CN1365177A - Double-magnetic field motor - Google Patents

Abstract

The double magnetic field electric machine has two independent main magnetic fields in two different air gaps. There are two stators with separate working windings and exciting windings, two rotors with separate, symmetrical three-phase windings with opposite phase order and connected together, and one exciting system in the top providing the motor with autoamtic exciting power source. The electric machine is designed based on double magentic field electric machine principle and may be designed as one power generator or one motor. The double magnetic field power generator may maintain normal operation in the case of drastically changed load or even short-circuit; and the double magnetic field motor will not produce surge current during starting and may be used as synchronous motor or double speed motor. The double magnetic field electric machine is superior to available asynchronous and synchronous motors.

Description

Double-magnetic field motor

The present invention relates to a kind of double-magnetic field motor.

Existing asynchronous motor produces huge surge current and influences electric equipment operate as normal on every side when starting, and it can only influence the adjusting speed accuracy of equipment with the asynchronous speed operation.Existing synchronous motor since start because of difficulty and complex structure can not extensive use.Existing synchronous generator may cause major accident when suddenly-applied short circuit takes place.Existing asynchronous generator needs to absorb a large amount of exciting currents or need The parallel power condenser to generate electricity from electrical network, or the like, existing asynchronous machine that is widely used at present and synchronous machine intrinsic above-mentioned shortcoming cause many troubles to the user.

Purpose of the present invention just provides a kind of new Principle of Electric Engine.Can manufacture and design the double-magnetic field motor of various uses according to this new principle, this double-magnetic field motor has overcome the shortcoming of above-mentioned existing motor fully, and its complex art economic index is apparently higher than existing asynchronous machine and synchronous machine.

Double-magnetic field motor has two main fields: stationary magnetic field and rotating magnetic field.Fig. 1 is the double-magnetic field motor schematic diagram, wherein: 1, asynchronous stator, 2, asynchronous rotor, 3, asynchronous air gap, 4, synchronous air gap, 5, step in week rotor, 6, stator synchronously, 7, excitation system (1. current transformer, 2. and 3. rectification module, 4. fly-wheel diode), the asynchronous number of poles of P-, P '-synchronous number of poles, n ₁-air-gap rotating magnetic field rotating speed, n ₂The rotating magnetic field rotating speed of-rotor 2, n ₂The rotating magnetic field rotating speed of '-rotor 5, the mechanical separator speed of n-rotor, f ₁The frequency of-stator 1, f ₂The frequency of-rotor 2.f ₂The frequency of-rotor 5.From Fig. 1 as seen, double-magnetic field motor is to be made of two parts: the similar conventional wound asynchronous machine of first claims asynchronous part; The similar common pivot-rotatable type synchronous machine of second portion claims sync section.The main field of asynchronous part is a rotating magnetic field; Sync section is a stationary magnetic field.Two main fields are separate, and the direct negative-phase sequence of two-part rotor winding connects.As three-way motor, double-magnetic field motor is also followed the motor principle of reversibility, has two kinds of running statuses of generator and motor, and two states can be changed mutually.According to running status, divide into " double-magnet generator " and " two magnetic fields motor ".When double-magnetic field motor becomes generator during by prime mover driven; When by mains supply, become motor.

The action principle of two generators is described below: at first make generator that remanent magnetism (can obtain in the DC power supply of excitation winding two terminations outside) is arranged, under the remanent magnetism effect, rotor rotated 5 is promptly set up electromotive force, two rotor windings promptly produce electric current, this electric current forms the winding of rotating magnetic field cutting stators 1 and sets up output potential at rotor 2, and this electromotive force acts on the excitation winding of stator 6 and produces exciting current remanent magnetism is strengthened through excitation system 7.So impel the output potential of stator 1 constantly to rise behind the ringing until the stationary value of setting.When generator is connected load.Load current produces the demagnetizing effect of armature reaction and is recompensed by current transformer felling electric current 1., to keep the constant of output voltage.

The action principle of two magnetic fields motor is described below: promptly form rotating magnetic field and drive the rotor rotation at air gap 3 after stator 1 is connected electrical network, electric network source makes stator 6 acquisition excitations and sets up stationary magnetic field through excitation system 7 simultaneously.Rotor 2 and rotor 5 are set up electromotive force at winding separately respectively respectively under these two main field effects, these two rotor electromotive forces interact, rotor speed just settles out when both frequencies equate, this stabilized (steady-state) speed is the synchronous speed of two magnetic fields motor.So two magnetic fields motor is a synchronous motor.

According to Fig. 1 and Electrical Motor theory, can derive two important formula of generator: $f_1=\frac{(P+P^{\′})n}{60}\left(\mathrm{Hz}\right)---------\left(1\right)$

Formula (1) illustrates that the number of poles of two generators equals the number of poles sum of two part.From formula (1) and figure (1) as seen, two generators are actually by the two-stage power supply to be formed: first order power supply is a synchronous generator; Second level power supply is a resolver.This composition mode is equivalent to transformer load and generator be kept apart, load current just can not directly produce armature reaction to generator field like this, in this case, no matter how fierce change of load, even output short circuit, generator can not be subjected to directly to influence and still can normally move, two outstanding advantages of generator that Here it is.

In like manner also can derive two important formula of magnetic field motor: $n=\frac{60f_1}{P+P^{\′}}(r/\min )-------\left(2\right)$

Formula (2) illustrates that the number of poles of two magnetic fields motor also is the number of poles sum of two parts.From formula (2) and figure (1) as seen, two magnetic fields motor is actually two coaxial motor compositions: one is synchronous motor, and another is an asynchronous motor.Bear startup by asynchronous motor and appoint wound, and transmit the electric energy of electrical network to synchronous motor.In start-up course, the back-emf of synchronous rotor is suppressing the sharp increase of starting current all the time, thereby has eliminated the phenomenon of start-up course generation surge current, so just can realize frequent starting and braking safely and reliably.When startup finish reach synchronous speed after motor promptly enter stable operation.As cut-out field power supply in service, motor promptly rises to asynchronous speed by synchronous speed, so two magnetic fields motor is actually two-speed motor.

Concrete structure of the present invention is shown in figure (2).Motor is horizontal type structure (also can be designed to vertical), asynchronous rotor 5 and synchronous rotor 10 and fan 7 are installed in rotating shaft 1, asynchronous stator 4 is installed in the support 3, stator 9 is installed in the support 8 synchronously, excitation system 6 is installed in the top of support 3, the binding post of motor is also installed in its inside, and end cap 2 and 11 is assembled into integral body together to support, stator, rotor.

From Fig. 2 as seen, double-magnetic field motor does not have charged sliding contacts such as the necessary carbon brush of common electric machine, slip ring or commutator, the electronic component that does not yet have rotating rectifier, surge suppressor etc. to damage easily.Need not to install damping winding.Cooling fan can improve the motor cooling condition in the middle of placing motor.The element of excitation system has seldom reduced the probability and the manufacturing cost of electrical fault.

Claims (3)

1, a kind of double-magnetic field motor has two main fields: stationary magnetic field and rotating magnetic field; Have two stators and two rotors and the easy excitation system of a cover.

2, double-magnetic field motor according to claim 1 is characterized in that two separate main fields, and the direct negative-phase sequence of three-phase rotor winding of two cover symmetries connects.

3, double-magnetic field motor according to claim 1 is characterized in that the easy excitation system of a cover, gathers load voltage and the load current automatic magnetic exciting power supply as double-magnetic field motor.

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