902 results about "Synchronous motor" patented technology

The invention relates to the technical field of natural gas treatment, and particularly discloses a turbine and motor double-drive magnetic levitation natural gas expansion recompression unit, system and method, and the turbine and motor double-drive magnetic levitation natural gas expansion recompression unit comprises a natural gas expansion machine, a high-speed synchronous motor and a natural gas compressor which are coaxially and rigidly connected; the magnetic suspension supporting system comprises an expansion side magnetic suspension bearing arranged at the output end of the natural gas expansion machine and a compression side magnetic suspension bearing arranged at the input end of the compressor, and is used for realizing non-contact suspension and torque transmission of the rotor; the electric control unit comprises an electric appliance cabinet and a pressure sensor, a converter and a main controller are arranged in the electric appliance cabinet, the converter is connected with a power grid and the high-speed synchronous motor, and the main controller dynamically adjusts the operation mode and power of the high-speed synchronous motor by taking the outlet pressure of the natural gas compressor as a control variable. The natural gas compressor is driven by the natural gas expansion machine and the highly synchronous motor, the unit with the reverse power generation function is adopted, the operation flexibility of the unit is improved, and the comprehensive utilization rate of energy is remarkably increased.

The invention discloses a performance simulation method, system and equipment of a synchronous motor and a medium, and relates to the technical field of motor engineering and simulation technologies. According to the method, electromagnetic parameters are obtained based on a geometric structure, material attributes and current parameters of a motor; according to loss data in the electromagnetic parameters, calculating to obtain a temperature distribution data set of each component in the motor; according to the electromagnetic force and temperature distribution data set in the electromagnetic parameters, calculating stress distribution and deformation of each component in the motor; carrying out fusion processing on the electromagnetic parameters, the temperature distribution data set and the stress distribution to obtain a fusion data set; fusing the data set to obtain an initial multi-physics field coupling model; performing parameter correction on the initial multi-physics field coupling model to generate a synchronous motor multi-physics field coupling model; and performing simulation according to the synchronous motor multi-physics field coupling model to obtain performance simulation data. By implementing the technical scheme, a reliable basis can be provided for design optimization, performance analysis and fault diagnosis of the motor.

The invention relates to the technical field of motor control, and discloses an axial magnetic flux hybrid excitation synchronous motor field weakening control system based on multi-source feedback. According to the system, a motor digital twinborn model is constructed, and real-time operation data are collected by using a multi-source sensor and synchronized to the model; establishing a three-dimensional electromagnetic field state space based on the model, extracting features through a manifold neural operator, and generating a multi-dimensional excitation state feature set; determining an excitation anomaly feature index set according to the feature set distribution density; collecting data in real time, extracting current excitation characteristic parameters, mapping the current excitation characteristic parameters to a three-dimensional electromagnetic field state space, calculating spatial correlation with the abnormal index set, and outputting weak magnetic demand correlation factors; and finally, according to the correlation factor, the feature set and real-time data iteration updating operator parameters, a control instruction is generated to dynamically adjust the coupling proportion of the electrical excitation component and the permanent magnet excitation component. According to the system, comprehensive perception and accurate regulation and control of the motor operation state are realized, and the adaptability and reliability of field weakening control are improved.

The present invention belongs to the technical field of parameter identification for permanent-magnet synchronous motors. Disclosed are a parameter identification method and apparatus for a permanent-magnet synchronous motor, and a storage medium and a device. The method comprises: using a variable step-size feedback neural network algorithm to solve a voltage equation and a d-q axis current discrete state equation, which take cross-coupled inductance into consideration, of a permanent-magnet synchronous motor in a dq coordinate system, so as to obtain intermediate parameters generated in the process of constructing the d-q axis current discrete state equation; and performing calculation on the basis of the intermediate parameters, so as to obtain the stator resistance, the d-axis inductance, the q-axis inductance, the cross-coupled inductance and the permanent-magnet flux linkage of the permanent-magnet synchronous motor, and thereby completing parameter identification. The present invention takes cross-coupled inductance into consideration and uses the variable step-size feedback neural network algorithm, such that the computational load is extremely small, the degree of complexity is reduced, rapid and effective identification can be realized, and errors can be reduced; in different convergence time periods, the algorithm adjusts the step size on the basis of the magnitude of steady-state errors, such that identification results approach stable values more quickly, thereby improving the speed and stability of convergence.

The invention relates to the technical field of new energy grid connection, in particular to a new energy grid-connected inverter system based on a double-stator synchronous motor interface, which comprises a three-phase inverter and a double-stator synchronous motor, the double-stator synchronous motor comprises a first stator, a rotor and a second stator. Planar air gaps exist between the rotor and the first stator and between the rotor and the second stator. The rotor comprises a first rotor and a second rotor which are rigidly connected, the first rotor is axially adjacent to the first stator, the second rotor is axially adjacent to the second stator, and a magnetic isolation ring is arranged between the first rotor and the second rotor; each of the first stator and the second stator comprises a stator core and an armature winding, the first rotor comprises a first rotor core, an excitation winding and a starting winding, and the second rotor comprises a second rotor core and a permanent magnet. According to the invention, the double-stator configuration can realize voltage transformation and frequency conversion functions, and can solve the problems of reduced power grid inertia, insufficient short-circuit capacity, aggravated broadband oscillation risk and the like caused by grid connection of large-scale new energy through power electronic equipment.

The invention provides a grid-connected system and method based on parallel operation power equalization of synchronous motor units, and relates to the technical field of new energy and electric power engineering. The system comprises a new energy station power generation system and a parallel synchronous motor unit group, wherein the parallel synchronous motor unit group at least comprises two synchronous motor units which have the same electrical parameters and are connected in parallel; the first end of the parallel synchronous motor unit group is connected with the new energy station power generation system, and the second end is connected with the power grid. The method comprises the following steps: connecting one ends of all synchronous motor units to the same power supply bus, applying excitation current to the motor at the end, applying excitation current to the motor at the other end, then measuring the generator end voltage waveform, adjusting the relative mechanical angles of the synchronous motor units according to the measurement result, and ensuring that the relative mechanical angles of all the motor units are equal. And power equalization between parallel synchronous motor units is realized. The system structure can be simplified, the cost can be reduced, and the reliability and the flexibility of the new energy grid-connected system can be improved.

The invention relates to the technical field of driving control of symmetrical vacuum pressure control valves, in particular to a zero-point-free zero returning method of a double-position synchronous motor for a symmetrical vacuum pressure control valve, which is suitable for scenes needing high-precision pressure control, such as semiconductor manufacturing, vacuum coating, precision vacuum detection and the like. The problems that in the prior art, the vacuum sealing performance is damaged by depending on a special sensor, cost is high, abrasion of a sealing ring is aggravated due to zero point fixation, and double-shaft synchronization precision and load distribution are disjointed are solved. According to the method, the position where the sealing ring reaches the sealing pre-tightening force serves as a dynamic non-fixed zero point, an additional zero point sensor or a collision sensor or a horizontal sensor is not needed, the current-torque coupling characteristic of a motor is utilized, and full-process automatic control is achieved through a high-precision Hall current sensor and an incremental encoder. The method comprises the following specific steps: initializing motor parameters, establishing a T = K * I mapping relation, calibrating a current overload threshold value, calibrating a current detection module, synchronously starting and operating double motor shafts, identifying a collision state based on current detection, locking and verifying a zero returning position, and judging zero point uniqueness based on torque uniformity. The double-shaft zero returning repetition precision is high, zero point uniqueness judgment fits the actual working condition, uneven abrasion of the sealing ring can be reduced, the service life of the sealing ring and the maintenance period of the valve are prolonged, meanwhile, the equipment manufacturing cost and the maintenance difficulty are reduced, and the vacuum sealing stability and the pressure control precision of the symmetric vacuum pressure control valve are effectively improved.

The invention discloses an electromagnetic noise suppression control method for a multi-phase self-excitation synchronous motor. A driving system of the synchronous motor comprises a double-closed-loop control system and an inverter. The specific method comprises the steps that the double-closed-loop control system outputs voltage reference signals of all coordinate axes, and all the coordinate axes are arranged in an electromechanical energy conversion plane and a non-electromechanical energy conversion plane respectively; injecting the square wave signal into a selected coordinate axis, and cooperatively adjusting excitation and noise values by using the positive correlation between excitation current and the amplitude of the square wave and the negative correlation between the excitation current and the frequency of the square wave; and then outputting the adjusted voltage reference signal, processing the adjusted voltage reference signal and other voltage reference signals, and outputting the processed voltage reference signal and other voltage reference signals to an inverter to generate a driving voltage. Therefore, the square wave amplitude is synchronously increased and the excitation current is kept stable when the noise reduction of the square wave frequency is improved by utilizing the quantitative relation that the excitation current is positively correlated with the square wave amplitude and negatively correlated with the square wave frequency, so that the load capacity of the synchronous motor is prevented from being reduced.

The invention belongs to the field of synchronous motor rotor position signal acquisition and processing, and particularly relates to a resolver angle compensation method which can improve the motor rotor position signal detection precision. The method comprises the following steps: step 1, acquiring rotary power transformation angle values of n periods; 2, determining an error array of n periods according to the electrical angle value of each period; step 3, performing interpolation calculation on the error array of n periods to obtain a 2-degree error distribution array; and 4, compensating the real-time sampling rotary power transformation angle according to the 2-degree error distribution array.

A torque ripple reduction method for a synchronous electric motor of a vehicle includes obtaining, by a control system, look-up tables (LUTs) that each include harmonic currents that satisfy a constrained objective function for phase current magnitude for the synchronous electric motor, based on a requested motor torque, determining, by the control system and using the LUTs, a plurality of currents including fundamental direct and quadrature currents and 6th order and 12th order harmonic quadrature currents, determining, by the control system, direct and quadrature voltages for the synchronous electric motor based on the plurality of currents including injection of the 6th and 12th order harmonic quadrature currents, and controlling, by the control system, the synchronous electric motor based on the determined direct and quadrature voltages to at least one of reduce torque ripples and increase efficiency of the synchronous electric motor.

The invention discloses a motor adaptive harmonic suppression system and method fused with LSTM prediction, and belongs to the technical field of power electronic control. Comprising a harmonic feature extraction module, a trapezoidal angle prediction module, an integral adjustment module and a trapezoidal voltage compensation module. The harmonic feature extraction module converts the three-phase current into dq-axis current; the trapezoidal angle prediction module establishes a model for predicting an optimal initial trapezoidal angle based on a long short-term memory neural network according to the d-axis harmonic current, the motor rotating speed and the bus voltage; the integral adjusting module adjusts a trapezoidal angle on line by inputting a harmonic error; and the trapezoidal voltage compensation module is used for modulating trapezoidal compensation voltage and outputting compensation voltage required by an alpha axis and compensation voltage required by a beta axis. According to the invention, prediction of the long-short-term memory neural network and online adjustment of the trapezoidal angle and modulation of the trapezoidal compensation voltage of the integrator are fused, the harmonic current of the permanent synchronous motor control system can be effectively inhibited, the torque ripple of the motor is reduced, and the performance of the motor is improved.

The invention discloses a synchronous motor modular excitation active vibration suppression method for eccentric vibration, and the method comprises the steps: dividing a rotor excitation winding into 2P independent current control excitation modules in the circumferential direction, and respectively arranging an X-direction displacement probe and a Y-direction displacement probe, obtaining a first displacement signal and a second displacement signal of the rotor mass center relative to the stator and a rotor mechanical angular speed; performing band-pass filtering on the first displacement signal and the second displacement signal, and extracting a first displacement first-order component and a second displacement first-order component; calculating the shortest air gap direction angle and the eccentricity amplitude under the stator coordinate system, calculating the eccentricity, and calculating a first-order eccentricity coefficient; calculating a shortest air gap direction angle under a rotor coordinate system, and calculating an equivalent correction coefficient; and according to the equivalent correction coefficient, the first-order eccentricity coefficient, and the shortest air gap direction angle and the mechanical position angle under the rotor coordinate system, the injection amount of each excitation module is calculated, an excitation current instruction is generated and output to the corresponding excitation module, and active suppression of the unbalanced magnetic pulling force is realized.

The invention discloses a hybrid excitation synchronous motor control method and system, and belongs to the technical field of motor control. The problem that a motor control system can operate at high precision when a position sensor breaks down is mainly solved. The method comprises the following steps that when a position sensor breaks down, a system is switched to an active short circuit protection (ASC) mode, and operation of a motor is controlled by giving instruction values of d-axis current and q-axis current in the mode; then, in an ASC mode, estimating a rotor angle through a voltage equation in a static coordinate system, so as to obtain an electrical angle of a rotor; after the rotor angle estimation is completed, the system is switched from the ASC mode to the vector control mode without the position sensor, and the d-axis voltage and the q-axis voltage are adjusted in the mode, so that the motor can be continuously and accurately controlled and stably run. The invention provides an efficient and safe motor control method, and the safety and reliability of the electric vehicle under the condition of sensor fault are effectively improved.

The propulsion hydraulic system for the vertical shaft heading machine comprises a propulsion oil cylinder set, a hydraulic control system, a hydraulic control system and a hydraulic control system, and the propulsion oil cylinder set comprises a plurality of propulsion oil cylinders; the synchronous motor is formed by rigidly and coaxially connecting a plurality of hydraulic motors, and a rod cavity of each thrust cylinder is connected with an oil inlet of each hydraulic motor; the first control valve is connected with the pressure oil pipeline, the first oil return pipeline, rodless cavities of the propelling oil cylinders and oil outlets of the hydraulic motors; the second control valve is connected with the pressure oil pipeline and the rodless cavity of each thrust cylinder; and the flow capacity of the first control valve is greater than that of the second control valve. Functional requirements of high-pressure low-speed propelling and low-pressure fast synchronous stretching of the cutter head can be met, and the system is simple, easy to debug and low in cost.

The invention relates to the technical field of distributed energy grid-connected control, in particular to an intelligent monitoring ball enhanced distributed power supply coordination pre-synchronization control method and system, and the method comprises the steps: deploying a master intelligent monitoring ball at a grid-connected point, deploying slave intelligent monitoring balls at the output ends of all distributed power supplies, and forming a star-shaped sensing network; based on a multi-objective optimization algorithm, calculating a pre-synchronization target parameter and an adjustment weight of each distributed power supply, and generating a coordination control instruction; the virtual synchronous motor module receives the coordination control instruction, dynamically adjusts a virtual inertia and a damping coefficient, and adjusts output voltage, frequency and phase through a pre-synchronization execution unit; and after the synchronization reaches the standard, sequentially closing the grid-connected switches according to a preset power supply response priority sequence to complete the grid-connected action. According to the invention, a technical architecture of global monitoring-coordinated decision-precise execution-closed loop optimization is constructed, so that the stability and precise control problem during high-permeability distributed energy grid connection is solved.

The invention relates to the field of construction tools, in particular to light foam concrete pouring and conveying equipment which structurally comprises a base, a horizontally-arranged discharging device is arranged at the top of the base, an upper cover plate is installed on the upper surface of the discharging device, a feeding pipe is arranged on one side of the upper cover plate, and the discharging device comprises a guide pipe and a buffer. The buffer is connected with a feeding hopper, the feeding hopper and a bottom pipe at the bottom form a groove body, a rotary feeding rod is arranged in the buffer and the bottom pipe, the feeding rod is connected with a driving motor main shaft installed outside the feeding hopper, the synchronous motor drives the middle pipe to rotate, and the synchronous motor is electrically connected with a driving motor main board. The long-distance conveying capacity of foam concrete is achieved, defoaming in the start-stop process is greatly reduced, the effective pushing torque of the feeding rod is concentrated in the axial conveying direction by means of the segmented design of the pre-conveying section and the conveying section of the feeding rod and the radial limiting effect of the buffer, radial overflow of materials is restrained, and damage to foam caused by radial shearing is reduced.

The invention discloses an asymmetric six-phase hybrid excitation synchronous motor, a control algorithm and a two-gear transmission thereof, a stator winding of the motor is composed of two sets of three-phase symmetric windings in star connection, the first set of windings and the second set of windings are respectively connected to two three-phase PWM (Pulse Width Modulation) controllers, namely a main controller and an auxiliary controller, and the main controller and the auxiliary controller are respectively connected with the three-phase PWM controllers. And the two controllers are jointly powered by a vehicle-mounted battery. According to the asymmetric six-phase hybrid excitation synchronous motor, the control algorithm and the two-gear transmission thereof, under the condition that the battery voltage is limited, the output power of the motor can be further improved, in addition, the motor rotor is powered by the excitation winding, the excitation winding of the rotor is directly regulated and controlled in real time, and the efficiency of the motor is improved. And the high speed, miniaturization and high efficiency of the vehicle-mounted synchronous motor are greatly improved.

To provide a rotor structure capable of efficiently cooling a cooling target part inside a synchronous motor.SOLUTION: A rotor structure that supplies oil to a cooling target part inside a synchronous motor in which a rotor 10 rotates synchronizing with a revolving magnetic field generated in a stator is provided. The rotor 10 includes a plurality of permanent magnets 101, 102, 103, and 106, which is one cooling target part, and a cylindrical rotor core 30 in which a plurality of magnet holes 31 for having the permanent magnets 101 and 102 embedded therein are formed. The rotor 10 is configured so that the oil flows in an axial direction inside the rotor core 30, passing through the plurality of magnet holes 31.SELECTED DRAWING: Figure 4

The invention discloses a device and method for improving synchronous tracking precision of a double-permanent-magnet synchronous motor motion platform servo system, and belongs to the technical field of numerical control. Synchronous control of the double permanent magnet synchronous motors is realized by using the preset performance cross coupling controller; estimating system lumped disturbance through a self-adaptive extended state observer, and inhibiting the system lumped disturbance by adopting a novel sliding mode maker; according to the novel sliding mode controller, an exponential function term and a power function term are added in the reaching law to enable the system state to converge rapidly, when the system state is close to a sliding mode surface, the exponential term in the reaching law is attenuated rapidly, the improved power function term plays a leading role, convergence stagnation caused by premature reduction of the reaching rate is avoided, the adaptability of the reaching rate is enhanced, and the control precision is improved. The arrival time is reduced. A sigmoid function is used for replacing a switching function, continuous control input is achieved, and high-frequency buffeting is weakened. And the high-performance Hall sensor and the incremental encoder are adopted, so that the signal acquisition precision is improved.

To improve power efficiency of a synchronous motor in a wide speed range from a low speed to a high speed.SOLUTION: In a pole-number switching method, the current value of AC current supplied to an armature is reduced at low speed by increasing the number of poles and increasing the torque multiplier of the electric motor, thereby reducing copper loss, and loss at high-speed rotation (mainly iron loss) is reduced at high speed by decreasing the number of poles and lowering the voltage and frequency of the AC current supplied to the armature. Furthermore, a further power-efficiency improvement effect is provided by connecting the circuit such that, during driving of the electric motor, inverter power-supply current of an armature winding becomes a power supply for a field winding, and such that, during regenerative braking, current generated from the armature winding is regenerated to a battery efficiently.SELECTED DRAWING: Figure 2

The invention provides an MW-level full-superconducting synchronous motor based on stepped superconducting coils, which relates to the field of motors and comprises a stator superconducting winding, a rotor superconducting winding, a stator low-temperature sealing system, a rotor dynamic low-temperature sealing system and a vacuum sealing system. The stator superconducting winding provides a low-temperature operation environment through the stator low-temperature sealing system, the rotor superconducting winding provides a low-temperature operation environment through the rotor dynamic low-temperature sealing system, and the vacuum sealing system of the motor provides a vacuum environment for the rotor dynamic low-temperature cooling system and the stator low-temperature cooling system at the same time. The design of the stepped stator coil and the rotor coil can effectively utilize the internal space of the superconducting motor, and improves the electromagnetic parameters of the motor at the same time.

The invention discloses an efficient purifying and collecting cover for automobile laser cutting smoke dust, and relates to the technical field of automobile manufacturing, the efficient purifying and collecting cover comprises a workpiece conveying device, a multi-stage adjusting support, a dust collecting cabinet, a laser cutting mechanism and a dust sucking mechanism, the multi-stage adjusting support is based on a bearing base plate, and a servo driving unit drives a lifting screw rod to achieve overall lifting; a rotating motor drives a fine adjustment screw rod to drive a fine adjustment plate to perform accurate adjustment, a bearing plate of the laser cutting mechanism is fixed to the fine adjustment plate, a laser emission head in a sliding guide rail adapts to multi-position cutting through a synchronous motor, an axial screw rod and an auxiliary rolling wheel, and a negative pressure dust collection cavity of the dust collection mechanism is fixed to the bearing plate. Smoke dust is conveyed to the dust collection cabinet through the high-pressure vortex fan and the conveying pipeline, the dust collection cabinet adsorbs the smoke dust through a powerful negative pole magnetic plate, and a dust collection drawer is convenient to clean. And a precise filter screen, a non-woven fabric filter layer and a centrifugal induced draft fan are arranged in the exhaust channel, so that multi-stage purification of smoke dust is realized, exhaust is guaranteed to reach the standard, and an automobile laser cutting working condition is adapted.

The invention relates to an automatic discharging device for a satellite thermal test monitoring material. The automatic discharging device comprises a main body and a case arranged on the main body, the wire winding assembly, the wire combining tensioner and the raw material frame assembly are sequentially arranged on the main body in the raw material conveying direction; a synchronous motor for driving the winding assembly to rotate is arranged in the case; the wire combining tensioner comprises a support and a tension sensor arranged on the support, and the tension sensor is electrically connected with the case; the raw material frame assembly comprises a material shaft and at least two raw material discs used for winding raw material lines, and the raw material discs can rotate on the material shaft. An intelligent anti-overload driver is arranged in the machine box and dynamically sets a current threshold value according to the tensile strength of the raw material line, and closed-loop control is formed by the intelligent anti-overload driver and the tension sensor. According to the invention, blanking of a single lead can be realized, simultaneous doubling blanking of leads of multiple specifications can also be realized, operation is simple, automation and intelligentization are realized, the coil inserting precision is high, and a lead protection function is realized.

The invention relates to the technical field of synchronous motors, in particular to a low-voltage high-power high-efficiency permanent-magnet synchronous motor, which comprises a casing and an end cover fixedly mounted at one end of the casing, and further comprises a rotating shaft, a permanent-magnet motor and a permanent-magnet motor, the through hole is formed in the end cover; the filter plate is detachably mounted in the through hole, and a plurality of filter holes are formed in the filter plate; the multiple transverse plates are installed in the through holes from top to bottom in a linear array mode and located on one side of the filter plate, and intervals exist between the adjacent transverse plates and are the same; the lead screws are rotationally mounted in the through holes and located on one side of the transverse plate, and the number of the lead screws is equal to that of the transverse plate; the moving frame is movably mounted on the outer side of the lead screw, a chute is formed in one side of the moving frame, and the part provided with the chute is slidably attached to the surface of the transverse plate. According to the low-voltage high-power high-efficiency permanent magnet synchronous motor provided by the invention, small-amplitude shaking of the movable plate in the notch can be realized through the shaking assembly, a cleaned mixture is prevented from being adhered to the movable plate, and subsequent cleaning is facilitated.

The invention discloses a network construction type energy storage inverter parallel control method considering SOH (state of health) and SOC (state of charge), and relates to the technical field of energy storage. Comprising the steps that n energy storage inverter modules (module 1-module n) are connected to a load in parallel to supply power to the load, an SOC balance module considering SOH controls an active power set value # imgabs1 # of n inverters according to SOCi (SOC1-SOCn), SOH (SOH1-SOHn) and a power set value # imgabs0 # of the n energy storage inverter modules (module 1-module n), the active power set value # imgabs1 # is input into a virtual synchronous motor, and a phase # imgabs2 # corresponding to the ith energy storage inverter module is output; on the basis of a traditional VSG control strategy, power output of each converter is distributed more reasonably, when the current remaining electric quantity of the battery is low, the output power is reduced, over-discharge of the battery is avoided, and the service life of the battery is prolonged.

The invention discloses a sensorless control method for an electrically excited synchronous motor based on a rotor switching signal, and relates to the technical field of motor control, the inherent high-frequency modulation switching signal of an EESM rotor circuit (in a buck converter form) is utilized, and an effective stage (AS) and an ineffective stage (IAS) are divided based on the unipolarity characteristic of a rotor modulation voltage; a stator current gradient is directly calculated at the AS to extract position information, a fundamental current component is estimated at the IAS to be used for compensation, magnetic coupling saturation compensation and rotor PWM frequency optimization are combined, and full-rotating-speed sensorless control is achieved.

The alternating-current synchronous motor comprises a stator shell and a rotor, the stator shell is arranged on the ground, the rotor is arranged in the stator shell through an end cover and an insulating bearing, the rotor comprises a rotating shaft and a rotor iron core, the rotor iron core is arranged on the rotating shaft, and a tooth groove set is formed in the rotor iron core in a concave mode. The tooth groove group is composed of a plurality of adjacent tooth grooves, and the windings are arranged in the tooth grooves. The motor has the advantages that the relative positions of the stator and the rotor tooth grooves are collected through the rotor position sensor, the current of the three-phase alternating current and rated torque input are collected through the current sensor, the magnitude of the current of the three-phase synchronous alternating current is controlled, the torque of the motor is controlled, and winding arrangement is optimized, so that the reliability of the motor is improved. In the working process, the magnetic potential direction of the rotor is perpendicular to the magnetic potential direction of the stator at any position, then the maximum torque under the current is output, and meanwhile, the stator permanent magnet cannot be demagnetized due to the change of the magnetic field of the rotor.

The utility model provides a Wuyi rock tea multi-layer circulation rolling type spreading and cooling machine which comprises a supporting bottom plate, fixing plates are arranged at the left end and the right end of the upper surface of the supporting bottom plate, synchronous motors are embedded in the peripheries of the inner side faces of the fixing plates, gears are arranged on output shafts of the synchronous motors, and the gears are connected with the supporting bottom plate. The gears on the periphery are connected in a meshed mode through a cog belt to rotate, an air opening is formed in the fixing plate, and the air opening is connected with an air inlet hopper. A placing and spreading-cooling piece for placing tea leaves is arranged between the tooth-shaped belts at the left end and the right end; according to the utility model, tea leaves can be automatically turned over, and the ventilation uniformity and the spreading cooling efficiency are improved.

The utility model relates to the technical field of fan motors, in particular to a low-noise long-service-life fan motor which comprises a motor assembly and a shell assembly, the shell assembly is connected outside the motor assembly, and the motor assembly is composed of a fan motor, a sealing ring, a rotating shaft, a limiting strip, a fixing rod, a synchronous shaft and a synchronous motor. A rotating shaft is connected to the middle of the front face of the fan motor, a limiting strip is connected to the rotating shaft, a fixing rod is connected to the position, close to the middle of the front face, of the lower end of the fan motor, sealing rings are connected to the positions, close to the front face and the back face, of the exterior of the fan motor, and a synchronous motor is connected to the back face of the fan motor. The lower end of the synchronous motor is connected with a synchronous shaft, and the shell assembly is composed of a tail cover, a heat dissipation net, an insertion groove, an insertion sleeve, a heat dissipation fan, a shell, heat dissipation fins, an insertion ring, an end cover, a bearing, a limiting groove, an insertion strip and a noise reduction block.

To provide a method for estimating an axis error between a d-q axis and a γ-δ axis in a synchronous motor.SOLUTION: In a control method for driving a synchronous motor by sensorless vector control, a magnetic axis of a permanent magnet of the synchronous motor is defined as a d-axis, a direction orthogonal to the d-axis is defined as a q-axis, a designated magnetic axis of the synchronous motor is defined as a γ-axis, and a direction orthogonal to the γ-axis is defined as a δ-axis, and when vγ iγ+vδ iδ=P / 2 ωR ΦM iδ+R (iδ^2+iγ^2) is established, it is estimated that the d-q axis and the γ-δ axis coincide with each other without an error, and when the above expression is not established, an amount of the error is estimated from a difference between the left side and the right side. vγ represents a γ-axis voltage [V], iγ represents a γ-axis current [A], vδ represents a δ-axis voltage [V], iδ represents a δ-axis current [A], P represents a motor pole number, R represents a motor one-phase resistance value [Ω], ωR represents a motor electrical angular speed [rad / s], and ΦM represents a magnet flux [wb].SELECTED DRAWING: Figure 2