Device for start-up and brushless excitation of non-contact synchronous machine

FIELD: electricity.

SUBSTANCE: device includes the main synchronous machine (1), inversed synchronous exciter (2) of the main synchronous machine in a common magnetic system with an asynchronous subexciter made in the form of an asynchronous motor, excitation winding of the synchronous exciter, winding located on the rotor, a rotating semiconductor converter and an excitation control. It is equipped with switching device of modes (7), metre (8) of rotor rotation frequency of the main synchronous machine with an inlet and an outlet and winding switches (9, 10). Winding is made in the form of coil groups in a non-salient pole magnetic system of the stator and the rotor, and the magnetic system is combined as to magnetic flows with smaller number of poles for motor operation and large number of poles for generator operation.

EFFECT: enlarging functional capabilities of an exciter owing to providing operation in motor and generator operating modes at reduction of material consumption, increasing efficiency, simplifying the structure and reducing material consumption for production of the exciter.

3 dwg

 

The invention relates to electrical engineering and can be used for start-up and contactless synchronous electric machines for special purposes, such as on-Board systems of alternating current of constant frequency 400 Hz.

The level of technology

A device for starting and brushless excitation synchronous machines, including converted synchronous exciter, excitation winding of which is connected with a controlled stationary rectifier connected across the power transformer to the armature winding of the synchronous machine and induction motor-pathogen combined on a single magnetic core with additional stator windings are electrically combined with the excitation winding converted synchronous exciter, and the armature winding of the synchronous exciter and the rotor winding of an induction motor-exciter are connected in series and through a rotating rectifier connected to the excitation winding of the synchronous machine. The main stator winding of an induction motor of the pathogen through the starting contacts dip switch is connected to AC power, and through work contacts, stationary thyristor Converter and the power transformer is connected to the armature winding of the synchronous machine, induction motor-pathogen has will complement the optimum winding on the stator, made electrically combined with the excitation winding converted synchronous exciter connected with its three-phase terminals to the resistance (A.S. USSR №649111, MKI2NR 1/46, publ. 1979).

The disadvantages of the known devices is the presence of an additional stator winding induction motor exciter, power transformer, block starting resistance of the rectifier, which significantly complicates weight design, making it difficult to use the device in the on-Board conditions. In addition, the probability of failure of rotating diodes of the rectifier at start-up and self-synchronization synchronous machine, which reduces the reliability and lifetime of the device.

A device for starting and synchronous machine, consisting of a synchronous generator, synchronous exciter converts designs, podozrevala made structurally separate electric synchronous machine with electromagnetic excitation and automatic excitation regulator. The field winding of the exciter through the static Converter connected to the terminals of the anchor coil podozrevala. Armature winding of the exciter through the rotary Converter is connected to the excitation winding of the synchronous generator. Automatic regulator who is here fed from the anchor coil podozrevala (Glebov N.A., Loginov SR excitation System and control of synchronous motors - HP: Energy, 1972. C.113).

A disadvantage of the known device is the design complexity due to the presence of three electric machines in various magnetic systems and placed on the same shaft that extends and weight to the unit, increases the cost and complicates the manufacturing process and operation of the device.

The closest solution to the invention to the technical essence and the achieved technical result is a device selected as a prototype), consisting of excited (main) synchronous machine that converts synchronous exciter, and asynchronous induction of podosphaera combined in a common magnetic system, winding connected via a static Converter to anchor the winding asynchronous podozrevala located on the rotor windings, rotating semiconductor Converter and regulator of excitation (RF patent No. 2095923, IPC: NC 19/38, publ. 1997). Listed essential characteristics of the prototype coincide with the essential features of the claimed invention.

A disadvantage of the known constructions is the presence of three electric cars made in the total magnetic system and the presence of four located on the stator windings, the presence of part of the pole is in permanent magnets, two static controls, which increases the cost and complicates the manufacturing process and operation of the device. In addition, the presence of four windings makes the device excessively material and complicates its use for on-Board conditions.

Objective of the claimed invention is to improve the starting characteristics of contactless synchronous machine, consisting of a main contactless synchronous machines and brushless asynchronous-synchronous exciter, increase reliability, and simplify the design to enable the work on Board the aircraft.

The technical result of the present invention is to enhance the functionality of the pathogen by providing work in motor and generator modes while reducing material consumption, increase efficiency, simplify the design and reduce the material intensity of production of the pathogen through the use of in motor and generator modes of operation the total magnetic system (the combination of magnetic circuits) and the same coil groups (combination of electrical circuits).

The technical result is achieved in that the device for start-up and brushless excitation synchronous machine, including the main synchronous machine that converts synchronous exciter main synchro is Noah machines in the total magnetic system with asynchronous podozritelen, made in the form of an induction motor, the field winding synchronous exciter located on the rotor winding and rotating the semiconductor transducer and the excitation regulator with switch modes and switches the windings, while the latter is in the form of coil groups in neravnopolochny magnetic system of the stator and rotor, and the magnetic system is made aligned with the magnetic flows with a smaller number of poles for the motor operation mode and a large number of poles for generator operation mode when this coil groups of the stator winding is made in the form of switched in two parallel-connected three-phase star for inclusion in the motor mode, the coil groups of the winding rotor made for motor mode devyatietazhnyj short-circuited, and for generating three-phase mode with three parallel coil groups within each phase, the switch of modes associated with the winding switches to connect the DC to zero conclusions three-phase star in the generator mode of operation and switching of the main synchronous machine on the external network.

Thus, simplifying the design and reducing the consumption of materials is achieved through the use of generator and motor modes of pathogen same bobbin is winding groups and the total magnetic system. The invention is illustrated by drawings, in which:

Figure 1 shows the electric diagram of the device.

Figure 2 shows a chart EMF rotor winding for polarity p2=3.

Figure 3 shows the diagram EMF rotor winding for a three phase pole p1=1 motor mode.

Device for starting and brushless excitation contactless synchronous machine consists of a main contactless synchronous machine 1 with asynchronous-synchronous exciter (DIA) 2 with a combined winding 3 of the stator and a combined winding 4 of the rotor, the rotating semiconductor Converter 5, the excitation current controller 6, switch 7 modes, meter rotor speed contactless synchronous machine 8 and the contacts of the switches 9, 10, 11. Combined armature winding 4 DIA 2 in the rotating semiconductor Converter 5 is connected to the excitation winding of the synchronous machine 1. Combined stator winding 3 DIA 2 its zero pins 01 and 02 are connected through the working contacts of the switch 9 through the switch of modes 7 to the output circuit of the DC excitation current controller 6, and its three-phase pins 1A, 1B and 1C winding 3 through the starting contacts of the switch 10 switch modes 7 is connected to an external AC power of constant frequency 400 Hz. The contacts of switch is the breaker 11, associated with the switch 7, are used for connection of the synchronous machine 1 to the three-phase AC network.

An example implementation

Asynchronous-synchronous exciter 2 is pavlopoulou electric machine with combined windings of the rotor and stator are located in a common magnetic core and designed to be placed in the same housing with a synchronous machine.

The stator of the asynchronous-synchronous exciter 2 contains Z1=groove 24, which in General is equal to the product of the number of pairs of poles in motor mode 2p1, the number of phases of the motor stator winding mode m1d and the ratio of the number of slots per pole and phase q1, that is, Z1=2p1×ml×2p1.

Combined winding 3 of the stator in this case is made of single-layer, three-phase (1A, 1B, 1C) with diametral pitch and number of pairs of poles for motor mode 2p1=2. Energized such winding direct current through the zero findings 01 and 02 in the space of the air gap asynchronous-synchronous exciter creates a stationary magnetic field with a number of poles equal in the General case, the product of the number of phases of the motor mode to the number of pairs of poles of the motor mode, that is, 2P2=m1D×2p1. For a given winding number of pairs of poles of the generator mode is equal to 2P26.

For the combined winding rotor asynchronous-synchronous exciter with three identical coil groups in the phase-pole versions with p2=3 (for phase 2A is number 1', 4', 7') of the coil groups of each phase shifted relative to each other at the p2=3-pole field generator on the angle α=p1×2π=360°. The coil groups are connected in parallel and form a phase generator (for example, 2A-0). Likewise, the parallel connected coil groups in the two remaining phases of the generator (2B-0; 2S-0).

Combined winding 4 of the rotor asynchronous-synchronous exciter 2 is the number of pairs of poles of the motor mode 2p1=2 and the number of pairs of poles of the generator mode 2P2=6, made in two-layer design phase in the generator mode is equal to three (m2G=3), connected in a2G=p2/p1=3 three parallel branches, placed at Z2=36 slots. In the General case, the number of grooves of the rotor Z2is determined by the product of the number of pairs of poles of the motor mode 2p1the number of phases of the motor winding mode of the rotor M2Dand the ratio of the number of slots per pole and phase q2, that is, Z2=2p1×m2D×q2. And q1≠q2.

Step rotor winding field generator with pole versions R2=3 is chosen somewhat larger pole division. In the engine operation mode vozbuditelei m 2G=3 phase generator form a separate cage system, is equivalent to m2D=a2G×m2G=9 phase winding for a three phase pole p1=1 motor mode (Popov V.I., Rotary transducers frequency. - Moscow. Energy, 1980, 175 C.).

Combined winding 4 of the rotor asynchronous-synchronous exciter 2 simultaneously performs the functions of two opposite-pole windings: devyatietazhnoe cage for p1=1-pole field of the motor and three-phase for p2=3 - pole field generator. It is made with 3 parallel branches in the phase of the generator, the number of which depends on the ratio of pairs of poles 2p2/2p1. For a given rotor winding three identical coil groups in the phase generator (phase 2A 1', 4', 7') are shifted relative to each other at the p1=1 - pole field of the motor at an angle α2=p1/p2×2π=120° and at their parallel connection to form a three-phase symmetrical short-circuited system(1', 4', 7') for motor operation mode (Fig 3)

While on the findings of the phase generator 2A-0, 2B-0, 2S-0 absent EMF slip because of the symmetry of the parallel branches. All three phases of the generator consists of three separate cage system for motor field pole p1=1, is equivalent to the total devyatietazhnoe the rotor winding.

<> The proposed device for start-up and brushless excitation contactless synchronous machine operates as follows.

Starting mode. The signal switch 7 through the contacts of switch 10 mains voltage three-phase alternating current of constant frequency 400 Hz is fed to a combined stator winding 3 (terminals 1A, 1B, 1C) asynchronous-synchronous exciter 2 and the formation of asynchronous starting torque occurs due to the interaction of the rotating flux of the stator generated by currents flowing in the combined winding 3 of the stator, consisting of two parallel-connected three-phase star and rotor flux generated by currents flowing in the circuits devyatietazhnoe cage combined winding 4 of the rotor. Because of the symmetry of the phase windings of the rotor, the voltage at the diodes rotating semiconductor Converter 5 in the starting mode is almost equal to zero (pins 2A, 2B, 2C). Because in the process of starting the synchronous machine 1 is not excited, the vehicle accelerates it to podsyhanii speed is relatively fast. Upon reaching podsyhanii speed excitation of the synchronous machine 1 is carried out through the power winding 3 of the stator of the asynchronous-synchronous exciter 2 through the zero findings 01 and 02 DC from the field controller 6 through the switch of modes 7 and the contacts of the switch 9. Contact the s 9 are closed by the signal of the rotational speed meter 8 of the rotor of the synchronous machine 1. After fulfilling the conditions of self-synchronization anchor chain synchronous machine 1 switch modes 7 through the contacts of switch 11 is connected to an AC three-phase current, simultaneously obestochena power supply circuit, an alternating three-phase current stator winding 3 asynchronous-synchronous exciter 2, opening the contacts of switch 10. When the agent stops running in motor mode and switches to generator mode, providing the current in the excitation winding of the synchronous machine 1.

In the operating mode of the synchronous machine 1 is running its excitation is carried out by the field controller 6, the supply DC zero findings 01 and 02 combined winding 3 of the stator of the asynchronous-synchronous exciter 2 through the switch of modes 7 and the contacts of the switch 9.

Flowing in the combined three-phase, consisting of 3 parallel branches for polarity p2=3 winding 4 of a rotor of the alternating current is rectified rotating semiconductor Converter 5 and is supplied to the excitation winding of the synchronous machine 1, ensuring its stable operation.

The advantage of the proposed device for start-up and brushless excitation contactless synchronous machines through the use of asynchronous-synchronous exciter with combined electric and magnetic circuits is higher is their reliability and simplify the design, the possibility of failure of the semiconductor elements of the Converter during start-up and self-synchronization synchronous machines, eliminating the need for additional windings on the stator and the rotor. As a consequence, improve the use of active materials of the device, increases reliability and simplifies the device itself.

Device for starting and brushless excitation contactless synchronous machine, including the main synchronous machine that converts synchronous exciter main synchronous machine with rotor and stator in a common magnetic system with asynchronous podozritelen made in the form of an induction motor, the field winding synchronous exciter located on the rotor and stator winding, a rotating semiconductor Converter and a field controller, characterized in that it is provided with a switch modes by measuring the rotation frequency of the rotor core of a synchronous machine with input and output, and switches the windings, the latter being made in the form of coil groups in pavlopoulou magnetic system of the stator and the rotor, and the magnetic system is made aligned with the magnetic flows with a smaller number of poles for the motor operation mode and a large number of poles for the generator operation mode, while the coil winding group is a commutator made in the form of dial-up in two parallel-connected three-phase star for inclusion in the motor mode, coil groups rotor winding is made for motor mode devyatietazhnyj short-circuited, and for generating mode - three-phase with three parallel coil groups within each phase, the switch of modes associated with the winding switches to connect the DC to zero conclusions three-phase star in the generator mode of operation and switching of the main synchronous machine on the external network, and measuring the rotation frequency of the rotor core of a synchronous machine with its input connected to the rotor winding of the main synchronous machine and its output is connected to switch modes.



 

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