CN203761056U - Cell energy storage-based wind driven electric generator electric energy quality controller - Google Patents

Abstract

The utility model discloses an cell energy storage-based wind driven electric generator electric energy quality controller. The electric energy quality controller comprises an inverter I and an inverter II that are connected in parallel, wherein the inverter I and the three-phase AC (alternating current) side of the inverter I are connected to the three-phase line inlet end of a power network in parallel through a filtering electric inductor and a contactor in sequence, and the inverter I and the DC side of the inverter II are connected to a DC bus; the electric energy quality controller further comprises energy storage battery groups connected at the two sides of the inverter II in parallel, a bidirectional DC/DC converter and a control circuit. A control method is also disclosed. The electric energy quality controller and the control method are characterized in that output power fluctuation and harmonic waves of a wind driven generator are independently compensated, and the quality of electric energy output by the wind driven generator is accurately controlled; through adoption of the DC (direct current) bus, energy storage batteries are shared to reduce battery capacity redundancy, and the energy output fluctuation of the wind driven generator is controlled and stabilized and suppressed through PI; meanwhile, the charge and discharge of the battery groups are controlled, and the response speed is high.

Description

Wind-driven generator electric energy quality controller based on battery energy storage

Technical field

The utility model relates to a kind of wind-driven generator electric energy quality controller, relates in particular to a kind of wind-driven generator electric energy quality controller based on battery energy storage.

Background technology

Wind power generation shared proportion in electric power system increases day by day, and the abundant area of China's wind resource is distributed in the weak Midwest of electrical network relative thin more, and the grid-connected normal operation of giving existing electric power system of a large amount of wind-powered electricity generation units brings great challenge.Because the energy density of wind energy is low, the feature such as randomness and unsteadiness, bring difficulty to the grid-connected control of Large-scale Wind Turbines.

The energy of wind-driven generator has very large fluctuation and uncertainty, and this feature very easily causes that distribution network voltage falls, flickering, even short term outage.Simultaneously, most of wind-driven generator can not directly provide the output of 50Hz AC energy, need after carrying out electric energy variation, power electronic device access electrical network, may inject a large amount of harmonic currents to electrical network like this, increase the possibility that resonance occurs in electrical network, the stability and security operation of serious threat power supply-distribution system.Therefore, consider power distribution network safety and user's request, numerous influencing factors of necessary comprehensive study wind-driven generator to distribution network electric energy quality, inject the quality of electric energy and control to the grid-connected place of wind-driven generator, and this mainly concentrates on voltage fluctuation and harmonic wave two aspects.

In order to reduce the fluctuation of wind-driven generator energy output, generally carry out complementation by energy-storage battery and wind-driven generator and realize, mainly to control at AC, each system is completely independent, and hardware cost is high, coordinates to control complicated.Particularly consider distributed power source and the dispersiveness that has of load, and when the various combination mode of dissimilar distributed power source and energy storage device, the coordination of its different control strategies and switch particularly complicatedly, is difficult for realization.

For the control of harmonic wave, often utilize active filter and passive filter.Active filter utilizes capacitance group, for specific subharmonic to stabilize effect fine, but cannot tackle the dynamic change of harmonic wave.Active filter can make up the deficiency of passive filter greatly, but need to add in addition prosthetics compensation equipment and power supply, and expense is higher, and resource has high input, and is unfavorable for the popularization of wind power generation.

Utility model content

In order to reduce the fluctuation of wind-driven generator energy output and to realize the control to harmonic wave, the utility model adopts following technical scheme:

A wind-driven generator electric energy quality controller based on battery energy storage, it comprises:

Two inverter I in parallel and inverter II, the three-phase alternating current side of described inverter I and inverter I is connected to electrical network three-phase end of incoming cables through filter inductance, contactor successively, the direct current side joint DC bus of described inverter I and inverter II, two inverter I in parallel and inverter II have formed harmonic compensation device;

Energy-storage battery group: the both sides that are parallel to inverter II;

Two-way DC/DC converter: be connected in parallel on the both sides of described energy-storage battery group, direct current side joint DC bus;

Control circuit: control circuit comprises controller, controller is connected with inverter I, inverter II and two-way DC/DC converter in parallel respectively by corresponding drive circuit, described controller is connected with Hall voltage transducer and Hall current sensor respectively by corresponding signal conditioning circuit, and described controller is also connected with contactor.

Described inverter I and inverter II are by the three-phase full-controlled bridge composition of three groups of insulation bipolar transistor anti-paralleled diode module compositions.

Described two-way DC/DC converter comprises the module that two insulated gate bipolar transistor anti-paralleled diodes form, and between this module, is provided with energy storage inductor.

The DC side of described inverter I is also connected with DC/DC converter, and DC/DC converter is connected with wind-driven generator, and inverter I both sides parallel connection is by capacitor C.

Described controller is dsp controller.

The beneficial effects of the utility model: the utility model adopts independently wind driven generator output power fluctuation and harmonic wave are compensated, and accurately controls the quality of power supply of wind-driven generator output; By DC bus, share energy-storage battery, reduce battery capacity redundancy, the utility model is controlled the fluctuation of stabilizing the output of wind-driven generator energy by PI, and to battery pack, charge and discharge are controlled simultaneously, fast response time.

Brief description of the drawings

Fig. 1 is wind-driven generator quality of power supply control block diagram;

Fig. 2 is DC/DC convertor controls schematic diagram;

Fig. 3 is harmonic compensation device control principle drawing;

Fig. 4 is control circuit schematic diagram.

Wherein, 1. inverter I, 2. inverter II, 3.DC/DC converter, 4. two-way DC/DC converter, 5. wind-driven generator, 6. controller, 7. contactor, 8. drive circuit, 9. signal conditioning circuit, 10. Hall current sensor, 11. Hall voltage transducers, 12. shunt choppers.

Embodiment

Below in conjunction with accompanying drawing and embodiment, the utility model is described in further detail.

As Figure 1 and Figure 4, a kind of wind-driven generator electric energy quality controller based on battery energy storage, it comprises:

Two inverter I1 in parallel and inverter II2, the three-phase alternating current side of described inverter I1 and inverter II2 is connected to electrical network three-phase end of incoming cables through filter inductance, contactor successively, the direct current side joint DC bus of described inverter I1 and inverter II2, two inverter I1 in parallel and inverter II2 have formed harmonic compensation device;

Be parallel to the energy-storage battery group of inverter II2 both sides;

Two-way DC/DC converter 4: be connected in parallel on the both sides of described energy-storage battery group, direct current side joint DC bus;

Control circuit: control circuit comprises controller 6, controller 6 is connected with shunt chopper 12 and two-way DC/DC converter 4 respectively by corresponding drive circuit 8, described controller 6 is connected with Hall voltage transducer 11 and Hall current sensor 10 respectively by corresponding signal conditioning circuit 9, described controller 6 is also connected with contactor 7, and shunt chopper 12 is inverter I1 and inverter II2 in parallel.

Described inverter I1 and inverter II2 are by the three-phase full-controlled bridge composition of three groups of insulation bipolar transistor anti-paralleled diode module compositions.

Described two-way DC/DC converter 4 comprises the module that two insulated gate bipolar transistor anti-paralleled diodes form, and between this module, is provided with energy storage inductor.

The DC side of described inverter I1 is also connected with DC/DC converter 3, and DC/DC converter 3 is connected with wind-driven generator 5, and inverter I1 both sides parallel connection is by capacitor C.

Described controller 6 is dsp controller.

Figure 2 shows that DC/DC convertor controls schematic diagram; The active power that in figure, wind-driven generator 5 is exported is P _g, obtain grid-connected average active power reference value through low-pass first order filter that is:

$P_W^{*}=P_G\frac{1}{1+\mathrm{sT}}$

Wherein time constant is T, and s is complex parameter. with grid-connected with reference to active-power P _tdeviation obtain the modulated current reference value of two-way DC/DC converter 4 by pi regulator that is:

k _p1for proportionality coefficient, k _i1for integral coefficient, S is complex parameter;

with energy-storage battery group output current i ₁compare again and obtain two-way DC/DC converter 4 Duty ratio control amount d by current PI adjuster ₁, finally realize the control to two-way DC/DC converter 4 by pwm pulse generator.

In Fig. 2, k _p2for proportionality coefficient, k _i2for integral coefficient, S is complex parameter.

Figure 3 shows that harmonic compensation device control principle drawing, finally generate harmonic compensation current i _cthree control signal i _ca, i _cb, i _cc.I in figure _la, i _lb, i _lcthe three-phase load electric current at battery energy storage system access point in parallel place, its harmonic components i _lha, i _lhb, i _lhcdetection adopt the dq0 detection method based on Instantaneous Power Theory.Use and and a of site place phase voltage u _sasynchronous cosine and sine signal, testing result can not be subject to the impact of voltage waveform distortion, and has good real-time.By the three-phase load current i under abc coordinate system _la, i _lb, i _lctransform to d axle, q axle and 0 shaft current i under dq0 coordinate system _d, i _q, i ₀transition matrix be:

$C_{\mathrm{dq}0}=\sqrt{\frac{2}{3}}\left[\begin{array}{ccc}\cos \mathrm{\ωt}& \cos (\mathrm{\ωt}-\frac{2}{3}\mathrm{\π})& \cos (\mathrm{\ωt}+\frac{2}{3}\mathrm{\π})\\ -\sin \mathrm{\ωt}& -\sin (\mathrm{\ωt}-\frac{2}{3}\mathrm{\π})& \text{-sin}(\mathrm{\ωt}+\frac{2}{3}\mathrm{\π})\\ \frac{1}{\sqrt{2}}& \frac{1}{\sqrt{2}}& \frac{1}{\sqrt{2}}\end{array}\right]$

By i _d, i _qby extracting and obtain flip-flop after low pass filter, and subtract each other and obtain alternating component with primary current as the reference value of harmonic current compensation signal. current reference value i with harmonic compensation device power output _df, i _qfafter budget, obtain actual output current reference value i _dr, i _qr; i _df, i _qfcan be by the meritorious reference power P of output _refwith idle reference power Q _refafter computing, draw P _refand Q _refcan be drawn by following formula:

Q _ref＝0

$P_{\mathrm{ref}}=\left\{\begin{array}{cc}0& P_{\mathrm{req}}\≤P\\ P_{\mathrm{req}}-P& P_{\mathrm{req}}>P\end{array}\right.$

Wherein P _reqfor the active power that electrical network needs wind-driven generator to export, P is the active power of the actual output of wind-driven generator.Final i _dr, i _qrthrough inverse transformation

$C_{\mathrm{dq}0}^{-1}=\sqrt{\frac{2}{3}}\left[\begin{array}{ccc}\cos \mathrm{\ωt}& -\sin \mathrm{\ωt}& \frac{1}{\sqrt{2}}\\ \cos (\mathrm{\ωt}-\frac{2}{3}\mathrm{\π})& -\sin (\mathrm{\ωt}-\frac{2}{3}\mathrm{\π})& \frac{1}{\sqrt{2}}\\ \cos (\mathrm{\ωt}+\frac{2}{3}\mathrm{\π})& -\sin (\mathrm{\ωt}+\frac{2}{3}\mathrm{\π})& \frac{1}{\sqrt{2}}\end{array}\right]$

Obtain the command signal i of shunt chopper offset current under abc coordinate _ca, i _cb, i _cc.

Be illustrated in figure 4 control circuit schematic diagram.Signal acquisition circuit is made up of multichannel Hall element and signal conditioning circuit, voltage, current information that can Real-time Collection monitoring point place.Voltage, current signal that controller 6 is responsible for gathering are processed, obtain the control signal of shunt chopper 12 and two-way DC/DC converter 4 by algorithm shown in Fig. 2, Fig. 3, finally by drive circuit 8, shunt chopper 12 and two-way DC/DC converter 4 are controlled, realized the function of the regulation and control wind-driven generator output quality of power supply.Can and control parameter and set regulation index.

By reference to the accompanying drawings embodiment of the present utility model is described although above-mentioned; but the not restriction to the utility model protection range; one of ordinary skill in the art should be understood that; on the basis of the technical solution of the utility model, those skilled in the art do not need to pay various amendments that creative work can make or distortion still in protection range of the present utility model.

Claims (4)

1. the wind-driven generator electric energy quality controller based on battery energy storage, is characterized in that, it comprises:

Two inverter I in parallel and inverter II, the three-phase alternating current side of described inverter I and inverter I is connected to electrical network three-phase end of incoming cables through filter inductance, contactor successively, the direct current side joint DC bus of described inverter I and inverter II, two inverter I in parallel and inverter II have formed harmonic compensation device;

Energy-storage battery group: the both sides that are parallel to inverter II;

Two-way DC/DC converter: be connected in parallel on the both sides of described energy-storage battery group, direct current side joint DC bus;

Control circuit: control circuit comprises dsp controller, dsp controller is connected with inverter I, inverter II and two-way DC/DC converter in parallel respectively by corresponding drive circuit, described dsp controller is connected with Hall voltage transducer and Hall current sensor respectively by corresponding signal conditioning circuit, and described dsp controller is also connected with contactor.

2. a kind of wind-driven generator electric energy quality controller based on battery energy storage as claimed in claim 1, is characterized in that, described inverter I and inverter II are by the three-phase full-controlled bridge composition of three groups of insulation bipolar transistor anti-paralleled diode module compositions.

3. a kind of wind-driven generator electric energy quality controller based on battery energy storage as claimed in claim 1, it is characterized in that, described two-way DC/DC converter comprises the module that two insulated gate bipolar transistor anti-paralleled diodes form, and between this module, is provided with energy storage inductor.

4. a kind of wind-driven generator electric energy quality controller based on battery energy storage as claimed in claim 1, it is characterized in that, the DC side of described inverter I is also connected with DC/DC converter, and DC/DC converter is connected with wind-driven generator, and inverter I both sides parallel connection is by capacitor C.