193 results about "Squirrel-cage rotor" patented technology

Ceramic adhesive is applied inside the slots of an electric machine squirrel cage rotor prior to casting or insertion of rotor conductors. This heat-resistant insulation provides superior electrical insulation that is also mechanically rugged, thus enabling casting of squirrel cage rotors by die or cost-effective consumable pattern casting. The consumable pattern cast copper rotors are electrically well insulated, thus minimizing rotor losses. The ceramic insulation in cast rotors enables longer conductors to be cast by thermally insulating the molten metal from the cooler laminations. The ceramic insulation in fabricated rotors withstands the high temperatures of end ring attachment. This method is applicable to both conventional induction machine rotors and brushless doubly-fed induction machine rotors and provides the degree of electrical isolation of the bars from the laminations needed to avoid excessive parasitic torques in doubly-fed machines, while ensuring adequate thermal conductivity to dissipate conductive bar heat to the laminations.

The invention relates to a casting method and casting machine of the induction motor cooper squirrel-cage rotor, which is suitable for the casting of pure copper and high copper content alloy. The invention belongs to nonferrous metal smelting and rolling process technology filed. The casting method comprises module pre-process, copper smelting, liquid casting and forming and quench water cooling. The casting method adopts a casting device which is composed of a casting machine and a smelting furnace, wherein, the smelting furnace comprises an integrated pot and middle frequency induction furnace, the heating efficiency of the middle frequency induction furnace is 0 to 100KW; the casting module comprises a group connection which is connected by a plurality of embedded lump. The invention has reasonable technics and equipment, the product has no defects of breakage on casting piece and surface, poor filling and mold sticking, the shaking present value complies with the R degree provision in IEC34-14(1994), which has the advantages of improving by one degree comparing with the N degree stipulated in Y series motor technology condition.

There is provided an induction machine having a squirrel-cage rotor, the rotor including: a rotor core; a plurality of rotor slots formed on the rotor core and aligned circumferentially at a predetermined interval; a plurality of rotor bars inserted into one of the plurality of rotor slots; and a plurality of rotor slits formed adjacent to the plurality of rotor slots on an outer circumferential side of the rotor core. The each rotor slit is formed as a hollow such that a cross sectional shape thereof is distinguished into three parts of a slit outer circumferential part, a slit intermediate part, and a slit inner circumferential part. A circumferential width of the each rotor slit on an innermost circumferential side is larger than that on an outermost circumferential side. A circumferential width of the slit intermediate part increases from an outer circumferential side toward an inner circumferential side.

A system including an induction machine with a toroidally wound stator and a squirrel cage rotor is presented. The toroidally wound stator has a plurality of phase windings. A position sensor may be operatively connected to the induction machine for providing a position indication that is indicative of a relative position of the rotor and the stator. The system also includes an inverter having a plurality of solid-state switches and a control system. The inverter has the same number of phases as the toroidal induction machine. The inverter is connected to selectively energize the phase windings. A programmable microprocessor, such as a digital signal processor, is operatively connected to the induction machine and includes a program to implement vector control of the induction machine. The microprocessor can also control the inverter so that the induction machine operates with a predetermined number of poles using pole phase modulation.

A rotor for an induction motor and a method of preparing same. The method includes making a squirrel-cage rotor made up of a cage and a laminate stack by forming a mold around the stack, heating the stack and introducing a molten metal into the mold such that the molten metal substantially fills a space defined in the stack that corresponds to the cage. In one form, the space includes slots or related channels formed in the stack that upon filling with the molten metal become longitudinal bars that form electric current loops with end rings of the cage. By heating the stack and maintaining it at a temperature high enough to keep the molten metal in a substantially molten state at least long enough for it to flow through the slots of the stack, premature freezing of the molten metal is avoided. In addition, by providing low pressure to the molten metal in conjunction with the elevated temperature in the stack, flow is promoted to ensure a substantially porosity-free, fully dense squirrel-cage for the rotor.

A method of making a squirrel cage rotor of copper material for use in AC or DC motors, includes forming a core with longitudinal slots, inserting bars of conductive material in the slots, with ends extending out of opposite ends of the core, and joining the end rings to the bars, wherein the conductive material of either the end rings or the bars is copper. Various methods of joining the end rings to the bars are disclosed including electrofriction welding, current pulse welding and brazing, transient liquid phase joining and casting. Pressure is also applied to the end rings to improve contact and reduce areas of small or uneven contact between the bar ends and the end rings. Rotors made with such methods are also disclosed.

A hybrid induction motor includes an inductive rotor and an independently rotating permanent magnet rotor. The inductive rotor is a squirrel cage type rotor for induction motor operation at startup. The permanent magnet rotor is axially displaced and variably coupled to the inductive rotor (or to a motor load) through a clutch and is allowed to rotate independently of the inductive rotor at startup. The independently rotating permanent magnet rotor quickly reaches synchronous RPM at startup. As the inductive rotor approaches or reaches synchronous RPM, the coupling between the inductive rotor and the permanent magnet rotor increases until the two rotors are coupled at the synchronous RPM and the motor transitions to efficient synchronous operation.

The invention relates to a permanent magnet synchronous motor of sinusoidal pole width modulation, belonging to the technical field of motors. The motor comprises a rotation shaft (1), a bearing (2) which is matched with the rotation shaft (1), an end cover (3), a stator core (5) and a rotor core (6) which is matched with the rotation shaft (1); the motor is characterized in that n distribution-typed permanent magnetic pole (7), with unequal widths and intermittent spacings, are fixed at the circumference of the rotor core (6); the central line of the distribution-typed permanent magnet of No. i (i is equal to 1, 2, 3,..., n) and the central line of a magnetic pole have an electric angle of Theta which is equal to (2i-1)*pi/(2n); the width arc angle Alpha of the distribution-typed magnetic pole of No. i is equal to cos((i-1)*pi/n-cos(i*pi/n)); a squirrel cage rotor (8) is arranged outside the rotor core (6) and carries out circumference separation and circumferential positioning on the distribution-typed permanent magnetic pole (7). The invention has the advantages of high work efficiency, stable and reliable operation and obvious energy-saving characteristic.

A fan assembly includes at least one fan blade for moving air and a line-start permanent magnet (LSPM) motor having a shaft. The fan blade is coupled to the shaft of the line-start permanent magnet motor such that rotation of the shaft causes rotation of the fan blade for moving air. Also disclosed is an LSPM motor that includes a shaft and a squirrel cage rotor having a plurality of embedded magnets. The LSPM is configured to permit limited rotation of the squirrel cage rotor relative to the shaft as a speed of the motor approaches a synchronous speed. This LSPM motor can be used in a variety of applications including, without limitation, fan assemblies, fluid pumps, etc.

A novel air gap magnetic field electromagnetic modulation permanent magnet motor with a double squirrel cage structure is a novel direct drive motor for directly realizing low-speed and high-torque output by means of electromagnetic modulation of high-speed air gap rotation magnetic fields, and can be applied to the transmission field of wind power generation, electric vehicles, ship drive and the like needing direct drive. The permanent magnet motor is characterized by comprising a stator with 2ps poles, an electromagnetic modulation hollow double squirrel cage rotor and a permanent magnet rotor with 2pr poles, wherein the stator, the electromagnetic modulation hollow double squirrel cage rotor and the permanent magnet rotor are of a radially concentric structure and have two air gaps respectively corresponding to two air gap rotation magnetic fields with different synchronous speeds. When running, three-phase symmetric alternating current flows through a stator winding 3 in the stator core 4 to generate the high-speed air gap rotation magnetic fields with fewer 2ps poles, the high-speed air gap rotation magnetic fields are modulated into high-order harmonic rotation magnetic fields with more 2pr poles by squirrel cages 13 of the hollow double squirrel cage rotor through electromagnetic modulation, and accordingly, the permanent magnet rotor is driven at a low speed and a high torque.

The invention relates to a squirrel-cage rotor for an asynchronous machine. In order to increase the electrical efficiency for a cage rotor composed of two materials, the cage rotor comprises a rotor core (1) having grooves (3), end rings (5) of a first material that are cast onto the rotor core on the end face, and conductors (4) that are arranged in the grooves and that are made of a second material that has an electric conductivity that is higher than the electric conductivity of the first material, wherein the conductors (4) comprise a coating (8) made of a coating material on the surface of the conductors, wherein the coating adjoins the second material of the conductors (4) by means of a first alloy layer (2) made of the second material and the coating material and adjoins the cast first material by means of a second alloy layer (9); made of the first material and the coating material.

The invention proposes a system for driving a compressor, comprising an induction motor (2) for driving the compressor (3), said induction motor including a squirrel cage rotor, and a controller (1) for controlling the induction motor, said controller comprising a memory for storing drive patterns for driving the induction motor, a first frequency generation means for generating a field frequency based on a field command and/or a second field generation means for generating a voltage frequency based on a voltage command, wherein a drive pattern in extracted from the memory based on the generated frequency or frequencies. Alternatively, the invention proposes a system for driving a compressor, comprising an induction motor (2) for driving the compressor (3), said induction motor including a squirrel cage rotor, and a controller (1) for controlling the induction motor, wherein the controller is adapted to distinguish between a steady state and a transient state of the induction motor.

An electric machine rotor, which extends along an axis of rotation, including a short-circuit cage, the or each first connection means between a respective first end part of the or each bar and the first short-circuit ring includes a plurality of flexible electrically conductive blades.

In order to prevent, among other things, fatigue failures in squirrel-cage rotors of electrical machines, the invention provides that the squirrel-cage winding is comprised of flexible conductors.

A retarded electric motor designed as a series motor or an asynchronous motor having a squirrel cage rotor. A valve is provided for switching between motor operation and braking operation. During motor operation the motor is operated in a known configuration as series motor or as asynchronous motor. If configured as a series motor, the valve (S₁, S₂, S₃) allows to bypass the armature and to operate the motor as an externally excited direct current generator when switching into braking operation. If configured as an asynchronous motor, a switch is utilized to disconnect at least two field windings from mains. A valve is utilized to excite the motor externally from mains with a pulsating direct current during braking.

A squirrel-cage rotor includes a rotor core formed having a plurality of slots, a plurality of conductor bars inserted into the slots respectively and made of copper or copper alloy, two conductor end rings joined to the plurality of conductor bars on both end faces of the rotor core and made of copper or copper alloy and a reinforcing-member end ring attached to at least one of the conductor end rings and made of material having a specific strength greater than that of either copper or copper alloy. The plurality of conductor bars are arranged so as to extend through the conductor end rings and the reinforcing-member end ring. Consequently, the rotor can be manufactured by any manufacturing method but die-casting. Further, the conductor end rings can be reinforced with an easily-obtainable material and additionally, the junction of conductor end rings can be easily viewed from an outside.

A squirrel-cage rotor and a production method thereof, the rotor having conductors with sufficient strength. In the invention, conductor particles are sprayed onto a core and/or conductive bars in a solid-state. As a result, in the coating material, the enlargement of the crystal grain of the conductors is significantly restricted, whereby conductive end rings are connected to the core and/or the conductive bars. Since conductor particles do not melt, a gap formed by thermal contraction when the conductor melts between different kinds of members is prevented from being formed. Therefore, the deterioration of the conductor may be limited, and the conductor may have sufficient strength. The reliability of the rotor is improved.

The casting process of copper squirrel cage rotor includes the following steps: 1. pre-treating silicon steel sheet through heating in a furnace a 500-600 deg.c and cooling outside the furnace to form oxide film automatically; 2. laminating, pressing and installing mold; 3. heating the pressed silicon sheets inside furnace to 650-750 deg.c, and setting in a centrifuge; 4. smelting copper material; 5. casting to the squirrel cage groove and mold cavity while turning on the centrifuge to exhaust air; and cooling outside the furnace. The present invention has the advantages of power saving of motor, reduced motor size, saving in material, low cost, etc.

A squirrel cage rotor structure used in connection with an electrical machine is formed from a high-strength, high-conductivity, and heat-treatable aluminum alloy, e.g., a T61 tempered aluminum alloy, such as A6101-T61. The resulting structure has improved strength compared to conventional pure aluminum structures, while at the same time limiting the reduction in electrical conductivity.