Excitation system of asynchronized electric machine

FIELD: electricity.

SUBSTANCE: longitudinal excitation winding (1) and transverse excitation winding (2), located on the rotor of the asynchronized machine, are connected in series and fed by a three-phase transformer (3) through two back-to-back three-phase controlled rectifier. The first rectifier is formed by thyristor groups (4) and (5), the second one - by thyristor groups (6) and (7). The rectifiers are controlled by an automatic excitation controller (8), influencing their thyristor groups (4-7). The common point (9) of the windings (1) and (2) is galvanically connected to the neutral (10) of the secondary windings of the transformer (3) by the circuit (11). A rejection filter from parallel inductance (12) and capacitor (13) is introduced in the circuit (11) and is tuned to the third harmonic of the mains frequency. The secondary windings of the transformer (3) are made of semi-windings and are connected in a zigzag.

EFFECT: simplification of the excitation system and reduction of energy losses in its elements.

3 cl, 2 dwg

 



 

Same patents:

FIELD: electricity.

SUBSTANCE: invention relates to electrical engineering and can be used in a shaft generator system. The technical result is providing dynamic prevention of short circuiting. The shaft generator system comprises a shaft generator (18), having an inverter (42) with an intermediate voltage loop, with network-side inductance, wherein the inverter (42) with an intermediate voltage loop has at the generator side and the network side a corresponding alternating current rectifier (44, 46), connected to each other at the dc voltage side. The network-side alternating current rectifier (46) has at least two phase modulators, which respectively have an upper and a lower rectifier branches (P1, N1, P2, N2, P3, N3), which respectively have a plurality of electrically series-connected two-pole subsystems (SM1, SM2, …, SMn), which respectively have a unipolar storage capacitor (CSM), which is electrically parallel-connected to a circuit of series-connected two semiconductor switches (S1, S2) with a corresponding anti-parallel connected diode (D1, D2).

EFFECT: providing a shaft generator system having, as a static frequency converter, an inverter (42) with an intermediate voltage loop, which can be used to maintain the required network reactions and suppress transient operating states.

7 cl, 5 dwg

FIELD: electricity.

SUBSTANCE: in excitation system of synchronous generator, external DC source (11) is connected parallel to inductor (3) via common electronic switch (12). Current converter (13) is connected in series with armature winding (2) and connected to bypass (14) and second rectifier (15). Excitation system includes analogue to digital converter (16), two storage registers (17, 18), pulse distributor (19), stable frequency pulse generator (20), substractor (21), reference register (22), numeric comparator (23), two differentiators (24, 26), RS trigger (25), logic OR element (27), START bus (28), limiting generator (29), inverter (30), logic AND element (31), resistors from first 32-1 to Nth 32-N and section electronic switches from first 33-1 to Nth 33-N. Resistance Ri of resistor 32-i is determined by formula Ri=R1/2(i-1) where R1 is resistance of resistor 32-1.

EFFECT: increased precision of excitation forcing.

1 dwg

FIELD: electricity.

SUBSTANCE: invention is related to a power distribution system and method. The system (10) contains a lot of generating systems (12, 14, 16, 18), at that each generating system (12, 14, 16, 18) contains an alternating current generator (20, 22, 24, 26) coupled directly to the rectifier (28, 30, 32, 34). The alternating current generator (20, 22, 24, 26) with slewing capacity is coupled to the energy source (13, 15, 17, 19). During operation of the energy source (13, 15, 17, 19) the alternating current generator (20, 22, 24, 26) generates an output signal (38, 40, 42, 44) desynchronised in regard to the variety of other generating systems (12, 14, 16, 18) and having a variable velocity. The rectifier (28, 30, 32, 34) coupled directly to the generator (20, 22, 24, 26) is adapted to convert an output signal (38, 40, 42, 44) of the alternating current generator (20, 22, 24, 26) into direct current output signal (46, 48, 50, 52). The direct current distribution bus (36) is connected to direct-current outputs (46, 48, 50, 52) of each rectifier (28, 30, 32, 34). The system (10) contains also a variety of inverters (56, 58, 60, 62) adapted to receive power from the bus (36). The output signal of each inverter (56, 58, 60, 62) is adapted to activate an alternating current motor (64, 66, 68, 70).

EFFECT: improvement of power distribution quality.

15 cl, 4 dwg

FIELD: electricity.

SUBSTANCE: excitation system includes synchronous generator (1) with armature (2) and inducer (3) windings, rectifiers (4), (15), summing transformer (5) with primary current winding (6), primary voltage winding (7), secondary winding (8) and control winding (9) and voltage corrector (10), external DC source (11), electronic key (12), current transformer (13) with shunt (14). System contains analogue-to-digital transformer (16), memory registers (17,18), pulse distributor (19), generator of pulses (20) with stable frequency, substractor (21), decoder (22), clamps (23, 24) for load connection, RS-trigger (25), differentiator (26), logic elements OR (27), AND (31), START bus (28), generator-limiter (29), inverter (30).

EFFECT: expanding functionality providing start-up of cage induction motors comparable to generator in power, improving reliability.

1 dwg

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

FIELD: electricity.

SUBSTANCE: device of electromechanical control includes the second induction motor and the second block of three automatic splitters. The first, second and third outputs of the block from three switchboards are accordingly connected with the first, second and third inputs of the second induction electric motor, rigidly connected to the first induction electric motor, and the first, second and third outputs of the induction generator are accordingly connected to the first, second and third inputs of the second block from three automatic splitters, having the first, second and third outputs of which accordingly connected with the first, second and third inputs of the first block from three automatic splitters, the fourth, fifth and sixth outputs of which are accordingly connected to the first input of the first AC voltage stabiliser, with the second inputs of the first and second AC voltage stabiliser and with the first input of the second AC voltage stabiliser and having a separate input connected to the output of the motor control panel.

EFFECT: increased frequency of electric motor shaft rotation without increase in energy resources consumption.

1 dwg

FIELD: electricity.

SUBSTANCE: voltage multiplier, toroidal potentiometer, drive, a unit of two automatic circuit-breakers and commutation switch are introduced into elecrtromechanical control device; at that output of three-phase rectifier is connected to the first input of the automatic circuit-breaker having an output connected to the first input of the unit of two automatic circuit-breakers having the second output and the first and second inputs connected respectively through toroidal potentiometer, through voltage multiplier to the above output of the automatic circuit-breaker, through commutation switch to input of the electric motor, to input of the drive connected rigidly to toroidal potentiometer.

EFFECT: automatic voltage control without bulkiness of the device, increasing economy of power resources.

1 dwg

FIELD: electricity.

SUBSTANCE: voltage multiplier, potentiometer and commutation switch are introduced into the electromechanical control device; at that output of the three-phase rectifier is connected through voltage multiplier, potentiometer and commutation switch to the input of automatic circuit-breaker.

EFFECT: increasing economy of power resources.

1 dwg

FIELD: electrical engineering.

SUBSTANCE: device for magnetic field killing when the synchronous machine excitation winding is disconnected from the power supply contains a switching apparatus (1), placed in parallel to the power supply (2) and the excitation winding (3); connected parallel to the said winding is a circuit consisting of an active resistance (4) and a circuit, placed in parallel; the latter circuit contains two thyristors (5, 6) or a thyristor and a diode, parallel and back-to-back. The device also contains a circuit with low resistance represented by or placed parallel to the circuit excitation winding containing a control key (7) or connected parallel to the active resistance (4) of the circuit containing a diode or thyristor (8) and a capacitor (9), serially placed; connected parallel to the capacitor is a discharge resistor (10).

EFFECT: ensuring the possibility of the switching apparatus application without increase of switching properties with magnetic field efficiently killed.

5 dwg

FIELD: electrical engineering.

SUBSTANCE: device contains a synchronous generator with stator and excitation windings, a rectifier connected to the stator winding, a voltage sensor connected to the rectifier output pins, a voltage setting device, a control circuit and a device for rigid negative feedback; included in the control circuit are additional connected element: a comparison unit, a regulating device, a key element, a reverse diode; additionally introduced are a sensor of excitation current in the excitation winding circuit, a device for isodromic (flexible) negative feedback; functionally. The device is intended for transmission of excitation current oscillations as may occur from the excitation current sensor output to the third input of the comparison unit without phase shift.

EFFECT: damping excitation current self-oscillations and fast quench of the generator output voltage LF modulation.

2 cl, 1 dwg

FIELD: electricity.

SUBSTANCE: method of control of the wind-driven power plant containing the generator (1) with the stator (2), the inductor (4), at least, with two poles (6) of the rotor, each with the pole winding (32, 42) for generation of the magnetic field induced in the respective pole (6) of the rotor, and the air gap (8) between the stator (2) and the inductor (4), includes the following steps: control, respectively, of excitement current through each of pole windings (32, 42); change of, at least, one of excitement currents, at least, in relation to one of other excitement currents and/or change of, at least, one of excitement currents depending on the position of the inductor (4) with reference to the stator (2).

EFFECT: weight decrease and improvement of ratio between the weight and rated power of the generator.

15 cl, 9 dwg

FIELD: electricity.

SUBSTANCE: in excitation system of synchronous generator, external DC source (11) is connected parallel to inductor (3) via common electronic switch (12). Current converter (13) is connected in series with armature winding (2) and connected to bypass (14) and second rectifier (15). Excitation system includes analogue to digital converter (16), two storage registers (17, 18), pulse distributor (19), stable frequency pulse generator (20), substractor (21), reference register (22), numeric comparator (23), two differentiators (24, 26), RS trigger (25), logic OR element (27), START bus (28), limiting generator (29), inverter (30), logic AND element (31), resistors from first 32-1 to Nth 32-N and section electronic switches from first 33-1 to Nth 33-N. Resistance Ri of resistor 32-i is determined by formula Ri=R1/2(i-1) where R1 is resistance of resistor 32-1.

EFFECT: increased precision of excitation forcing.

1 dwg

FIELD: electricity.

SUBSTANCE: excitation system includes synchronous generator (1) with armature (2) and inducer (3) windings, rectifiers (4), (15), summing transformer (5) with primary current winding (6), primary voltage winding (7), secondary winding (8) and control winding (9) and voltage corrector (10), external DC source (11), electronic key (12), current transformer (13) with shunt (14). System contains analogue-to-digital transformer (16), memory registers (17,18), pulse distributor (19), generator of pulses (20) with stable frequency, substractor (21), decoder (22), clamps (23, 24) for load connection, RS-trigger (25), differentiator (26), logic elements OR (27), AND (31), START bus (28), generator-limiter (29), inverter (30).

EFFECT: expanding functionality providing start-up of cage induction motors comparable to generator in power, improving reliability.

1 dwg

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

FIELD: electricity.

SUBSTANCE: device of electromechanical control includes the second induction motor and the second block of three automatic splitters. The first, second and third outputs of the block from three switchboards are accordingly connected with the first, second and third inputs of the second induction electric motor, rigidly connected to the first induction electric motor, and the first, second and third outputs of the induction generator are accordingly connected to the first, second and third inputs of the second block from three automatic splitters, having the first, second and third outputs of which accordingly connected with the first, second and third inputs of the first block from three automatic splitters, the fourth, fifth and sixth outputs of which are accordingly connected to the first input of the first AC voltage stabiliser, with the second inputs of the first and second AC voltage stabiliser and with the first input of the second AC voltage stabiliser and having a separate input connected to the output of the motor control panel.

EFFECT: increased frequency of electric motor shaft rotation without increase in energy resources consumption.

1 dwg

FIELD: electricity.

SUBSTANCE: parameters of exciting regulator are set against deviation of setup of one of its output signals; initial value of parameters optimisation criterion for regulator is E0, a new value of parameters optimisation criterion for the regulator is calculated in compliance with formula; setup of the regulated output signal is changed by constant value for fixed time; scale and duration of transient process for the generator output signal is measured against the specified changed setup, new value of parameters optimisation criterion for the regulator E is calculated in compliance with formula and value E0 and value of the parameter are set so that conditions E<E0 is met or the following conditions are met: E≥E0 and (E-E0)/c>βi set E0=E and the parameter is not changed. Otherwise the parameter is set to initial value. The above operations are repeated for other parameters subjected to regulation till average rate of E0 values is changed up to the preset value, where βi is a random value distributed evenly within the range [0.1], c is a positive permanent value that determines rate of optimisation for the regulator parameters.

EFFECT: automatic optimisation of parameters for exciting regulator of synchronous generator at stage of its input into operation without destabilising influence on the power system and loss of its stability.

1 dwg

FIELD: electricity.

SUBSTANCE: voltage multiplier, toroidal potentiometer, drive, a unit of two automatic circuit-breakers and commutation switch are introduced into elecrtromechanical control device; at that output of three-phase rectifier is connected to the first input of the automatic circuit-breaker having an output connected to the first input of the unit of two automatic circuit-breakers having the second output and the first and second inputs connected respectively through toroidal potentiometer, through voltage multiplier to the above output of the automatic circuit-breaker, through commutation switch to input of the electric motor, to input of the drive connected rigidly to toroidal potentiometer.

EFFECT: automatic voltage control without bulkiness of the device, increasing economy of power resources.

1 dwg

FIELD: electricity.

SUBSTANCE: voltage multiplier, potentiometer and commutation switch are introduced into the electromechanical control device; at that output of the three-phase rectifier is connected through voltage multiplier, potentiometer and commutation switch to the input of automatic circuit-breaker.

EFFECT: increasing economy of power resources.

1 dwg

FIELD: electricity.

SUBSTANCE: invention relates to the field of electrical engineering and may be used in electric machines for control of excitation of synchronous generators applied in autonomous sources of electric energy. The technical result is expansion of functional possibilities. The excitation system comprises a synchronous generator (1), a winding of an anchor (2) and an inductor (3), the first rectifier (4), the summing transformer (5) with the primary current (6) winding and the primary voltage winding (7), the secondary (8) winding and the control winding (9), a voltage corrector (10), an outer source of DC current (11), an electronic key (12), a current transformer (13) with a shunt (14) and the second rectifier (15), an analog to digital converter (16), the first (17) and the second (18) registers of memory, a pulse distributor (19), a pulse generator (20) of stable frequency, a subtractor (21), a setting register (22), a numerical comparator (23), the first differentiator (24), an RS-trigger (25), the second differentiator (26), a logical OR element (27), a START bus (28), a shaper-limiter (29), an inverter (30) and a logical AND element (31).

EFFECT: system of excitation provides for start-up of induction motors with a short-circuited rotor comparable in capacity to a generator.

1 dwg

FIELD: electricity.

SUBSTANCE: in the self-excitation generator 1 containing an automatic voltage regulator 10 the phase-advance protection device contains: magnetisation current control shaper 21 (serially connected to the magnetised winding 6 and switched over to the open and closed position with control circuit 23 ARN 10 for supply of magnetisation current to the magnetised winding 6), a shaper of rotor short-circuit for phase-advance load 22 protection (connected in parallel to the magnetised winding and supplying short circuit current to the magnetised winding 6 when switched over to the open position) and a compensatory feedback circuit 30 connected as the power supply source of the magnetisation current control shaper and the shaper of rotor short-circuit for phase-advance load protection; the compensatory feedback circuit 30 contains a capacitor 32 where charge is accumulated while the magnetisation current control shaper 21 is in the open position.

EFFECT: building a device for phase-advance load protection using inexpensive elements.

4 cl, 7 dwg

FIELD: electric engineering.

SUBSTANCE: method includes measuring voltage, generator current, and current alternation parameters, which current is fed from excitation system dependently on these parameters, rotor voltage control, comparison of it to constraint and if it is exceeded - enabling discharge circuit, method additionally includes controlling current in discharge circuit of generator rotor and if current appears in this circuit current fed from excitation system is decreased.

EFFECT: higher reliability, lower costs, broader functional capabilities.

4 dwg

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