306 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 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 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 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.

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.

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.

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.

The invention relates to the technical field of high-speed generators, and discloses a double-three-phase fractional-slot winding carbon fiber reinforced high-speed generator and a design method.The double-three-phase fractional-slot winding carbon fiber reinforced high-speed generator comprises a permanent magnet synchronous motor, the permanent magnet synchronous motor adopts a double-three-phase winding surface-mounted topology and fractional-slot distribution winding, and a carbon fiber bundle is arranged on the surface of a rotor; the stator winding adopts a split transposition structure and is internally provided with an oil duct; and the controllable rectification controller adopts a three-phase two-level main power conversion topology and comprises a control circuit of a dual-digital signal processor redundancy architecture, a driving circuit of a multi-level driving architecture and a three-phase full-bridge silicon carbide main power circuit adaptive to a high-voltage multi-level topology. By adopting the dual three-phase fractional slot winding surface-mounted permanent magnet synchronous motor topology and cooperating with the split transposition winding structure, the winding circulation loss is reduced, the fault-tolerant capability is improved, and the rotor is bundled and reinforced by carbon fiber wires to counteract the high-speed rotation centrifugal force.

The invention provides an oil insulation three-phase integrated converter transformer system. The system comprises a converter valve provided with a diode valve, a direct current side outgoing line and a converter transformer valve side outgoing line, and a three-phase three-winding converter transformer provided with three-phase winding structures, and each phase winding structure comprises a network side outgoing line, a valve Y side outgoing line and a valve D side outgoing line; the top of the converter valve oil tank is provided with a direct-current sleeve, and the side wall of the converter valve oil tank is communicated with a converter valve side sleeve; the top of the transformer oil tank is provided with a network side sleeve, and the side wall of the transformer oil tank is communicated with a valve Y side sleeve and a valve D side sleeve; a plurality of converter transformer valve side sleeves are respectively butted and communicated with a plurality of valve Y side sleeves and a plurality of valve D side sleeves; an alternating current side outgoing line is connected with a valve Y side outgoing line and a valve D side outgoing line; and an AC-DC conversion system is formed among the converter valve oil tank, the transformer oil tank, the converter transformer valve side sleeve, the valve Y side sleeve and the valve D side sleeve. Through the current conversion system provided by the invention, the problems of low integration level, large equipment quantity, large size, large occupied area, high cost, complex structure, complex electrical connection and the like of the current conversion system are solved.

The invention discloses an energy storage type phase modifier with a damping structure and a system, and belongs to the technical field of electric power equipment. The brush doubly-fed motor comprises a stator and a rotor. An air gap is formed between the stator and the rotor; three-phase symmetrical windings are arranged in the stator and the rotor; the damping structure is made of an electric conductor material and is arranged along the circumference of the notch of the rotor; the damping structure can be equivalent to a three-phase winding, and in the equivalent three-phase winding of the damping structure, each phase is self-short-circuited. The damping structure optionally comprises at least one of the following structures: a slot wedge made of an electric conductor, a cage bar and an end ring. According to the invention, the energy storage type phase modifier has the capabilities of suppressing the excitation current peak value and improving the short-circuit current on the premise of ensuring the high inertia supporting function, so that an excitation system is effectively protected, and the short-circuit voltage supporting capability of the motor is enhanced.

The application discloses a five-seventh harmonic suppression method suitable for a twelve-phase motor, four sets of three-phase currents of a twelve-phase propulsion system are collected to obtain twelve alternating currents; two sets of three-phase windings of the twelve-phase motor with a phase difference of 30 degrees are taken as a whole, five-seventh harmonic amounts of the two sets of three-phase currents with a difference of 30 degrees are converted into direct currents by using a six-phase park conversion matrix; the output amounts of the direct currents obtained by a PI regulator are combined with the direct currents on a fundamental wave plane, and the alternating currents calculated by using a six-phase park inverse conversion matrix are taken as corresponding modulation waves of each channel respectively. The application is simple and easy to implement, has strong universality, has good five-seventh harmonic suppression effect, and is easy to be popularized to other multi-phase motor system harmonic suppression occasions.

The invention discloses a permanent magnet synchronous motor parameter identification method, device and equipment and a storage medium, and relates to the technical field of motor parameter tuning, and the method comprises the steps: constructing a voltage equation model under a synchronous rotating coordinate system under a field oriented control (FOC) frame, and injecting a sweep frequency signal to a d-axis voltage Ud and a q-axis voltage Uq of a permanent magnet synchronous motor; converting the sweep frequency signal into a three-phase PWM waveform through Park inverse transformation and space vector pulse width modulation, and applying the three-phase PWM waveform to a three-phase winding of a motor stator; three-phase current of a stator is collected, and d-axis current Id and q-axis current Iq are obtained through Clark conversion and Park conversion; fourier transform is carried out on the input sweep frequency signal and the output current signal, a time domain signal is converted into a frequency domain signal, and amplitude frequency and phase frequency data of the input signal and the output signal are obtained; and establishing an objective function based on amplitude-frequency and phase-frequency data, performing iterative optimization solution on the stator resistance Rs, the d-axis inductance Ld and the q-axis inductance Lq by using a genetic algorithm, and outputting an optimal parameter identification result.

The invention relates to the technical field of power-assisted bicycles, and discloses a power assembly for a power-assisted bicycle and the power-assisted bicycle. The powertrain includes an epicyclic gear train including a first gear element, a second gear element, and a third gear element; the middle shaft is coupled with a pedal of the power-assisted bicycle; the first motor is coupled with the epicyclic gear train through a first gear element; the second motor and the middle shaft are coupled and connected with the epicyclic gear train through a second gear element; an output crankset coupled with the epicyclic gear train through a third gear element; the detection module is connected with the first motor and used for detecting working electrical parameters of the first motor; the control module is connected with the detection module and the second motor and used for controlling a three-phase winding of the second motor to be short-circuited and increasing the rotation resistance of the second motor under the condition that the working electrical parameters of the first motor are not matched with the preset rotation parameters of the first motor, so that the treading resistance of the pedal is increased, and the purpose of preventing a user from missing steps is achieved. And the riding experience of the rider is improved.

A flat wire motor stator structure disclosed by the present invention comprises a stator iron core and flat wire hairpins inserted into the stator iron core, the plurality of flat wire hairpins are mutually connected to form a three-phase winding of a motor: 54 stator grooves are formed in the inner ring surface of the stator iron core at equal intervals, and six layers of flat wire hairpins are inserted into each stator groove in the radial direction; each phase winding is provided with three parallel branches, the winding sequence of each parallel branch is the same, and each parallel branch is composed of five types of flat wire hairpins. The motor comprises the flat wire motor stator structure. The stator structure of the flat wire motor ensures the slot filling rate of a motor assembly in a limited space, and improves the power density and efficiency of the motor; and only five types of flat wire hairpins are adopted, so that the mold opening cost during production is reduced, and the production time is shortened.

The application provides a stator of a flat wire motor and the flat wire motor, the slot number of each pole and each phase of the stator is 3, the pole number of the stator is an even multiple of 3, the layer number formed by the flat wire stator winding in the winding slot is 2M, M is an even number greater than or equal to 2; the winding comprises a three-phase winding, each phase winding comprises two parallel branches, each branch is formed by a plurality of U-shaped sub-conductors in series; each phase winding comprises a plurality of conductor groups, each conductor group comprises three sub-conductors, and the span is K+1, K and K-1 respectively; each sub-conductor spans two adjacent layers, which are the 2N layer and the 2N-1 layer respectively; the slots occupied by the sub-conductor are in the M layers located on the radial inner side, three continuous inner slots are occupied by each pole and each phase, three continuous outer slots are occupied by each pole and each phase in the M layers located on the radial outer side, and the three inner slots and the three outer slots of each pole and each phase are staggered by one slot position in the circumferential direction. According to the stator structure, the manufacturing cost is low, the harmonic influence is small, and the working performance is good.

The utility model provides a 72-slot 8-pole 6-layer full pitch flat wire winding stator and motor, which comprises an iron core, the iron core comprises a body and a plurality of accommodating slots, the body is of a hollow annular structure, stator windings are uniformly arranged in the accommodating slots along the inner surface of the body at intervals, each stator winding comprises a three-phase winding arranged on the iron core, the number of slots per pole per phase is 3, and the number of slots per pole per phase is 3; the three-phase winding forms a six-layer structure which is sequentially arranged in the radial direction of the iron core, and each phase winding can form three winding branch structures which are mutually connected in parallel. According to the utility model, through cross-layer linear combination, ring current in the winding is effectively reduced, so that the operation stability and reliability of the motor are improved. The simplified design of the outer layer connecting part not only reduces the processing strength, but also shortens the production cycle. Most importantly, the optimization measures act together, and the operation efficiency of the motor is remarkably improved.

The invention discloses an intelligent zipper system, which comprises a zipper tape provided with a plurality of zipper teeth; the zipper head is movably arranged on the zipper tape, and a permanent magnet array is arranged in the zipper head; the driving system comprises a three-phase winding arranged on the sprocket; the position detection system is used for detecting the position of the zipper head in real time; the control unit is used for controlling the power-on state of the three-phase winding, the control unit controls the three-phase winding to generate a moving magnetic field according to a feedback signal of the position detection system, and the permanent magnet array is driven to drive the chain head to move; the power supply system supplies power to the driving system and the control unit; the rectifying device is used for converting direct current into alternating current to generate a magnetic field for the three-phase winding; the system has an electric mode and a power generation mode, and in the electric mode, the chain head is driven to move to achieve automatic opening and closing; in the power generation mode, the chain head is manually pulled to enable the permanent magnet array and the three-phase winding to move relatively to generate induction current, and the induction current is rectified and stabilized to charge the energy storage device or supply power to the load.

The invention provides a controller for controlling engine suspension of a hybrid power vehicle at low cost and the vehicle, relates to the field of new energy vehicles, and can be applied to the hybrid power vehicle. The controller comprises a shell, a motor power circuit and a control circuit, wherein the shell comprises a motor connecting interface and an engine suspension connecting interface; the motor power circuit comprises three phases of bridge arms, and bridge arm midpoints of the three phases of bridge arms of the motor power circuit are used for being connected with three phases of windings of a motor through motor connection interfaces respectively. The control circuit is used for being connected with an engine mount through the engine mount connecting interface, and the engine mount is used for fixing an engine of the hybrid power vehicle; and the control circuit is used for controlling the engine mount to act. According to the scheme, an additional engine suspension controller does not need to be added, and the control function of the engine suspension is integrated into the MCU or the GCU or the two-in-one controller, so that the cost of the whole vehicle can be reduced, and the engine suspension can be effectively controlled to weaken the NVH of the vehicle.

The utility model discloses an integral pitch winding stator, which comprises an iron core and a stator winding wound on the iron core, 48 stator slots are arranged on the iron core at intervals, a plurality of wire layers are respectively arranged in each stator slot, the wire layers in each stator slot are sequentially arranged from inside to outside along the radial direction, and the stator winding is a three-phase winding; each phase winding comprises four parallel branches, each branch comprises a first leading-out end and a second leading-out end, the first leading-out ends of the branches in the same phase are respectively connected to different wire layers in the same stator slot, and the second leading-out ends of the branches in the same phase are respectively connected to different wire layers in the same stator slot. And the first leading-out end and the second leading-out end are respectively led out of different stator slots. In the four branches of each phase winding, each first leading-out end is led out from the same stator slot, and each second leading-out end is led out from the same stator slot, so that only two stator slots of each phase are provided with the leading-out ends, the wiring is simple, and the circuit is neat after wiring.

The utility model relates to the field of cooling and ventilation of transformers, in particular to a dry-type transformer. The dry-type transformer is used for solving the problems that a refrigeration fan of an existing dry-type transformer is prone to being damaged, when the refrigeration fan is damaged, the refrigeration fan needs to stop running and be overhauled, and normal running of the dry-type transformer is affected. The dry-type transformer comprises a control system, a bottom foot, a lower clamping piece and a three-phase winding, the lower clamping piece and the three-phase winding are installed on the bottom foot, a ventilation air channel is formed between a high-voltage winding and a low-voltage winding of each phase winding, a first refrigeration fan unit is arranged on the lower clamping piece, an air opening of a refrigeration fan of the first refrigeration fan unit faces the ventilation air channel, and a second refrigeration fan unit is further installed on the bottom foot. The first refrigerating fan unit and the second refrigerating fan unit are both connected with the control system, and the refrigerating fan units serve as backups for each other, so that when one refrigerating fan unit breaks down, the other refrigerating fan unit can work under the control of the control system. And continuous cooling of the transformer is ensured.