CN201533172U - Filter and transformation integrated device of photovoltaic grid-connected inverted power supply - Google Patents

Abstract

The utility model discloses a filter and transformation integrated device of a photovoltaic grid-connected inverted power supply, which mainly comprises the following portions: (1) a device body comprising an iron core, a winding, an insulation component and a lead, (2) a cooling device, (3) a protecting device comprising a temperature relay, a temperature measuring device and the like, and (4) an insulating sleeve comprising a shrinkable tube and a wax duct. The filter and transformation integrated device of a photovoltaic grid-connected inverted power supply has the advantages that after utilizing the filter and transformation integrated device, a reactor needing independent filter shaping can be saved, thereby not only reducing volume of the grid-connected inverted power supply, saving cost of the grid-connected inverted power supply, but also further improving output harmonic component, and reducing high-frequency noise generated during operation of the reactor.

Description

The filtering of photovoltaic grid-connected inversion power supply, transformation integrated apparatus

Technical field

The utility model relates to the photovoltaic electric station grid connection system, is the core control equipment of parallel network reverse power-supply system, directly applies to MW level light-focusing type (CPV) power station of being incorporated into the power networks.

Background technology

Solar energy power generating is cleaning, an emerging generation mode the safest, the most with the largest potentiality in the present known generation mode.Serious day by day along with energy shortage and problem of environmental pollution is significant to the research and the application of photovoltaic generation.China was successfully applied to the dfh-2 satellite first in beginning solar cell research in 1958 in 1971, began to be used for ground in 1973.In the age eight, nine o'clock 20th century, be limited to price and output, China photovoltaic market is development in slowly, removes satellite power supply, and solar cell is used for the small-power system more on the ground, and successively from many solar cell growth lines of external introduction.2000, China's solar cell accumulative total consumption was 15MW.From the nineties later stage so far, Chinese photovoltaic generation has all been obtained very big progress in industrialization and application facet, has brought into play important function in the power construction away from the electrical network area.2002, former State Planning Commission started " the energising plan of western provinces and regions Wu Dian township ", and plan solves the electrical problem in 780 Wu Dian townshiies, western seven provinces and regions by photovoltaic and small-size wind power-generating, and this project has stimulated the development of China's photovoltaic industry greatly.At present, China at photovoltaic plant, be incorporated into the power networks or independent operating inverter, photovoltaic family have all been obtained certain progress with aspects such as system, wind-light complementary systems, some solar energy specialized factories have appearred.As the parallel network reverse power supply of one of solar power generation core, significant for the utilance and the serviceability that improve photovoltaic device, just develop towards modularization, standardization, intellectuality, industrialized direction.

Summary of the invention

Purpose: filtering, transformation integrated apparatus by the parallel network reverse power supply improve alternating voltage and the alternating current harmonic component that parallel network reverse is exported, and reduce the interference of parallel network reverse power supply to electrical network.

Technical solution of the present invention is: the critical piece of the filtering of parallel network reverse power supply, transformation integrated apparatus comprises following a few part: (1) device body: comprise iron core, winding, insulating element and lead-in wire; (2) cooling device; (3) protective device: comprise temperature relay and temperature measuring equipment etc.; (4) insulating sleeve: comprise heat-shrink tube, ceratuba.

Beneficial effect: after adopting this filtering, transformation integrated apparatus, just can omit the reactor that need carry out filter shape separately, not only reduced the volume of parallel network reverse power supply, saved parallel network reverse power supply cost, but also improved the output harmonic wave component, the high frequency noise that has produced when having reduced reactor work.

Description of drawings

Fig. 1 is a structural representation of the present invention.

Embodiment

Below in conjunction with the drawings and specific embodiments the present invention is done explanation in further detail.

The problem that needs solution: do not adopt before filtering, the transformation integrated apparatus, combining inverter is to carry out filter shape by reactor, reduce the harmonic component of output voltage and electric current, when working, reactor can produce strong high frequency noise, and the voltage difference on reactor can be with the form consumption of heat, a large amount of heats also needs to increase heat abstractor and dispels the heat, and increased the inversion efficiency that the cabinet volume has also reduced whole parallel network reverse power supply.

Technical scheme: the basic principle of transformer: when a sinusoidal voltage U1 is added in the primary coil two ends, alternating current I1 is just arranged in the lead and produce alternating flux ф 1, it passes primary coil and secondary coil along iron core and forms closed magnetic circuit.Induce mutual inductance electromotive force U2 in secondary coil, ф 1 also can induce a self-induced e.m.f E1 on primary coil simultaneously, and amplitude is close on the contrary mutually with the making alive U1 of institute direction for the direction of E1, thereby has limited the size of I1.For the existence that keeps magnetic flux ф 1 just needs certain power consumption, and transformer itself also has certain loss, although secondaryly do not connect load this moment, still has certain electric current in the primary coil, and this electric current is called " no-load current ".

If secondaryly connect load, secondary coil just produces electric current I 2, therefore and produce magnetic flux ф 2, the direction of ф 2 is opposite with ф 1, play a part to cancel each other, magnetic flux total in the iron core is reduced to some extent, thereby elementary self induction voltage E1 is reduced, its result increases I1, and visible primary current and secondary load have substantial connection.I1 increases when the secondary load electric current strengthens, and ф 1 also increases, and ф 1 increases and partly just in time replenished that part of magnetic flux of being offset by ф 2, and is constant to keep in the iron core total magnetic flux.If do not consider the loss of transformer, can think the just elementary electrical power that obtains from power supply of power of a desirable transformer secondary output load consumption.Transformer can change secondary voltage by the number of turns that changes secondary coil as required, but can not change the power that allows load consumption.

Mainly contain resistance, electric capacity, several parts compositions of inductance in the loop of electrical system, inductance is to have to suppress the effect that electric current changes usually, and it can make the alternating current phase shift. therefore there being the stationary induction apparatus of the Wound-rotor type of inductance effect to call reactor.The method that we often adopt in electric power system has series reactor and shunt reactor.Series reactor is to be used for limiting short-circuit current, usually also in filter with capacitors in series or in parallelly be used for limiting higher Harmonics in Electric Power Network.

Inductance is exactly the solenoid coil (can contain cored) of an indirect current.Because coil can produce induced voltage in the moment of energising, and this induced voltage oppositely is the magnetic flux that resistance institute galvanization forms, so there is a kind of inhibition in inductance component to the electric current that changes, and it can not be passed through, and this is called induction reactance.The institute messenger changes fast more, and induction reactance is just big more, so the characteristics of inductance component are that the frequency of signal is high more, and device is just strong more to the obstruction of this signal.If to the logical last direct current signal of inductance, device does not hinder signal so.Inductance component uses on power supply the inhibition of alternating current, is installed in the circuit after the rectification, and can block AC signal, and allow direct current signal pass through, be that AC signal has been filtered out seemingly.So inductance (the perhaps combination of inductance and other components and parts) is called filter again.

The harmonic elimination reactor is to use the reactor on AC system, is connected in order to the tuning filtering loop with capacitor, makes its resonance within the specific limits, in order to reduce resistance or elimination harmonic wave.The harmonic elimination reactor both can be connected in parallel in the system, also can be connected in the system.The harmonic elimination reactor is single-phase or three-phase reactor (oil immersed type or sense formula also can adopt the shunting tap coil, and its inductance value can be regulated in limit range).

When the harmonic elimination reactor is parallel connection method in system, bear the transient process of shoving that switching manipulation produces.When reactor is tandem-type connection in system, also to bears and to predict the overcurrent that the system failure produces.The harmonic elimination reactor is tandem-type connection or parallel connection method in system, decides its rated value whether to have curtage under power frequency and the tuned frequency according to its application.In the series circuit that resistance, inductance and electric capacity are formed, when capacitive reactance XC equates with inductive reactance xl, i.e. XC=XL, the voltage U in the circuit is identical with the phase place of electric current I, and circuit presents pure resistive, and this phenomenon is series resonance (being also referred to as voltage resonance).When circuit generation series resonance, the impedance Z of circuit=√ R2+XC-XL2=R, total impedance minimum in the circuit, electric current will reach maximum.

When resonance takes place, because induction reactance and capacitive reactance equate, so the voltage effective value at inductance and electric capacity two ends equates i.e.: UL=UC.Opposite owing to its phase place again, so these two voltages are cancelled out each other.Voltage effective value at electric capacity or inductance is: UL=UC=XLI0=ω 0LI0=ω 0LU/R.ω 0L/R is called the quality factor of resonant circuit in the formula, its representative voltage ratio.Be UC/U or UL/U.Quality factor are to weigh an important parameter of resonant circuit characteristic.Big more as reactance in the circuit, resistance is more little, and then quality factor are high more.Therefore the magnitude of voltage on electric capacity or the inductance will be than big many of applied voltage.The quality factor of general inductance, capacitor resonant circuit can reach tens even hundreds of.So series resonance is voltage resonance again.In electric power system, series resonance will produce the overvoltage that exceeds electrical network rated voltage several times, and the safety of power equipment is caused very big harm.In the R-L-C series circuit, the synchronous phenomenon of line scan pickup coil side voltage and current appears series resonance.

The present invention introduces the harmonic elimination reactance on the electromagnetic induction characteristic of transformer, thereby has cancelled independent reactor, and the filtering, the transformation that have reached the photovoltaic grid-connected inversion power supply are integrated.

Though the present invention with preferred embodiment openly as above; but they are not to be used for limiting the present invention; anyly be familiar with this skill person; without departing from the spirit and scope of the invention; from when can doing various variations or retouching, so being as the criterion of should being defined with the application's claim protection range of protection scope of the present invention.

Claims (1)

1. the filtering of a parallel network reverse power supply, transformation integrated apparatus is characterized in that it consists of the following components:

(1) device body: comprise iron core, winding, insulating element and lead-in wire;

(2) cooling device;

(3) protective device: comprise temperature relay and temperature measuring equipment;

(4) insulating sleeve: comprise heat-shrink tube, ceratuba.

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