among the plurality of battery cells, so as to reduce a difference between charging rates SOC of each of the plurality of battery cells.

Abstract: Device for operating an electric motor, comprising a detection unit for detecting zero-crossings and phase angles of applied phase-shifted sinusoidal voltage phases of a multi-phase power supply network; and a switching unit for connecting half-waves of the applied sinusoidal voltage phases through by means of semiconductor switches in accordance with switching patterns applied to the semiconductor switches, said patterns being synchronised with the detected phase angles and zero-crossings, to generate phase-shifted quasi-sinusoidal voltage phases which are applied directly to the electric motor.

Abstract: A power converting apparatus for applying to a load an alternating-current voltage converted from a direct-current voltage includes an inverter that receives a PWM signal and applies the alternating-current voltage to the load and an inverter control unit that generates the PWM signal and supplies the PWM signal to the inverter. The frequency of the PWM signal is an integer multiple of the frequency of the alternating-current voltage. The alternating-current voltage includes a plurality of positive pulses and a plurality of negative pulses in one cycle of the alternating-current voltage. The number of the positive pulses and the number of the negative pulses are equal.

Abstract: A welding system monitors the changes in the power output provided from a power supply to a device to determine the inductance of power cables between the power supply and the device. The device may determine the inductance of the power cables based at least in part on a delay in a threshold change in voltage to the device after a change in the current demand of the device, a delay in the initialization of the change in the current demand of the device after an initialization signal, a rate of change of the current drawn by the device, or a relative comparison of the voltage to the device and the current drawn by the device, or any combination thereof. If the inductance of the power cables is greater than a threshold inductance, the device may signal the user, disable operation of the device, or any combination thereof.

Abstract: A solar pump system comprises a solar module configured to generate DC power from sunlight, a water pump, an inverter configured to convert the DC power into AC power in order to drive the water pump, and a controller configured to generate a control signal for controlling an output frequency of the AC power. The controller compares the DC link voltage with a first reference level, adjusts the output frequency of the AC power, if the DC link voltage is greater than the first reference level, and determines the output frequency to prevent the DC link voltage from being equal to or less than a second reference level, if the DC link voltage is less than the first reference level.

Abstract: A diagnosis circuit comprises: a logic circuit, wherein the logic circuit comprises a set having a gate voltage terminal of an arm of a phase logical OR a dead time voltage terminal, and the set logical XOR a drain-source voltage terminal of another arm of the phase; a filter circuit coupled to the logic circuit, wherein the filter circuit is configured to filter transient noises; a comparison circuit coupled to the filter circuit, wherein the comparison circuit is configured to determine whether a phase current of a phase current terminal of the phase is greater than zero; and a latch coupled to the comparison circuit, wherein the latch is configured to store diagnosis signals temporarily.

Abstract: An on-board trimming circuit suitable for trimming an accelerometer provides offset trim and gain trim modules for determining correct trim codes for subsequent programming into the trimming circuit. The correct trim codes may be determined by comparing sensor outputs which have been adjusted by successive trim codes, with a reference voltage in a comparator until the comparator toggles or by using a successive approximation technique. The reference voltage is supplied form a tap of a feedback resistance divider circuit which forms a part of an on-board voltage reference generator which may be used to provide a full scale reference for an analog to digital converter which converts a sensor output voltage into a digital signal. Using these reference voltages significantly lessens the impact of any offsets inherent in the voltage reference generator on the trimming process.

Abstract: A machine learning apparatus that learns a condition associated with a gain of a magnetic flux controller and a time constant of a magnetic flux estimator in a motor control apparatus includes: a state observation unit that observes a state variable defined by at least one of data relating to an acceleration of a motor, data relating to a jerk of the motor, and data relating to an acceleration time of the motor; and a learning unit that learns the condition associated with the gain of the magnetic flux controller and the time constant of the magnetic flux estimator in accordance with a training data set defined by the state variable.

Abstract: A variable speed electric drive for use in refrigerant systems includes an electric motor for driving an associated component at a variable speed that is a function of an operating frequency of the motor; and a control for supplying alternating discrete drive frequencies to the electric motor to provide a continuously variable speed drive of the associated component. The control cycles the drive frequency to the electric motor among the at least two discrete frequencies so that the variable average resultant speed at which the associated component is driven is a function of a combination of the selected at least two discrete frequencies.

Abstract: A power conversion apparatus includes power conversion circuitry that converts first power supplied from a power source into AC power corresponding to second power of a power system, and control circuitry that instructs, at a time that is determined based on a voltage across a capacitor disposed between the power system and the power conversion circuitry, the power conversion circuitry to start applying an AC voltage to the capacitor.

Abstract: A method including: determining a cooling value; and comparing the cooling value to an activation point of a lead compressor. The lead compressor is in a tandem set of scroll compressors of a cooling system. The tandem set of compressors comprises a lag compressor. The method further includes: activating the lead compressor when the cooling value is greater than the activation point; activating the lag compressor subsequent to activating the lead compressor; and determining whether conditions exist including: an alarm associated with the lag compressor being generated, and the lead compressor being deactivated. The method further includes deactivating the lag compressor when at least one of the conditions exists in the cooling system.

Abstract: An air conditioner and a compressor protection circuit thereof are provided. When overcurrent occurs in a phase current of a compressor, an overcurrent level signal is output by a voltage comparison module, and is latched and output to an intelligent power module by a signal latching module, and the intelligent power module shuts off the output of the phase current according to the overcurrent level signal, so as to achieve the overcurrent protection of the compressor; and subsequently, a conventional level signal is output to the signal latching module by the voltage comparison module, the signal latching module keeps outputting the overcurrent level signal, and outputs the conventional level signal until a latching cancel signal output by a signal processing circuit is received, so that the intelligent power module starts the output of the phase current, thereby enabling the compressor to normally operate.

Abstract: A control system for controlling an electric rotating machine includes an inverter for driving the electric rotating machine, a converter that converts an input voltage thereof to an output voltage equal to a step-up command value, and supplies the output voltage to the inverter, a pulse generation section that generates PWM pulses from a carrier for controlling the inverter in accordance with result of comparison between the carrier and a voltage command to the electric rotating machine, and a command generation section that generates the step-up command value. The command generation section includes a command control section that controls the step-up command value such that a modulation factor defined as an amplitude of the voltage command divided by the output voltage of the converter is changed within a predetermined modulation factor range.

Abstract: Disclosed herein is an apparatus for controlling an inverter in an inverter system. The apparatus includes: a first determining unit to determine a magnitude, a phase and a frequency of an input voltage to an electric motor in the inverter system; and a second determining unit to determine a restart command voltage for generating an inverter driving voltage larger than a residual voltage in the electric motor using the magnitude of the input voltage determined by the first determining unit, when the inverter system is restarted.

Abstract: The invention relates to a method of starting an electric motor (10) powered by an alternating power supply voltage, said method consisting of supplying current to the motor (10) with a delay tret, during each period of the power supply voltage. The starting method comprises a first sequence in which the following steps are carried out during each nth period of the power supply voltage, where n is an integer number greater than 0: a) determine the value of a variation of a resistance of the electric motor during the previous n periods of the power supply voltage; b) compare said value of the variation of the determined motor resistance with a first threshold resistance value; c) if the value of the variation of the motor resistance is less than the first threshold value, reduce tret. The invention also relates to a starter device and a computer program.

Abstract: Disclosed herein is an apparatus for controlling an inverter. The apparatus determines the phase of an command voltage in a restart section taking into account the frequency of an input voltage to an electric motor when an input power is reduced below a rated power, the frequency of the input voltage into the electric motor at the time of restarting, a time period for generating a torque, and the phase of the input voltage to the electric motor at the time of the restarting.

Abstract: The dynamic system is part of a dynamic apparatus having at least one photovoltaic generator, at least one battery and at least one device for controlling the dynamic apparatus. The method for controlling the dynamic system on the basis of sunlight involves electrically isolating the photovoltaic generator from the battery, reading the no-load voltage of the photovoltaic generator, determining a numerical value on the basis of the no load voltage, corresponding to the no-load voltage reading, and comparing the predetermined numerical value with at least one reference threshold value. When the predetermined numerical value corresponds to a value range limited by at least one such reference threshold value the dynamic system is controlled so as to thereon confer a configuration corresponding to the value range.

Abstract: An apparatus includes a switch module that selectively turns on a switch to connect an input power conductor connected to a voltage source to a motor in a sequence. The switch for each phase is turned on for a portion of a cycle of a fundamental frequency of the voltage source. A source phase module determines a phase of the AC voltage source, a back-EMF phase module determines a phase of a back-EMF of the motor, and a torque module determines when a phase difference between the phase of the AC voltage source and the phase of the back-EMF is within a phase range indicative of a positive motor torque. A pulse module enables the switches in response to the phase difference having a phase within the phase range and disables the switches in response to the phase difference having a phase not in the phase range.

Abstract: A motor control apparatus includes a voltage regulator to execute a voltage increase mode to increase a voltage applied to an induction motor from a lower limit of a first range over time. A frequency regulator executes a frequency decrease mode to decrease a frequency of the voltage from an upper limit of a second range over time. The frequency regulator limits decrease of the frequency when a bus voltage of a bus exceeds a first threshold in the frequency decrease mode. The bus supplies DC power to an inverter to drive the motor. A mode changer alternatively changes the voltage increase mode and the frequency decrease mode to control the motor to change from a free running state to a state in which the voltage and the frequency satisfy a relationship. The determinator determines whether the voltage and the frequency satisfy the relationship.

Abstract: A control method of a radiation tomographic imaging apparatus having a gantry rotating section equipped with a radiation tube including a liquid bearing and a rotor configured to support an anode and configured to rotate is provided. The control method includes a control step that is configured to start a rotation of the gantry rotating section at a second velocity slower than a first velocity, start control for stopping the rotation of the rotor, and control the gantry rotating section and the radiation tube so as to stop the gantry rotating section at a home position. The control method further includes a setting step configured to set at least one of the second velocity and the delay time such that a rotational angular position of the gantry rotating section at a time that the rotor stops rotation averagely varies when a shutdown is performed plural times.

Abstract: A generator for providing regulated current signals, to terminals of a load includes: a plurality of secondary stages, including a direct voltage source insulated from those of other stages, connected in series between the midpoint of the second half-bridge of each secondary stage and the midpoint of the first half-bridge of the next secondary stage, the load terminals being respectively connected to the midpoint of the first half-bridge of a first secondary stage, and to the midpoint of the second half-bridge of a last secondary stage; and a control circuit capable of: selecting a group of secondary active stages, and at least one regulating stage; simultaneously controlling each active stage, except the regulating stage, at the frequency of the current slots; controlling the regulating stage according to a frequency higher than the previous one; and controlling the switches of the non-selected secondary stages to insulate their voltage source.

Abstract: An illumination device includes a light emitting unit; and a lighting circuit, to which the light emitting unit is installed, for supplying an output voltage to the light emitting unit. The light emitting unit includes a light emitting element which is connected to an output terminal of the lighting circuit and emits light by the output voltage supplied from the lighting circuit; and a current limiting unit which limits a current flowing into the light emitting element portion from the lighting circuit at the time when the light emitting unit is installed to the lighting circuit.

Abstract: A method of operating a refrigeration system that receives power from an electrical grid includes operating at least one component of the refrigeration system in a first state. The method includes detecting a fault event of the electrical grid in response to a concurrent increase in amount of current drawn by the component and decrease in voltage of power received by the component. The method includes, in response to detecting the fault event, switching the component from the first state to a second state, wherein the component consumes less power in the second state than in the first state. The method includes determining a first delay period according to a random process. The method includes identifying a conclusion of the fault event. The method includes, in response to the conclusion of the fault event, waiting for the first delay period before switching the component back to the first state.

Abstract: An electrical drive system includes an electric motor having an armature, which is mounted on a stator, and a rotor, wherein aligning stator flux with rotor flux enables current to flow in the armature without inducing torque on the rotor shaft. The disclosed operation may be used, for example, in testing the electrical drive system. The electric drive system can carry full rated current yet produce little or no torque, thereby increasing the current that can be tested during electrical drive test procedures without producing undesired forces or motion. The method may be used, for example, in heating the electric motor, for example for de-icing.

Abstract: An electronic overload relay includes a microcontroller having an internal random-access memory (RAM) in which a motor thermal model is stored. The microcontroller is coupled to a power supply having a bulk storage capacitor. In response to a trip or stop condition of a protected motor, the thermal model is maintained in the RAM with no timing or decrementing. When the motor restarts, the microcontroller calculates a change in capacitor voltage to estimate the motor stop duration. The thermal model is decremented based on the estimated duration.

Abstract: An embodiment of the invention provides an AC motor that is driven by an AC voltage. The AC motor includes a motor coil, a switch circuit, a position detector and a controller. The motor coil receives the AC voltage to drive an axis of the motor. The switch circuit is coupled to the motor coil and controls a current passing through the motor coil. The position detector detects the position of a motor rotor to output a polarity signal. The controller controls the switch circuit according to the polarity signal and the AC voltage to make the current to be a first current with a first direction or a second current with a second direction.

Abstract: A crankcase heating control system for a heat pump system includes a data receiving module and a power control module. The data receiving module receives data indicative of a temperature of a compressor of the heat pump system, data indicative of an ambient temperature, and data indicative of a current date and a current time. The power control module selectively applies power to a heater of a crankcase of the compressor and selectively disables the heater based on the temperature of the compressor, the ambient temperature, the current date, and the current time.

Abstract: A system and method for automatically defining and tuning operating parameters for a motor control device with minimal or no operator input is disclosed. The system includes a motor control device electrically connectable to an AC motor and a controller that is programmed to define a motor start-up function based on a rated current of the motor, the motor start-up function comprising an initial torque factor and an initial ramp time. The controller also triggers switching devices of the motor according to the motor start-up function to inject current into the motor during a first trial run, monitors operating conditions of the motor and motor control device during the first trial run, modifies the motor start-up function based on the monitored operating conditions, and triggers the plurality of switching devices according to the modified motor start-up function to inject current into the motor during a subsequent trial run.

Abstract: At least one example embodiment discloses a drive system including a motor including a rotor, the motor configured to receive a measured current, a controller configured to generate a voltage command for the motor, a sliding mode observer configured to determine an estimated current for the motor based on the voltage command, determine a difference between the measured current and the estimated current, and determine a switching control vector and an estimator configured to estimate a rotor position based on the switching control vector, the switching control vector being determined based on the difference and adaptive parameters of the sliding mode observer, the controller being further configured to control the motor based at least in part on the estimated rotor position.

Abstract: A control device for an electric motor of a cooling fan for the radiator of a motor vehicle has a control transistor connected to the motor, and an electronic control unit for controlling the speed of the motor. The control unit controls the transistor in such a manner as to limit the current flowing in the motor to a predetermined value when, by effect of the load conditions of the motor and the voltage applied to the motor, the current in the motor tends to exceed the predetermined value.

Abstract: Controlling a synchronous electric machine includes determining a rotor field current of a wound rotor of the synchronous electric machine and determining a time-rate change in field flux linkage. A rotor field voltage is determined based upon the time-rate change in the field flux linkage, and a rotor field resistance is determined based upon the rotor field voltage and the rotor field current. A rotor temperature is determined based upon the rotor field resistance. Operation of the synchronous electric machine is controlled responsive to a torque command and the rotor temperature.

Abstract: A variable-speed hoisting machine uses an electric motor having a pull-rotor brake as a hoisting motor and capable of supplying the electric motor with an electric current that can reliably release the pull-rotor brake at the time of starting an operation even in the case of a variable-speed hoisting machine such as an electric chain block in a variable-speed hoisting machine having an electric motor with a pull-rotor brake and an inverter controlling the speed of the electric motor in a soft-start manner, the inverter is set to operate according to a predetermined voltage-frequency (V-F) pattern.

Abstract: The system and method disclose for the controlling of motor switching. The system includes a controller unit having a control signal generator, a memory device, a processing unit, a signal acquisition device, and an analog-to-digital converter. A power stage has a plurality of switches and receives a control signal from the control signal generator and a power signal from a power source. The power stage drives two windings of the set of three stator windings with a multi-state pulse and leaves one stator of the three stator windings undriven. The processing unit acquires a demodulated measured voltage on the undriven winding. The processing unit communicates with the power stage to change which two windings of the three stator windings are driven when the demodulated measured voltage surpasses a threshold.

Abstract: A motor starter system and a method for operating same are disclosed. According to an embodiment of the present invention, reliability of a motor protection function during an overcurrent is improved by automatically controlling the on/off state of an electromagnetic contactor using an analog sensor value outputted from an external sensor. In addition, the present invention can receive an external sensor value through a connected upper monitoring device, monitor, in real time, the motor starter state, and transmit a control command for directly controlling the on/off state of the electromagnetic contactor, and thus enables excellent operation, integrated lifetime prediction, and motor load management. Furthermore, the present invention can reduce wiring work and a cost thereof and maximizing the use of space more than when controlling the electromagnetic contactor by using the I/O of a PLC.