373results about "Starter arrangements" patented technology

The invention relates to the field of permanent magnet synchronous motor control, in particular to an RANF adaptive harmonic suppression method based on dustpan line optimization, which comprises the following steps: S1, establishing a d-q axis control model for a permanent magnet synchronous motor, listing voltage, current and electromagnetic torque equations, giving a harmonic current equation, and adopting an ANF adaptive notch extraction algorithm to obtain a harmonic current control model for the permanent magnet synchronous motor; obtaining estimated values of specific-order harmonic amplitude and phase, and generating harmonic compensation quantity from the estimated values by adopting a PI regulator so as to realize a steady-state indifference-free harmonic suppression effect; and S2, in order to solve the problem that the ANF adaptive harmonic suppression algorithm is difficult to follow the d-q axis current rapidly changing along with the direct current amount, an RANF adaptive harmonic suppression algorithm adopting an R regulator is proposed, the ANF following performance is greatly accelerated, and the practicability of the ANF is improved. When the motor load or the rotating speed changes, quick response can be achieved, system instability is avoided, the dynamic stability of the system is remarkably improved, and the application scene of ANF adaptive harmonic suppression in the permanent magnet synchronous motor is widened.

A power tool includes an electric motor; a power supply management device; a driving device driving the electric motor to operate to implement a main function; and an operating device being operated to activate one or more functions and output a function signal. The power tool has the main function and an auxiliary function, and the function signal includes a main function signal and an auxiliary function signal. The power supply management device is configured to output a first enable signal when receiving any function signal and output a third enable signal to the driving device when receiving the main function signal. The power tool further includes a first controller configured to output a first drive signal to the driving device when receiving the first enable signal. The driving device drives the electric motor to operate when receiving the third enable signal and the first drive signal.

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 provides a permanent magnet synchronous motor frequency conversion soft start and grid connection device and a control method. The device comprises a power supply grid (1), a permanent magnet synchronous motor (2), three-phase contactors (3), (4) and (5), a variable frequency controller composed of a rectifier (6), an inverter (7) and a control panel (8), a voltage sampling module (9), a current sampling module (10) and a filter inductor (11) at the output end of the inverter. One end of the three-phase contactor (3) is connected with a three-phase inlet wire of the power supply grid (1), and the other end of the three-phase contactor (3) is connected with the input end of the rectifier (6); one end of the three-phase contactor (4) is connected with the output end of the inverter (7), and the other end of the three-phase contactor (4) is connected with the input end of the motor (2); and one end of the three-phase contactor (5) is connected with a three-phase inlet wire of the power supply grid (1). VF open-loop pre-synchronization control is introduced in advance in vector control, power grid synchronization conditions are simulated, a motor is enabled to actively match power grid magnetic field parameters before grid connection, smooth transition of a control mode is realized, and large impact current and electromechanical oscillation are avoided.

An electrically powered aircraft is configured to check the health of its motors by determining a flux linkage associated with each of the motors. The flux linkage may be determined by measuring the back-EMF of stator coils of the motor. The flux linkage may be measured while the motor is not powered or may be estimated when the motor is in use. The flux linkage of a motor may be compared to a corresponding threshold value to assess whether the magnet(s) of the motor have degraded to a point at which they pose safety concerns. The flux linkage values may also be used to project when the motor needs to be maintained and / or replaced. The flux linkage value of a motor may be displayed, along with historical flux linkage values for that motor, to show a magnitude of demagnetization of the magnet(s) of the motor.

A power tool includes a housing, a motor, and an actuator configured to be actuated by a user to cause the motor to operate. The power tool includes a depth sensor located adjacent to the output drive device and configured to generate a distance signal. The power tool includes an electronic controller coupled to the actuator and to the depth sensor. The electronic controller determines a first distance between the depth sensor and the workpiece by monitoring the distance signal from the depth sensor during operation of the motor. The electronic controller determines that the first distance has decreased to be less than or equal to the predetermined threshold distance. The electronic controller changes how the motor is controlled to operate in response to determining that the first distance has decreased to be less than or equal to the predetermined threshold distance.

A method for detecting movement of a vehicle body component moveable by an electric motor having a rotor and a three-phase stator, and a motor vehicle. The method includes: loading two stator phases with a pulse-width-modulated voltage and maintaining a third stator phase at a free-floating state; monitoring the third stator phase as a measuring point for an inductive voltage divider formed using the two stator phases; and detecting movement of the vehicle body component when an electric signal at a measuring point or a variable derived from the electric signal exceeds a specified threshold value. The motor vehicle includes a control device that is operable to perform the method.

The invention belongs to the technical field of motor control, and discloses a control method for switching an open loop to a closed loop of a permanent magnet synchronous motor, which is used for switching the permanent magnet synchronous motor from speed loop open-loop operation to rotating speed current double-closed-loop operation. Calculating an included angle delta between the shafting of the virtual synchronous rotating coordinate system dvirqvir and the shafting of the real rotor synchronous coordinate system dq; and then instantaneous switching of a command value of a current regulator, instantaneous switching of a current space voltage vector, switching of an angle variable used by coordinate transformation, initialization of a previous value of a low-pass filter, initialization of an integral term of the current regulator and initialization of an integral term of a speed regulator are executed in sequence, and open-loop switching and closed-loop switching of the permanent magnet synchronous motor are completed. According to the invention, the switching time is effectively shortened, and the switching stability and universality are improved.

The motor control device includes: a control signal generation unit 512, generating a motor control signal for supplying drive power to a drive motor 60; an advance angle value setting unit 514, setting a control advance angle value θa for advancing a phase of the motor control signal; and an operation state detection unit 513, detecting an operation state of the opening and closing body. The advance angle value setting unit 514 sets the control advance angle value θa in accordance with the operation state of the opening and closing body detected by the operation state detection unit 513.

The invention discloses an electric tool and a control method thereof. The electric tool includes: a functional member; the motor assembly comprises a first motor and a second motor, and at least one of the first motor and the second motor drives the functional part to work; the power supply device is connected with the motor assembly and at least supplies power to the motor assembly; a transmission relation exists between the first motor and the second motor, and when the first motor rotates, the second motor is driven to rotate. The electric tool further comprises a controller connected with the motor assembly, and the controller is configured to control the second motor to start based on the back electromotive force of the second motor after the first motor is started; the scheme can effectively improve the starting success rate of the motor of the electric tool and guarantee smooth work of the tool.

The invention discloses a position-sensorless heavy-load starting method for a permanent magnet synchronous motor. The method comprises the following steps: establishing a discrete current model of the permanent magnet synchronous motor in a two-phase static coordinate system under the excitation of a high-frequency square wave signal; injecting the six-pulse voltage into the permanent magnet synchronous motor based on a three-phase static coordinate system to carry out rotor magnetic pole identification so as to correct the initial electrical angle of the rotor, and further obtaining a rotor position error signal in combination with a discrete current model; a rotor position error signal is processed through an improved phase-locked loop control system based on model reference self-adaption, and then the finally estimated rotating speed and electrical angle of the rotor are obtained; and then inputting the signal as a feedback signal into a magnetic field orientation control system to realize position-sensorless closed-loop starting control of the permanent magnet synchronous motor under a heavy load condition. By means of the method, the reliability of the starting process and the stability of a control system can be remarkably improved, and therefore reliable position-free closed-loop control under the low-speed large-load working condition and even within the full-speed domain range is achieved.

A BLDC motor system having a power stage, a hall sensor and a logical control circuit is discussed. The BLDC motor system improves performances by judging an initial rotation direction through the back electromotive force generated by the stator together with the induced signal sensed by the hall sensor.

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.

A control method, control apparatus and control system for an electric motor, and a computer-readable storage medium are provided. The control method for an electric motor includes: acquiring an initial rotation speed and an initial rotation direction of an electric motor; determining a target start mode for the electric motor according to the initial rotation speed and the initial rotation direction; and according to the target start mode, controlling the electric motor to start. A target start mode, which most conforms to an initial rotation speed and an initial rotation speed direction of an electric motor, can be determined from a plurality of preset start modes, so as to control the electric motor to start.

A motor starting control method, device, and system, the method including: accumulating electrical parameter to obtain accumulated electrical parameter values, which are alternately assigned to a direct-axis electrical parameter and quadrature-axis electrical parameter; accumulating an angular increment to obtain accumulated values of a forced-driving angle; generating a control signal for a motor based on real-time values of the direct-axis electric parameter, quadrature-axis electrical parameter, and forced-driving angle; the control signal drives the motor; repeating said steps until the direct-axis electrical parameter or the quadrature-axis electrical parameter reaches a target electrical parameter, and then continuing accumulating to obtain the accumulated values of the forced-driving angle while forcibly driving the motor based on the corresponding control signal; when the real-time value of the forced-driving angle stays in sync with the rotor angle, the motor completes the startup; the motor is driven by alternately applying two perpendicular forces to the rotor.

The application provides a direct-current motor, a starting control method and device thereof, an air conditioner and a storage medium. The method comprises the following steps: detecting that the controller of the direct-current motor is powered on, obtaining an initial duty cycle corresponding to the direct-current motor pre-stored in the controller; when the initial duty cycle is zero, self-learning the initial duty cycle to obtain a target duty cycle; and controlling the starting of the direct-current motor according to the target duty cycle. The application obtains the target duty cycle, i.e. the optimal starting voltage of the direct-current motor, by self-learning the initial duty cycle when the initial duty cycle is zero, and controls the starting of the direct-current motor according to the target duty cycle when the starting instruction of the direct-current motor is received, so as to avoid the problems of excessive starting voltage or too small starting voltage, excessive starting vibration of the direct-current motor, speed overshoot and delay in starting of the motor, and the problem of poor control of the motor and the controller caused by replacement of the motor or the controller, thereby improving the stability and reliability of the direct-current motor during starting.

To provide a technique capable of holding energization in an electric motor with a simple configuration even after a manual switch for a reciprocating tool is turned off.SOLUTION: A reciprocating tool includes a reciprocating member, an electric motor, a transmission device, a drive circuit, a first manual switch, a switch element and a control circuit. A first contact point of the first manual switch is connected to a power supply, and a second contact point of the first manual switch is connected to the drive circuit. The first manual switch in its on state connects the first contact point to the second contact point. The switch element (i) is turned on when it receives an electric signal, and (ii) establishes electrical continuity between the first contact point and the second contact point in its on state. In response to at least the first manual switch being turned on, the control circuit continues to output the electric signal to the switch element until the drive of the electric motor is stopped.SELECTED DRAWING: Figure 6

The present invention relates to a method for starting a BLDC motor (10) with a trapezoidal shaped induction voltage under high load conditions using a modified two-level discrete fixed-time or fixed-frequency hysteresis current controller, the BLDC motor (10) being driven by an inverter bridge (30) with only one current sensor (20) placed on the busbar and controlled by a processing unit associated with an analog-to-digital converter, the novelty of which consists essentially in the fact that the intensity of the current (Im) of the BLDC motor is controlled by a two-level discrete fixed-time or fixed-frequency hysteresis current controller.

The embodiment of the invention discloses a control method and a control system of a permanent magnet motor, the permanent magnet motor is controlled to start by applying voltage to the permanent magnet motor in at least two stages, and at least one voltage amplitude in the later stage is higher than the voltage amplitude in the previous stage, that is, in the process of controlling the starting of the permanent magnet motor, the voltage amplitude is lower than the voltage amplitude in the previous stage. The amplitude of the voltage applied to the motor is controlled to be gradually increased by stages, so that the impact current can be reduced, smooth starting is realized, and the service lives of the permanent magnet motor and the traction inverter are prolonged. Under at least partial working conditions of locked-rotor, the switching frequency of a power device in a traction inverter connected with the permanent magnet motor is reduced, the conduction time and thermal stress of the power device are reduced, and effective locked-rotor protection is further provided. According to the technical scheme, the starting smoothness and locked-rotor protection of the permanent magnet motor can be considered at the same time, and the system reliability is improved.

A method for detecting an initial position of an electric motor includes determining a delta voltage for each of three pairs of stator windings by sequentially energizing and de-energizing each pair. The delta voltage is measured via an unenergized stator winding connected to the center tap of each corresponding pair. A minimum delta voltage is determined based on the absolute value of the minimum of the three delta voltages. The minimum delta voltage is associated with a remaining stator winding not included in the corresponding pair. Two delta voltages not associated with the minimum delta voltage are compared to determine the proximity of the remaining stator winding to one of the D-axis and the Q-axis of the rotor of the electric motor.

The invention discloses a high-power compressor driving circuit, a high-power compressor and a control method of the high-power compressor. The high-power compressor driving circuit comprises a controller, a three-phase half-bridge driving circuit, a three-phase half-bridge circuit and a direct current-direct current converter, the three-phase half-bridge driving circuit is connected with the controller; the three-phase half-bridge drive circuit is connected with the three-phase half-bridge circuit; the DC-DC converter is connected with the controller and the three-phase half-bridge drive circuit. Wherein the three-phase half-bridge circuit comprises 12 insulated gate bipolar transistors, each phase of the three phases of the three-phase half-bridge circuit comprises 4 insulated gate bipolar transistors, and the three-phase half-bridge circuit is used for driving the permanent magnet synchronous scroll compressor connected with the three-phase half-bridge circuit. The permanent magnet synchronous scroll compressor connected with the three-phase half-bridge circuit is driven in a double-tube parallel current expansion mode corresponding to the three-phase half-bridge circuit, the full-load load power of the permanent magnet synchronous scroll compressor can meet the driving refrigeration requirement of large equipment, the on-load overcurrent capacity is enhanced in the double-tube parallel current expansion mode, and the influence of the environment temperature is reduced.

A fan control system according to the present disclosure includes a control unit that selects a control mode from among a plurality of control modes including a first mode and a second mode. The first mode is a control mode in which an electric signal is supplied to a fan motor to cause the fan motor to operate at a first rotational speed. The second mode is a control mode in which an electric signal is supplied to the fan motor to cause the fan motor to operate at a second rotational speed that is lower than the first rotational speed. The control unit has a function of selecting the second mode during a period after the fan motor is started and before the first mode is selected.

A boost circuit and method is described for supplying a boost voltage to a rotor of the electric machine, just as the electric machine is pulsed on, the boost voltage aids the rotor in quickly overcoming its start-up inductance, rapidly turn on the rotor. As a result, much faster transition times are realized each time the electric machine transitions from the off state to the on state at the start of a pulse. By reducing the transition time, the overall efficiency of the electric machine is significantly improved.

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.

A method and apparatus for detecting the position of a rotor of an electric motor, and an electric tool. The method for detecting the position of a rotor of an electric motor comprises: applying a voltage pulse to each set of windings of an electric motor (S110); acquiring a response current generated by each set of windings on the basis of the voltage pulse, wherein the response current comprises at least one of a bus current and a phase current (S120); on the basis of the response current of each set of windings, determining a required time for each set of windings to reach a preset current threshold (S130); and on the basis of the required time of each set of windings, determining an initial position of a rotor (S140).

The invention discloses a counter electromotive force detection downwind starting method based on a novel arc tangent function, and relates to the technical field of motor control, and the method comprises the steps: collecting the three-phase counter electromotive force of a motor, judging whether the motor is static or not based on the current maximum counter electromotive force, if not, entering downwind starting, and executing the next step; obtaining sector change parameters of a motor rotor based on the three-phase counter electromotive force of the motor, and obtaining the rotation direction and the rotation speed of the motor; clark conversion is carried out on the collected three-phase counter electromotive force of the motor, and the counter electromotive force alpha of the alpha axis and the counter electromotive force beta of the beta axis are obtained; calculating a current motor angle through an arc tangent formula; and calculating motor operation parameters based on the rotating speed and the angle required by the motor for assignment. According to the method, the current angle of the motor can be directly obtained by using the arc tangent formula after the sampled terminal voltage is directly subjected to the clark conversion, back electromotive force reconstruction does not need to be carried out, and the code execution time and logic are greatly optimized.

The application belongs to the field of integrated permanent magnet synchronous motor control system design, and particularly relates to an integrated permanent magnet synchronous motor open loop-closed loop switching control method and a control system. The open loop control is designed at the same time as starting the closed loop calculation. When the open loop output speed reaches the open loop-closed loop switching speed and the closed loop control output target speed reaches the open loop-closed loop switching speed, the open loop control is switched to the closed loop control, and the motor is controlled in the closed loop mode, so that the motor control speed fluctuation is small, the speed following property is good, and the switching process is smooth.

The invention discloses a permanent magnet synchronous motor starting control method based on high-frequency square wave injection. A bus voltage threshold value is set; during initial starting, high-frequency square waves are injected into the d axis, and the rotor position and the angular speed are obtained; performing reverse braking and forward starting control on the rotor according to the rotor position and the angular speed; during braking, reverse torque is applied to the rotor through rotating speed and current double-closed-loop control; circularly acquiring real-time bus voltage and comparing the real-time bus voltage with the bus voltage threshold value; and if the real-time bus voltage exceeds the bus voltage threshold, increasing the voltage amplitude of the high-frequency square wave injected by the d axis. The rotor position and the angular speed are obtained by injecting the high-frequency square waves, and the problem that the rotor observer is large in error at the low speed is solved; when the reverse rotation is started, the current of the stator coil is increased by increasing the voltage amplitude of the high-frequency square wave, so that the stator coil is used as an energy-consuming circuit to consume the counter electromotive force, the real-time bus voltage is reduced, and the cost is reduced.