CN204967281U

CN204967281U - Electric energy load balancing device

Info

Publication number: CN204967281U
Application number: CN201520519661.5U
Authority: CN
Inventors: ***; 潘增先; 汤中义
Original assignee: Sichuan Meibang Electric Co Ltd
Current assignee: Sichuan Meibang Electric Co Ltd
Priority date: 2015-07-17
Filing date: 2015-07-17
Publication date: 2016-01-13
Anticipated expiration: 2025-07-17

Abstract

The utility model discloses an electric energy load balancing device, including the controller, the circuit breaker is established ties and is provided electric current signal input's three current transformer with the circuit breaker, and the electric power equalizer of establishing ties behind current transformer is connected respectively in two ac contactor of electric power equalizer input and output to and the three ac contactor of parallelly connected setting between the electric power equalizer and the neutral conductor, the controller still inserts voltage signal through the output of electric power equalizer. The utility model discloses a current transformer acquires the current signal of three -phase alternating current input, through the voltage signal who detects the load end, carry out the matched pair than balanced to power supply electric energy index, then in feeding back electric power equalizer and corresponding each circuit by the coil electromagnetic control mode that the controller passes through ac contactor with balanced result, thereby the electric energy between having guaranteed respectively to look at and appraise is balanced, and then the power output parameter has been optimized, improve the power supply performance, the stability of distribution transformer end and the safety of consumer have been ensured.

Description

A kind of electric power loads bascule

Technical field

The utility model relates to electrical equipment technical field, specifically, relates to a kind of electric power loads bascule.

Background technology

The city dweller of low voltage three-phase four-wire system with in rural power grids electric power system: because electricity consumer mostly is single-phase load or single-phase mixed with three-phase load, and payload is different and the difference of electricity consumption time.So three alternate unsymmetrical currents are objective reality in electrical network, and this electricity consumption unbalance condition irregularities, also cannot predict in advance.Result in the secular disequilibrium of low-voltage power supply system threephase load.Unsymmetrical current in electrical network can increase the copper loss of circuit and transformer, also can increase the iron loss of transformer, and reducing exerting oneself of transformer even can affect the safe operation of transformer, and finally feedback aggravates the imbalance of three-phase voltage again.Moreover, three-phase imbalance also can cause many harm to electrical network and power consumption equipment:

The first increases the electric energy loss of circuit.In three-phase four-wire power supply network, when electric current is by line conductor, electric energy loss will be produced because there is impedance, its loss and square to be directly proportional by electric current.When low voltage electric network is with three-phase four-wire power supply, owing to there being single-phase load to exist, cause threephase load imbalance unavoidable.When threephase load unbalanced operation, namely the neutral line has electric current to pass through.So not only phase line is lossy, and the neutral line also produces loss, thus adds the loss of power network line.

It two is increase the electric energy loss of distribution transformer.Distribution transformer is the power supply main equipment of low voltage electric network, when it runs under the uneven operating mode of threephase load, will cause the increase of distribution loss.Because the power loss of distribution transforming changes with the degree of unbalance of load.

It three is that distribution transforming is exerted oneself minimizing.During distribution transforming design, its winding construction is by the design of load balance operating condition, and its winding performance is basically identical, and each phase rated capacity is equal.Distribution transforming maximum allows to exert oneself and will be subject to the restriction of every phase rated capacity.If run under distribution transforming is in the uneven operating mode of threephase load, the light phase of load just has spare capacity, thus makes the minimizing of exerting oneself of distribution transforming.Its minimizing degree of exerting oneself is relevant with the degree of unbalance of threephase load.Threephase load imbalance is larger, distribution transforming exert oneself reduce more.For this reason, distribution transforming runs when threephase load is uneven, and its capacity exported just cannot reach rated value, and its reserve capacity is corresponding minimizing also, and overload capacity also reduces.If distribution transforming runs under overload conditions, namely very easily cause distribution transforming heating, time serious, even can cause distribution transforming scaling loss.

Its four be distribution transforming produce zero-sequence current.Distribution transforming runs under the uneven operating mode of threephase load, and will produce zero-sequence current, this electric current will change with the unbalanced degree of threephase load, and degree of unbalance is larger, then zero-sequence current is also larger.If operating distribution transforming exists zero-sequence current, then zero sequence fluxes will be produced in its iron core.(high-pressure side does not have zero-sequence current) this force zero sequence fluxes can only pass through using oil tank wall and steel beam column as passage, and the permeability of steel beam column is lower, when zero-sequence current is by steel beam column, namely to produce magnetic hysteresis and eddy current loss, thus the rising of the steel beam column local temperature of distribution transforming is even generated heat.The winding insulation of distribution transforming also may be accelerated aging because of overheated, cause reduce equipment life.Meanwhile, the existence of zero-sequence current also can increase the loss of distribution transforming.

It five is the safe operations affecting power consumption equipment.Distribution transforming is according to threephase load balance movement operating condition design, and the resistance of its every phase winding, leakage reactance and exciting impedance are basically identical.When distribution transforming runs when threephase load balances, its three-phase current is substantially equal, and the inner every phase pressure drop of distribution transforming is also substantially identical, then the three-phase voltage that distribution transforming exports also is balance.

It six is reduce load motor efficiency.Distribution transforming runs under the uneven operating mode of threephase load, will cause output voltage three-phase imbalance.Because unbalance voltage also exists positive sequence, negative phase-sequence, zero sequence three component of voltages, when after this unbalanced voltage input motor, it is contrary with the rotating magnetic field that positive sequence voltage produces that negative sequence voltage produces rotating magnetic field, plays braking action.But because positive sequence magnetic field is more much better than than negative sequence field, motor still rotates by positive sequence magnetic direction.And due to the braking action of negative sequence field, output power of motor will be caused to reduce, thus cause motor efficiency to reduce.Meanwhile, the temperature rise of motor and reactive loss, also increase the degree of unbalance with three-phase voltage.So motor runs under imbalance of three-phase voltage situation, be very uneconomical and unsafe.

Utility model content

For overcoming the problems of the prior art, the utility model provides a kind of can balance the electric power loads bascule controlling three-phase output voltage, reduce line loss.

To achieve these goals, the technical solution adopted in the utility model is as follows:

A kind of electric power loads bascule, comprise the controller U1 with pin, be connected to the circuit breaker Q F of three-phase alternating current energization input, connect with circuit breaker Q F in each phase respectively and be connected the current transformer TA1 thinking that controller U1 provides current signal to input with the pin of controller U1, TA2 and TA3, at current transformer TA1, after TA2 and TA3, series connection access three-phase alternating current is to the power balance device U2 of the supply line of load, be connected to power balance device U2 and three current transformer TA1, TA2, A.C. contactor KM4 between TA3, be connected to the A.C. contactor KM5 between power balance device U2 and load, with connect after A.C. contactor KM4, the A.C. contactor KM6 of power balance device U2 and A.C. contactor KM5 parallel connection, and the A.C. contactor KM1 be arranged in parallel between three input contacts of three-phase and neutral line N is mated at power balance device U2, KM2 and KM3, wherein, the pin of described controller U1 is by six A.C. contactor KM1 in parallel, KM2, KM3, KM4, KM5, the coil of KM6 connects neutral line N, the pin of controller U1 accesses voltage signal by the output of power balance device U2.

Particularly, the pin of described controller U1 totally 16, the wherein coil of 6 connection A.C. contactors KM1, KM2, KM3, KM4, KM5, KM6,4 for accessing current signal, 4 for accessing voltage signal, one in all the other 2 is connected between current transformer TA3 and circuit breaker Q F, and one is directly connected with neutral line N, for obtaining power supply.

Compared with prior art, the utility model has following beneficial effect:

The utility model obtains the current signal of three-phase alternating current input by current transformer, by detecting the voltage signal of load end, coupling contrast is carried out to power supply power index balanced, then by controller, equilibrium result is fed back in power balance device and corresponding each circuit by the coil electromagnetism control mode of A.C. contactor, thus ensure that the electric energy balance between each phase, and then optimize electric power output parameter, improve power supply performance, ensure that the safety of the stable of distribution transformer end and power consumption equipment, and the utility model design is ingenious, compact, easy to use, be easy to manufacture, with low cost, be with a wide range of applications, be applicable to applying.

Accompanying drawing explanation

Fig. 1 is circuit theory diagrams of the present utility model.

Embodiment

Below in conjunction with drawings and Examples, the utility model is described in further detail, and execution mode of the present utility model includes but not limited to the following example.

Embodiment

As shown in Figure 1, this electric power loads bascule, primarily of the controller U1 in access three-phase alternating current supply line and power balance device U2, and form for current transformer TA1, TA2, TA3 of detecting and A.C. contactor KM1, KM2, KM3, KM4, KM5, KM6 for controlling.It is as follows that it specifically forms structure:

Described controller U1 adopts the control chip of integrated form, has 1 ~ 16 pin.It is in the supply line of load supplying that described current transformer and power balance device U2 are connected on three-phase alternating current successively, arranges circuit breaker Q F ensure access Electrical Safety at the incoming end of three-phase alternating current; At the input series AC contactor KM4 of power balance device U2, output series AC contactor KM5, for controlling the input and output of power balance device.A.C. contactor KM6 with connect after A.C. contactor KM4, power balance device U2 and the form of A.C. contactor KM5 parallel connection access in the supply line of three-phase alternating current point, as emergency bypass unit, can be energized when device breaks down for subsequent use.Three-phase alternating current electrical input is represented with A, B, C, N represents the neutral line, L1, L2, L3 represent triple line and connect load, three current transformers TA1, TA2, TA3 are series at the output of circuit breaker Q F respectively in a phase of correspondence, and associate with neutral line N, simultaneously the signal output part of three current transformers is connected with 9,10,11 pins of controller U1 and 12 pins also associate with the neutral line, the current signal of detection reception supply line thus.And 13 of controller U1,14,15,16 pins detect by connecting L1, L2, L3, N line of load end the utilization voltage signal receiving supply line.

Three input contacts of described power balance device U2 represent with X, Y, Z respectively, wherein each contact has three branches, i.e. X1, X2, X3, Y1, Y2, Y3, Z1, Z2, Z3, the end of incoming cables of A.C. contactor KM1 connects X1, Y1, Z1 tri-points, the end of incoming cables of A.C. contactor KM2 connects X2, Y2, Z2 tri-points, the end of incoming cables of A.C. contactor KM3 connects X3, Y3, Z3 tri-points, connects neutral line N after the leading-out terminal parallel connection of these three A.C. contactors KM1, KM2, KM3.Meanwhile, 3,4,5,6,7,8 pins of controller U1 connect the coil formation parallel connection of A.C. contactor KM1, KM2, KM3, KM4, KM5, KM6 successively, then connect neutral line N.2 pins of controller U1 directly connect neutral line N, and 1 pin is connected between current transformer TA3 and circuit breaker Q F.

During work, power supply successively through circuit breaker Q F, three current transformers, A.C. contactor KM4, power balance device U2, A.C. contactor KM5 to load, now A.C. contactor KM6 is off state, controller U1 detects the current signal of supply line by current transformer, and the voltage signal of supply line is detected by load end, carry out coupling contrast balanced, then feedback result controlled it by the coil of the function of current in six A.C. contactors, the loading condition making power balance device adjust each phase in supply line realizes balance.When needs maintenance or when breaking down, A.C. contactor KM4 automatic or manual disconnects, and A.C. contactor KM6 automatic or manual closes, and can continue as load end and power.

By above-mentioned setting, three-phase imbalance voltage can be dropped to less than 2% by the utility model, extends the useful life of power consumption equipment, saves energy.

Above-described embodiment is only preferred embodiment of the present utility model; restriction not to the utility model protection range; in every case design principle of the present utility model being adopted, and the change carried out non-creativeness work on this basis and make, all should belong within protection range of the present utility model.

Claims

1. an electric power loads bascule, it is characterized in that, comprise the controller U1 with pin, be connected to the circuit breaker Q F of three-phase alternating current energization input, connect with circuit breaker Q F in each phase respectively and be connected the current transformer TA1 thinking that controller U1 provides current signal to input with the pin of controller U1, TA2 and TA3, at current transformer TA1, after TA2 and TA3, series connection access three-phase alternating current is to the power balance device U2 of the supply line of load, be connected to power balance device U2 and three current transformer TA1, TA2, A.C. contactor KM4 between TA3, be connected to the A.C. contactor KM5 between power balance device U2 and load, with connect after A.C. contactor KM4, the A.C. contactor KM6 of power balance device U2 and A.C. contactor KM5 parallel connection, and the A.C. contactor KM1 be arranged in parallel between three input contacts of three-phase and neutral line N is mated at power balance device U2, KM2 and KM3, wherein, the pin of described controller U1 is by six A.C. contactor KM1 in parallel, KM2, KM3, KM4, KM5, the coil of KM6 connects neutral line N, the pin of controller U1 accesses voltage signal by the output of power balance device U2, the pin of described controller U1 totally 16, the wherein coil of 6 connection A.C. contactors KM1, KM2, KM3, KM4, KM5, KM6,4 for accessing current signal, 4 for accessing voltage signal, one in all the other 2 is connected between current transformer TA3 and circuit breaker Q F, one is directly connected with neutral line N, for obtaining power supply.