CN109004661A - The closed loop control method of three-phase imbalance equipment based on internal model principle and error iteration PI - Google Patents

The closed loop control method of three-phase imbalance equipment based on internal model principle and error iteration PI Download PDF

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Publication number
CN109004661A
CN109004661A CN201810873309.XA CN201810873309A CN109004661A CN 109004661 A CN109004661 A CN 109004661A CN 201810873309 A CN201810873309 A CN 201810873309A CN 109004661 A CN109004661 A CN 109004661A
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phase
closed loop
loop control
error
control method
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CN201810873309.XA
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Inventor
宋力
徐小明
招耀星
黄泳峰
程勇钊
陈建华
麦伟文
钱应杰
张文静
张海金
李致莹
钟建伟
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Guangdong Harmony Intelligent Technology Co Ltd
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Guangdong Harmony Intelligent Technology Co Ltd
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Priority to CN201810873309.XA priority Critical patent/CN109004661A/en
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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
    • H02J3/26—Arrangements for eliminating or reducing asymmetry in polyphase networks
    • 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
    • H02J3/18—Arrangements for adjusting, eliminating or compensating reactive power in networks
    • H02J3/1821—Arrangements for adjusting, eliminating or compensating reactive power in networks using shunt compensators
    • H02J3/1835—Arrangements for adjusting, eliminating or compensating reactive power in networks using shunt compensators with stepless control
    • H02J3/1842—Arrangements for adjusting, eliminating or compensating reactive power in networks using shunt compensators with stepless control wherein at least one reactive element is actively controlled by a bridge converter, e.g. active filters
    • 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
    • Y02E40/30—Reactive power compensation
    • 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
    • Y02E40/50—Arrangements for eliminating or reducing asymmetry in polyphase networks

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Supply And Distribution Of Alternating Current (AREA)

Abstract

The present invention relates to a kind of closed loop control methods of three-phase imbalance equipment based on internal model principle and error iteration PI, sample current on line side and carry out closed-loop control, directly control control target, realize good compensation effect；Possess current inner loop simultaneously, separation harmonic current control outer ring and busbar voltage control outer ring, it is ensured that busbar voltage it is constant, enhance the use scope of equipment；Harmonic current controls the controller that outer ring uses internal model principle, introduces DC component and removes link, the introducing of internal mode controller greatly improves the tracking effect of harmonic wave；Busbar voltage ring introduces error iteration PI controller, reduce the error of busbar voltage stable state control, while improving the response speed of busbar voltage ring in the case of fundamental active load sudden change, it ensures the safety of the voltage of bus and the stability of compensation effect, reaches and change violent occasion in fundamental wave load and still with stable operation and can ensure good compensation effect.

Description

The closed-loop control of three-phase imbalance equipment based on internal model principle and error iteration PI Method
Technical field
The present invention relates to power electronics control fields, more particularly to a kind of three based on internal model principle and error iteration PI The mutually closed loop control method of uneven equipment.
Background technique
With the development of economy, the load of distribution becomes to become increasingly complex, especially as the continuous development of rural economy, agriculture The three-phase imbalance situation of village's power distribution network is more next serious, certain serious normal lifves for affecting rural resident in place.
The abatement equipment of three-phase imbalance gradually obtained the concern of society in recent years, and the presence or absence of conventional source capacitance compensation is set It is standby, active three-phase imbalance compensation equipment etc..It is passive and active in fact similar with APF with the TSC of power quality industry, have same The respective advantage and disadvantage of the characteristic of sample.But for the scene of three-phase imbalance, the compensation effect of TSC equipment is very limited, it is main If because it is the three-phase electricity because the three-phase investment of single-phase load is unbalanced caused that the three-phase imbalance of power distribution network is in the majority Unbalanced characteristics exhibit is flowed in the imbalance (fundamental wave negative sequence and fundamental wave zero sequence composition) of fundamental current, 3-13 low-order harmonic The imbalance of the electric current of (harmonic wave includes positive-negative sequence and zero sequence composition).
So occur many three-phase imbalance equipment being transformed using APF or SVG in the market, these equipment it is universal Control method is the open loop control mode that detection load carries out uneven composition and Resonance Wave Composition, this mode there are compensation effect compared with Difference, scene are not easy to the problem of debugging, and especially three-phase imbalance equipment is typically installed on utility poles, is not easy to very much Installation.
So the demand of the three-phase imbalance equipment based on closed loop control method is more more and more urgent, closed loop control method is not only It can perfectly solve the problems, such as to be not easy to debugging on electric pole, while may insure extraordinary compensation effect.
Summary of the invention
The present invention provides a kind of closed loop control method of three-phase imbalance equipment based on internal model principle and error iteration PI, It can be readily appreciated that it is easy to accomplish, still with stable operation and it can ensure good compensation effect in the violent occasion of fundamental wave load variation Fruit.
Its technical solution is as follows: a kind of closed-loop control of the three-phase imbalance equipment based on internal model principle and error iteration PI Method, exchange side is directly connected to by three pole reactor and power grid in the topological diagram of three-phase imbalance equipment, and DC side is using two groups The capacitor of division is connected, and the midpoint of two groups of capacitors is connect as middle line with power grid N line, as zero sequence access, passes through following step It is rapid to realize control:
Step S1: sampling three-phase network voltage obtains the angle wt of network voltage using phaselocked loop, as control transformation Phase angle foundation；
Step S2: acquisition power network current isa, isb, isc obtain the electric current of two axis of D, Q using ABC/DQ coordinate transform Ingredient id, iq, and DC component removal is carried out to id, iq and is calculated, other current components without containing fundamental positive sequence are obtained, And converted using DQ/ABC coordinate system, obtain three phase harmonic instruction ∑ iabc；
Step S3:0 makes the difference as given with three phase harmonic instruction ∑ iabc, error signal e rr is obtained, by internal model control Device controls to obtain three-phase compensation electric current ira、irb、irc；
Step S4: sampling busbar voltage Udc, with Udc*It makes the difference, obtains error signal e rr, obtained by error iteration PI The watt current Q axis instruction for stablizing busbar voltage, obtains three-phase pressure stabilizing active command i by DQ/ABC coordinate system transformationwa、iwb、 iwc；
Step S5: three-phase obtained above is compensated into electric current ira、irb、ircWith three-phase pressure stabilizing active command iwa、iwb、iwcIt asks With as the given of inductive current control ring, make the difference to obtain error signal, error signal warp with three-phase output electric current ia, ib, ic P adjuster is crossed to control to obtain modulating wave；
Step S6: modulating wave and carrier phase angle obtain SPWM, and the pipe movement of driving power main circuit realizes three-phase not The control of balancing equipment.
In the above-mentioned technical solutions, ABC/DQ transformation uses positive sequence phase angle wt in the step S2, in DQ coordinate system, fundamental wave Positive sequence composition is DC component, and fundamental wave negative sequence, zero sequence and Resonance Wave Composition are entirely Alternating Component.
In the above-mentioned technical solutions, the three phase harmonic instruction ∑ iabc in the step S2 includes fundamental wave negative sequence composition, base Wave zero sequence composition and higher hamonic wave composition.
In the above-mentioned technical solutions, DC component removal calculates in the step S2, by the way of cumulative integral, extracts Then DC component out makes the difference with id, iq, obtain the Alternating Component in DQ axis, the specific implementation of cumulative integral:
Difference expression are as follows:
Wherein, N is sample frequency points corresponding with respect to fundamental wave, and x (i) is the instantaneous value of active axis or idle axis.
In the above-mentioned technical solutions, the internal mode controller control in the step S3 is as follows:
Wherein, GrIt (z) is internal mode controller, speciallykrFor amplitude rectification, zkFor phasing, S It (z) is low-pass filter.
In the above-mentioned technical solutions, in the step S4 error iteration PI algorithm iterative formula are as follows:
Wherein, ir(τ) is the output valve of the τ moment algorithm；E (τ) is the error sampled value at τ moment, and M is the rounding of τ/N Value.
This closed loop control method, it can be readily appreciated that easy to accomplish, changing violent occasion in fundamental wave load can still stablize It runs and ensures good compensation effect.
Detailed description of the invention
Fig. 1 is that the topological diagram of three-phase imbalance equipment in the present invention is intended to；
Fig. 2 is closed loop control method circuit diagram of the present invention.
Specific embodiment
To make the objectives, technical solutions, and advantages of the present invention more comprehensible, below in conjunction with attached drawing and specific embodiment party Formula, the present invention is further described in detail.It should be understood that the specific embodiments described herein are only to solve The present invention is released, and the scope of protection of the present invention is not limited.
It please refers to shown in Fig. 1 and Fig. 2, a kind of closed loop of the three-phase imbalance equipment based on internal model principle and error iteration PI Control method, wherein three-phase imbalance equipment topological diagram: using two traditional level voltage type converter topologies, and exchange side is logical It crosses three pole reactor to be directly connected to power grid, DC side is using the capacitor series connection of two groups of divisions, and the midpoint of two groups of capacitors is as middle line It is connect with power grid N line, as zero sequence access.Wherein is is power network current, and ic is that equipment exports electric current, and Udc is DC bus electricity Pressure.
Implement to control by following steps:
Step S1, sampling three-phase network voltage obtains the angle wt of network voltage using phaselocked loop, as control transformation Phase angle foundation.
Step S2, acquisition power network current isa, isb, isc obtains the electric current of two axis of D, Q using ABC/DQ coordinate transform Ingredient id, iq.
Because of the fundamental wave and Resonance Wave Composition in addition to fundamental positive sequence electric current of three-phase imbalance equipment replacement, at this time ABC/DQ transformation need to use positive sequence phase angle wt, and in this way in DQ coordinate system, fundamental positive sequence composition is DC component, fundamental wave negative sequence, zero Sequence and Resonance Wave Composition are entirely Alternating Component.
And DC component removal is carried out to output id, iq of b and is calculated, obtain other electric currents without containing fundamental positive sequence Composition is converted using DQ/ABC coordinate system, obtains three phase harmonic instruction ∑ iabc, wherein including fundamental wave negative sequence composition, base Wave zero sequence composition and higher hamonic wave composition.
The composition of id, iq are described, so expecting that fundamental wave negative sequence, zero sequence and Resonance Wave Composition just need to reject Fall the DC component i.e. fundamental positive sequence composition in id, iq, DC component removal is calculated, by the way of cumulative integral, mentioned Take out DC component, then made the difference with id, iq, obtain Alternating Component in DQ axis namely fundamental wave negative sequence composition, fundamental wave zero sequence at Part and higher hamonic wave composition.
The specific implementation of cumulative integral:
Its difference expression are as follows:
Wherein N is sample frequency points corresponding with respect to fundamental wave, and x (i) is the instantaneous value of active axis or idle axis.
Step S3, it 0 is made the difference as given with three phase harmonic instruction ∑ iabc, error signal e rr is obtained, by internal model control Device controls to obtain three-phase compensation electric current ira、irb、irc。
Because being closed loop networking electric current, after compensation occurs, networking electric current can be gradually reduced, so necessary in closed-loop control There is the presence of internal mode controller, internal mode controller can guarantee still to keep the output of controller when input is 0.Internal model control Device processed and integral are similar to the effect of DC component, are the emphasis for realizing closed-loop control.
Internal model control is as follows:
Wherein Gr(z) it is internal mode controller, is speciallyTherein 0.98 is for internal mode controller Stablize.krFor amplitude rectification, zkFor phasing, S (z) is low-pass filter, and the main function of low-pass filter is to filter out height Subharmonic, the size that number can be compensated according to three-phase imbalance equipment highest determine the cutoff frequency of low-pass filter, low pass The form of filter is unlimited.For example the compensation of most high order is 13 subharmonic, then the cutoff frequency of low-pass filter may be selected by For the frequency more slightly higher than 13 times, such as 750Hz.This low-pass filter may insure that internal mode controller does not remove response excessively high frequency Harmonic wave or noise information.
Step S4, busbar voltage Udc is sampled, with Udc*It makes the difference, obtains error signal e rr, obtained by error iteration PI The watt current Q axis instruction for stablizing busbar voltage, obtains three-phase pressure stabilizing active command i by DQ/ABC coordinate system transformationwa、iwb、 iwc。
Error iteration PI can greatly enhance the dynamic and steady-state characteristic of busbar voltage control ring.
The iterative formula of error iteration PI algorithm are as follows:
Wherein, ir(τ) is the output valve of the τ moment algorithm；E (τ) is the error sampled value at τ moment, and M is the rounding of τ/N Value.
Step S5, the resulting three-phase of step S3 is compensated into electric current ira、irb、ircIt is active with the resulting three-phase pressure stabilizing of step S4 Instruct iwa、iwb、iwcIt sums as the given of inductive current control ring, makes the difference to obtain error with three-phase output electric current ia, ib, ic Signal, error signal control to obtain modulating wave by P adjuster.
Step S6, modulating wave and carrier phase angle, obtain SPWM, and the pipe movement of driving power main circuit realizes three-phase not The control of balancing equipment.
To sum up, the invention has the following advantages:
1. sampling current on line side carries out closed-loop control, control target is directly controlled, may be implemented to compensate well Effect；Possess current inner loop simultaneously, separation harmonic current control outer ring and busbar voltage control outer ring, it is ensured that the perseverance of busbar voltage It is fixed, greatly enhance the use scope of equipment.
2. harmonic current controls the controller that outer ring uses internal model principle, introduces DC component and remove link, it is ensured that 50Hz Fundamental active does not influence busbar voltage, while introducing the height that low-pass filter flexibly adjusts compensation number, internal mode controller Introducing greatly improve the tracking effect of harmonic wave.
3. busbar voltage ring introduces error iteration PI controller, the mistake of busbar voltage stable state control is greatly reduced Difference, while improving the response speed of busbar voltage ring in the case of fundamental active load sudden change, it is ensured that the peace of the voltage of bus Complete and compensation effect stability.This closed loop control method, it can be readily appreciated that it is easy to accomplish, change violent field in fundamental wave load Conjunction still with stable operation and can ensure good compensation effect.
Each technical characteristic of embodiment described above can be combined arbitrarily, for simplicity of description, not to above-mentioned reality It applies all possible combination of each technical characteristic in example to be all described, as long as however, the combination of these technical characteristics is not deposited In contradiction, all should be considered as described in this specification.
The embodiments described above only express several embodiments of the present invention, and the description thereof is more specific and detailed, but simultaneously It cannot therefore be construed as limiting the scope of the patent.It should be pointed out that coming for those of ordinary skill in the art It says, without departing from the inventive concept of the premise, various modifications and improvements can be made, these belong to protection of the invention Range.

Claims (6)

1. a kind of closed loop control method of the three-phase imbalance equipment based on internal model principle and error iteration PI, which is characterized in that It exchanges side in the topological diagram of three-phase imbalance equipment to be directly connected to by three pole reactor and power grid, DC side uses two groups of divisions Capacitor series connection, the midpoint of two groups of capacitors are connect as middle line with power grid N line, as zero sequence access, are realized by following steps Control:
Step S1: sampling three-phase network voltage obtains the angle wt of network voltage using phaselocked loop, the phase angle as control transformation Foundation；
Step S2: acquisition power network current isa, isb, isc obtain the current component of two axis of D, Q using ABC/DQ coordinate transform Id, iq, and DC component removal is carried out to id, iq and is calculated, obtain other current components without containing fundamental positive sequence, and benefit It is converted with DQ/ABC coordinate system, obtains three phase harmonic instruction ∑ iabc；
Step S3:0 makes the difference as given with three phase harmonic instruction ∑ iabc, error signal e rr is obtained, by internal mode controller control Three-phase compensation electric current i is madera、irb、irc；
Step S4: sampling busbar voltage Udc, with Udc*It makes the difference, obtains error signal e rr, obtain stablizing mother by error iteration PI The watt current Q axis of line voltage instructs, and obtains three-phase pressure stabilizing active command i by DQ/ABC coordinate system transformationwa、iwb、iwc；
Step S5: three-phase obtained above is compensated into electric current ira、irb、ircWith three-phase pressure stabilizing active command iwa、iwb、iwcSummation is made For the given of inductive current control ring, make the difference to obtain error signal with three-phase output electric current ia, ib, ic, error signal passes through P tune Section device controls to obtain modulating wave；
Step S6: modulating wave and carrier phase angle obtain SPWM, and three-phase imbalance is realized in the pipe movement of driving power main circuit The control of equipment.
2. closed loop control method according to claim 1, which is characterized in that ABC/DQ transformation is using just in the step S2 Sequence phase angle wt, in DQ coordinate system, fundamental positive sequence composition is DC component, and fundamental wave negative sequence, zero sequence and Resonance Wave Composition are entirely to hand over Flow composition.
3. closed loop control method according to claim 2, which is characterized in that the three phase harmonic in the step S2 instructs ∑ Iabc includes fundamental wave negative sequence composition, fundamental wave zero sequence composition and higher hamonic wave composition.
4. closed loop control method according to claim 3, which is characterized in that DC component removal meter in the step S2 It calculates, by the way of cumulative integral, extracts DC component, then made the difference with id, iq, obtain the Alternating Component in DQ axis, tire out The specific implementation of product integral:
Difference expression are as follows:
Wherein, N is sample frequency points corresponding with respect to fundamental wave, and x (i) is the instantaneous value of active axis or idle axis.
5. closed loop control method according to claim 1, which is characterized in that the internal mode controller control in the step S3 It is as follows:
Wherein, GrIt (z) is internal mode controller, speciallykrFor amplitude rectification, zkFor phasing, S (z) is Low-pass filter.
6. closed loop control method according to claim 1, which is characterized in that error iteration PI algorithm in the step S4 Iterative formula are as follows:
Wherein, ir(τ) is the output valve of the τ moment algorithm；E (τ) is the error sampled value at τ moment, and M is the rounding value of τ/N.
CN201810873309.XA 2018-08-03 2018-08-03 The closed loop control method of three-phase imbalance equipment based on internal model principle and error iteration PI Pending CN109004661A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109802397A (en) * 2019-01-03 2019-05-24 广州供电局有限公司 The adaptive PI double-closed-loop control method of static reactive generator
CN110829808A (en) * 2019-11-01 2020-02-21 中车永济电机有限公司 Current low-order harmonic suppression method for four-quadrant converter of electric locomotive
CN113852290A (en) * 2021-10-19 2021-12-28 山东华天电气有限公司 Real-time voltage steady-state error recovery control method and system

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109802397A (en) * 2019-01-03 2019-05-24 广州供电局有限公司 The adaptive PI double-closed-loop control method of static reactive generator
CN109802397B (en) * 2019-01-03 2020-11-27 广东电网有限责任公司广州供电局 Self-adaptive PI double closed-loop control method of static var generator
CN110829808A (en) * 2019-11-01 2020-02-21 中车永济电机有限公司 Current low-order harmonic suppression method for four-quadrant converter of electric locomotive
CN113852290A (en) * 2021-10-19 2021-12-28 山东华天电气有限公司 Real-time voltage steady-state error recovery control method and system
CN113852290B (en) * 2021-10-19 2023-08-08 山东华天电气有限公司 Real-time voltage steady-state error recovery control method and system

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Application publication date: 20181214