Quasi saturation reactor flexibly starting high voltage motor device
Technical field
Quasi saturation reactor flexibly starting high voltage motor device of the present invention belongs to field of power electronics, and it is at flexibly starting high voltage motor.
Background technology
From the principle, quasi saturation reactor soft starter device is a kind of improved form of switch transformer soft starter device.It is compared with existing switch transformer soft starter device, and sizable change is arranged on design concept.
The switch transformer soft start is developed by the thyristor soft start.The both exchanges pressure regulation by the thyristor under phased to realize for the control of soft of high-tension motor.Different is, the latter's thyristor directly is connected in the high-tension circuit, and the former thyristor is connected in the secondary side winding of a step-down switching transformer (during conducting with the secondary side winding short circuit).Because thyristor can not bear too high voltage, the fail safe of operation has had more practical assurance.
For the high-tension motor of 6 kilovolts and 10 kilovolts, thyristor in the thyristor soft starter device must a plurality of series connection just can bear high pressure, although present thyristor manufacture level improves a lot, for the flexibly starting high voltage motor of 6 kilovolts and 10 kilovolts, high-pressure thyristor still needs 3 to 5 series connection to use, and series connection will inevitably bring the technical barrier of all pressing.And in the switch transformer soft starter device, the series connection of thyristor is used and just can be avoided.This is the technical advantage of switch transformer soft starter device.The cost of switch transformer is more than 50% of whole device in the switch transformer soft starter device, and the weight of switch transformer is more than 80% of whole device.The increase of cost and weight is the obvious shortcoming of such flexibly starting high voltage motor device.
The circuit diagram of present existing switch transformer soft starter device as shown in Figure 1, in Fig. 1, QF1, QF2 are vacuum circuit-breaker or contactor, T is a switch transformer, SCR is a thyristor, M is a high-tension motor.
The switch transformer soft starter device is composed as follows: each 1 of inlet wire and bypass high-pressure vacuum contactor (or vacuum circuit-breaker), and 1 of switch transformer, anti-parallel thyristor 3 is to (or 3n to).The first side winding of switch transformer is connected in the high-tension motor loop, and secondary side winding is by phased thyristor short circuit.The load of general transformer all is to be connected on the secondary side of transformer, and the load of the switch transformer in the soft start is the high-tension motor that is in series with its first side winding, and the equivalent reactance of first side winding can change down at the phased of thyristor.Therefore, the switch transformer soft starter device is (metering function) Regulatable reactor soft starter device again.Should, back one call is proper more.
Although be called Regulatable reactor, it still has primary side and secondary side winding, and its regulating action still relies on the thyristor phase shifting control of secondary side winding.So these two kinds of soft starter devices only are that call is inequality, between there is no any substantial difference.
In order to ensure the wide tuning range of switch transformer or Regulatable reactor soft starter device starting current, these two kinds of soft starter devices are all made the conventional electric power transformer that rated voltage and line voltage (being the motor rated voltage) are equal to switch transformer.Claim in patent of invention 200910071950 " the switch auto-transformer type mesohigh motor soft start device " lining that Harbin Pa Teer electric corporation is declared: " the motor starting electric current is adjustable continuously in the motor total head directly plays 0 ~ 100% scope of electric current." the words shows that the rated voltage and the line voltage of switch transformer are equal to.[press: the definition of " the motor total head directly plays electric current " is the motor total head electric current under the rotor stall condition, and this electric current generally is 5 ~ 7 times of rated current].
As previously mentioned, switch transformer or Regulatable reactor soft starter device have brought the complicated of device: the weight, volume and the manufacturing cost that have increased equipment greatly when successfully having avoided the withstand voltage difficult problem of thyristor.In order to reduce them, the manufacturing firm that has makes oil immersed type to switch transformer, and that oil immersion has brought is safe, the new problem of safeguarding the aspect; The manufacturing firm that has makes auto-transformer type to switch transformer, and self coupling has to thyristor has been placed in the high-tension circuit.
The present patent application people Gao Yuenong quasi saturation notion that takes the lead in proposing and having set forth in its monograph " controllable transducer principle, design with use " (Chinese Water Conservancy water power publishing house 2008.1) lining: " quasi saturation is soft start with a kind of characteristics that saturable reactor had; it can make saturable reactor when being zero, flow through bigger alternating current at the DC control electric current ".(11-5 joint--178-9 page or leaf).The quasi saturation reactor is exactly the soft start reactor according to this conceptual design.It can circulate in harmful as the electrical device of transmission of electric energy and in soft start useful quasi saturation electric current.
So-called quasi saturation electric current is exactly the sizable electric current that flows through reactor first side winding and high-tension motor when total head and thyristor do not trigger in the soft start of quasi saturation reactor.
The characteristics of quasi saturation reactor are:
1), it is the conventional electric power transformer that rated voltage is significantly less than the electrical network rated voltage, is the conventional electric power transformer of the unconventional use of connecting with load motor.
2), for identical starting object, the rated voltage of quasi saturation reactor is 50 ~ 60% of corresponding switch transformer or a Regulatable reactor rated voltage.
3), the cost of quasi saturation reactor soft starter device and weight have 20% and 30% reduce than switch transformer soft starter device or Regulatable reactor soft starter device respectively.
In today that Electric Traction is maximized day by day, flexibly starting high voltage motor is a growing demand.Quasi saturation reactor flexibly starting high voltage motor belongs to soft start solid-state, non-frequency.
The soft start of high-tension motor liquid resistance is low with cost, the hierarchy of skill is low, heavy, be not easy to be maintained as principal character, the impetus in the high pressure soft start market of progressively fading out has been arranged.
Variable frequency soft start is good with starting performance, and is with high content of technology, and cost exceeds far away, and the maintenance requirement height is a principal character, makes first appearance on high pressure soft start market, and the existing market occupation rate is low.
All things considered, soft start solid-state, non-frequency are the main products on the current high pressure soft start market.In this classification, exist
Thyristor (phased) soft start,
Switch transformer (phased) soft start (perhaps Regulatable reactor soft start),
The such 3 kinds of major products of magnetic control (core saturation control) soft start.Quasi saturation reactor flexibly starting high voltage motor belongs to
Switch transformer (phased) soft start (perhaps Regulatable reactor soft start) is the new product that therefrom breeds out.
Thyristor (phased) soft start and
The main circuit connection figure of the soft start of these two kinds of forms of magnetic control (core saturation increases magnetic control system) soft start is illustrated respectively in Fig. 2 and Fig. 3.
[annotate: the quasi saturation soft start and the magnetic controlled soft starter of high-tension motor have all utilized quasi saturation, and still, they have the difference of essence, and the former control magnetic of borrowing realizes, and the latter's control borrow increase the magnetic realization].
Summary of the invention
The technical problem to be solved in the present invention provides a kind of quasi saturation reactor flexibly starting high voltage motor device.
In order to solve the problems of the technologies described above, the invention provides a kind of quasi saturation reactor flexibly starting high voltage motor device, comprise high voltage isolator QS, as the QF1 of vacuum contactor or vacuum circuit-breaker, QF2, high-tension motor M and reactor as vacuum contactor or vacuum circuit-breaker, the reactor saturable reactor that is as the criterion.
Improvement as quasi saturation reactor flexibly starting high voltage motor device of the present invention: the quasi saturation reactor comprises first side winding A1A2, B1B2, the C1C2 of three stem stem three-phase reactors, the secondary side winding a1a2 of three stem stem three-phase reactors, b1b2, c1c2,3 cover anti-parallel thyristor assemblies, every cover anti-parallel thyristor assembly is made up of two antiparallel thyristors;
The secondary side winding a1a2 of three stem stem three-phase reactors, b1b2, c1c2 link to each other with a cover anti-parallel thyristor assembly separately respectively and form the closed-loop path; The secondary side winding a1a2 of three stem stem three-phase reactors, b1b2, c1c2 is for isolating, connect into triangle mutually or connecting into star.
Further improvement as quasi saturation reactor flexibly starting high voltage motor device of the present invention: 3 cover anti-parallel thyristor assemblies are respectively: the anti-parallel thyristor assembly that the anti-parallel thyristor assembly that the anti-parallel thyristor assembly that antiparallel thyristor SCR1 and SCR4 form, antiparallel thyristor SCR3 and SCR6 form, antiparallel thyristor SCR2 and SCR5 form;
Three phase network is connected in series to high-tension motor M through first side winding A1A2, the B1B2, the C1C2 that drive contact and quasi saturation reactor of high voltage isolator QS and vacuum contactor QF1;
First side winding A1A2, the B1B2, the C1C2 that drive contact and quasi saturation reactor of vacuum contactor QF2 are connected in parallel;
The secondary side winding a1a2 of quasi saturation reactor, b1b2, c1c2 are connected in parallel with antiparallel thyristor SCR1 and SCR4, antiparallel SCR3 and SCR6 and antiparallel SCR5 and SCR2 respectively;
The first side winding A1A2 of quasi saturation reactor, B1B2 and C1C2 be respectively three stem stem three-phase reactor A mutually, B mutually and the leading-out terminal of C first side winding mutually; The secondary side winding a1a2 of three stem stem three-phase reactors, b1b2 and c1c2 be respectively three stem stem three-phase reactor A mutually, B mutually and the leading-out terminal of C secondary side winding mutually; Described A1 and a1 are end of the same name, and B1 and b1 are end of the same name, and C1 and c1 are end of the same name;
The secondary side winding a1a2 of three stem stem three-phase reactors, b1b2, c1c2 isolates mutually.
In the present invention, every employing switch transformer soft starter device, perhaps Regulatable reactor soft starter device, the perhaps flexibly starting high voltage motor device of other any other call, as long as the minimum value of the continuous adjustable extent of motor current greater than 50% motor rated current, all belongs to the soft start of quasi saturation reactor.
Below, discuss the present invention in detail:
1, the present invention has affirmed the feasibility of quasi saturation reactor soft start:
After the basic ideas of patent of the present invention formed, patent applicant of the present invention had carried out simulation study and prototype test.
Prototype test for the soft start of quasi saturation transformer shows that the soft start of quasi saturation transformer can be got up the test blower fan fully smoothly.The quasi saturation transformer primary side of real scene shooting in Soft Start-up Process and secondary side current waveform (as shown in Figure 6) clearly illustrate out with the Current Waveform Characteristics of quasi saturation soft start.
The result of simulation study and prototype test shows that the quasi saturation soft start does not have impassable technology barrier: it can not cause that circuit disturbs or the increase of ' voltage glitch ', can not cause the out of control of additional vibration and system, can not cause too big noise.In other words, the soft start of quasi saturation reactor is feasible.
2, the invention provides the method for designing of quasi saturation reactor soft starter device: comprise the rated primary voltage how to choose the quasi saturation reactor and the voltage ratio of primary side and secondary side, how to choose primary side and secondary side current, how to choose model of thyristor or the like.
3, the quasi saturation electric current must with mistake:
Many benefits that the quasi saturation electric current brings are as above-mentioned.
But, sizable quasi saturation electric current still can bring some negative effects.It has dwindled the adjustable extent of motor current in the flexible starter for electric motor.The primary side current of power transformer can be regulated by its secondary side current.The primary side current adjustable extent of conventional electric power transformer can be started from scratch toward adjusted, and the primary side current adjustable extent of quasi saturation transformer then is merely able to begin toward adjusted from the quasi saturation electric current.Corresponding therewith, the starting electromagnetic torque of quasi saturation transformer soft start also has one greater than zero initial value, can not start from scratch.
Someone worries that the starting electromagnetic torque can not be started from scratch and can be sacrificed the mild property of soft start, can cause damage to motor and the plant equipment that is dragged.
This worry is unnecessary.Analyze easily theoretically and reach a conclusion, so-called mechanical shock only is below 10 % of total head across-the-line starting.
Practice should have bigger convincingness.Move towards more than 400 the high-tension motor magnetic control soft starter in market from the Xiandao Bell Electric Co., Ltd, Tianjin, all according to the design of quasi saturation thought, the initial current of motor is all at more than 200% of rated current.Practice over 8 years shows that the mechanical shock that the quasi saturation electric current causes is inappreciable.
4, the size of quasi saturation electric current depends on the number of turn of transformer first side winding:
Simulation calculation for quasi saturation reactor soft starter device shows that the size of quasi saturation electric current only depends on the number of turn of transformer first side winding under the certain condition of iron core parameter, and the number of turn is few more, quasi saturation electric current big more (with reference to Fig. 5).
5, quasi saturation reactor flexibly starting high voltage motor device of the present invention has the public advantage of solid-state non-frequency soft starter device.For example, carry out the closed-loop control of multiple menu, have thorough protection, telecommunication or the like.
Description of drawings
Below in conjunction with accompanying drawing the specific embodiment of the present invention is described in further detail.
Fig. 1 is the main circuit diagram of present existing switch transformer soft starter device;
Fig. 2 is present existing thyristor soft start main circuit connection figure;
Fig. 3 is present existing magnetic controlled soft starter main circuit connection figure;
Fig. 4 is the main wiring diagram of quasi saturation reactor soft starter device of the present invention;
Fig. 5 is the graph of a relation of the quasi saturation electric current (ordinate) and the quasi saturation reactor first side winding number of turn (abscissa);
Fig. 6 is quasi saturation reactor primary side and a secondary side simulated current waveform in the soft start of quasi saturation reactor;
Among Fig. 6: waveform 1 expression actual measurement primary side current, waveform 2 expression actual measurement secondary side currents;
Fig. 7 is that the soft start of quasi saturation reactor is with reference to winding diagram (that is, being the actual user mode figure of Fig. 4).
Embodiment
Embodiment 1, a kind of quasi saturation reactor flexibly starting high voltage motor device, as shown in Figure 4, comprise high voltage isolator QS, vacuum contactor (or vacuum circuit-breaker) QF1, vacuum contactor (or vacuum circuit-breaker) QF2, high-tension motor M and quasi saturation reactor.The quasi saturation reactor comprises first side winding A1A2, B1B2, the C1C2 of three stem stem three-phase reactors, the secondary side winding a1a2 of three stem stem three-phase reactors, b1b2, c1c2,3 cover anti-parallel thyristor assemblies, every cover anti-parallel thyristor assembly is made up of two antiparallel thyristors; That is, 3 cover anti-parallel thyristor assemblies are respectively: the anti-parallel thyristor assembly that the anti-parallel thyristor assembly that the anti-parallel thyristor assembly that antiparallel thyristor SCR1 and SCR4 form, antiparallel thyristor SCR3 and SCR6 form, antiparallel thyristor SCR2 and SCR5 form.
Concrete annexation is as follows:
1, three phase network is connected in series to high-tension motor M through first side winding A1A2, the B1B2, the C1C2 that drive contact and quasi saturation reactor of high voltage isolator QS and vacuum contactor QF1.
2, first side winding A1A2, the B1B2, the C1C2 that drive contact and quasi saturation reactor of vacuum contactor QF2 are connected in parallel.
3, the secondary side winding a1a2 of quasi saturation reactor, b1b2, c1c2 and antiparallel thyristor SCR1 and SCR4(SCR3 and SCR6, SCR5 and SCR2) be connected in parallel.All lines are finished by the three-core cable line.
4, A1A2(B1B2, C1C2) be the leading-out terminal of the first side winding of three stem stem three-phase reactor A phases, a1a2(b1b2 c1c2) is the leading-out terminal of the secondary side winding of three stem stem three-phase reactor A phases.Wherein A1 and a1(B1 and b1, C1 and c1) be end of the same name.
5, the secondary side winding a1a2 of three core-column three-phase transformers, b1b2, c1c2 isolate mutually.
During the actual use of above-mentioned quasi saturation reactor flexibly starting high voltage motor device, as shown in Figure 7:
Concrete annexation is as follows:
1, three phase network is connected in series to high-tension motor M through first side winding A1A2, the B1B2, the C1C2 that drive contact and quasi saturation reactor of high voltage isolator QS and vacuum contactor QF1.
2, first side winding A1A2, the B1B2, the C1C2 that drive contact and quasi saturation reactor of vacuum contactor QF2 are connected in parallel.
3, the secondary side winding a1a2 of quasi saturation reactor, b1b2, c1c2 and antiparallel thyristor SCR1 and SCR4(SCR3 and SCR6, SCR5 and SCR2) be connected in parallel.All lines are finished by the three-core cable line.
4, A1A2(B1B2, C1C2) be the leading-out terminal of the first side winding of three stem stem three-phase reactor A phases, a1a2(b1b2 c1c2) is the leading-out terminal of the secondary side winding of three stem stem three-phase reactor A phases.Wherein A1 and a1(B1 and b1, C1 and c1) be end of the same name.
5, the secondary side winding a1a2 of three core-column three-phase transformers, b1b2, c1c2 isolate mutually.
6, antiparallel thyristor is assembled in respectively on separately the same radiator.What be in parallel with it has RC capacitance-resistance and an overvoltage absorption plant.
7, the outgoing cable line is connected to 1 ~ 3 voltage transformer between high voltage isolator QS and vacuum contactor QF1, at the inlet wire of motor M 2 or 3 current transformers of having connected.Their output all is connected to control system C.S.
8, the trigger impulse through isolating that produces from control system C.S is connected to the trigger electrode of antiparallel thyristor (SCR1 and SCR4, SCR3 and SCR6, SCR5 and SCR2) according to phase sequence.
9, the DC power supply that needs of control system C.S from the workshop 380 volts of power supplys obtain.
High-tension motor quasi saturation reactor Soft Start-up Process (with reference to Fig. 7) is summarized as follows: high voltage isolator QS closure, soft start ' initiation command ' makes vacuum contactor QF1 closure, sizable quasi saturation electric current gives high-tension motor M with the initial start torque from high-tension motor M circulation.Under the adjusting of apparatus control system C.S, thyristor (every cover anti-parallel thyristor assembly) the SCR secondary side current that circulates, after converting primary side and adding on original quasi saturation electric current, make high-tension motor M obtain enough big electric current and be enough to electromagnetic torque that rotor is rotated.Under the continuous action of this electromagnetic torque, the continuous raising speed of high-tension motor M, high-tension motor M back-emf increases thereupon, under the influence of this back-emf, the electric current of high-tension motor can reduce to some extent, after current transformer CT in the device detects, secondary side current is increased, keep the current constant of quasi saturation reactor first side winding by phased (being the phase shifting control of thyristor) for thyristor SCR.High-tension motor M is remained bigger acceleration.By the time start successfully (rotating speed rises to rated speed), high-tension motor M electric current is reduced to below the motor rated current naturally, after apparatus control system C.S detects affirmation by current transformer, and vacuum contactor QF2 closure.Soft start is finished.
Embodiment 2, a kind of quasi saturation reactor flexibly starting high voltage motor device, only with the secondary side winding a1a2 of three core-column three-phase transformers, b1b2, c1c2 connects into triangle by mutual isolation instead, even a2 is connected with b1, b2 is connected with c1, c2 is connected with a1; All the other are with embodiment 1.
Action is with embodiment 1.
Embodiment 3, a kind of quasi saturation reactor flexibly starting high voltage motor device, only with the secondary side winding a1a2 of three core-column three-phase transformers, b1b2, c1c2 makes Y-connection into by mutual isolation, that is, and a2, b2,3 connections of c2.
Action is with embodiment 1.
At last, it is also to be noted that what more than enumerate only is several specific embodiments of the present invention.Obviously, the invention is not restricted to above embodiment, many distortion can also be arranged.All distortion that those of ordinary skill in the art can directly derive or associate from content disclosed by the invention all should be thought protection scope of the present invention.