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301results about How to "Avoid Overvoltage Problems" patented technology
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DC-to-DC converter capable of preventing overvoltage
InactiveUS6028755AAvoid Overvoltage ProblemsAvoid fireEfficient power electronics conversionApparatus without intermediate ac conversionOvervoltageEngineering
To avoid burning out a capacitor in a synchronous rectification type DC-to-DC converter due to overvoltages, the synchronous rectification type DC-to-DC converter includes a storage unit storing therein power derived from a power supply, switching elements connecting and disconnecting respective signal paths from power and ground, and a control unit controlling the connecting / disconnecting operations of the switching elements to maintain a voltage output from the storage unit at a predetermined value. The DC / DC converter also includes an overvoltage detecting unit monitoring a voltage derived from the power supply to thereby output an alarm signal when the voltage derived from the power supply exceeds a preselected voltage value, a shortcircuiting unit influencing the connecting conditions of the switching elements when the alarm signal from the overvoltage detecting unit is input therein, whereby the voltage derived from the power supply is shortcircuited, and an interrupting unit interrupting one of the signal paths by the power shortcircuited by the shortcircuiting unit.
Owner:FUJITSU LTD
Ac light emitting diode
ActiveUS20100117101A1Improve operating characteristicsAvoid Overvoltage ProblemsSolid-state devicesSemiconductor devicesAC powerLight-emitting diode
Owner:SEOUL VIOSYS CO LTD
Solar battery module for optical electrolysis device and optical electrolysis device
InactiveUS6198037B1Avoid Overvoltage ProblemsEasy to separateCellsElectrolysisElectrolysisElectrical battery
Partition member 34 is provided, which partitions the interior of glass container 31 into reduction reaction chamber 32 and oxidation reaction chamber 33 and which is made of a polymer electrolyte that conducts hydrogen ions; solar battery modules 35 are mounted on this partition member 34, for example in a matrix arrangement of five rows and three columns; a solar battery module 35 has a photocell array (photoelectromotive force: 2.0-2.4 V) consisting of four spherical solar battery elements (photoelectromotive force: 0.5-0.6 V) connected in series, anode 46, and cathode 48; solar battery modules 35 are mounted on partition member 34 so that anode 46 is in contact with the electrolyte of oxidation reaction chamber 33 and cathode 48 is in contact with the electrolyte of reduction reaction chamber 32; sunlight is shined on solar battery modules 35, and the photoelectromotive force electrolyzes the water and produces hydrogen gas from cathode 48 and oxygen gas from anode 46.
Owner:SPHELAR POWER
Reactive-power control method of wind power field
ActiveCN102354992ARealize coordinated controlAvoid oscillationSingle network parallel feeding arrangementsReactive power adjustment/elimination/compensationElectricityPower compensation
The invention discloses a reactive-power control method of a wind power field, which is suitable for performing reactive-power coordinated control on a wind power field variable-speed constant-frequency wind power generating set and a reactive-power compensation device. The control method comprises the steps that: reactive-power requirements of the wind power field are calculated, and a correspondent allocation method is adopted according to the valid reactive-power power capacities of the reactive-power compensation device and the wind power generating set. Due to the adoption of the controlmethod, the reactive-power power adjusting capacity of the variable-speed constant-frequency wind power generating set can be adequately played, the coordinated control of multiple reactive power sources can be realized, and the oscillation situation caused by the adjustment can be avoided. When an electric power system has malfunctions, the reactive power adjustment is locked, so the system over-voltage caused by the excessive reactive power of the system after the malfunction is removed can be prevented. When the reactive power capacity of the wind power field is insufficient to maintain the voltage of an interconnected point, a prompting signal is transmitted, the active power of the wind power field is limited, and the coordination of the active power and the reactive power can be realized.
Owner:NORTH CHINA ELECTRIC POWER UNIV (BAODING) +1
Electric locomotive non-power-off neutral section passing-electric energy quality comprehensive compensation device and method
ActiveCN102035212APrevent surgeNo currentPolyphase network asymmetry elimination/reductionReactive power adjustment/elimination/compensationCapacitancePower quality
The invention relates to an electric locomotive non-power-off neutral section passing-electric energy quality comprehensive compensation device and method, which belongs to the technical field of railway transport equipment and electric electronics. The device comprises a controllable transfer switch, a single-phase step down transformer, a single-phase step down transformer with a middle tap, a two-phase back-to-back converter sharing a DC-side capacitor, a circuit breaker switch, four position sensors and three electric quantity sensors. In the method, when the electric locomotive passes the neutral section, the controllable transfer switch is turned off, and the device works in a non-power-off neutral section passing mode to perform control on amplitude and phase of the neutral section voltage and enable the electric locomotive to pass the neutral section with load in a non-power-off manner. Without locomotive passing, the controllable transfer switch is closed, and the device works in an electric energy quality comprehensive compensation mode and has functions of active power transfer as well as inactive power and harmonic compensation. Through the device, the problems relating to electric energy quality of a traction substation and neutral section can be comprehensively solved based on the traditional traction power supply mode.
Owner:TSINGHUA UNIV +1
DC-DC converter with over-voltage protection circuit
InactiveUS20060054601A1Avoid Overvoltage ProblemsIncrease the output voltageElectric discharge tubesEmergency protective circuit arrangementsDc dc converterInductor
There is provided by this invention an apparatus and method of supplying to ignite a plasma wherein in the event of an arc a shunt switch is used to divert the power away from the plasma that is incorporated into an over-voltage protection circuit that controls the shunt switch to act as a boost switch when the arc is extinguished such that the stored inductor energy is used to boost the ignition voltage for reigniting the plasma if it is extinguished. When the arc is extinguished, the inductor current is diminished, and the plasma is ignited, then the switch S1 is turned OFF and the inductor energy goes to the plasma and the power supply operates in its normal operating mode.
Owner:AES GLOBAL HLDG PTE LTD
Light emitting device for ac operation
InactiveUS20100072905A1Reduce manufacturing costAvoid Overvoltage ProblemsElectroluminescent light sourcesSolid-state devicesAC powerLight emitting device
An AC light emitting device is disclosed. The AC light emitting device includes at least four substrates. Serial arrays each of which has a plurality of light emitting cells connected in series are positioned on the substrates, respectively. Meanwhile, first connector means electrically connect the serial arrays formed on respective different substrates. At least two array groups each of which has at least two of the serial arrays connected in series by the first connector means are formed. The at least two array groups are connected in reverse parallel to operate. Accordingly, there is provided an AC light emitting device capable of being driven under an AC power source.
Owner:SEOUL VIOSYS CO LTD
DC-to-DC converter capable of preventing overvoltage
InactiveUS6204648B1Avoid Overvoltage ProblemsAvoid fireEfficient power electronics conversionApparatus without intermediate ac conversionOvervoltageConverters
To avoid burning out a capacitor in a synchronous rectification type DC-to-DC converter due to overvoltages, the synchronous rectification type DC-to-DC converter includes a storage unit storing therein power derived from a power supply, switching elements connecting and disconnecting respective signal paths from power and ground, and a control unit controlling the connecting / disconnecting operations of the switching elements to maintain a voltage output from the storage unit at a predetermined value. The DC / DC converter also includes an overvoltage detecting unit monitoring a voltage derived from the power supply to thereby output an alarm signal when the voltage derived from the power supply exceeds a preselected voltage value, a shortcircuiting unit influencing the connecting conditions of the switching elements when the alarm signal from the overvoltage detecting unit is input therein, whereby the voltage derived from the power supply is shortcircuited, and an interrupting unit interrupting one of the signal paths by the power shortcircuited by the shortcircuiting unit.
Owner:FUJITSU LTD
Method of controlling output of ultrasonic speaker, ultrasonic speaker system, and display device
InactiveUS20070183605A1Easy to changePrevent modulated wavesSignal processingPiezoelectric/electrostrictive transducersFrequency bandCarrier signal
A method of controlling an output of an ultrasonic speaker that reproduces audible-frequency-band signal sounds by modulating carrier waves with audible-frequency-band signal waves output from a signal source and driving an ultrasonic transducer with the modulated waves includes: dividing the audible-frequency-band signal waves into a plurality of frequency bands; separately adjusting amplitudes of the signal waves and amplitudes of the modulated waves in the respective frequency bands; and driving a plurality of ultrasonic transducers provided corresponding to the respective frequency bands with the modulated waves generated corresponding to the respective frequency bands. Band-corresponding volume setting data, which is used to set volume of the ultrasonic transducers corresponding to the respective frequency bands by means of a plurality of band-corresponding volume setting units provided corresponding to the respective frequency bands, and overall volume setting data, which is used to set volume in common with respect to the plurality of ultrasonic transducers by means of an overall volume setting unit, are provided. Gains of modulated wave amplitude adjustment units that adjust the amplitudes of the modulated waves in the respective frequency bands are determined corresponding to the respective frequency bands on the basis of a combination of the band-corresponding volume setting data and the overall volume setting data.
Owner:SEIKO EPSON CORP
Method for varying the power consumption of capacitive loads
ActiveUS7132802B2Avoid Overvoltage ProblemsLife of lamp can be influencedAc-dc conversion without reversalConversion with intermediate conversion to dcDimmerCapacitor
Method for varying the power consumption of capacitive loads, in particular compact fluorescent lamps which are operated using a phase-gating dimmer by a converter (step-up converter). According to the invention, in the case of a nonconducting dimmer (i.e. no system power supply to the load), the switch (T1) in the converter (step-up converter) is closed. In the case of a conducting dimmer (i.e. when a system voltage is applied to the load), the step-up converter operation takes place until a predetermined maximum voltage is reached across the smoothing capacitor of the load.
Owner:ABL IP HLDG
High power motor over-voltage protection device
InactiveCN1885660AEffective protectionReduce damage rateEmergency protective circuit arrangementsTransformerThree-phase
The related over-voltage protector for high-power motor comprises: three ZnO arresters with cathode paralleled together and connected to ground terminal and anode connected to three-phase terminal, three groups of R-C devices with two ends connected to ground terminal and arrester another end respectively. This invention can reduce damage rate of high-power motor and transformer to 2%.
Owner:SHANXI TAIGANG STAINLESS STEEL CO LTD
Electric motor control device
ActiveCN103988419AHighly stable regenerative actionPrevent overcurrentElectronic commutation motor controlAC motor controlCurrent limitingFault current limiter
In the present invention, a current vector control unit, which separately controls a d-axis current and a q-axis current that are obtained from a current of an electric motor by means of orthogonal transformation according to a target command value, is provided, and a drive unit drives the electric motor. Furthermore, a phase angle command generation unit generates a phase angle command ([beta]*) on the basis of the difference ([increment]v*) between the absolute value (|v*|) of a voltage command from the current vector control unit to the drive unit and a predetermined reference value (Vlmt). A d-axis current command generation unit generates a d-axis current command (id*) on the basis of the sine value of the phase angle command ([beta]*). A q-axis current limiter sets a limit value for a q-axis current command (iq*) on the basis of the cosine value of the phase angle command ([beta]*). Due to this configuration, voltage saturation is eliminated, and the electric motor is highly stably driven while producing a high output even when a target command value in access of the possible output limit of the electric motor is input when the voltage is nearly saturated.
Owner:PANASONIC CORP
Charging equipment of portable device
ActiveCN101286646ASimple designReduce power lossBatteries circuit arrangementsElectric powerControl signalControl unit
The invention relates to a charging device for a portable apparatus, which is applied to charging up a battery module of the portable apparatus. The charging device comprises a sensing circuit, a control unit and a linear charging circuit. The sensing circuit detects a sensing signal generated when a power converter is inserted into the portable apparatus and transmits the sensing signal to the control unit; the control unit generates a control signal according to the sensing signal and the electric quantity of the battery module. The charging device of the invention is characterized in that the linear charging circuit receives an output power supply of the sensing circuit and charges up the battery module according to the control signal.
Owner:ACER INC
Driver circuit
ActiveUS20100308888A1Avoid Overvoltage ProblemsIncrease speedPulse automatic controlPulse shapingOvervoltageDriver circuit
A driver circuit including a pre-driver B1 that operates by receiving operating power from a first power supply VDDI, and a main-driver B2 that receives operating power from a second power supply VDDE, amplifies an output signal from the pre-driver B1, and outputs the amplified signal. It also includes a first switch B4 between the first power supply VDDI and the pre-driver B1. It also includes a second switch B5 between the second power supply VDDE and the main-driver B2. A overvoltage protection sequence circuit B3 controls the On / Off states of the first switch B4 and the second switch B5 to controls the On / Off order of the pre-driver B1 and the main-driver B2. By doing so, the overvoltage protection sequence circuit B3 prevent an overvoltage from being applied to the driver circuit, especially to the main-driver B2.
Owner:RENESAS ELECTRONICS CORP
Control apparatus and control method for electric vehicle
ActiveUS20070187158A1Avoid Overvoltage ProblemsReduce torqueHybrid vehiclesDigital data processing detailsElectric vehicleControl equipment
A control apparatus for an electric vehicle includes a road surface condition detection portion, a slip determination portion, a torque reduction device, and a voltage control device. The electric vehicle includes a motor that generates drive power for the electric vehicle, and a drive device that drives the motor. The road surface condition detection portion detects the condition of a road surface on which the electric vehicle is driven. The slip determination portion determines whether the electric vehicle is slipping. The torque reduction device reduces the torque of the motor when the slip determination portion determines that the electric vehicle is slipping. The voltage control device controls a voltage input to the drive device to reduce the voltage when the road surface condition detection portion determines that the road surface has a friction coefficient lower than a predetermined value.
Owner:TOYOTA JIDOSHA KK +1
Power factor correction circuit and driving method thereof
ActiveUS20110095732A1Minimize impactSlow response of controlAc-dc conversion without reversalConversion with intermediate conversion to dcControl switchPower factor correction circuits
The present invention relates to a power factor correction circuit and a driving method thereof.The power factor correction circuit receives an input voltage and maintains an output voltage at a constant level by controlling switching operation of a power switch connected to an inductor that supplies the output voltage. In this case, the power factor correction circuit controls switching operation of the power switch by differentiating a control structure for an output voltage respectively according to a stabilization period during which the output voltage is constantly maintained and a start-up period during which the output voltage is increased before being stabilized. In addition, the power factor correction circuit controls the switching operation of the power switch according to the control structure of the start-up period during a predetermined correction delay period from a time that the stabilization period starts.
Owner:SEMICON COMPONENTS IND LLC
Circuit breaker with hybrid switch
ActiveCN105493218AReduce heat dissipationAvoid Overvoltage ProblemsElectric switchesArrangements responsive to excess currentDc circuit breakerAlternating current
Alternating current circuit breaker with a first galvanic separation switch (SW2) and a bypass switch (SW1) in a live line, and a second galvanic separation switch (SW3) in a neutral line, and a semiconductor switch element connected parallel to the bypass switch (SW1). The semiconductor switch element comprises a combination of a rectifier bridge (D1-D4) and an isolated gate bipolar transistor (IGBT). A processing unit is connected to a current measurement unit arranged in the live line, and is arranged to control the bypass switch (SW1), first and second galvanic separation switches (SW2, SW3) and the conducting state of the isolated gate bipolar transistor (IGBT) in case of detection of a short circuit condition.
Owner:EATON IND NETHERLANDS
Voltage measurement apparatus and electrically-driven tool
InactiveUS7592774B2Avoid Overvoltage ProblemsNarrowing voltageBatteries circuit arrangementsMaterial analysis by electric/magnetic meansElectricityCapacitance
Owner:PANASONIC CORP
Mixed type three-pole direct current power transmission system and control method thereof
InactiveCN103401263AReduce overvoltageInhibit currentElectric power transfer ac networkThree-or-more-wire dc circuitsOvervoltageHybrid type
Owner:ZHEJIANG UNIV
Power conversion device and power generation conversion system
ActiveCN101534014AProtection against overvoltageImprove operational continuitySingle network parallel feeding arrangementsWind motor combinationsVoltage amplitudeCalculator
The invention provides a power conversion device outputting the power generated by power source to the AC system and capable of improving the operation continuity of the AC system when the voltage decreasing. The power conversion device has an electric power converter (11) with one end connected to the AC system (2), the other end connected to the power source (3) for controlling the power generation of the generator; an electric power converter (10) for controlling the power outputted to the AC system; and a control portion (200) for controlling the electric power converter (10). An amplitude calculator (2001) calculates the voltage from the AC system, and executing current conversion to the voltage amplitude; an amplitude limiter (2005) limits the upper limit of power generated by the power source (3). A maximum power operation controller (20040 outputs the DC current and panel voltage and searches the current instruction value Idcref for executing maximum power operation. The current instruction value Idcref is limited between 0 to the upper limit, obtaining the different with IdcrefN DC current; the voltage instruction value Vchop is obtained by a current controller (2007) for outputting to the electric power converter (11).
Owner:HITACHI LTD
Apparatus and method for dc/ac systems to ride through grid transients
ActiveUS20110128760A1Avoid Overvoltage ProblemsHigh voltageConversion with intermediate conversion to dcEmergency protective circuit arrangementsOvervoltagePower grid
A converter system comprises a DC to AC converter, a maximum power point tracking device, and an array-side control. The DC link converts DC from a photovoltaic array to AC for a grid. The maximum power point tracking device is coupled to the array. The array-side control, which is coupled to the DC to AC converter and the device, prevents overvoltage in the DC bus of the DC to AC converter using array voltage and current data from the device and DC bus voltage data from the DC to AC converter during a grid transient by adjusting a maximum power point of the array to increase array voltage.
Owner:GENERAL ELECTRIC CO
Starting method for flexible direct current transmission system
InactiveCN103066615AProtection against overvoltageSuppresses AC overcurrentElectric power transfer ac networkAc-dc conversionTransmission systemTransverter
The invention discloses a starting method for a flexible direct current transmission system. The flexible direct current transmission system comprises a two-end or multi-end voltage source transverter connected by aid of a direct-current circuit, a direct current side of the voltage source transverter is connected with an isolation knife switch, and an alternating current side is connected with a wire-inlet switch through a group of charging resistors and a bypass switch which are in parallel connection. The starting method comprises the following steps that the transverter is in electrode connection, the transverter is charged, a fixed direct current voltage control transverter reduces voltage and unlocks, direct current voltage is established; a non-direct-current voltage control transverter unlocks; and after unlocking is finished, direct current voltage instructions of the fixed direct current voltage control transverter enable voltage to be increased to a rated value according to set increasing and decreasing rate. The method can void overvoltage caused by controller overshooting in the unlocking process of the fixed direct current voltage control transverter, effectigvley supresses alternating current over-current generated during unlocking of the fixed direct current voltage control transverter, and effectively suppresses alternating and direct current overcurrent generated during the unlocking process of the non-fixed direct current voltage control transverter.
Owner:NR ELECTRIC CO LTD +1
Open-circuit protection circuit
ActiveCN101820710AAvoid Overvoltage ProblemsLow costElectric light circuit arrangementEmergency protective arrangements for limiting excess voltage/currentLoad circuitDriver circuit
The invention discloses an open-circuit protection circuit, which comprises two branch load circuits of a constant-current driving circuit, a voltage stabilizing unit, an open-circuit detection unit and a short circuit unit. Two connection ends of the voltage stabilizing unit are connected with the two ends, with the same polarity, of the two branch load circuits; the other ends, with the same polarity, of the two branch load circuits have equal potential; the two ends, with the same polarity, of the two branch load circuits are also connected with two input ends of the open-circuit detectionunit respectively; and the output end of the open-circuit detection unit is connected with a control end of the short circuit unit. The open-circuit protection circuit has the advantages of low realization cost and wider application range.
Owner:INVENTRONICS HANGZHOU
Vehicle-mounted power generator set
InactiveUS20060103239A1Prevent rotation speedReduce speedAnalogue computers for vehiclesElectrical controlElectric forceVehicle driving
A vehicle-mounted power generator set including: an AC generator driven by an engine of a vehicle; an electric power conversion portion that converts an output of the AC generator into an AC output having commercial frequency; a controller having electric power conversion portion control means for controlling the conversion portion to generate an AC output having commercial frequency when a control mode is a power generation mode, and engine control means for controlling the engine to rotate at a rotational speed suitable for supplying electric power from the conversion portion to a load when the control mode is the power generation mode and controlling the engine to be suitable for driving the vehicle when the control mode is the vehicle driving mode; and a control switch inserted between each output terminal of the AC generator and each input terminal of the electric power conversion portion, and controlled to be in an ON state when the control mode is the power generation mode and in an OFF state when the control mode is the vehicle driving mode.
Owner:KOKUSAN DENKI CO LTD
Hybrid back-to-back direct-current power transmission device and fault processing method
ActiveCN105391032AAvoid Overvoltage ProblemsEffectively handle AC failuresElectric power transfer ac networkEmergency protective circuit arrangementsOvervoltageCapacitance
The invention discloses a hybrid back-to-back direct-current power transmission device and a fault processing method. The method comprises the following steps of: 1, collecting a direct voltage and a direct current of the direct-current power transmission device, an alternating voltage of an alternating power grid connected with a voltage source type converter, and a voltage of a voltage source type converter sub-module capacitor; 2, judging whether the direct-current power transmission device breaks down according to analog quantities collected in the step 1; and 3, if yes, changing the power transmitted by the voltage source type converter, and simultaneously changing the direct voltage generated by the voltage source type converter and / or the output alternating current. According to the invention, the direct current overvoltage problem caused when the alternating power grid connected with voltage source type converter at an inversion side in the direct-current power transmission device can be effectively solved, a direct-current bus and the sub-module capacitor are prevented against the overvoltage, the alternating fault is reliably crossed, and the safety of equipment is better protected.
Owner:NR ELECTRIC CO LTD +1
DC power grid line fault protection method
ActiveCN106936120AGood effectRapid isolationEmergency protection detectionMeasurement pointDc circuit breaker
The invention relates to a DC power grid line fault protection method. The method comprises steps: travelling wave signals at each measurement point are monitored in real time, if a protected set threshold is reached, a corresponding DC circuit breaker is tripped, all circuit breakers are finally tripped to realize separation of three DC subsystems, and the control mode of each subsystem converter station is switched. According to the travelling waves acquired at the measurement point, whether the fault is subsystem internal fault or subsystem external fault is judged by each subsystem through a fault positioning logic. If the subsystem external fault is judged according to the fault positioning logic, the line of the fault is determined according to the fault positioning logic, or otherwise, the subsystem internal fault is judged. According to an instruction of a dispatching system, the control mode of each converter station and a power control instruction are changed. The technical scheme of the invention can effectively shorten time needed for fault positioning, and power transfer brought by large-range DC power grid locking and influences on the stability of an AC and DC system can be reduced as much as possible. The phenomenon that the disclosed method is not applicable along with complexity of the DC power grid structure does not happen.
Owner:GLOBAL ENERGY INTERCONNECTION RES INST CO LTD +2
Building intelligent lighting system
InactiveCN104902633ALow maintenanceImprove viewing and practicalityElectric light circuit arrangementEnergy saving control techniquesWork statusElectricity
The invention relates to field of intelligent control, and specifically relates to a building intelligent lighting system comprising intelligent lamps, a wireless remote controller, a wireless gateway, a monitor, a server, and terminal devices. The wireless gateway is used to build a wireless lighting network and store electricity information of the intelligent lamps in the server. The server makes analysis of signals output by light sensors and on-off states of lamps in the intelligent lamps and other electricity information of the intelligent lamps to obtain an optimized electricity utilization scheme, and transmits a control command to the intelligent lamps through the monitor and the wireless gateway. Users can control the state of the intelligent lamps both through the wireless remote controller and the terminal devices, and can query the working state of the intelligent lamps by accessing a WEB page of the server through the terminal devices. Through intelligent control, the brightness, color, on-off and other information of the intelligent lamps can be adjusted, a green and energy-saving effect is achieved, and the ornamental value is improved. Moreover, the wireless network adopts a mixed structure, and is highly reliable.
Owner:SHANGHAI UNIVERSITY OF ELECTRIC POWER
Active clamping circuit driven by IGBT
InactiveCN104052048AReduce power lossIncrease gate-collector capacitanceEmergency protective arrangements for limiting excess voltage/currentCapacitanceActive clamp
The invention discloses an active clamping circuit driven by an IGBT. The active clamping circuit comprises a first transient voltage restraint diode, a second transient voltage restraint diode, a diode and a current-limiting resistor, the first transient voltage restraint diode, the second transient voltage restraint diode, the diode and the current-limiting resistor are sequentially connected between a collector and a grid of the IGBT, and a capacitor and a discharging resistor are connected to the second transient voltage restraint diode in parallel. Protection on a dynamic active clamp and a fixed active clamp of the IGBT is achieved. The active clamping circuit is simple in structure and high in universality, parameter setting of active clamping voltage can be carried out according to various application occasions, and the active clamping circuit can be applied to design of IGBT driving circuits under various working conditions.
Owner:BEIJING CED RAILWAY ELECTRIC TECH
Motor control apparatus
InactiveCN103973186AImproved torque reductionRestraint torsionElectronic commutation motor controlElectric motor controlDiscriminatorMotor drive
The invention provides a motor control apparatus. A power running / regeneration discriminator (175) uses a torque current command IqCB and a motor rotating speed [omega]m to identify a power running / regeneration status. A limiter (190) enables the torque current command IqCB to pass when a motor (180) is in a power running status, and in a regeneration status, limits the magnitude of the torque current command IqCB according to a limit value IqLIM and enables the torque current command IqCB to pass. A field current command arithmetic unit (135) uses the motor rotating speed [omega]m to identify a rotation status of the motor (180) and calculates a field current command IdC corresponding to the rotation status. A motor drive part (q-axis current controller (130), d-axis current controller (145), a coordinate converter (160), a PWM controller (165) and a power converter (170)) uses the torque current command IqC passed from the limiter and the calculated field current command IdC to drive the motor (180).
Owner:SANYO DENKI CO LTD
Power factor correction circuit and driving method thereof
ActiveUS8513926B2Avoid Overvoltage ProblemsMinimize impactAc-dc conversion without reversalConversion with intermediate conversion to dcEngineeringControl switch
The present invention relates to a power factor correction circuit and a driving method thereof. The power factor correction circuit receives an input voltage and maintains an output voltage at a constant level by controlling switching operation of a power switch connected to an inductor that supplies the output voltage. In this case, the power factor correction circuit controls switching operation of the power switch by differentiating a control structure for an output voltage respectively according to a stabilization period during which the output voltage is constantly maintained and a start-up period during which the output voltage is increased before being stabilized. In addition, the power factor correction circuit controls the switching operation of the power switch according to the control structure of the start-up period during a predetermined correction delay period from a time that the stabilization period starts.
Owner:SEMICON COMPONENTS IND LLC
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