High Voltage Squirrel Cage Motor



1.General
    AKK SERIES, 6KV and 10kV, 2-pole motors are new series products which have been developed in 90’s and designed with an advanced technology, so as to be particular about material selection and to be fabricated with a fine process. In this condition, motors will have such features of energy economy. low-noise, small vibration and convenient in mounting and repair but also these series of 10kV motor may be connected directly to 10kV grid with the result that these series may also have these features of simplification of facility ;economy of investment and reducing of energy consumption.
    The power grade ,electric property, mounting dimensions and tolerance of AKK series are coincident with GB755 < Rotating electric motor rating and property > .International, Electrical committee standard IEC34-1
< Rotating electric motor rating and property > and machinery-profession standard JB/17593 etc.The power grade, electric property, mounting dimensions and tolerance of YK series are coincident with GB755,IEC34-1 and JB/T2225 < Large sized ,three-phase, high speed squirrel cage asynchronous motor technical specification >.The degree of protection for outer case, cooling method, and mounting mode are on the base of GB4942.1 respectively and coincident with international committee standard IEC34-5.1EC34-6 and IEC34-7.The degree of protection for outer case, cooling method and mounting mode of these series motors are shown in following table.

If customer would need the protective degree and cooing method are different from those shown in above table, we can provide, as for AKK series, we can provide tube-ventilation and hose-proof mode.
2 .Application ranges
These serial motors may be used to drive blower and water pump machinery for electric power, metallurgic, chemical, paper-making and mining etc industries.
    Normal working conditions for motors:
    a. Sea level not over 1000m;
    b. The environment temperature not over 40oC the lowest environment for motor with rolling bearing is 5oC for AK (air-water cooling) and YKS series motors is 5oC
    c. As AK (air-water cooling) and YKS series motors,  cooling water temperature at the cooler outlet is not over 33oC and the lowest temp is 5oC
    d. In moist month, the monthly average highest relative humidity is 90%,at the same time, the monthly average lowest temp is not over 25oC
    e. The frequency of power source is 50Hz±2%;
    f. The variation of work voltage is not over±5oC
    g. Motor’s rating is continuous running duty-type s1.
3. Structure descriptions
    The construction of motor is a world wide current tank shape ,the motor frame is made of steel plate and welded into a form, with good rigidity and light weight, awhile the protective cover or cooler is removed aside, we may watch and touch the motor’s inner parts, thus it is convenient for mounting and maintenance.
    The stator with outer-press-assembly structure is adopted ,stator as made of F-class insulation and electric-corona-proof material, a special banding technology is used for winding end part fastening, the whole stator is treated by VPI with F-class solventless varnish, by this means, motor will possess good and reliable insulation properly and moisture-proof, anti-impact capability.
    There are two modes for the squirrel-cage rotor i.e. casting aluminum and copper-bar mode. Casting aluminum rotor is cast with pure aluminum, there will never be bar-broken appearance and running reliability, as to the copper-bar squirrel cage rotor, it will be processed by an advanced and reliable medium frequency induction welding technology, then to be done by fastening treatment in the slots, it is effective to protect the coppers bars to be broken up.
    There are two bearing models i.e. rolling type and sliding type, there must be in accordance with the motor’s power and speed to make a determination. The bearing basic protective degree in IP44, if the protective degree is higher, the bearing protection must be also heightened.
    As for sliding bearing, there are two models i.e. end-shield type and pedestal type, the pedestal type sliding bearing is used for YK series motors. but the motor must have a mounting frame.
    Normally the forced circulating lubrication is adopted for sliding bearing; customer must be in accordance with the stipulation mentioned by our co. to make up bearing lubricating oil.
    For these motors using rolling bearing, there is an adding and exhausting oil device to be prepared for motor non-stopping usage.
    The blower mounted on the rotor is a high efficiency and low noise axial one ,due to the fact that the blower possesses directionality that the motor must run by a pointed direction ,don t reverse.
    The main terminal box in a sealed structure, its protective degree is IP54. Normally AKK series motors will have two same dimensions cylindrical axle extensions. User may arbitrarily choose one for drive end.
4. Squirrel cage rotor aSynchronous motor starting
 For protection against squirrel cage rotor of aSynchronous motor starting under a too large load to be broken down in an early time, we have made a calculation of the rotor’s temperature rise and stress with the computing technique.
    There would suggest customer to check;
   (1) The moment of inertia (after being converted to motor’s rotating speed) of the rotating part of driven mechanical equipment should  not over these value of (loading J) item show in the technical data table;(2) Customers should guarantee the voltage of electric network across the motor s terminals not lower than 85% of the rated value during starting;(3) The resisting-torque characteristic of driven machinery is such kind as water pump and ventilator.
    Under these above mentioned conditions, motor may be permitted to be started of actual cold condition by two times continuously, or at hot condition for once only, the interval of two times starling is natural stoppage. If there is need to start over above limit, it must wait for one hour there after.
    If the moment of inertia of the mechanical rotating part of the machinery being driven is over the value shown in (load j) item of technical data, or there is a requirement to start motor frequently, or it in possible to start the motor under heavy loading, it is necessary to contact with our corp. for a negotiation, thus for there will let do a special design to guarantee the motor having a reliable starting.6.
5.Notice:
a. To check the moment of inertia (after being converted to motor s rotating speed) of rotating part of the machinery being driven, please to consult the content of fifth section Squirrel cage rotor aSynchronous motor starting.
    b. If working condition being changed or other request, it is necessary to sign a technical agreement before order;
    c. Due to the technology development and the revise of relative home and foreign standards as well as the technical values and size will be varied, we would not notify later, after ordering, please to ask our Corp. for the formal general overall drawing.