Asynchronous double-speed motor
SUBSTANCE: motor consists of body with stator with low and high speed windings mounted in slots, rotor fixed at motor shaft and box of inputs with through joints connected to outputs of specified windings. According to invention winding changeover device is located at motor body; input terminals of the motor should have facilities for connection of feeder current-carrying leads and output terminals of winding changeover device should be connected electrically with through joints connected to outputs of motor windings. Winding changeover device can be located in box of inputs; for this purpose two outputs of this device should be connected through its break-type contacts to outputs of low speed windings of the motor and two outputs through normally open contacts of device should be connected to through joints, which are connected to high speed windings of the motor. Third outputs of low and high speed windings should be interconnected and then connected to the third through joint in box of motor inputs.
EFFECT: simplification of power supply system structure, improvement of control and protection, enhancement of reliability and operation of asynchronous double-speed motors due to their power supply by one cable and due to motor control and protection by one device instead of two devices.
2 cl, 2 dwg
The invention relates to electrical engineering, in particular to asynchronous two-speed motors.
Known induction motor, which consists of a casing in which is mounted a stator winding, a rotor mounted on the shaft, and a box of inputs intended for insertion of the cable which is supplied the power supply to the electric motor. In the specified box placed 3 bushing clamp connected with the conclusions of the stator winding, which are attached to conductor wires of the power cable .
These motors exhibit this drawback, as the impossibility of changing the speed of rotation of the shaft without changing the frequency of the supply voltage that does not allow you to adjust the speed of the mechanism, which is provided, for example a pipeline, and leads to the increased cost of electricity when the engine is not loaded and does not need all the power of the motor.
Also known two-speed motors, which coincide with the proposed invention for most of the main signs and consist of a housing in which is mounted a stator with windings low and high speed, the rotor is placed on the shaft, and a box of inputs with two cable glands and bushing clamps, each of which is connected with the corresponding output windings of both low and high speeds .
This is lektrodvigatelem a number of inherent disadvantages, such as complexity, lack of reliability and system security management and protection, as well as themselves motors. This is because the power of such motors have two cables connected respectively to the windings of the low and high speed, as well as two machine control and protection. In this variation of the characteristics of control devices, in particular, their performance leads to the inclusion of the windings high speed, or when another ragged low speed windings, or to their integration with considerable interval of time after turning off the specified low speed windings. The electric motor and the transmission mechanism, which is given them in the motion, are subjected to significant mechanical and electric shock overload, which leads to a decrease in their reliability. In addition, putting considerable stress on the disabled winding low or high speed and the lack of security features on this accession leads to increased danger of destruction of people by electric current, and in mines with a potentially explosive atmosphere to the possibility of an explosion.
The objective of the proposed invention is to simplify the design of the motor and power system, control and protection, improving the reliability and security of the and operation of two-speed asynchronous motors.
For this purpose, in known two-speed asynchronous electric motor, which consists of a housing, a stator mounted with its grooves windings low and high speed, fixed in the specified casing, a rotor mounted on the motor shaft, and a box of inputs with loop-through terminals connected to the winding findings suggested on the motor housing to position the switching device of windings, cable clamps which attach the wires of the power cable and lead it clamps to connect with these bushing clamps. The design of the proposed motor is also distinguished by the fact that said switching device is mounted in its introductory box, two output which is connected to its normally open contacts connected to the through terminals connected to the winding outputs a low speed, and two outputs connected contact closure device, is connected with the bushing clamps, which are connected with two terminals of the windings high speed, and the third winding findings low and high speed connected with each other and with lock clip is attached to one current-carrying lived power cable, and a switching device designed in a way that is not normal sparking parts. To do this, the power circuit device is performed on vacuum arcs is tted with cameras, the control wires of the power cable directly connected to the coil of the electromagnetic drive device switch.
Listed above are the essential features of the invention, differing from the prototype, the necessary and sufficient in all cases covered by the scope of legal protection of inventions.
Mount the motor housing of the device switching windings enables to realize the power of this motor over a single cable from one device control and protection instead of two and to exclude the supply voltage is disconnected from the power source cable and conclusions off of device management and security, because they are missing.
This greatly simplifies the power supply system, control and protection of the proposed motor and increases the safety of its operation.
To significantly simplify the design of the proposed motor leads floatation device switching windings in his introductory box with the ability to connect two lived power cable directly to the input terminals of the specified device and connecting the terminals of one phase winding low speed and high speed with each other and with common lock clip. For electric motors, which operate in an explosive atmosphere, building products, to the which are normally sparking parts, in the introductory box is prohibited. The proposed embodiment of a device switching the windings can be placed in the introductory box motor without limitation the conditions of its use.
The proposed invention is explained by the drawings, there is shown a two-speed motor with integrated switching device of the windings:
- figure 1 is a side view;
- figure 2 - rear view.
Asynchronous two-speed electric motor consists of a housing 1, a stator 2 with mounted in the grooves of the windings of the low and high speed, fixed in the housing 1, a rotor 3 mounted on the shaft 4, the terminal box 5 with bushing clamps 6, 7 and 8, the device switching windings 9 introductory clips 10 and the lead terminals 11. Box inputs has a cable inlet 12, through which the supply cable 13 is introduced in the introductory box 5.
Asynchronous two-speed motor runs thus.
When voltage is applied to conductor wires of the power cable 13 voltage through the introductory clips 10 and included contacts switching windings 9 is fed through the bushing clamps 6 two-phase winding outputs a low speed motor. The voltage of one phase is served by cable 13 directly at the entrance of the clamp 8, which is connected with the conclusions of the windings of the low and high speed. Consequently the those on the low speed winding is energized and the motor turns on at low speed.
To switch the motor at a high speed from the management apparatus serves the voltage on the coil of an electromagnet drive device switching windings. This device is activated, disables the low speed winding and includes winding a high speed, because it relieves tension with walk-through terminals 6 and delivers it to the bushing clamps 7. Thus, the rotor 4 of the electric motor starts to rotate at high speed.
To move the motor in the low speed mode, you need to remove the voltage from the windings of the electromagnet device switching windings 9 and turn it off.
The combination of on and off of the motor windings in one switching device - device switching windings allows you to almost instantly perform switching of the motor windings while guaranteeing the impossibility of motor operation when the windings of both low and high speed. This dramatically increases the reliability of the motor and mechanism, which provides them in action.
Sources of information
1. USSR author's certificate No. 633115, H02K 9/22. Electric machine. Bull. No. 42, 1978.
2. The catalogue of production of JSC "Donetsk electrotechnical plant". Motors explosion-proof series ADVC 315 M12/4, ADC 355 LA 8/4.
1. Asynchronous is wojskowej motor, which consists of a housing, a stator mounted with its grooves windings low and high speed, fixed in the specified case, the rotor attached to the shaft of the motor and box inputs with loop-through terminals connected with the conclusions of these windings, characterized in that on the specified motor housing set the switching device to its windings, input terminals of which are equipped with devices for the connection of current-carrying conductors of the supplying cable and pin clamps the specified device switching windings electrically connected with the bushing clamps that are attached to the leads of the windings of the motor.
2. Asynchronous two-speed electric motor according to claim 1, characterized in that the switching device of the windings placed in a box inputs, two outputs of this device through its normally closed contacts connected with the conclusions of the low speed winding of the motor, and two output trailing through his contacts connected to the through terminals connected to the winding outputs high speed motor, and a third winding findings of high and low speed are interconnected and attached to the pipe clamp in box inputs of the motor.
FIELD: electric engineering.
SUBSTANCE: proposed partially enclosed asynchronous motor comprises rotor assembly, stator assembly and metal frame shaping the body having cylindrical shape in general, with bearing bodies at each axial end. Inner part of frame is arranged with the possibility to tightly embrace plate core and follows contour of stator assembly winding front parts bends. Body seal between stator assembly and rotor assembly tightly seals rotor assembly relative to stator assembly. Heat conducting shaping material fills gaps in winding of stator and space between assembly of stator and frame. Fan driven by rotor shaft and jacket of fan send air along body seal and through assembly of rotor.
EFFECT: improved dimensional parametres and increased reliability of semienclosed asynchronous motor.
8 cl, 15 dwg
FIELD: electric engineering and electro-mechanical industry, in particular, cooling of electric machines with gas cooling with axial cooling of rotor and tangential cooling of stator.
SUBSTANCE: stator of electric machine with gas cooling contains core with tooth zone and yoke zone, with radial ventilation channel, and also cover and longitudinal walls, mounted between core and cover with forming of alternating zones of high and low pressure, in accordance to current invention, core is provided with thermal elements, mounted in tooth zone of ventilation channels with partial protrusion into yoke zone of stator core.
EFFECT: improved cooling of electric machines with small value of air gap by increasing cooling efficiency of tooth zone of electric machine stator core.
2 cl, 4 dwg
FIELD: electric engineering, electro-mechanical industry, possible use for manufacturing explosion-proof electric machines.
SUBSTANCE: in the method, including pressurization of current-conductive elements outputs electric machine by means of explosion-proof cover, internal space is proposed in accordance to invention, limited by explosion-proof cover, to be subjected simultaneously to cooling, drying and dust-cleaning, while dust-cleaning is performed in places of immediate dust forming, using sticky materials as dust catchers, for example, sticky substances on basis of organic components. Also proposed is an electric machine, containing explosion-proof cover, positioned inside of which are stator, anchor, collector, coal brushes, wherein it is proposed to additionally include heat exchanger made in form of pipe, ribbed with heat-sinking plates, moisture absorber, made in form of stocking of perforated material, internal hollow of which is filled with moisture absorber, while on external surface rings are held, made of dense material, dust catcher, made in form of a layer of sticky material, applied to internal surface of explosion-proof cover, and also to surfaces of heat-sinking plates of heat exchanger and rings of moisture absorber.
EFFECT: increased operational reliability of electric machine.
2 cl, 3 dwg
SUBSTANCE: rotor of an asynchronous electric machine comprises a shaft, a ferromagnetic core fixed coaxially on the shaft - a magnetic conductor with an external surface in the form of a circular cylinder and an electric winding of "squirrel cage" type. At the same time according to this invention, the ferromagnetic core - magnetic conductor consists of longitudinal elements made of material having at least axial electroconductivity, besides, the longitudinal elements with the help of frontal conductors - links are electrically connected to each other only by their end parts, forming a winding of "squirrel cage" type.
EFFECT: considerable improvement of weight and dimension characteristics of an electric machine, reduced prime cost of its manufacturing, considerable reduction of teeth pulsations of the torque on the shaft of the asynchronous electric machine with a rotor made according to this invention.
10 cl, 2 dwg
FIELD: engines and pumps.
SUBSTANCE: in asynchronous motor the following is used: semi-open (up to 2.2 mm) rotor slots of special design without chamfer with transition at the height of 1 mm to wide part of the slot top; stator slots having upper part of arched design and maximum opening up to 4 mm on condition that number of pairs of poles 2p = 6 - 12 is chosen so that frequency of supply voltage is not lower than 4 Hz, with rigid matching of ratio of numbers of rotor slots of 66-130 and stator slots of 54 - 108 at the number of rotor slots more than number of stator slots by 20%; stator winding with number of slots per pole and phase is at least 2; magnetic system made from steel having high values of induction without connection to value of specific losses.
EFFECT: higher energy data and overload capacity of electric motor, including at its operation in generator mode.
2 dwg, 1 tbl
SUBSTANCE: low-speed asynchronous electric motor includes stator with multi-phase winding and rotor with interleaved core and short-circuited winding. Stator phases are made in the form of annular windings coaxial with rotor, each of which is located between two annular magnetic cores with teeth protruding in axial direction and which are opposite directed. At that, annular magnetic cores of the phase are offset relative to each other through π/z angle, and between them there arranged is toroidal magnetic core, and annular magnetic core of various phases are offset relative to each other through 2π/z·m angle, where z - the number of teeth of each annular magnetic core, and m - the number of phases.
EFFECT: simplifying the manufacturing procedure of the stator windings at simultaneous technically possible increase of the number of poles of low-speed asynchronous electric motor.
SUBSTANCE: in the proposed electric motor containing stator (2) with single-phase winding (6) and rotor (13) with squirrel cage (24), stator (2) has magnetic core (3) and magnetic core (4), the symmetry axes of which are parallel to each other and perpendicular to rotor (13) rotation axis; poles (5) of magnetic core (3) lie in its symmetry axis, magnetic core (4) is ring-shaped and has one pair of poles (11) on inner side of the ring; angle between symmetry axis of each pole (11) and symmetry axis of magnetic core (4) lies within 15° to 75°; on poles (11) there arranged is winding (12) in the form of coil wound on spiral; on the part of magnetic core (4), which is opposite to poles (11), there is winding (9) representing the coil wound on spiral; windings (9) and (12) are connected to each other so that the direction of their coiling is the same; rotor (13) is located between poles (5) and (11).
EFFECT: simplifying the design, improving operating reliability of electric motor, and reducing its operating costs.
2 cl, 3 dwg
SUBSTANCE: asynchronous motor with hollow short-circuit rotor includes hollow rotor and external stator with core and winding, as well as additional rotor installed on the shaft in the zone restricted with stator with possibility of rotation irrespective of hollow rotor, made from ring-shaped magnet radially magnetised with the number of pairs of poles, which is equal to the number of pairs of poles of stator winding, on which there pressed is thin-wall sleeve from conducting material, and hollow rotor is made in the form of thin-wall shell from conducting material.
EFFECT: increasing power coefficient and efficiency of asynchronous motor with hollow rotor without deterioration of its dynamic characteristics.
3 cl, 2 dwg
SUBSTANCE: there is proposed rotor of asynchronous motor which includes magnetic conductor fixed on shaft and in slots of which there arranged is short-circuited winding made from cast metal. Cast metal of winding contains 98.80 - 99.95% of copper, as well as alloying elements and impurities in the form of plumbum, stannum, bismuth, antimony, nickel, zinc, cadmium, phosphorus and arsenic. In addition, lithium is added to cast metal of short-circuited winding.
EFFECT: increasing density, decreasing the influence of impurities and increasing conductivity of cast metal of short-circuited winding of rotor of asynchronous motor.
SUBSTANCE: additional effect of rotating electromagnetic stator field on sectors of short-circuit rotor winding coils passing through areas adjoining stator pole half-pitch borders is added to effect of rotating electromagnetic stator field on short-circuit rotor winding coils passing through areas adjoining stator pole pith borders. Machine retains field rotation effect and continues full-scale operation with one phase disconnected, generating high-quality harmonic voltage of missing phase in disconnected phase winding.
EFFECT: starting current ratio reduced by motor due to prevention of braking losses, increased number of starts without load loss, possible application of the machine in most difficult operation environment with high shaft load.
6 cl, 4 dwg
FIELD: electric engineering.
SUBSTANCE: proposed short-circuited rotor with squirrel cage comprises shaft (1) and laminated core of sheet steel (2), in laminated core of sheet steel (2) there are rotor winding (3) rods located, which at both ends of laminated core of sheet steel (2) are pulled through openings (10) of each end plate (9) and closed by short-circuited ring (4), which, being electrically conducting, connects ends of rotor winding (3) rods on one side of short-circuited rotor to squirrel cage, besides each end plate (9) comprises circumferential ledge, which at least partially covers short-circuiting ring (4) with geometric closure at its outer side, besides each end plate (9) comprises part of rotor winding (3) rod and part of short-circuiting ring (4). At the same time, according to the present invention, end plates (9) are arranged as massive and are made of stronger material compared to rods of rotor winding (3) and short-circuiting rings (4), besides rods of rotor winding (3) have bulge at their ends with increased cross section of rod (7), moreover, at least part of rotor winding (3) rods bulge lies in openings (10) of end plates (9), besides transition between bulge and short-circuiting ring (4) is arranged in the form of rounding with transitional radius (8).
EFFECT: improved reliability of short-circuited rotor and asynchronous machine as a whole by elimination of possibility of breakage in transitional area of rotor winding rods and short-circuiting rings, provision of reliable retention of short-circuiting rings at high speeds of rotation and centrifugal forces.
9 cl, 13 dwg
SUBSTANCE: invention relates to electrical engineering and may be used in other engineering branches, for example wind-power engineering. The main point of the invention is the use of specific common rotor in asynchronous machine with two stators and common rotor. The above-mentioned common rotor rotates freely with regard to the shaft and at the same time has two separate short-circuited windings for each stator and one common short-circuited winding for both stators. One stator is fixed to the shaft, while the other rotates together with it. The windings of the fixed stator and the stator rotating together with shaft are made up from windings of two or more unequal sections of the above stators. In addition, the minor sector of the fixed stator winding and the minor winding sector of the stator rotating together with the shaft are connected to the mains. The same connection is ensured for large sectors or next by the size sections of the fixed stator or stator rotating together with stator shaft.
EFFECT: increase of electromagnetic moment at smaller dimensions, while ensuring moment control.
FIELD: electric engineering, possible use for engineering asynchronous electric machines with short-circuited rotor.
SUBSTANCE: the rotor includes magnetic conductor with a yoke, a short-circuited winding, ventilation blades, short-circuiting ring, rods, ribs and stator. In accordance to the invention, ventilation blades are made current-conductive in form of several current-conductive, vertically mounted rods, connected to one short-circuiting ring of magnetic conductor, while upper part of current conductive ventilation blades is wedge-shaped, narrowing towards the working air gap and having cross-section area which is equal to or greater than the area of cross-section of current-conductive rod of magnetic conductor. Ventilating current-conductive blades may be installed according to two variants: in the first variant - vertically along internal and external diameters of short-circuiting ring of magnetic conductor, and in the second variant - vertically only along the internal diameter of short-circuiting ring of magnetic conductor, or only along external diameter of short-circuiting ring of magnetic conductor with possible passage of electric current through vertically mounted current-conductive rods of aforementioned blades along their whole height. The short-circuiting ring is installed on the side which is opposite to working air gap and positioned along the internal diameter of magnetic conductor, and ribs of ventilating current-conductive blades are installed on one short-circuiting ring.
EFFECT: reduced metal consumption and increased operational reliability of rotor.
3 cl, 3 dwg
FIELD: electrical and electromechanical engineering; face-type induction machines having one stator and one rotor.
SUBSTANCE: proposed machine has stator ring-type magnetic cores carrying field winding, as well as squirrel-cage rotor, stator base endshield accommodating supporting sleeve, rotor disk, bearing assembly incorporating rotor shaft bearings, and thrust bearing. Stator base endshield is fixed in position by means of enclosing hollow cylinder with thrust bearing disposed on its inner surface and tightly fitted on one end to annular boss of hollow cylinder and on other end abuts against rotor disk. Up to three actuating mechanisms can be coupled with this machine.
EFFECT: enhanced diametric dimensions of stator and rotor cores, minimized air gap between them, enhanced loading capacity and operating reliability of machine.
1 cl, 1 dwg
FIELD: electromechanical engineering; squirrel-cage rotors of induction motors.
SUBSTANCE: proposed squirrel-cage rotor has laminated ferromagnetic core accommodating squirrel-cage winding bars. Upper part of bar has single- or double-ended longitudinal rectangular-section lateral slots which are not filled with ferromagnetic material. Double-ended longitudinal slots provided in upper part of bar are alternately disposed on one and other sides of bar.
EFFECT: enhanced starting torque of motor without changing starting current.
4 cl, 6 dwg