154results about "Polyphase induction motor starter" patented technology

A system for providing inrush current limiting for induction motor starting. The system utilizes a pre-start controller to initialize operation of a controller including multiple switches for controlling the voltage delivered to a motor having multiple phases. The pre-start controller activates each switch and determines whether a phase current flowing through the switches satisfies a threshold current. The switches are deactivated a phase current satisfies the threshold current. The pre-start controller determines an activation order for each phase and orders phases having higher phase currents higher in the order than lower phase currents, and determines an activation timing. Based on whether the highest phase current is positive or negative, the pre-start controller then activates, using a voltage at a corresponding angle and based on the activation order and activation timing, the phases to de-saturate the flux generated by the phase currents, thereby limiting an inrush current provided to the motor.

The embodiment of the invention discloses a multiplex type three-stage starting power generation controller, and relates to the technical field of aviation three-stage starting power generators. In the starting stage, an H-bridge inverter in the starting power generation controller provides single-phase alternating-current exciting current for a main exciter stator exciting winding through SPWM modulation so as to establish a pulsating magnetic field to provide exciting current for a main motor, and a three-phase full-bridge inverter provides armature current for a main motor stator armature winding through SVPWM modulation. In a power generation stage, an anti-parallel diode of the three-phase full-bridge inverter is used as a rectification circuit of the auxiliary exciter, and the H-bridge inverter adopts a PWM chopping mode to operate as an asymmetric half-bridge circuit. A power generation controller and a starting controller are integrated into a whole, and by changing the modulation mode of a hardware circuit, the control function of the three-stage starting generator at different stages can be realized by only one controller, so that the structure of the starting power generation controller is simplified, the system integration degree of the three-stage starting generator is improved, and the volume and the weight of the system are reduced.

The invention relates to a starting and power generation integrated control method based on externally distributed bosses of a permanent magnet motor, and the method comprises the following steps: determining the initial position of a rotor of the permanent magnet motor relative to a stator through a pulse voltage injection method, and applying a drive signal to a stator coil, so that the motor reaches the rotating speed at which an ignition trigger can stably detect the signal; an ignition trigger is used for obtaining boss signals and conducting shaping processing, and the specific position of the rotor relative to the stator is determined; the stator coil is electrified by utilizing the relative position of the rotor and the stator, the motor is driven to rotate, and flux-weakening voltage regulation control is carried out; and when the power-assisted condition is met, a stator coil corresponding to the permanent magnet motor is electrified by utilizing the relative position of the rotor and the stator, so that switching control from power generation voltage regulation to power-assisted driving of the motor is realized, and power-assisted driving operation is executed. According to the control method, the boss on the rotor is used for starting and power generation voltage regulation control of the permanent magnet motor, and the method is simple and easy to implement.

An alternating current (AC) motor system includes an AC motor with a rotor and a stator with multi-phase AC stator windings. The system also includes a power inverter that generates a multi-phase AC voltage, an AC bus that connects the power inverter to the stator windings, an AC choke that surrounds the AC bus, and a current sensor with a coil wound on or surrounded by the AC choke. The current sensor measures common mode current in the AC bus, and is used in pulse width modulation or slew rate control of the power inverter, ensuring smooth operation and reducing the risk of damage due to common mode current.

The invention relates to a double-fed asynchronous motor debugging method and system based on a back-to-back converter, and belongs to the technical field of motor control. Comprising the following steps: supplying power to a three-phase alternating-current voltage regulator, and charging a direct-current bus capacitor by connecting a grid-side alternating-current contactor with a buffer resistor in parallel; when the DC bus capacitor is charged to a preset amplitude, the digital signal processor sends a closing signal to the AC contactor; after the alternating current contactor is switched on, pure open-loop debugging, current closed-loop debugging and rotating speed closed-loop debugging are respectively carried out on the rotor side; the upper computer controls the pulse width modulator to work, carries out excitation on the rotor, and monitors the voltage and phase of the stator end; when the voltage rises to a preset value and the phase is synchronized with the power grid, a closing signal is sent to the AC contactor at the stator side, and the motor stator is connected to the power grid. The problems that a traditional doubly-fed asynchronous motor is too large in starting current and complex in control link decoupling are solved, and the debugging reliability and efficiency are improved. In addition, debugging does not depend on additional prime mover dragging.

A power converter is configured to measure an output current and to determine a multiphase voltage reference as a function of the output current. Within the same switching period the voltage reference is determined, a modulation routine determines a modulation index for each phase of the output voltage. In some instances, one or more phases must start modulation during the switching period before the new modulation index is determined. The modulation routine stores the value of the modulation index generated from the prior switching period and uses the stored value when a new value is not yet ready. An offset value for the phase voltage which used a modulation index from the prior switching period is determined in order to compensate the phase voltages of the other phases and to maintain a desired line-to-line voltage output from the power converter.

The present disclosure relates to an apparatus comprising a controller, an inverter, a load and a DC link. The DC link is coupled to the load and couplable to a power source. The load comprises an AC electrical component. The inverter is configured to provide an output voltage and an output current to the AC electrical component, the output voltage having an output frequency. The controller is configured to: evaluate a component startup criterion relating to whether the AC electrical component is performing a startup process; in response to a determination that the component startup criterion has been met, operate the inverter in a protected startup mode; and when operating the inverter in the protected startup mode, control the output frequency such that the output frequency increases with time until the output frequency reaches a predefined operating frequency.

The application discloses a variable-frequency-power-frequency automatic switching energy-saving system and method, and belongs to the technical field of motor control, which comprises the following steps: in the variable-frequency starting stage, a motor is driven to run at variable speed by a frequency converter; when the motor reaches full frequency, high power and stable operation, a control device controls the output voltage of the frequency converter to be synchronous with the grid voltage, and the switching to the power-frequency grid is completed when the phases are consistent; when the load decreases and needs to be reduced, the control device starts the frequency converter to make the output voltage of the frequency converter synchronous with the counter electromotive force of the motor in the power-frequency operation, then performs a back switching operation, the motor in rotation is smoothly connected by the frequency converter, and speed reduction control is implemented, and finally the variable-frequency speed regulation operation state is returned; the application realizes automatic selection of the optimal operation mode according to the actual load, avoids energy loss of the frequency converter in the high-speed area, and ensures that the impact on the motor and the grid in the switching process is minimum.

A drive system (10) for an induction motor (200) is provided. The drive system (10) includes a drive unit (12) coupled to the induction motor (200), and a control unit (11). The control unit (11) is configured to control the drive unit (12) to provide a first magnetizing current to the induction motor (200) in response to a trigger signal such that the drive unit (12) is operated for magnetization of the induction motor (200) during a first time period. The control unit (11) is further configured to control the drive unit (12) to provide a torque current to the induction motor (200) such that the drive unit (12) is operated for acceleration of the induction motor (200) during a second time period after the first time period.

The invention relates to the technical field of motor control, and discloses an anti-locked-rotor starting control system. The system comprises a main control module, a dynamic rule base generation module, a phase compensation module, a pre-triggering module and a feedback correction module. The main control module monitors a three-phase current waveform and a rotor position signal of the motor and generates an instantaneous locked-rotor feature vector; the dynamic rule base generation module extracts a current waveform distortion mode of a historical locked-rotor event, and combines a rotor inertia parameter to construct a fuzzy rule set so as to initialize a dynamic rule base; the phase compensation module dynamically compensates the phase current waveform and constructs a stability evaluation function; the pre-triggering module triggers pre-access of the standby power supply according to the phase offset and verifies compatibility; and the feedback correction module generates a feedback parameter according to the locked-rotor risk index and the power supply verification result, and corrects the mapping relationship between the feature vector and the rule base. The system can accurately identify locked-rotor characteristics, dynamically adapt to operation parameters, actively prevent and control locked-rotor risks, and improve the starting stability of the motor.

One aspect of the present disclosure provides an electric power tool including a motor, a drive circuit, a voltage detector, a first calculator, and a second calculator. The drive circuit applies a power-supply voltage to the motor in accordance with a first duty ratio. The voltage detector detects a magnitude of the power-supply voltage. The first calculator calculates a desired duty ratio based on the magnitude of the power-supply voltage detected. The second calculator increases the first duty ratio from an initial value to the desired duty ratio in accordance with a lapse of time. The second calculator varies a rate of increase of the first duty ratio based on the magnitude of the power-supply voltage detected.

This invention discloses a forward / reverse control module based on zero-crossing detection control, comprising a power supply circuit, an interlock delay circuit, a drive circuit, a switching circuit, a detection circuit, and a control unit. The drive circuit is connected in series between the interlock delay circuit and the switching circuit, and the switching circuit is connected in series between the load power supply and the winding terminals of the motor. The signal input terminal of the detection circuit is connected to the switching circuit. The control unit is connected to the interlock delay circuit to detect the presence of a forward rotation signal and / or a reverse rotation signal. The control unit is connected to the drive circuit through the detection circuit, and outputs a braking signal to the drive circuit. The drive circuit drives the corresponding switch in the switching circuit to conduct according to the braking signal, thereby realizing forward / reverse control and braking control of the motor. This invention combines forward / reverse control and braking functions without the need for additional braking components. It allows for adjustment of braking time and force, and features a simple braking structure, excellent performance, and high reliability.

This application provides a motor controller, a powertrain, and an electric vehicle, to resolve a problem of current impact on a power transistor that exists during startup of the motor controller and therefore improve powertrain efficiency and vehicle endurance. The motor controller provided in this application includes a control apparatus and an inverter circuit. The control apparatus is configured to receive a first torque signal, at least one second torque signal, and a third torque signal in sequence. In response to the third torque signal, the control apparatus outputs a startup signal and a third control signal in sequence. The startup signal is used to control the inverter circuit to generate a startup voltage, to avoid current impact that exists when the power transistor is turned on. The inverter circuit receives the third control signal and controls an induction motor to output a torque based on a torque value indicated by the third torque signal . According to the motor controller, the powertrain, and the electric vehicle provided in embodiments of this application, a startup speed of the motor controller can be increased, and current impact that exists during startup of the motor controller can be eliminated.

Techniques are described to continuously calculate an inverter DC power of a synchronous machine, e.g., motor or generator, based on the individual phase currents, DC link voltage, and gate signals, which can be compared against the commanded mechanical power based of the estimated rotor speed and commanded torque. A controller can determine whether to shut down the inverter, such as the pulse width modulation (PWM), if the DC power is greater than a threshold value. Such a threshold can be defined to allow an acceptable position and speed estimation error margin.

Embodiments of the present disclosure relate to soft turn-off for motor controllers. A bidirectional switch for an induction motor is described. The bidirectional switch can include a first power semiconductor transistor having a first source, a first drain, and a first gate. The bidirectional switch can also include a second power semiconductor transistor having a second source, a second drain, and a second gate. The bidirectional switch can include the second source connected to the first source. The bidirectional switch can include a soft start device including a control circuit configurable to provide a first control signal to the first power semiconductor transistor and a second control signal to the second power semiconductor transistor.

The embodiment of the invention discloses a motor star-delta switching circuit and a motor. The motor star-delta switching circuit comprises a star-delta starting control circuit, a protection circuit, a star-shaped starting circuit and a delta starting circuit. When the motor is started in a star-delta mode, the operation time of the star-shaped starting circuit can be controlled through circuit setting in the star-delta starting control circuit based on parameters of a second resistor, a sixth resistor and a third capacitor and the voltage corresponding to the reverse end of a comparator. And the interval time for switching the star-shaped starting circuit to the triangular starting circuit is controlled based on the parameters of the fourth resistor and the sixth capacitor and the voltage corresponding to the reverse end of the comparator, so that star-delta mode starting of the motor is realized. In the star-delta starting process, only corresponding hardware circuit parameters need to be adjusted, software end control does not need to be introduced, the problem of software end system bug does not exist, and the motor star-delta switching circuit is high in stability and low in cost.

A solid-state controller for limiting startup current in an induction motor is provided. The solid-state controller includes a first comparator configured to generate a first comparison based on comparing a rotor speed of the induction motor with a rotor speed threshold. The solid-state controller includes a phase current limiter configured to generate a startup current limit based on the comparison received from the first comparator. The solid-state controller includes a second comparator configured to generate a second comparison based on comparing a startup current of the induction motor with the startup current limit. The solid-state controller includes a microprocessor configured to generate a firing phase angle based on the second comparison, where the firing phase angle is a phase angle at which the solid-state controller is turned on, and generate a stopping time at which the solid-state controller is turned off.

Embodiments of the present disclosure relate to a method, apparatus for operating a conduction assembly, a start device, and a computer-readable medium. The conduction assembly is coupled between an AC power supply and an inductive load, and comprises a first switch device and a second switch device which are in anti-series connection, the first switch device comprises a first body diode in anti-parallel connection with the first switch device, and the second switch device comprises a second body diode in anti-parallel connection with the second switch device. The method comprises: conducting the conduction assembly at a first conduction angle in a first cycle; conducting the conduction assembly in a second cycle at a second conduction angle that is greater than the first conduction angle, wherein in the first cycle and second cycle, a turn-off timing of the first switch device or the second switch device in anti-parallel connection with the first body diode or second body diode having a conduction direction the same as a current direction is determined based on the current flowing through the conduction assembly. The method proposed here may reduce the power loss of the soft start circuit.

Disclosed are a method for controlling an induction motor, a device, an equipment and a storage medium. The method includes: determining an optimal starting frequency by acquiring initial equivalent circuit parameters of the induction motor at zero speed, and determining a starting voltage by a preset starting current, so as to enable the induction motor to enter a starting operation phase; then determining that the induction motor switches from the starting operation phase to the steady operation phase when it is determined that the motor starting speed of the induction motor in the starting operation phase is accelerated to be consistent with a preset steady operation speed; and using the optimal frequency with the updated equivalent parameters identified with the operation current and voltage values, and adjusting the drive voltage to maintain the motor speed to the required one.

The invention discloses an electronic power soft starter, and relates to the technical field of power equipment soft start, the electronic power soft starter comprises a silicon controlled rectifier heat dissipation system, a silicon controlled rectifier trigger system and a soft start control system, the silicon controlled rectifier heat dissipation system adopts a double heat dissipation mode of oil immersion and water cooling, and three-phase six silicon controlled rectifier elements are immersed in insulating oil; the bottom of the oil box is placed in the water box; according to the silicon controlled rectifier trigger system, two silicon controlled rectifiers in each phase are connected in anti-parallel and are connected with relay coils through buttons, and contacts of relays are connected with control electrodes of the silicon controlled rectifiers. According to the electronic type electric power soft starter, a contactless spark design is adopted, sparks generated by a traditional mechanical contact type starter are effectively avoided, and the safety production level is improved; and meanwhile, the short-circuit instantaneous breaking protection circuit breaker is adopted, so that the safety protection performance of the equipment is further enhanced. The heat dissipation mode is innovative, oil immersion and water cooling are combined, the heat dissipation cost is reduced, and hot water can be recycled.

The invention relates to a motor driving device and a motor driving method, and the motor driving device comprises an MCU micro-control unit, a frequency conversion control module, an electronic bypass module and a mechanical bypass module. The MCU is used for controlling an inverter in the frequency conversion control module to limit the starting current to be smaller than the target current in the starting stage and controlling the frequency conversion control module to be closed after the rotating speed of the motor to be driven reaches the rated rotating speed. The electronic bypass module is triggered to be fully conducted and the mechanical bypass module is controlled to be short-circuited when the current of the to-be-driven motor crosses the zero point, and the target current is one time of rated current of the to-be-driven motor; and the MCU is also used for closing the electronic bypass module after determining that the mechanical bypass module is short-circuited. According to the invention, the problem that the voltage of a power grid drops suddenly because the starting current reaches 6-8 times of the rated current when the motor is directly started in the prior art is solved.

An integrated electric control cabinet of a spinning blowing and suction fan is used in the field of spinning equipment. Comprising a 380V three-phase power supply, a circuit breaker, a contactor, a main motor M1, a forward and reverse rotation motor M2 and a PLC (Programmable Logic Controller), wherein a start button SA1, a stop button SB1, a derailing prevention proximity switch SA2, a forward rotation proximity switch SA3, a reverse rotation proximity switch SA4, a forward rotation over-limit safety switch SA5, a reverse rotation over-limit safety switch SA6, a left anti-collision photoelectric switch SA7 and a right anti-collision photoelectric switch SA8 are connected in parallel on the PLC. Intelligent operation of the blowing and suction fan can be effectively controlled through the PLC, the defects that an existing spun yarn blowing and suction fan often collides with a doffing machine in the spinning use process, equipment is damaged, the blowing and suction fan derails and the like are overcome, the problem that an existing blowing and suction fan cannot stop changing the operation direction when encountering an obstacle is solved, the circuit is simple, and operation is convenient. Running is reliable, and work is stable.

The utility model discloses a transmission system. The transmission system comprises a motor; one end of the speed regulator is connected with the motor, and the other end is disconnected with the load before the motor is started and connected with the load after the motor is started; the control system is used for controlling the operation states of the motor and the speed regulator; before the motor is started, the control system controls the motor to be powered off and controls the speed regulator to be powered on, so that the speed regulator drives the motor to rotate, and when the motor reaches the rated rotating speed, the control system controls the speed regulator to be powered off and simultaneously controls the motor to be powered on. According to the utility model, the starting impact can be reduced, the influence on the motor and a power grid is reduced, the current demand during starting is reduced, the capacity of a power grid system is reduced, smooth starting can be realized, the motor is driven to rotate through the speed regulator, the motor generates no-load counter electromotive force, and the motor can be started more stably when electrified; the reliability and the stability of motor starting are improved, and the mechanical stress during motor starting is reduced.

A motor-driving apparatus for driving a motor having a plurality of windings respectively corresponding to a plurality of phases is provided. The motor-driving apparatus includes a first inverter having a plurality of first switching devices and connected to first ends of the plurality of windings and a second inverter having a plurality of second switching devices and connected to second ends of the plurality of windings. A third switching device is configured to selectively connect and disconnect points at which a number of turns of each of the windings is divided in a preset ratio. A controller is configured to adjust an on / off state of the first to third switching devices based on required output of the motor.

The utility model discloses a restarting device for maintaining a fault reset starting signal. The restarting device comprises a frequency converter VVVF, a logic control module, a timing module and an expansion relay, the frequency converter VVVF comprises a control button, a reset terminal and a starting terminal; the expansion relay is electrically connected with the frequency converter VVVF; the reset terminal is used for controlling the frequency converter VVVF to reset; the timing module is electrically connected with the logic control module and is used for presetting a time threshold value; the logic control module comprises a first contact and a second contact which are used for inputting a working power supply, the first contact is connected with a live wire L of a control power supply, and the second contact is connected with a null line and is used for detecting the voltage change of the power supply. Compared with the prior art, the restarting device provided by the utility model has the advantages that the operation signal of the frequency converter can be ensured to be in an on-line logic keeping mode, the efficiency is high when the frequency converter is judged and restarted, and the continuous production of factories and enterprises is further ensured.

The invention discloses a star contactor module, a star-delta contactor module and a star-delta starting switch, and the star contactor module comprises a star module housing, a first electromagnetic system, a first contact support, and a first contact assembly. The first contact assembly comprises three first moving contacts and three groups of first static conductive structures, and the three first moving contacts are in short circuit through short circuit pieces; each first static conductive structure comprises a first wiring section, a contact section and a second wiring section, and the first wiring section, the contact section and the second wiring section in the same first static conductive structure are always kept in a connected state on a circuit; the first electromagnetic system comprises a first armature which is arranged in a sliding mode, the first contact support and the first armature are arranged in a synchronous movement mode, the three contact sections are located below the three first moving contacts respectively, and connection and disconnection of a first contact assembly are achieved through sliding of the first contact support; the star contactor has the characteristic of independent modularization of the star contactor module.

Motor drive device (1) comprising: a drive unit (2) configured to drive a starter / generator (4) which is directly connected to a motor via a rotating shaft by performing on / off control of each of the switching elements (UH, UL, VH, VL, WH, WL) in a bridge circuit (23) to drive a motor; and a drive control (3) designed to control a drive operation performed by the drive unit (2) for the starter / generator (4), wherein the drive unit (2) is configured to control a motor drive voltage for the starter / generator (4) by changing the ON time period of the switching elements (UH, UL, VH, VL, WH, WL) of the bridge circuit (23) and to perform an active freewheeling operation to raise a backfeed voltage generated by the starter / generator (4) by alternately switching on the predetermined switching element and a complementary switching element within a period in which a gate drive signal for a predetermined switching element is at a low level, thereby forming a current path caused by a backfeed voltage and wherein the drive control (3) is configured to instruct the drive unit (2) to control the motor drive voltage and the switching on and off of the active freewheel on the basis of a battery voltage.

The utility model relates to the field of automatic control, and particularly discloses a motor soft starting device suitable for pump loads, which comprises a main circuit breaker module, a three-phase antiparallel thyristor module, a current detection module, a bypass contactor module, a thermal overload relay module and a user interface module. The main circuit breaker module is used for controlling start and stop of a motor and generating a control signal according to a preset start parameter; the three-phase antiparallel thyristor module is used for smoothly adjusting voltage applied to a motor stator winding; the bypass contactor module comprises one or more contacts to ensure that current passes through the thyristor assembly in the soft starter; the current detection module monitors the working current of the motor in real time and feeds back the detected current value to the main circuit breaker module; the thermal overload relay module is used for preventing the motor from being damaged due to long-time overload operation; the user interface module is used for setting soft start parameters and displaying the running state of the motor.

A drive system (10) for an induction motor (200), comprising: a drive unit (12) coupled with the induction motor (200); and a control unit (11). The control unit (11) is configured to control the drive unit (12) to provide a first magnetization current to the induction motor (200) in response to a trigger signal such that the drive unit (12) is operated for magnetization of the induction motor (200) during a first time period. The control unit (11) is further configured to control the drive unit (12) to provide a torque current to the induction machine (200) such that the drive unit (12) is operated for acceleration of the induction machine (200) during a second time period following the first time period.