446 results about "Three phase windings" patented technology

The invention discloses an open-phase self-fault-tolerant control method for a phase-shift-free dual three-phase permanent magnet synchronous motor. The method can automatically adjust a current distribution relation in the case of an open-phase fault and suppress torque pulsation in combination with neutral point voltage compensation. Comprising the following steps: driving two pairs of three-phase winding modules of the phase-shift-free DTP-PMSM in parallel by adopting two two-level three-phase voltage source inverters, and providing a mathematical model of the motor; current distribution is automatically adjusted; compensating the voltage of the neutral point, and calculating the offset of the fault module; the current is redistributed to suppress the torque ripple after the fault, and the secondary oblique wave component generated by the phase failure fault is eliminated; a current loop controller is improved through dead-beat predictive control; the speed ring controller is optimally designed into an improved sliding mode controller; an improved double-loop controller system is formed by combining improved sliding mode control and dead-beat prediction control, high-gain parameters are set to improve the dynamic response performance of the system, and a new self-fault-tolerant control system is formed.

The invention provides a motor drive control method and system for a high-speed hair dryer. The method comprises the following steps: acquiring a real-time sampling value of bus voltage; when the real-time sampling value reaches a preset voltage threshold value, performing vector operation on a torque current integral value of the motor current, and determining an initial position angle of a rotor; performing Clark transformation on the three-phase winding endpoint voltage according to the initial position angle of the rotor to generate a voltage component; determining a wind power interference coefficient of the torque current according to the voltage component, and determining a corresponding wind power state identifier in combination with a preset threshold value; configuring a sliding-mode observer according to a starting parameter group of a motor starting control mode corresponding to the wind power state identifier, and determining a rotor motion state parameter by performing phase tracking on output of the sliding-mode observer; and generating a three-phase pulse width modulation driving signal through the rotor motion state parameters to perform driving control on the motor. According to the scheme, the starting reliability and control precision of the motor can be remarkably improved, and the service life of the blowing cylinder is effectively prolonged.

The invention belongs to the related technical field of motor winding design, and discloses a design method of an alternating current winding capable of generating multipolar magnetomotive force, which comprises the following steps of: selecting n three-phase symmetrical winding units according to n required magnetomotive forces and determining the number of fundamental wave pole pairs, performing star connection on three-phase windings in each three-phase symmetrical winding unit, the same-phase windings of the n three-phase symmetrical winding units are connected in series to form a winding assembly, and star connection is kept; according to the fundamental wave pole pair number of each three-phase symmetric winding unit, determining the arrangement of the corresponding three-phase symmetric winding unit in the iron core slot, and obtaining the initial arrangement of the winding assembly in the slot; and based on the equal ampere-turn principle of the alternating current winding, combining and simplifying the winding coil conductor in each slot to obtain the final arrangement of the winding assembly in the slots. An alternating current winding is designed based on the method, useless harmonic components can be suppressed, and various principal wave magnetomotive forces with any number of pole pairs and any turning direction can be generated.

The invention discloses a function switching device for transformer testing and a testing system thereof, relates to the technical field of transformer testing, is used for solving the problem of low testing efficiency, and is used for setting a switching time reference by acquiring transformer capacity information and detecting the number of closed relays of testing nodes and loop resistance. Analyzing a resistance fluctuation index and loop harmonic characteristics by combining historical loop resistance data, correcting a switching time reference, detecting three-phase winding current, generating a current balance index, evaluating a fault risk level, screening and marking to-be-tested nodes according to the fault risk level, and after the current test node is tested, determining the current test node according to the fault risk level. And performing test processing on the marked to-be-tested nodes based on the corrected switching time reference, thereby realizing intelligent selection of a transformer test sequence, improving test efficiency and ensuring electrical state stability and test precision of each test node.

The invention provides a motor stator temperature estimation method and device, electronic equipment and a storage medium, and relates to the technical field of motors, and the method comprises the steps: injecting positive and negative alternating DC voltage signals into a motor under a static coordinate system; obtaining a current signal of a three-phase winding of the motor, and obtaining a direct current component of current according to the current signal; obtaining a resistance value of a motor stator winding according to the DC component and the DC voltage signal; and obtaining the stator temperature according to the resistance value so as to accurately estimate the stator temperature.

The invention discloses a permanent magnet synchronous motor harmonic current separation method constructed based on a virtual winding, and relates to the technical field of motor control, and the method comprises the steps: building a generalized constraint condition of harmonic current separation, and carrying out the harmonic current separation based on the generalized constraint condition of harmonic current separation and the order of a harmonic current needing to be separated, determining the construction number of virtual windings and space intervals among the virtual windings; sampling three-phase current in a three-phase winding of the permanent magnet synchronous motor; based on the construction number of the virtual windings and the space intervals among the virtual windings, constructing the virtual windings to obtain three-phase current in each virtual winding; and based on the three-phase current in each virtual winding and the three-phase current in the three-phase winding of the permanent magnet synchronous motor, constructing a harmonic current separation expression to realize the separation of the harmonic current of the permanent magnet synchronous motor. According to the method, accurate separation of the fundamental current and the harmonic current of any frequency is realized, and a good basis is provided for subsequent control of the harmonic current.

The present invention provides a three-phase terminal block, a drive assembly and a vehicle, including a terminal block body and three single-phase terminal posts. The terminal block body extends in a cylindrical shape, and the three single-phase terminal posts are arranged along the axial direction of the terminal block body. The three single-phase terminal posts are provided on the outer periphery of the terminal block body, and a first terminal and a second terminal are respectively arranged at both axial ends of the single-phase terminal post on the terminal block body. Since the stator has a three-phase winding, the three single-phase terminal posts are arranged on the outer periphery of the terminal block body, and then the three single-phase terminal posts can be correspondingly connected to the terminal ends of the stator, thereby optimizing the wiring layout, and the space between the three single-phase terminal posts can be used to place spaces such as bearings, thereby improving the compactness of the structural layout.

The invention discloses a stator and rotor dual three-phase winding motor, which belongs to the technical field of motors and comprises a stator, a rotor and an air gap. An air gap exists between the stator and the rotor according to the number of rotor teeth; the tooth number stator of the rotor teeth comprises stator teeth, stator windings, stator permanent magnets and stator yokes, the tooth number stator windings of the rotor teeth are three-phase windings and are wound on the stator teeth, stator grooves are formed between adjacent stator teeth, and the stator permanent magnets are placed in the stator grooves; the tooth number rotor of the rotor teeth comprises rotor normal teeth, rotor teeth, rotor permanent magnets and a rotor yoke part, the tooth number rotor teeth of the rotor teeth are divided into rotor split teeth and normal teeth, every two rotor normal teeth and one rotor split tooth form a group of rotor teeth, and a plurality of groups of rotor teeth are sequentially arranged and uniformly distributed along the circumferential direction; the tooth number rotor winding of the rotor teeth is a three-phase winding and is wound on the rotor teeth; the rotor grooves are formed between the adjacent rotor teeth, and the rotor permanent magnets are placed in the rotor grooves, so that the reliability and the fault-tolerant capability of the motor are improved.

The present disclosure proposes a stator assembly including a stator core including an annular stator yoke and a plurality of stator teeth connected to a radially inner side of the stator yoke, the plurality of stator teeth being spaced apart from each other in a circumferential direction; each phase of winding comprises a first coil group and a second coil group, each stator tooth is wound with one first coil and one second coil, the first coil group comprises at least one first coil, and the second coil group comprises at least one second coil; the first coil of the first coil group and the second coil of the second coil group are wound on the same stator teeth; three first terminals, wherein the first coil group of the three-phase winding is electrically connected to one of the three first terminals; and three second terminals, wherein the second coil group of the three-phase winding is electrically connected to one of the three second terminals. And the first terminals and the second terminals are electrically connected in pairs, so that the first coil group and the second coil group in each phase winding are connected in parallel.

The invention discloses a generator stator winding single-phase earth fault positioning method, system and device and a medium, and the method comprises the steps: enabling three phases of a generator stator winding to be connected in series end to end to form a series loop; low-frequency voltage pulses are injected into the three-phase winding, and a fault phase is determined by comparing symmetry damage characteristics of tail-end current by adopting a tail-end current vector analysis method; injecting a low-frequency voltage pulse into the current phase winding, detecting the current difference between the head end and the tail end of each parallel branch, identifying a branch with abnormal leakage current by combining a leakage current characteristic analysis method, and determining a fault branch; establishing a high-frequency distribution parameter model, and performing high-frequency voltage pulse injection positioning for multiple times to obtain three independent high-frequency pulse positioning results; and performing weighted fusion on the three independent high-frequency pulse positioning results, and performing optimization by using an intelligent optimization algorithm to obtain an optimized single-phase earth fault position. According to the invention, the accuracy and rapidity of fault diagnosis and positioning can be improved.

The invention relates to the technical field of electro-hydraulic integrated driving, in particular to a hydraulic synchronous control system and method based on traveling wave and magnetic field composite driving, the system comprises a plurality of hydraulic cylinders, and each hydraulic cylinder comprises a piston rod assembly and a cylinder barrel; the piston rod assembly comprises a metal push rod on the inner layer, a three-phase winding module arranged around the metal push rod on the middle layer and a lining barrel on the outer layer. Each hydraulic cylinder corresponds to one pressure sensor, one displacement sensor and one controller. The cylinder barrel serves as a secondary conductor, eddy current is generated through traveling wave magnetic field induction, and axial thrust is generated. In a no-load state, the controller switches the current direction to generate auxiliary oil absorption thrust; during loading, current parameters are dynamically adjusted according to displacement, pressure and speed feedback, and synchronous compensation and speed regulation are achieved. The linear motor has the characteristics of high thrust density of a hydraulic system and quick response of the linear motor, and is suitable for high-precision engineering machinery and aerospace hydraulic actuating mechanisms.

The invention relates to a quick charge boost control method and device for a vehicle, the vehicle and a storage medium. Comprising the steps of obtaining a system state and a power battery charging power demand of a current vehicle when the current vehicle has a quick charge boosting demand, and generating an initial charging current instruction according to the system state and the power battery charging power demand; obtaining a final charging current instruction based on a preset first PI regulator according to the initial charging current instruction, obtaining a three-phase winding neutral point output current instruction based on a preset second PI regulator according to the final charging current instruction, and obtaining a three-phase winding neutral point output current instruction based on a preset third PI regulator. And obtaining a duty ratio control instruction of a three-phase bridge arm according to the three-phase winding neutral point output current instruction, and performing interleaving control on a three-phase upper bridge arm of the motor controller power module according to the duty ratio control instruction of the three-phase bridge arm. Therefore, the problems that the unexpected torque is easy to realize and the charging efficiency is relatively low in the prior art are solved, and the charging efficiency is improved while the safety is improved.

The application provides a method for pulse heating a power battery of an electric vehicle and the electric vehicle. The electric vehicle comprises a plurality of motors and a plurality of three-phase bridge arms. A bridge arm midpoint of each three-phase bridge arm is used for connecting three-phase windings of one motor. Each three-phase bridge arm is used for connecting the power battery through a direct current bus. The control method comprises: controlling each three-phase bridge arm to generate a pulse current on the direct current bus; and adjusting a switching frequency of a switching tube of at least one three-phase bridge arm of the plurality of three-phase bridge arms to reduce a phase difference of the pulse currents generated by the plurality of inverter circuits. The phase value of the pulse current output by the at least one three-phase bridge arm is adjusted, so that the phase difference of the pulse currents generated by the plurality of three-phase bridge arms is reduced, and the heating efficiency of the power battery is improved.

Three-phase windings are wound, with a conductor, around twelve magnetic pole teeth arranged at equal angular intervals on an inner peripheral portion of a stator core configured to constitute a three-phase, twelve-pole stator. The winding of each phase comprises, at least at one location, a portion in which the conductor is drawn out from one of the slots to form a lead-out portion and is then returned to the same slot, and the conductor on both sides of the lead-out portion is fixed within the one slot by the conductor wound around one of the magnetic pole teeth forming the one slot after the lead-out portion has been formed.

This invention relates to a current reconfiguration method for a 30° phase-shift angle dual three-phase permanent magnet synchronous motor, solving the problem that a DTP-PMSM current reconfiguration control system requires a single current sensor to be inserted through three or more branches. It falls within the field of motor drives. The invention utilizes a single current Hall sensor to collect the sum of the current between the lower bridge arms of phases A and B of the first three-phase winding and the current between the upper bridge arms of phases X and Y of the second three-phase winding. SAMPLE Based on the sampling method, modulation method, and spatial distribution characteristics of the two sets of motor windings, a reconstructed region is constructed, and a six-phase current reconstructed expression for the motor in each reconstructed region is generated. A combination of IPWM and variable sampling timing is used to eliminate the blind zone at the boundary of the reconstructed region. Based on the reconstructed region where the reference voltage vector is located and the real-time acquired IPWM signal... SAMPLE Select the appropriate six-phase current reconstruction expression to reconstruct the six-phase current.

An electric assembly includes a box body, an electric control module, and a motor. The electric control module is disposed in the box. The motor is disposed on the box. The motor includes: a casing, a N wire connection assembly, an end cover, and three phase windings. A first end of the N wire connection assembly is configured to connect to a battery pack. The end cover is disposed at one end of the casing and configured to close the casing, and includes an opening that allows a part of the N wire connection assembly to pass through. The three phase windings are disposed in the casing. First ends of the three phase windings are connected with the electric control module, and second ends of the three phase windings are connected with a junction and connected with a second end of the N wire connection assembly.

The present invention discloses a magnetic levitation permanent magnet speed regulator based on a magnetic levitation linear motor and a speed regulation method thereof. The magnetic levitation linear motor comprises a cylindrical magnetic levitation linear motor, an axial single-degree-of-freedom hybrid magnetic bearing, and a dual cylindrical permanent magnet regulator. The control coil of the axial single-degree-of-freedom hybrid magnetic bearing is always energized, keeping the mover in a suspended state. The three-phase winding coils of the cylindrical magnetic levitation linear motor are energized according to changes in the external load to generate thrust that causes the mover to move axially, thereby driving the stator of the axial magnetic bearing to move axially. The axial air gap changes of the axial magnetic bearing are detected, and the axial magnetic bearing is controlled to generate a magnetic attraction that causes the magnetic bearing rotor to move axially, driving the sleeve on the transmission shaft to move linearly, changing the contact surface between the permanent magnet regulators, and adjusting the output torque and speed. The magnetic levitation permanent magnet speed regulator proposed by the present invention achieves more precise speed control, ensuring high-efficiency transmission. It also reduces vibration and noise, optimizes the permanent magnet regulator, and extends the service life of the equipment.

The invention discloses a vehicle-mounted range extending system, a vehicle and a charging method of the vehicle, and the vehicle-mounted range extending system comprises an ACDC circuit, a three-phase winding of a generator, a first switch unit, a vehicle-mounted charging unit and a second switch unit; a three-phase winding of the generator is connected with the ACDC circuit through the first switch unit, so that the three-phase winding of the generator is controlled to be communicated with the ACDC circuit; the vehicle-mounted charging unit is connected with the ACDC circuit through the second switch unit so as to control the on-off of the three-phase winding of the generator and the ACDC circuit; under the condition that the first switch unit is in an open state and the second switch unit is in a closed state, the vehicle-mounted range extending system is in an alternating current charging state, and the ACDC circuit is used for rectifying and outputting received alternating current electric energy to a battery pack of a vehicle; the device is simple in structure, low in charging loss and low in improvement cost.

The invention provides a power supply mode switching method and device, a vehicle and a storage medium, and relates to the field of high-voltage power supply. And when the motor supplies power to the whole vehicle and the power supply for supplying power to the whole vehicle needs to be converted from the motor to the high-voltage battery, the motor is controlled to stop generating power. Therefore, when the motor and the high-voltage battery are a high-voltage power supply, the high-voltage battery is regarded as a load, and the battery relay of the high-voltage battery is closed, the battery relay is prevented from being damaged. After the motor stops generating power, the motor is in a driving mode, the motor cuts a stator winding due to residual magnetism and generates back electromotive force with residual inductance, and when the back electromotive force is large, the motor enters a three-phase parallel common-path active discharge mode, so that the current of the three-phase winding is multiplied. And when the current of the three-phase winding is multiplied, the back electromotive force is rapidly reduced, and the rapid discharge of the back electromotive force can be realized. After the motor enters the active discharge mode, the counter electromotive force is detected, so that the battery relay of the high-voltage battery is closed when the counter electromotive force is small, and the error switching risk when the active discharge mode does not reach the expectation is avoided.

The invention relates to the technical field of asteroid motion simulation, and discloses a simulation experiment device suitable for a gravel pile asteroid, the simulation experiment device comprises a vacuum assembly, a suspension assembly, an objective table, a three-phase winding and a camera, the suspension assembly is arranged in the vacuum assembly, and the objective table is arranged at the top of the suspension assembly; the objective table is used for placing a gravel pile asteroid simulant, a three-phase winding is further arranged on the objective table, and a camera is arranged in the vacuum assembly, located at the top of the gravel pile asteroid simulant and used for shooting the movement condition of the gravel pile asteroid simulant; the gravel pile asteroid simulant is placed on the objective table and is in a vacuum state, the gravel pile asteroid simulant is suspended and rotated through the suspension assembly and the three-phase winding, the movement condition of an asteroid in a real state can be simulated, recording can be carried out through the camera, and follow-up observation and analysis are facilitated.

A DFIG wind power facility configured to be operated during grid faults is provided. The wind power facility includes a Doubly-Fed Induction Generator, a control system, an electric converter, a short-circuit controlled switch to selectively short-circuit the stator and a Stator Neutral Brake Chopper coupled to the stator. The DFIG includes a rotor and a stator, the stator including at least one three-phase winding. The electric converter includes a Machine Side Converter, a Grid Side Converter and a DC link connected therebetween. The SNBC includes a three-phase rectifier including three inputs, an impedance and an active high-frequency switch configured to vary the average value of the impedance by adjusting its duty cycle; each of the three inputs of the rectifier is connected to a phase of the at least one three-phase winding of the stator. Methods for operating a DFIG wind power facility during grid faults are also provided.

The invention relates to an axial magnetic flux second-order three-phase end winding process design and manufacturing method, in particular to a second-order three-phase winding motor process design and manufacturing method aiming at further improvement of a previously applied and existing motor, and unifies in-slot windings of a previously applied high-order winding and a previously applied low-order winding in the same radial space. In other words, all the in-groove windings are evenly distributed in the same diameter area concentric with the air gap, only the end windings are divided into the high-order end windings and the low-order end windings, and the performance of the motor is further optimized; the winding is characterized in that the winding has an effective winding advantage that the end winding participates in excitation and has an equivalent function with an in-slot winding, the end winding has better heat dissipation and heat conductivity, and the winding has no crossing problem of windings of different phases, so that the voltage-withstanding safety of the winding is greatly improved, and the winding forming process is simplified.

The invention relates to the technical field of new energy automobiles, in particular to a common positive bus multiplexing motor winding inductance boosting and current increasing heating system which comprises a power battery, a charging port, a driving system and a switch assembly. The power battery is provided with a self-heating loop, and positive and negative electrodes are connected with the charging port through a positive bus and a negative bus respectively to realize a battery self-heating mode; the driving system comprises a motor and a motor controller arranged between a positive bus and a negative bus, and the motor is provided with a three-phase winding inductor which is respectively connected to different transistors of the motor controller. The switch assembly is connected with two-phase winding inductors of the motor in parallel, one-phase winding inductors are connected in series, and the switch assembly comprises a plurality of switches arranged on positive and negative buses and is used for controlling the motor inductor to be connected with at least one of the negative electrode of the power battery, the negative electrode of the charging port or the positive bus, and the motor inductor is reused to achieve a direct fast charging mode, a boost charging mode or an up-current charging mode. Therefore, the problem that the electric vehicle is difficult to be compatible with charging piles of different voltage grades is solved.

A motor drive device is connected to a motor having three phase windings, and includes a switching circuit and a controller. The switching circuit includes a plurality of series circuits of switching elements on the upstream side and switching elements on the downstream side along the application direction of the DC voltage, and the respective phase windings are connected to the mutual connection points of the switching elements of the series circuits. The controller determines the short circuit of each phase winding on the basis of the state of the current flowing between the switching circuit and the motor while sequentially switching a plurality of current paths through which the current flows in a prescribed direction of each phase winding through each switching element.

The invention discloses a tubular linear motor for a hybrid suspension actuator, and relates to the technical field of automobile suspensions, the tubular linear motor comprises a piston cylinder body, a piston rod body and a magnetorheological damper, a three-phase winding coil is wound on the inner wall of the piston cylinder body, the piston rod body is connected with the piston cylinder body in a sliding fit manner, and a plurality of annular magnetic steels are fixedly arranged on the outer side of the piston rod body; the annular magnetic steel is arranged in the axial direction of the piston rod body, the polarities of the adjacent annular magnetic steel are opposite, the three-phase winding coils and the annular magnetic steel are arranged in the radial direction, one end of the magneto-rheological damper is fixedly connected with the piston cylinder body, and the other end of the magneto-rheological damper is connected with the piston rod body in a sliding fit mode. In the design, radiation radial magnetization is selected as a magnetic steel magnetizing scheme, and compared with axial magnetization, effective magnetic flux and motor output can be increased on the thrust density of unit volume; in the aspect of energy consumption, current and copper consumption of a primary coil can be reduced; and the influence of magnetic leakage of a main magnetic field on the damper can be isolated, and the actual use condition is better met.

The utility model discloses a same-slot and same-phase winding structure, a motor stator and a flat wire motor. The same-slot and same-phase winding structure comprises a three-phase winding, a leading-out end and a neutral end, the single-phase winding is an integral pitch winding and comprises a first branch and a second branch, the first branch and the second branch are alternately distributed in the radial direction and fill the same stator groove, and the two branches comprise U-shaped hairpins with the two ends located at the groove bottom and the groove opening of the stator groove and U-shaped hairpins with the two ends crossing adjacent layers and not located at the groove bottom and the groove opening of the stator groove; the two branch leading-out ends are respectively located at the bottom or the notch of the stator slot, and the radial distances between the two branch leading-out ends and the neutral end are the same. According to the utility model, the single-phase winding is arranged to be a winding structure with the same slot and the same phase, so that the insulation breakdown risk is reduced; the shape of the formed unidirectional winding hairpin is uniform, and the hairpin processing complexity is reduced; the positions of the leading-out ends of the first branch and the second branch of the three-phase winding are concentrated to reduce the use of wrapping insulating materials, so that the manufacturing cost is reduced; the hairpin bending parts are the same, so that the torsion distances of the welding ends are the same, and the welding process complexity is reduced.

Motor for use in a washing machine, comprising: a stator (100), comprising: a core (108) made of magnetically permeable material, comprising an annular ring section (104) having an inner diameter of 120 mm to 250 mm and a radial width (134) of 5 mm to 15 mm, 27 radially extending poles (102) spaced apart around the outer circumference of the annular ring section (104), the poles (102) extending outwards from the annular ring by a distance of 15 mm to 40 mm, three phase windings, each winding comprising a plurality of coils arranged on one third of the pole cores (109), the windings on the pole cores (109) being arranged such that each pole core (109) is assigned only one winding, which is different from the winding assigned to each of two immediately adjacent pole cores (109). is,and the two immediately adjacent pole cores (109) are assigned to different windings, an insulator that insulates the pole cores from the windings, a rotor (36) that is concentric to the stator (100), with a permanent magnet ring (38) outside the stator (100) and rotor poles that point towards the ends of the stator poles (102), wherein the ratio of rotor poles to stator poles (102) is 4:3.

The invention provides a fault-tolerant control method and system for open-phase faults of a four-phase and three-phase permanent magnet synchronous motor, electronic equipment and a storage medium. Belongs to the technical field of motor control. The method is based on a 4DQ decoupling control framework, and an open-phase fault-tolerant control module is additionally arranged between a speed loop and a current loop. When the open-phase fault of the motor is detected, the module firstly identifies the number of sets of faulty windings, cuts off control signals of the faulty sets of windings, then averagely distributes q-axis total reference current output by a speed ring to the remaining healthy three-phase windings again according to the number of the faulty sets, and carries out necessary amplitude limiting processing. And finally, the current loop controller of each healthy winding drives the inverter to work according to the redistributed reference current. According to the invention, the structural advantage of independent isolation of the four-phase and three-phase motor windings is fully utilized, and the torque ripple is effectively suppressed and the stable operation of the motor is maintained through overload or derating operation of a healthy winding under the condition that a single set or multiple sets of windings have faults.

The utility model relates to a compressor motor insulation reel which is especially suitable for a motor with a three-phase winding adopting angle connection. The winding frame comprises an annular body, and nine winding parts are arranged on the inner side of the annular body in the radial direction. Three wide winding openings and three narrow winding openings are formed in the upper portion of the annular body, the width T of the wide winding openings is larger than the width t of the narrow winding openings, and the wide winding openings are head end outlets and tail end outlets of three-phase winding leads of the motor respectively. And three lead limiting clamps with downward openings are arranged near the three winding wide openings and are used for fixing the head ends of the leads and preventing the leads from loosening or falling off. Seven lead limiting protruding parts are arranged on the radial outer side of the annular body and distributed at different horizontal heights to form high and low distribution at different horizontal heights, and the lead limiting protruding parts are used for separating leads of windings of different phases and preventing virtual connection or short circuit. According to the utility model, the electrical performance and the mechanical stability of the motor are improved by optimizing the lead management and the winding design, and the motor has the advantages of simple structure, convenience in operation and high reliability.

A motor drive device connected to a motor having three phase windings comprises a switching circuit and a controller. The switching circuit includes a plurality of series circuits of switch elements on an upstream side along a direction of application of a DC voltage and switch elements on a downstream side, and the phase windings are connected to interconnection points of the switch elements in these series circuits. The controller sequentially switches a plurality of conduction paths through which current flows in a predetermined direction of the respective phase windings through the respective switch elements, and determines whether there is a short-circuiting in each of the phase windings based on the state of the current flowing between the switching circuit and the motor.