CN108599191B - A kind of electric power spring power decoupling control method of belt current inner ring - Google Patents
A kind of electric power spring power decoupling control method of belt current inner ring Download PDFInfo
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- CN108599191B CN108599191B CN201810182677.XA CN201810182677A CN108599191B CN 108599191 B CN108599191 B CN 108599191B CN 201810182677 A CN201810182677 A CN 201810182677A CN 108599191 B CN108599191 B CN 108599191B
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/24—Arrangements for preventing or reducing oscillations of power in networks
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/01—Arrangements for reducing harmonics or ripples
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/12—Circuit arrangements for ac mains or ac distribution networks for adjusting voltage in ac networks by changing a characteristic of the network load
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/40—Arrangements for reducing harmonics
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Abstract
The invention discloses a kind of electric power spring power decoupling control method of belt current inner ring, the electric power spring system includes a bidirectional DC power supply vdc, a single-phase electricity potential source type inverter module, a LC low-pass filter；The switching of by-pass switch S control electric power spring.Electric power spring by filter capacitor C connect with non-critical loads again it is in parallel with critical loads after through line impedance Z1With power grid vGIt is connected and constitutes the real application systems of electric power spring.The present invention is directed to micro-capacitance sensor voltage and power swing problem caused by intermittence and unstability because of generation of electricity by new energy, it is proposed a kind of electric power spring power decoupling control method of belt current inner ring, on the one hand the fluctuation of generation of electricity by new energy power can be transferred on electric power spring arrangement and non-critical loads, to guarantee the stabilization of critical loads voltage and power；On the other hand, so that power network current waveform more tends to sine, simultaneity factor can obtain more good dynamic property for the addition of current inner loop.
Description
Technical field
The present invention relates to the application field of power electronics in the power system, a kind of belt current inner ring is related in particular to
Electric power spring power decoupling control method.
Background technique
Currently, China has entered the critical period of energy low-carbon transition, and the new energy developing contradiction such as wind energy, solar energy is convex
Aobvious, phenomena such as light protrusion is abandoned in abandonment, and the bottleneck of grid-connected consumption is not solved effectively yet.Energy resource structure transition center of gravity to point
The transfer of the cloth energy has become trend；Online, on-site elimination will become normality on the spot；The mode of " generating power for their own use, remaining electricity online " will
Gradually promoted.However, with the increase year by year of the generations of electricity by new energy installed capacity such as roof photovoltaic, small-size wind power-generating, it is micro-
The stable operation of power grid will will receive strong influence.
For the micro-capacitance sensor reliability service for guaranteeing the generation of electricity by new energy containing high permeability, the energy storage devices such as battery group are generally used
As the important means of peak load shifting, but this belongs to passive type energy storage mode, and the charge and discharge of more number will affect its use
Service life will lead to cost using the battery group of larger capacity and significantly rise to improve reliability.
Summary of the invention
The technical problems to be solved by the present invention are: for the unstable caused public company of generation of electricity by new energy output power
Contact (Point of Common Coupling, PCC) voltage and power swing problem, propose a kind of electric power of belt current inner ring
On the one hand the fluctuation of generation of electricity by new energy power can be transferred to electric power spring arrangement and non-by spring power decoupling control method
On critical loads, to guarantee the stabilization of critical loads voltage and power；On the other hand, the addition of current inner loop is so that power grid wink
When current waveform more tend to sine, simultaneity factor can obtain more good dynamic property.The typical case system of electric power spring
System includes conventional electric power generation output voltage source vG, line resistance R1, line inductance L1, critical loads ZC, non-critical loads ZNC, one
Monophase electric power spring system；The Monophase electric power spring system is second generation Monophase electric power spring system, includes bidirectional, dc electricity
Source vdc, a single-phase electricity potential source type inverter module, a LC low-pass filter；By-pass switch S controls the switching of electric power spring,
Points of common connection PCC is electric power spring and critical loads ZCWith line impedance Z1Tie point.
The present invention uses following technical scheme to solve above-mentioned technical problem:
A kind of electric power spring power decoupling control method of belt current inner ring, it is characterised in that increase current inner loop reconciliation
Coupling compensation term, a control period include the following steps:
1) the voltage signal v of critical loads is acquiredCWith the current value i at points of common connection PCC1, calculate and be input to electric power bullet
The active-power P of spring；
2) outer voltage and active power outer loop control, wherein by active-power P and voltage signal vCRespectively with it is given
Active-power PrefAnd given voltage effective value VrefIt makes comparisons, two differences pass through outer ring deviation controller respectively,
Output is respectively d, q shaft current reference value idrefAnd iqref；
3) current inner loop control, wherein by idrefAnd iqrefActual samples electric current warp is subtracted as current reference value, and by it
Convert obtained d, q shaft current id、iqAfter be respectively fed to inner ring deviation controller；
4) current inner loop decoupling control, wherein the output of inner ring deviation controller is through id、iqCross coupling compensation and voltage
The voltage reference value v of d axis and q axis is obtained after feedforward compensationdrefAnd vqref, by the vdrefAnd vqrefIt is transformed to the defeated of inverter
Voltage reference value v outrefAgain as the modulating wave v of SPWM after clipping_ref；
5) by the v_refCompared with triangular carrier, in v_refPower switch is controlled with the natural intersection point moment of triangular carrier
The on-off of device is to obtain the driving signal of the switching tube of the single-phase electricity potential source type inverter module.
Preferably, in the outer voltage and active power outer loop control step, the outer ring deviation controller is ratio
Example integral controller or proportional plus integral plus derivative controller.
Preferably, in the current inner loop control step, the actual samples electric current converts to obtain the d, q through Park
Shaft current id、iq。
Preferably, in the current inner loop control step, the inner ring deviation controller be pi controller or
Proportional plus integral plus derivative controller.
Preferably, in the current inner loop decoupling control step, by Park inverse transformation by the vdrefAnd vqrefTransformation
For the output voltage reference value v of inverterref。
Preferably, the DC voltage of the single-phase electricity potential source type inverter module is obtained by battery or by single-phase power grid
Voltage is followed by electrolytic capacitor acquisition by PWM rectifier, which is greater than 311V.
The invention adopts the above technical scheme compared with prior art, has following technical effect that
1, it can guarantee the stabilization of critical loads voltage and power
The stabilization of critical loads voltage and power when this control method is intended to maintain new-energy grid-connected, improves electric energy matter
Amount.Monophase system by construct virtual orthographic amount may be implemented from rest frame to rotating coordinate system under coordinate transform, can
Of ac is converted to DC quantity；Power outer ring, outer voltage and PI controller, which is thus used only, may be implemented active power
With voltage DAZ gene.As shown in figure 3, PCC voltage gives the emulation wave being scheduled under 220V and the given situation of active power difference
Shape comparison diagram, it can be seen that the voltage effective value at critical loads be stable in 220V and input power substantially can well with
Upper given value.
2, system has more good dynamic property
Current inner loop increases the control to power grid Injection Current, on the one hand can control electricity by the way that suitable threshold value is arranged
The size of net Injection Current maintains it in safe range of operation, increases the safety of system.Another aspect inner ring control
Device processed can effectively inhibit the influence of harmonic current, enhance the sine degree of power grid transient current, while the solution based on interior circular current
Grid-connected current is decomposed into active current and reactive current component by coupling compensation policy, using two independent PI controllers
Can with independent control watt current and reactive current, thus achieve the purpose that control active power and reactive power it is significant promoted
The dynamic property of system.
3, energy-storage units needed for application system are less
When encountering significantly power swing, required energy-storage units also must accordingly increase traditional energy storage device
Greatly, the fluctuation of the instantaneous transfer power of the energy of power control used by electric power spring arrangement used in this system, from the angle of control
Degree proposes a solution, therefore required energy-storage battery capacity is relatively small.
4, practicability is high, application prospect is extensive
Emphasis of the present invention solves the problems, such as voltage and power swing brought by new-energy grid-connected, while improving the dynamic of system
State property energy can promote the popularization and application of generation of electricity by new energy, and system is simple and reliable, there is very high practical value and application prospect.
Detailed description of the invention
Fig. 1 is electric power spring system structure chart of the invention；
Fig. 2 is the power control block diagram of electric power spring system of the invention；
Fig. 3 is PCC voltage of the invention in 220V and active power difference is to the simulation waveform comparison diagram fixed, and is successively
PCC voltage vC, given power PrefWith measurement power P, PCC electric current i1And PCC voltage effective value vcrmsSimulation waveform.
Specific embodiment
Technical solution of the present invention is described in further detail with reference to the accompanying drawing:
The present invention proposes a kind of electric power spring power decoupling control method of belt current inner ring, on the one hand can be by new energy
The fluctuation of power generation output voltage and its power is transferred in electric power spring arrangement and non-critical loads, to guarantee critical loads
The stabilization of voltage and power, on the other hand, the addition of current inner loop, while can so that power grid transient current waveform more tends to sine
To obtain more good dynamic performance.
As shown in Figure 1, the typical case system of electric power spring includes conventional electric power generation output voltage source vG, line resistance R1, line
Road inductance L1, critical loads ZC, non-critical loads ZNC, a Monophase electric power spring system；The Monophase electric power spring system is
Second generation Monophase electric power spring system includes bidirectional DC power supply vdc, a single-phase electricity potential source type inverter module, a LC it is low
Bandpass filter；The switching of by-pass switch S control electric power spring.Exchange side one end of the inverter module connects LC low-pass filtering
One end of L in device；The other end of the L is not only connected with one end of capacitor C, also with critical loads ZCOne end be connected；It is described
The other end of capacitor C in addition to non-critical loads ZNCOne end be connected, also exchange the another defeated of side with the inverter module
Outlet is connected；The non-critical loads ZNCThe other end ground connection；The conventional electric power generation output voltage source vGWith line resistance R1With
Line inductance L1One end of critical loads, v are connected to after series connectionGThe other end ground connection.The single-phase electricity potential source type inverter module
DC side input dc power.Further, the DC voltage of inverter module can also be obtained by battery, which should be big
In 311V.
For easy analysis, critical loads and non-critical loads are equivalent to a pure resistance when emulation.Wherein, inversion electricity
The DC voltage on road is 400V；LC filtering parameter is respectively 2.5mH and 26 μ F；Critical loads ZC50 Ω of pure resistance is chosen, it is non-
The pure resistance Z of 50 Ω of critical loadsNCInstead of power transmission line and line loss are equivalent with the tandem compound of 1 Ω and 2.5mH, power grid electricity
Voltage-frequency rate is 50Hz, and taking switching frequency in inverter is 20kHz.
As shown in Fig. 2, a control period of the electric power spring power decoupling control of belt current inner ring includes the following steps:
1) the voltage signal v of critical loads is acquiredCWith the current value i at PCC1, calculate and be input to having for electric power spring system
Function power P；
2) by active-power P and voltage signal vCRespectively with given active-power PrefAnd given voltage is effective
Value VrefIt makes comparisons.Two differences pass through a PID controller respectively, and output is respectively d, q shaft current reference value idrefWith
iqref；
3) by the idrefAnd iqrefThe i obtained with actual samples electric current through Park inverse transformationdAnd iqIt makes comparisons, the two is poor
Output valve of the value after PID regulator adds d respectively, and the cross-couplings item of q shaft current and the feedforward compensation term of voltage obtain d axis
With the voltage reference value v of q axisdrefAnd vqref；
4) voltage reference value of d axis and q axis is converted to the output voltage reference value v of inverterrefThe conduct after clipping again
SPWM modulating wave v_ref；
5) by above-mentioned v_refCompared with triangular carrier, in v_refPower switch is controlled with the natural intersection point moment of triangular carrier
The on-off of device is to obtain the switching tube S of single-phase electricity potential source type inverter module11, switching tube S12, switching tube S13, switching tube S14
Driving signal: by the above process so that inverter module output alternating voltage fundametal compoment and vESPhase is identical；Its
In, the frequency of triangular carrier is 20kHz, and peak-to-peak value 2V, the dead time of driving signal is 2 μ s；The input voltage of inverter
It is to be followed by electrolytic capacitor by PWM rectifier by single-phase mains voltage and obtained；
6) this strategy maintains the stabilization of its input power while ensure that the stabilization of critical loads voltage, then ties
The control flow in beam this secondary control period waits next control period.
A kind of electric power spring power decoupling control for belt current inner ring that control method of the invention is related to, passes through d axis
Controller controls the active power of electric power spring arrangement and non-critical loads, and q axis controller controls network system critical loads
Voltage.Through simulating, verifying, the dynamic and static properties of system are very outstanding.
The above, is only the preferred embodiment of the present invention, is not the limit for making any other form to the present invention
System, and made any modification or equivalent variations according to the technical essence of the invention, still fall within present invention model claimed
It encloses.
Claims (6)
1. a kind of electric power spring power decoupling control method of belt current inner ring, the electric power spring includes bidirectional DC power supply
vdc, a single-phase electricity potential source type inverter module, a LC low-pass filter；By-pass switch S controls the switching of electric power spring, electricity
Power spring passes through filter capacitor C and non-critical loads ZNCSeries connection again with critical loads ZCThrough line impedance Z after parallel connection1With power grid vG
It is connected, points of common connection PCC is electric power spring and critical loads ZCWith line impedance Z1Tie point；
Characterized by the following steps:
1) the voltage signal v of critical loads is acquiredCWith the current value i at points of common connection PCC1, calculate and be input to electric power spring
Active-power P；
2) outer voltage and active power outer loop control, wherein by active-power P and voltage signal vCRespectively with it is given active
Power PrefAnd given voltage effective value VrefIt makes comparisons, two differences pass through outer ring deviation controller, output point respectively
It Wei not d, q shaft current reference value idrefAnd iqref；
3) current inner loop control, wherein by idrefAnd iqrefActual samples electric current i is subtracted as current reference value, and by it1Through becoming
The d got in return, q shaft current id、iqAfter be respectively fed to inner ring deviation controller；
4) current inner loop decoupling control, wherein the output of inner ring deviation controller is through id、iqCross coupling compensation and electric voltage feed forward
The voltage reference value v of d axis and q axis is obtained after compensationdrefAnd vqref, by the vdrefAnd vqrefIt is transformed to the output electricity of inverter
Press reference value vrefAgain as the modulating wave v of SPWM after clipping_ref；
5) by the v_refCompared with triangular carrier, in v_refDevice for power switching is controlled with the natural intersection point moment of triangular carrier
On-off to obtain the driving signal of the switching tube of the single-phase electricity potential source type inverter module.
2. the electric power spring power decoupling control method of belt current inner ring according to claim 1, which is characterized in that in institute
It states in outer voltage and active power outer loop control step, the outer ring deviation controller is pi controller.
3. the electric power spring power decoupling control method of belt current inner ring according to claim 1, which is characterized in that in institute
It states in current inner loop control step, the actual samples electric current converts to obtain the d, q shaft current i through Parkd、iq。
4. the electric power spring power decoupling control method of belt current inner ring according to claim 1, which is characterized in that in institute
It states in current inner loop control step, the inner ring deviation controller is pi controller.
5. the electric power spring power decoupling control method of belt current inner ring according to claim 1, which is characterized in that in institute
It states in current inner loop decoupling control step, by Park inverse transformation by the vdrefAnd vqrefIt is transformed to the output voltage of inverter
Reference value vref。
6. the electric power spring power decoupling control method of belt current inner ring according to claim 1, which is characterized in that described
The DC voltage of single-phase electricity potential source type inverter module is obtained by battery or by single-phase mains voltage after PWM rectifier
Electrolytic capacitor acquisition is connect, which is greater than 311V.
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| CN109861237A (en) * | 2019-01-30 | 2019-06-07 | 东南大学 | A kind of multiple electric power spring coordinated control systems and control method based on droop characteristic |
| CN110212543B (en) * | 2019-05-08 | 2022-12-06 | 湖南大学 | Power spring system considering non-critical load and control method thereof |
| CN110165677B (en) * | 2019-05-10 | 2023-04-28 | 上海电力学院 | Voltage stable control method for single-phase alternating-current power spring |
| CN110212541B (en) * | 2019-06-27 | 2023-05-30 | 上海电力学院 | Direct-current power spring control method based on predictive model |
| CN111313412A (en) * | 2020-03-17 | 2020-06-19 | 浙江华电器材检测研究所有限公司 | Method for analyzing influence of multi-access electric vehicle charging pile on power grid harmonic waves |
| CN112436520B (en) * | 2020-11-27 | 2023-11-17 | 上海电力大学 | Feedback linearization decoupling control method for alternating-current power spring |
| CN112327637B (en) * | 2020-12-01 | 2022-05-27 | 上海电力大学 | Power spring feedback linearization control method based on robust disturbance observation |
| CN112688350A (en) * | 2020-12-21 | 2021-04-20 | 南京工程学院 | Power spring voltage regulation strategy and system based on fractional calculus control and power distribution network |
| CN113013899B (en) * | 2021-03-22 | 2023-02-10 | 华南理工大学 | Fractional order electric spring control method with real-time adjustable order |
| CN113162047B (en) * | 2021-04-02 | 2022-04-22 | 华南理工大学 | Power spring multifunctional control method based on cascade generalized integrator |
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| JP2000287389A (en) * | 1999-03-29 | 2000-10-13 | Yoshiaki Masuno | Dissipation power controller |
| US7327125B2 (en) * | 2005-02-17 | 2008-02-05 | Qualcomm Incorporated | Power supply circuit having voltage control loop and current control loop |
| CN105703381A (en) * | 2015-11-27 | 2016-06-22 | 华北电力大学 | Power damping synchronization control method suitable for VSC-HVDC connection extremely-weak AC power grid |
| CN106300364A (en) * | 2016-08-29 | 2017-01-04 | 国网江苏省电力公司电力科学研究院 | The voltage dip of electrically-based spring administers circuit and administering method thereof |
| CN106505642B (en) * | 2016-10-18 | 2018-11-30 | 华中科技大学 | A kind of AC/DC decoupling control method and its application in flexible HVDC transmission system |
| CN107196321B (en) * | 2017-07-17 | 2020-08-04 | 上海交通大学 | Method for improving steady-state operation range of power spring |
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