The pattern of a few kinds of timing of three-phase asynchronous electromotor

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Formula of rotate speed of three-phase asynchronous electromotor is: N=60f/p(1-s) from go up form is visible, change F of power supply frequency, electromotor extremely logarithm P and turn poor rate S all but too the purpose to change rotate speed. From the point of the essence of timing, the synchronous rotate speed that different timing pattern no more than is change AC motor or do not change synchronism to turn two kinds. The rotor that uses the timing method that does not change synchronous rotate speed extensively in producing machine to have electromotor of the type that wind a string strings together the resistor timing, behead wave timing, timing that cluster form and applied electromagnetism to turn coincidence of poor clutch, hydraulic implement, the timing such as oily film clutch. Change synchronous rotate speed have a change multi-speed motor of stator pole logarithmic, the frequency control that changes stator voltage, frequency has can wait without inverting electromotor timing. In light of the viewpoint of specific power consumption from timing, have efficient timing method and method of small effect timing two kinds: Poor rate turns when efficient timing points to changeless, because this is not had,turn poor loss, be like multi-speed motor, frequency control and can will turn the timing method that poor loss reclaims (if string together degree timing,wait) . Have turn the timing method of poor loss belongs to small effect timing, if rotor strings together resistor timing method, energy is with respect to loss in rotor loop; The timing method of electromagnetism clutch, energy loss is in clutch coil; Hydraulic coincidence implement timing, energy loss closes in fluid couple implement in oil. Turn to poor loss expands along with timing scope and increase generally speaking, if timing scope is not big, energy loss is very small. One, change extremely logarithm timing method method of this kind of timing is use change stator winding receive diamonds type to come stator of change basket electromotor extremely logarithm achieves timing goal, the characteristic is as follows: Have harder physical characteristic, stability is good; Without turn poor loss, efficiency is tall; Wiring simple, control convenient, price is low; Have degree timing, class difference is bigger, cannot obtain flowing timing; Can with pressure regulating timing, electromagnetism turns poor clutch cooperates to use, acquire more efficient flowing timing character. This method applies to the manufacturing machine that does not need stepless speed regulation, like metallic cutting machine tool, elevator, remove heavy equipment, fan, water pump to wait. 2, the frequency that frequency control of frequency control method is power source of change electromotor stator, change the timing method of its synchronism rotate speed thereby. Frequency control system is main equipment is the transducer that provides frequency conversion power source, transducer can be divided into communication - dc - communication transducer and communication - communication transducer two kinds big, at present home is used mostly hand in - straight - hand in transducer. Its characteristic: Efficiency is tall, there is additional loss in timing process; Applied range is wide, can use at basket model asynchronous electromotor; Timing scope is big, character is strong, precision is tall; The technology is sophisticated, cost is high, safeguard overhaul difficulty. This method applies to claimed accuracy performance of tall, timing is better circumstance. 3, method of the timing that cluster form strings together degree timing is to point to to be strung together in loop of rotor of electromotor of the type that wind a string adjustable add electromotive force comes to those who change electromotor turn poor, achieve the goal of timing. Turn for the most part the place of add electromotive force that poor power is strung together is absorbed, recycle generation is additional device, turn those who absorb to poor power returns electrified wire netting or change energy to try to use. According to turning poor power is absorbed use means, the timing that cluster form can be divided for electric machinery the timing that cluster form, mechanical timing that cluster form and brilliant brake provide form of the timing that cluster form, use brilliant brake to be in charge of the timing that cluster form more, its characteristic is: Can turn timing process mediumly to poor loss passes on electrified wire netting or produce machinery to go up, efficiency is taller; Plant capacity and timing scope become direct ratio, investment province, apply to timing scope to be in rated rotate speed 70 ％ - on the manufacturing machinery of 90 ％ ; When timing device breakdown can switch comes to move amain, avoid stop production; Brilliant brake runs on the low side of factor of power of the timing that cluster form, harmonic impact is bigger. This method agrees with fan, water pump and rolling mill, mine is used on promotion machine, extruder. 4, rotor of electromotor of the type that wind a string strings together resistor timing method to circle rotor of electromotor of line type asynchronous to string together ballast resistor, make of electromotor turn poor rate is increased, electromotor moves below inferior rotate speed. The resistance that strings together is greater, the rotate speed of electromotor is lower. This method equipment is simple, control is convenient, but turn poor power is used up with calorific form go up in resistor. Belong to timing having class, physical characteristic is softer. 5, stator is pressure regulating when timing method should change the stator voltage of electromotor, can get a group of different physical characteristic curves, gain different rotate speed thereby. Become direct ratio as a result of the torsion of electromotor and voltage square, accordingly the biggest torsion drops a lot of, its timing scope is lesser, make general basket model electromotor applies hard. To enlarge timing scope, pressure regulating timing should use rotor resistance big basket model electromotor, if be offerred only pressure regulating the pitching moment motor that timing uses, perhaps establish ties on electromotor of the type that wind a string frequency quick resistor. Run range to enlarge stability, be in when timing 2: The circumstance of 1 above should use feedback to control in order to achieve goal of self-adjusting rotate speed. Pressure regulating the main unit of timing is a power source that can provide voltage to change, current and commonly used pressure regulating means has series connection saturation reactor, be in charge of from Ou transformer and brilliant brake pressure regulating wait for a few kinds. Brilliant brake canal is pressure regulating means is optimal. Pressure regulating the characteristic of timing: Pressure regulating timing circuitry is simple, yi Shi shows automata; Pressure regulating poor power of process change trains is used up with calorific form in rotor resistor, efficiency is inferior. Pressure regulating timing applies to the manufacturing machinery under 100KW commonly. 6, electromotor of timing of electromagnetism of method of timing of electromagnetism timing electromotor by basket model electromotor, electromagnetism turns poor clutch and dc excitation power source (controller) 3 parts composition. Power of dc excitation power source is lesser, normally by single-phase wave or half Quan Bojing brake are in charge of rectifier to comprise, change what brilliant brake is in charge of to guide current flow angle, can change the size of excitation electric current. Electromagnetism turns poor clutch is mixed by armature, magnetic pole 3 parts comprise excitation winding. Armature and latter do not have mechanical connection, can turn freely. Armature and connection of electromotor rotor coaxial weigh active part, drive by electromotor; Magnetic pole calls driven the part with shaft coupling and laden axis butt joint. All be when armature and magnetic pole dormant when, connect like excitation winding with dc, criterion along air gap circumferential surface will form a certain number of is opposite the magnetic pole with alternant polarity of N, S, its magnetic flux passes armature. Follow when armature procrastinate when moving electromotor to rotate, because move relatively between armature and magnetic pole, make armature induction generates vortex flow consequently, this backset and magnetic flux interaction produce torsion, drive the rotor that has magnetic pole to rotate by same way, but constant of its rotate speed the rotate speed N1 under armature, this is one kind turns poor timing pattern, fluctuant turn the dc excitation electric current of poor clutch, the output torsion of changeable clutch and rotate speed. The timing characteristic of electromagnetism timing electromotor: Plant construction and control line way are simple, run reliable, maintenance to go to the lavatory; Timing flowing, stepless speed regulation; Do not have humorous influence to electrified wire netting; Speed loses big, efficiency low. This method applies to medium, small-power, the demand is flat slip, short when the production that low speed runs is mechanical. 7, coupler of hydraulic of method of hydraulic coupler timing is device of a kind of hydraulic power, comprise by impeller and turbine commonly, their a general designation works annulus, put in sealed housing. The working liquid of certain amount is filled in housing, next whirl is driven in prime mover when impeller when, be in among them liquid to suffer blade is driven and rotate, when turbine is being entered along impeller outer shroud below centrifugal force effect, be in same turn to give turbine blade up with thrust, make its drive manufacturing machinery to run. The motivation of hydraulic coupler turns losing the size that fluid amount charges relatively inside ability and carapace is consistent. In working process, change rate full fluid to be able to change the turbine rotate speed of coupler, make stepless speed regulation, its characteristic is: Power accommodation is big, can satisfy differ to thousands of kilowatt from a few tile the need of power; The structure is simple, the job is reliable, use reach maintenance to go to the lavatory, and cost is low; Size is small, can allow big; Control adjustment is convenient, implement automation easily. This method applies to the timing of fan, water pump. CNC Milling