78results about How to "Reduce stray loss" patented technology

The present invention discloses a magnetic suspension flywheel battery for a sandwich-type electric car and a work method thereof. A vertical rotation shaft is arranged at the center of the internal portion of a vacuum chamber, a disc-type flywheel motor is coaxially arranged at the center of the axial direction of the vertical rotation shaft, disc-type magnetic bearings having the same structure, being arranged at the axial direction in the longitudinal symmetry mode relative to the disc-type flywheel motor and being sleeved at the outer portion of the vertical rotation shaft are coaxially arranged at the upper portion and the lower portion of the disc-type flywheel motor, and each disc-type magnetic bearing is wound with a set of radial control coils; the disc-type flywheel motor is composed of a stator, two rotors and two sets of permanent magnets, the stator is located at the center of the disc-type flywheel motor and coaxially arranged at the outer portion of the vertical rotation shaft, and the two rotors are respectively and symmetrically arranged at upper and lower sides of the stator and coaxially and fixedly sleeved on the vertical rotation shaft; and the two sets of the permanent magnets are respectively pasted on the surfaces, back to the stator, of the two rotors along the peripheral directions, the whole structure of the flywheel battery is a disc-type structure, the disc-type magnetic bearings and the disc-type flywheel motor are both the flat structures to inhibit the gyroscopic effect of the rotors.

This invention relates to a motor rotor surface pickling technique which is applied in reducing the iron loss and stray load loss in cage induction motor rotors. It is unique that rotors not eligible in frequency testings are screened out for pickling at first and then processed as follows. Firstly, the rotor is lathed by 0.10mm in outer circle. Secondly, hydrochloric acid and water are mixed into solution at a ratio of 1:1. Thirdly, the whole outer circle surface of the rotor is treated with hydrochloric acid solution. Fourthly, the entirely treated rotor is placed into an oven for drying without definite time limitation. This invention beneficially reduces the stray load loss to 1 / 5 of the original value at most and promotes the motor efficiency, typically by 0.5~1.5% for middle or small low-voltage motors.

The invention discloses a stator assembly and a motor equipped with same, a compressor, and refrigeration equipment. The stator assembly comprises a stator iron core, and a stator winding, wherein the stator iron core is equipped with multiple stator grooves; the number of the stator grooves is Q which is multiple of 4; the stator winding comprises a main winding and a secondary winding; in the same pole of the main winding, the number of the stator grooves in the same-side effective edge of each coil is km; the sum of the wire-winding sectional areas of the same-side effective edge of each coil is Sm; in the same pole of the secondary winding, the number of the stator grooves in the same-side effective edge of each coil is ka; the sum of the wire-winding sectional areas of the same-side effective edge of each coil is Sa; and ka is greater than or equal to (Q-4) / 4 and less than or equal to km that is less than or equal to Q / 4, wherein Sm / Sa is greater than or equal to 1.05 and less than or equal to 1.50. According to the stator assemble provided by the embodiment of the invention, the magnetic flux harmonic of the winding can be lowered, the stray loss of the motor can be lowered, the area proportion of the secondary winding in the stator grooves can be increased, the heat dissipation loss of the main winding and the secondary winding is balanced, and the performance of the motor is improved.

The invention provides a method for lowering the stray loss of a motor, which relates to the technical field of the motor. The motor comprises a stator and a rotor, wherein the stator is in the shape of an annular column, and a plurality of stator winding holding tanks are axially and symmetrically arranged on the inner circumferential surface of the stator along the circumferential direction; and the rotor is in the shape of a circular column, and a plurality of rotor winding holding tanks are axially and symmetrically arranged on the outer circumferential surface of the rotor along the circumferential direction. The method is characterized in that the quantity of the rotor winding holding tanks is matched with the quantity of the stator winding holding tanks in a near-tank and few-tank mode which means that the quantity of the rotor winding holding tanks is less than the quantity of the stator winding holding tanks, and the difference between the quantity of the rotor winding holding tanks and the quantity of the stator winding holding tanks is less than or equal to 4. The method provided by the invention can improve the efficiency of the motor.

The invention discloses a high impedance shell type transformer. When the shell type transformer is a single-phase transformer, at least one magnetic flux leakage air channel gap iron core is arranged in a magnetic flux leakage air channel between a core column and a yoke of an iron core of the single-phase transformer. When the shell type transformer is a multi-phase transformer, at least one magnetic flux leakage air channel gap iron core is arranged in a magnetic flux leakage air channel between a core column and a yoke of an iron core of each phase in the single-phase transformer. Each magnetic flux leakage air channel gap iron core is composed of at least one magnetic conduction material and at least one gap base plate, the magnetic conduction materials and the gap base plates are arranged alternately, and the gap base plates are located between the magnetic conduction materials or between the magnetic conduction materials and the core columns or between the magnetic conduction materials and the yokes. Due to the fact that the magnetic flux leakage air channel gap iron cores composed of the magnetic conduction materials and the gap base plates are arranged in a magnetic flux leakage air channel of the shell type transformer, the high impedance shell type transformer achieves improvement of transformer impedance through increase of tiny materials.

The invention relates to a 330kV-level three-phase three-winding high-impedance power auto-transformer with the function of on-load voltage regulation and belongs to the technical field of transformers. According to the technical scheme, a low-voltage winding (3), a common winding (4), a series winding (5) and a regulating winding (6) are sequentially and concentrically sleeved outside a three-phase five-pole core (2), and the low-voltage winding is serially connected with an electric reactor. An on-load tap changer is disposed at the end of a transformer oil tank. The electric reactor serially connected with the low-voltage winding is in a three-phase three-pole structure. Rectangular magnetic shields formed by stacked steel strips are disposed at upper and lower ends of a reactor winding (7), and the reactor winding is compressed with tie bolts made of low magnetism steel. The reactor winding is integrally connected with a core of the transformer through a clamp. The 330kV-level three-phase three-winding high-impedance power auto-transformer with the function of on-load voltage regulation has the advantages that short-circuit impedance voltage between high and low tension windings as well as between medium and low tension windings are achieved in such manner that the low-voltage winding is serially connected with the electric reactor, the transformer is small in size, light in weight, low in loss and the like, stray loss is reduced, and local overheating is avoided.

The invention relates to a totally-enclosed self-ventilation traction motor for a low-floor vehicle. The motor comprises a base, a stator assembly, a rotor assembly, transmission end covers and non-transmission end covers which are respectevly installed at two sides of the base. Irregular counter bores and large air holes are formed in the outer edge of the periphery of a stator punching sheet inthe stator assembly. A stator pressing ring air channel communicating with the irregular counter bores and large air holes is formed in the position, close to the edge of the stator pressing ring, ofthe stator pressing ring, an air inlet communicating with the stator pressing ring air channel is formed in the non-transmission end covers, and an air outlet communicating with the irregular counterbores, large air holes and the stator pressing ring air channel is formed in the non-transmission end covers; an air outlet formed between the counter bores and the inner wall of the base, the large air holes and the stator pressing ring air channel commonly form an external circulating air path; small air holes located in the sealed space of the motor are arranged at the periphery of the stator punching sheet, an air gap is formed between the stator assembly and the rotor assembly, and an axial ventilation channel is arranged in the rotor; and the small air holes, the air gap and the rotor form two internal circulating air paths.

The invention discloses an IE5 three-phase asynchronous motor based on stator unequal-groove punching sheets and a cast-aluminum rotor. A rotor core of the motor is formed by laminating a plurality ofrotor punching sheets, each rotor punching sheet comprises an annular first substrate, a plurality of closed grooves are radially and uniformly formed in the outer annular surface of each first substrate along the circumferential direction of the first substrate, and aluminum conducting bars are cast in the closed grooves; a stator core of the motor is formed by laminating a plurality of stator unequal-groove punching sheets. Each stator unequal-slot punching sheet comprises a second substrate in a circular ring shape; stator groove groups used for placing copper wires are uniformly arrangedon the inner circular ring surface of the second substrate along the circumferential direction of the second substrate in a radial manner. The number of the stator slots of each pole and each phase ineach stator slot group is at least three, the stator slots comprise at least one large stator slot and at least two small stator slots, the large stator slot is arranged in the middle of the stator slot group, and the two sides of the large stator slot are respectively provided with one or more small stator slots; or at least one large stator slot, at least two middle stator slots and at least two small stator slots are included; the large stator slot is arranged in the middle of the stator slot group, two sides of the large stator slot are respectively provided with one or more small statorslots, one or more middle stator slots are respectively arranged between the large stator slot and the small stator slots, and concave slot wedges or convex slot wedges are plugged in the stator slotsembedded with the stator windings.

The invention discloses a motor rotor magnetic field sine method, a rotor structure, a motor and a compressor. According to the method, a plurality of magnetic line channels are arranged in the region between a permanent magnet of a motor rotor and the outer circle of an iron core, and the circumferential size of each magnetic force line channel is set, so that the magnetic fields of outer circles of the rotors of the magnetic force line channels can be distributed close to sine. The magnetic force line channels are arranged in the region between the outer circle of the iron core of a motor rotor and a permanent magnet, and the widths of the magnetic force line channels are set according to the sine function, so that the waveform of gap flux density inside the motor of the motor rotor structure can be optimized into a relatively ideal sine curve, and the gap flux density has less low-order harmonic quantity, so that stray loss, electromagnetic noise, vibration and other adverse influences caused by low-order harmonic quantity can be effectively reduced, and the comprehensive operation index of the motor can be promoted. Furthermore, the performance of a compressor and noise and vibration indexes can be improved.

The invention discloses a method for driving a high power high speed DC brushless motor controller. The method comprises the following steps of: driving a motor by adopting a pulse width modulation method, and sampling the position information of a motor rotor by adopting a Hall sensor in a pulse width modulation interval; detecting the regularity of the position information detected by the Hall sensor, detecting the rotating speed change rate of the motor, and ignoring a detection result if the position information of the Hall sensor is detected to exceed a set range; computing the rotating speed of a rotating model by utilizing periodic information obtained by the Hall sensor, and performing phase synchronization on the rotating model by utilizing separated position information obtainedby the Hall sensor to simulate the continuous position information of the motor. In the method, a sine wave driving scheme is adopted; the method has the advantages of low switching loss, low electromagnetic radiation, high efficiency, high bus voltage utilization rate and the like; and the rotating model has high stability, thereby achieving the high stability, low noise, low stray loss and highefficiency of the motor.

The invention belongs to the technical field of manufacturing of motors. In order to resolve the technical problem existing in the process of removing blanking stress of an iron core in the prior art, the invention provides a vibration aging processing device of a motor iron core. The vibration aging processing device of the motor iron core comprises a vibration platform, wherein rubber supporting legs are arranged under the vibration platform. The vibration aging processing device of the motor iron core is characterized in that an iron core pressing device is arranged in the middle of the vibration platform. The vibration aging processing device of the motor iron core further comprises a resonance vibration exciter, the resonance vibration exciter comprises a motor, an eccentric block is arranged on a motor shaft, the motor is clamped on an end portion of the vibration platform through a clamp, and the eccentric block can generate vibration impact on the vibration platform when the motor operates. The vibration aging processing device of the motor iron core further comprises a vibration aging instrument and an acceleration sensor, wherein the acceleration sensor is fixed to the surface of the iron core, and the acceleration sensor and the resonance vibration exciter are electrically connected with the vibration aging instrument. The motor iron core processed through the vibration aging processing device can improve the efficiency of the whole motor by 0.3-0.8%, the stray losses can be reduced by 15-25%, and the effect is obvious.

The invention discloses a flameproof three-phase asynchronous motor with high energy efficiency, the flameproof three-phase asynchronous motor includes a base, a stator mounted in the base and a rotormounted in cooperation with the stator, the rotor is fixedly mounted on a rotating shaft, the front and rear ends of the frame are respectively provided with end caps, bearings are arranged between the end caps and the rotating shaft, and the bearing inner cover and the bearing outer cover are respectively correspondingly arranged on the inner and outer sides of the bearing, and a connecting boxis also arranged at the outlet of the machine base, the bearing inner cover and the rotating shaft are closely matched to form an inner flameproof passage structure, the bearing outer cover and the rotating shaft are closely matched to form an outer flameproof passage structure, and the bearing outer cover is provided with an oil seal which is in an interference-fit relation with the rotating shaft; a spigot flameproof surface is formed at the matching part between the end cover and the machine base; the rotor is a cast aluminum rotor with a double squirrel cage structure, the surface of the rotor guide bar is provided with an insulating layer, and a gap is reserved between the rotor guide bar and the corresponding rotor groove. The flameproof three-phase asynchronous motor of the invention has reasonable structure, safety and reliability, and is convenient for users to use.

The invention provides a transformer capable of increasing impedance. The transformer comprises a main transformer part, an in-series transformer part, a switch and an electric reactor, wherein the electric reactor and the switch are taken as an impedance regulator; when the transformer needs the small impedance, the switch is flipped down, and the electric reactor is disconnected; when the transformer needs the large impedance, the switch is flipped up, the electric reactor is in an in-series connection with the transformer, and the impedance of the transformer increases; and if the electric reactor is controllable, the impedance of the transformer can be adjusted at will. The design will become a revolutionary change in high-voltage and ultra-high voltage power transmission systems. The transformer has the advantages that system safety is greatly enhanced, and system cost is reduced; and current limiting, current stabilization, filtering, damping and the like of the system will become controllable. The transformer can be applied to high-voltage, extra high-voltage and ultrahigh-voltage AC and DC power transmission as well as other electric power systems in need of the current limiting, current stabilization, filtering and damping.

The invention discloses a clamping device of a three-dimensional wound core transformer and a transformer. The clamping device comprises a lower frame, a plurality of upper pressing plate assemblies and a plurality of screw assemblies, the lower frame is arranged on the lower sides of a plurality of coil windings of the three-dimensional wound core transformer, the upper pressing plate assemblies are distributed on the upper sides of the coil windings, the lower frame and the upper pressing plate assemblies are connected through the screw assemblies so as to jointly clamp the coil windings. The transformer provided by the embodiment of the invention, the clamping device is adopted; compared with a traditional clamping device, the clamping device of the invention can assist in reducing steel consumables at the periphery of the iron core, is simpler in structure, occupies a smaller space, is lighter in weight and saves materials and reduces stray loss of the transformer.

The invention relates to the field of power transformers, in particular to a transformer iron core structure and a power transformer. The transformer iron core structure comprises a shell, a bottom plate cavity, a slotted support frame, a transformation component and the like; and a bottom plate cavity is fixedly installed in the shell, a slotting supporting frame is fixedly installed on the bottom plate cavity, and the voltage transformation component is arranged on the slotting supporting frame. By arranging the silicon steel binding posts, the silicon steel binding posts utilize orientation of silicon steel sheets and an annealing process, additional loss can be reduced, current transmission efficiency can be improved, the silicon steel iron chips are made of high-permeability silicon steel sheets, loss is fully reduced, meanwhile, the silicon steel iron chips are stacked in a stepped mode, iron loss can be reduced by about 8%, and the purpose of effectively reducing loss is achieved.

The invention relates to a local component of a transformer, in particular to a high-capacity transformer magnetic shielding device. The high-capacity transformer magnetic shielding device comprises an iron yoke and a clamping piece which are arranged on the transformer, and is characterized in that a magnetic shielding block matched with the iron yoke is arranged on the clamping piece, the magnetic shielding block is formed by superposing a plurality of layers of silicon steel sheets, and a frame is fixed on the outer sides of the silicon steel sheets. The high-capacity transformer magnetic shielding device has the advantages that leakage flux is prevented from passing through the structural part to be closed, the purposes of reducing stray loss and solving the problem of local overheating of the structural part are achieved, the structure is simple, the shielding effect is good, and the manufacturing and using cost of the transformer is greatly reduced.

The invention discloses a motor rotor magnetic field sine method, a rotor structure, a motor and a compressor. According to the method, a plurality of magnetic line channels are arranged in the region between a permanent magnet of a motor rotor and the outer circle of an iron core, and the circumferential size of each magnetic force line channel is set, so that the magnetic fields of outer circles of the rotors of the magnetic force line channels can be distributed close to sine. The magnetic force line channels are arranged in the region between the outer circle of the iron core of a motor rotor and a permanent magnet, and the widths of the magnetic force line channels are set according to the sine function, so that the waveform of gap flux density inside the motor of the motor rotor structure can be optimized into a relatively ideal sine curve, and the gap flux density has less low-order harmonic quantity, so that stray loss, electromagnetic noise, vibration and other adverse influences caused by low-order harmonic quantity can be effectively reduced, and the comprehensive operation index of the motor can be promoted. Furthermore, the performance of a compressor and noise and vibration indexes can be improved.

The invention provides a ZPSC-type phase shift rectifier transformer which comprises a transformer base, an upper clamp part, a lower clamp part, supporting strip, a cooling air channel, a cooling fan and a winding. The winding comprises an iron core, a low-voltage coil including a main winding and a phase shift winding, an epoxy resin cylinder and a high-voltage coil, the low-voltage coil, the epoxy resin cylinder and the high-voltage coil are sequentially arranged on the outer side of the iron core, the low-voltage coil and the high-voltage coil can be wound according to relevant required sizes during winding, and both the upper clamp part and the lower clamp part are provided with reinforcing plates. The ZPSC-type phase shift rectifier transformer is characterized by also comprising a low-voltage coil outgoing head, wherein the low-voltage coil outgoing head is an 8-shaped woven outgoing head, and the low-voltage coil is arranged in the low-voltage coil outgoing head. The ZPSC-type phase shift rectifier transformer is convenient to use and easy to process, has the advantages of being low in temperature rise, low in partial discharge level, low in loss, strong in overload capacity and the like and can be manufactured in a unique structural form according to the transformer size demand of a customer.

The invention discloses a stator for efficient and super-efficient three-phase asynchronous motors, which comprises a plurality of stator core sheets and two pressing sheets positioned at the end parts of the stator core sheets, wherein a plurality of W-shaped notches are arranged on the excircle circumferences of the stator core sheets and the pressing sheets at intervals, meanwhile, the stator formed by the overlapping of the stator core sheets and the two pressing sheets is provided with an axial W-shaped welding groove formed by the overlapping of the W-shaped notches on the excircle circumferences, the stator core sheets and the two pressing sheets are fixed in the W-shaped welding groove in a welding manner to ensure that the production efficiency of the stator is greatly improved, the materials used in a stator core manufacturing process are reduced, and the cost is lowered, and ensure that the mechanical strength of a stator core and the accuracy of the verticality can be improved, the lamination coefficient of the stator core sheets is increased, the stray loss, the core loss and the eddy-current loss are decreased, thus the output efficiency of a motor is improved.

The invention provides a rotor, a motor, a compressor, an air conditioner and a vehicle. The rotor comprises: a rotor iron core, wherein a plurality of magnet grooves are formed in the rotor iron core, and the magnet grooves are located in the peripheral side of the rotor iron core; and permanent magnets arranged in the magnet grooves, wherein the cross section contour line of the permanent magneton the side opposite to the magnet grooves comprises at least one section of straight line. The motor maximally increases the use number of the permanent magnets, and reduces the copper loss, so themotor efficiency is increased; and in addition, the thicknesses of the permanent magnets of the rotor are not uniform, so that the torque ripple of the motor is small, the air gap flux density harmonic content is reduced, the motor efficiency is further improved, and the miniaturization of the motor is realized.

There are many varieties of windings. Coils adopting an edgewise winding wire in which winding wires are wound around in the radial direction of the coil have a wide flux linkage area orthogonal to the electric wire, so that stray loss within the wire is increased, winding wire loss is increased and temperature is raised thereby. The present invention provides an arrangement in which a plurality of coil units are prepared and connected via external coupling terminals. At this time, winding is performed so that the contact faces of the coil units have equal potentials, so that there is no need to ensure an insulation distance between coils, and the coils can be downsized. Therefore, the mass of the respective coils can be reduced. Taps disposed on the respective coils are arranged to have equal potentials, according to which the external coupling terminals can double as tap switch terminals, so that there is no need to provide a dedicated tap switch.

The invention relates to a three-phase asynchronous motor skewed-slot rotor structure which comprises a rotor body, and is characterized in that a plurality of rotor skewed slots are formed in the rotor body; the value b, namely a skewed stator tooth pitch, of each rotor skewed slot is 26.7 mm; the outer diameter of the rotor body is 356.8 mm; the length of the rotor core is 560 mm. According to the invention, the rotor skewed slots are adopted, the starting performance of the motor can be effectively improved, and the electromagnetic noise is reduced, the noise value before improvement is 86 dB, and the noise value after improvement is 81 dB; the mechanical loss and stray loss of the motor are further reduced, noise pollution of the environment cannot be produced, and the three-phase asynchronous motor skewed-slot rotor structure can be widely applied to rotor cores of high-voltage and efficient Y2-HV 315X-4-355KW 6KV motors.

The invention discloses an asynchronous motor winding with five-phase power sources, and belongs to the technical field of motors. The asynchronous motor winding is characterized in that the asynchronous motor winding is provided with 40 stator slots and 40 poles, is a single-layer winding and is totally provided with 10 branch circuits A1, A2, B1, B2, C1, C2, D1, D2, E1 and E2 as seen from the inside of a motor, each branch circuit comprises two coils, and each coil has integral pitch; one end of the branch circuit A1, one end of the branch circuit B1, one end of the branch circuit C1, one end of the branch circuit D1 and one end of the branch circuit E1 are connected with one another to form a common point O and are not led out; the other end of the branch circuit A1, the other end of the branch circuit B1, the other end of the branch circuit C1, the other end of the branch circuit D1 and the other end of the branch circuit E1 are outwardly led out, are denoted as A, B, C, D and E and have mutual difference of 72 electric degrees. The asynchronous motor winding has the advantages that the asynchronous motor winding is a twenty-phase system as seen from the inside of the motor andis a five-phase system as seen fro the outside of the motor, harmonic components can be reduced to a great extent by the asynchronous motor winding with the connection, accordingly, noise can be lowered, vibration, stray loss and harmonic torque can be reduced, and effective materials can be saved; the asynchronous motor winding has practical engineering application significance, tertiary harmonic currents can be injected into the motor while the motor is filled with fundamental currents, the ferromagnetism saturation of the motor can be reduced after the tertiary harmonic currents are injected into the motor, and the ferromagnetic material utilization rate and the torque density of the motor can be increased.

The invention discloses a multi-phase electric motor equipped with a polygonal winding, and belongs to the technical filed of a motor. The winding is designed, and when the power supply phase number mis an odd number and when a 180-degree / m phase band is adopted, the magnetic potential space harmonic number of times is v which is equal to 4km+1, wherein k is a positive or negative integer comprising zero; for example, when m is equal to 3, and when the 180-degree / m phase band is adopted, v is equal to 1, -11, +13, -23, +25 and so on based on the same rule, and a 12-phaes winding is formed equivalently; and when m is equal to 5, and when the 180-degree / m phase band is adopted, v is equal to 1, -19, +21, -39, +41 and so on based on the same rule, and a 20-phaes winding is formed equivalently. Seem from the interior of the motor, a 4m-phase system is formed while seem from the exterior of the motor, an m-phase system is formed; by virtue of the winding in the connection method, the harmonic ingredients can be greatly lowered, and vibration, noise, harmonic torque and stray loss can be reduced while effective material can be saved, an actual engineering application value can be achieved; when the electric motor in the winding connection method is pumped with a fundamental current, a harmonic current also can be injected at the same time; and after the harmonic current is injected, the ferromagnetic saturability of the electric motor can be reduced while the torque density of the electric motor is also improved.

The invention discloses a non-woven reinforcement magnetic slot wedge. A sheet magnetic conductive unit can lower the eddy current loss of itself, the distribution of magnetic lines of force in a stator groove can be changed, so that the intensity of harmonic waves is lowered, the effect of lowering the loss of the harmonic waves is achieved, a non-woven reinforcement structure can meet a requirement for structural rigidity and intensity and a requirement for turbonator air gap electromagnetic force, and the purposes of lowering the stray loss and improving the efficiency of the turnonator, increasing the performance index of the tunonator, and improving the reliability are achieved.

The invention relates to a transformer and a power generation system. The transformer comprises an iron core, a first coil, a second coil and a lead, wherein the first coil and the second coil are wound on the iron core; the first coil comprises a first terminal and a second terminal, the lead comprises a first line segment, a second line segment and a third line segment, a first end of the firstline segment is connected with the first terminal, a second end of the first line segment is connected with a first end of the third line segment through the second line segment, and a second end of the third line segment is connected with the second terminal; the winding direction of the first coil on the longitudinal section of the iron core is taken as a positive direction, wherein the windingdirection takes the first wiring end as a starting point; and the first line segment is located on the opposite side of the third line segment. The first line segment of the lead is located on the opposite side of the third line segment, so that the current direction of the lead is changed, the magnetic field direction generated by the current of the lead and the leakage magnetic field direction generated by the current of the first coil are opposite, a space magnetic field is restrained, stray losses are reduced, and local overheating of a clamping piece can be avoided.

The invention relates to a single-phase self-starting permanent magnet synchronous motor, which belongs to the field of micromotors, is used as a driving motor of a mini-type water pump, a cooling system of a vehicle engine and a driving motor of a warm air system circulating pump, and can also be used in other aspects. The invention aims to improve the starting performance and the operational performance, and is characterized in that the single-phase self-starting permanent magnet synchronous motor is provided with two protruding stator magnetic poles, the pole arc of the magnetic pole at each side consists of four sections, wherein the first section has the maximum length and minimum air gap length, the second section has the maximum air gap length and is at the point of a pole shoe centerline, the air gap length of the third section is gradually reduced, the length of the fourth section is smaller than or equal to 1 / 2 of that of the first section, and the air gap length of the fourth section is minimum.

A mild harmonic energy-saving transformer is provided, which relates to a power transformer based on the phase shift principle and adapted to inhibit harmonic waves and reduce energy consumption. The primary winding of the transformer is adapted to the D connection and the secondary winding is adapted to the Z connection with double outputs, that is, the secondary winding is divided into a first group of winding (A1) and a second group of winding (A2). The first group of winding (A1) comprises a first phase winding (a1), a second phase winding (b1) and a third phase winding (c1). The second group of winding (A2) comprises a fourth phase winding (a2), a fifth phase winding (b2) and a sixth phase winding (c2). The mild harmonic energy-saving transformer can inhibit the third harmonic and eliminate the fifth, seventh, seventeenth and nineteenth times harmonics; weaken the harmonic current and the harmonic current-induced coupled magnetic flux of the first and the secondary windings and the current circulation of the first side winding; reduce the stray loss of the transformer; and significantly improve the influence of the secondary harmonic on the primary power network.

The present invention relates to the field of power transformers, in particular to a transformer core structure and a power transformer, including a casing, a bottom plate cavity, a slotted support frame, a transformer component, etc.; the bottom plate cavity is fixedly installed in the casing, and the A slotted support frame is fixedly installed on the bottom plate chamber, and the pressure transformation component is arranged on the slotted support frame. Through the silicon steel terminal, the silicon steel terminal utilizes the orientation of the silicon steel sheet and adopts the annealing process, which can reduce additional loss and increase the current transmission efficiency. The silicon steel chip uses a high magnetic permeability silicon steel sheet to fully reduce the loss. Stacking can reduce iron loss by about 8%, achieving the purpose of effectively reducing loss.