CN102522906B - Voltage balance and power balance control method of cascaded H bridge converter - Google Patents
Voltage balance and power balance control method of cascaded H bridge converter Download PDFInfo
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- CN102522906B CN102522906B CN201110434266.3A CN201110434266A CN102522906B CN 102522906 B CN102522906 B CN 102522906B CN 201110434266 A CN201110434266 A CN 201110434266A CN 102522906 B CN102522906 B CN 102522906B
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Abstract
The invention discloses a voltage balance and power balance control method of a cascaded H bridge converter. The method comprises the following steps: (1) double closed loop control used for providing a same modulated wave vector to each H bridge; (2) voltage balance control; and (3) power balance control, wherein the voltage balance control and the power balance control improve a modulated wave vector respectively, and a reconstructed modulated wave vector is obtained and is taken as a modulation signal of each H bridge. According to the invention, adding an extra circuit is not needed, compared with a method of directly modifying a modulation ratio, direct current side voltage of each H bridge maintains balanced, voltage ripple is basically consistent, each H bridge flows through active power distributed according to needs, reactive power is distributed according to equivalent, and the method has a wider constraint scope and is suitable for an occasion of large load unbalance.
Description
Technical field
The invention belongs to the applied technical field of high-voltage and high-power power electronic technology in electric power system, be specifically related to dc-voltage balance and the Power balance control method of Cascade H bridge converter.
Background technology
The Cascade H bridge converter belongs to multilevel converter, with clamp diode or clamp capacitor formula topological structure, compare, the degree of modularity is high, autgmentability is strong, be more suitable for, in the high-power occasion, in numerous high-power occasions such as high voltage converter, STATCOM, electric power electric transformer and photovoltaic combining inverters, obtaining a wide range of applications in recent years.
The Cascade H bridge converter can be divided into grid type and, from two kinds, net type, high voltage converter just belongs to from net type range of application, and its DC voltage relies on the individual independently DC source of N that electric energy is provided, and AC is commonly used to drive the equipment such as high-voltage motor, high-pressure hydraulic pump; Active filter, STATCOM, electric power electric transformer etc. belong to the application of typical grid type, and its AC directly is connected with electrical network after inductance, each H bridge DC side voltage mainly rely on and electrical network between Power Exchange foundation.Therefore, if there is parameter differences in each H bridge, or each DC side load exists when uneven, relies on traditional control method can't reach the purpose of dc-voltage balance.
Chinese patent CN1514525 by attachment device to carrying out the active power exchange between the Cascade H bridge, thereby realize that the balance of capacitance voltage controls, but this method need to increase extra device, has increased cost; Chinese patent CN1933274 and U.S. patent of invention US6075350 have proposed not increase the capacitance voltage balance method of attachment device, but their essence all is based on each H bridge the flow through variation of active power and the modulating wave variable quantity that difference obtains each H bridge, form the actual modulated ripple of each H bridge after on the initial modulation that is added to ripple; The power balancing method that Chinese patent CN101599708 is cascade multilevel inverter, but the power-balance of its indication is only active power distribution according to need, in fact just is balance of voltage problem; In this case, variation has occurred in the modulating wave vector of each H bridge only modulation ratio (modulating wave vector magnitude), and phase place still is consistent.They all take the balance of voltage as controlling target, only realized the balance of DC voltage, be active power distribution according to need, yet this has directly changed the reactive power of each H bridge, the reactive power that makes each H bridge share is different, cause each DC voltage ripple difference large, having a strong impact on the useful life of DC bus capacitor.
Summary of the invention
Goal of the invention: the problem and shortage existed for above-mentioned prior art, the balance of voltage and the Power balance control method that the purpose of this invention is to provide a kind of Cascade H bridge converter, without increasing extras, not only realized that dc-voltage balance, voltage ripple are consistent, make active power distribution according to need, reactive power equivalent is distributed simultaneously.
Technical scheme: for achieving the above object, the balance of voltage that the technical solution used in the present invention is a kind of Cascade H bridge converter and Power balance control method, comprise the steps: (1) two closed-loop controls, for giving each H bridge, provide identical modulating wave vector; (2) balance of voltage is controlled; (3) Power balance control; The described balance of voltage is controlled and Power balance control is improved modulating wave vector respectively, obtains modulating wave vector after the reconstruct modulation signal as each H bridge.
The described balance of voltage is controlled and can be comprised the steps:
(1) after each H bridge DC side voltage and DC voltage average are compared, carry out proportional plus integral control, obtain each H bridge modulation ratio correction factor;
(2) by each H bridge modulation ratio correction factor respectively with constant 1 addition, and be multiplied by the initial modulation wave vector that two closed-loop controls obtain, obtain the first modulating wave vector component.
Described Power balance control comprises the steps:
(1) amplitude of the initial modulation wave vector that the two closed-loop controls of calculating obtain obtains the initial modulation ratio;
(2) obtain the phase difference between current on line side vector initial modulation wave vector by phase-locked loop
and calculate
value;
(3) by each H bridge modulation ratio correction factor,
the product of value and initial modulation ratio, then be multiplied by the unit vector that hysteresis current on line side vector 90 is spent, obtain the second modulating wave vector component;
(4) respectively the first modulating wave vector component of each H bridge and the second modulating wave vector component are subtracted each other, obtain the modulating wave vector after the reconstruct of each H bridge.
Beneficial effect: (1) specific implementation is simple and convenient, and the power-balance circuit without the configuration additional complexity, only need some signal transducer and digit chips etc. cheaply;
(2) not only make each H bridge DC side voltage can balance, make voltage ripple to reach unanimity simultaneously;
(3) on active power demand assigned basis, make reactive power equivalent distribute, avoided distributing the inconsistent capacitance damage caused because of reactive power;
(4) the method has wider restriction range, and the linear modulation district is larger, is more suitable for the larger occasion of each H bridge DC side laod unbalance degree.
The accompanying drawing explanation
Fig. 1 is Cascade H bridge converter topology structure chart;
Fig. 2 is the balance of voltage and the power equalization stable state polar plot based on reconstruct modulating wave technology;
Fig. 3 is Cascade H bridge converter voltage balance and Power balance control Method And Principle figure;
The oscillogram that Fig. 4 obtains for the control method that adopts Chinese patent CN101599708, Fig. 4 (a) (uses U for each DC voltage
dcmean) oscillogram, Fig. 4 (b) (uses Q for each H bridge reactive power of flowing through
hmean) oscillogram;
Fig. 5 is for adopting the oscillogram that in the present invention, control method obtains, and Fig. 5 (a) (uses U for each DC voltage
dcmean) oscillogram, Fig. 5 (b) (uses Q for each H bridge reactive power of flowing through
hmean) oscillogram.
Embodiment
Below in conjunction with the drawings and specific embodiments, further illustrate the present invention, should understand these embodiment only is not used in and limits the scope of the invention for the present invention is described, after having read the present invention, those skilled in the art all fall within the application's claims limited range to the modification of the various equivalent form of values of the present invention.
The present invention is mainly used in the grid-connected control of Cascade H bridging parallel operation, extensive in applications such as Static Var Compensator, electric power electric transformers, now take the electric power electric transformer operating mode as example explanation the present invention.Figure 1 shows that Cascade H bridge topological structure, use R
ncarrying out each DC side load of equivalent Cascade H bridge, is the STATCOM operating mode during R=∞.According to this topological structure, can net side steady operation polar plot as shown in Figure 2.
According to H bridge linear modulation theory, can obtain
U
Hi＝U
dciD
i (1)
In formula (1), U
dcimean each H bridge DC side voltage, D
imodulating wave vector (being claims and specification summary of the invention described " the first modulating wave vector component ") for each H bridge; U
himean each H bridge AC voltage.
Therefore, for guaranteeing dc-voltage balance, i.e. U
dc1=U
dc2=...=U
dcn, in each H bridge parameter, in the inconsistent or inconsistent situation of DC side load, with identical initial modulation wave vector D, can't meet formula (1).
In Fig. 2, because of U
dcibe consistent, therefore U
hiavailable D
iequivalence.Modulating wave vector component on the current on line side direction can be expressed as active-power P; Component on the electric current vertical direction can be expressed as reactive power Q.As seen from the figure, the method for directly revising modulation ratio had both changed active power, had also changed reactive power simultaneously.
The present invention has introduced modulating wave vector error component Δ D
i(being claims and specification summary of the invention described " the second modulating wave vector component "), this component and current on line side vector
vertically, its size is relevant with the reactive power deviation of each H bridge.By this error component Δ D
iwith the modulating wave vector D after the modification modulation ratio
isuperpose and obtain the modulating wave vector after reconstruct, shown in (2).
In formula (2), D
i' be the modulating wave vector after reconstruct, m
ifor the modulation ratio correction factor; d
mmodulation ratio when not adding balancing control algorithm, the i.e. amplitude of initial modulation wave vector D;
for hysteresis current on line side vector
the unit vector of 90 degree;
for initial modulation ripple signal d and current on line side i
sbetween phase difference.
According to computing formula (2), can obtain specific implementation block diagram of the present invention as shown in Figure 3, concrete steps are as follows:
(1) DC voltage that each H bridge collects is asked for average, after comparing with given voltage, carries out proportional plus integral control, then obtains active current instruction i after being multiplied by the unit sine wave with the line voltage homophase
dref; Divided by corresponding coefficient, then obtain referenced reactive current i after being multiplied by the unit sine wave of hysteresis line voltage 90 degree after the reactive power instruction is directly artificial given
qref; By active current instruction i
drefwith referenced reactive current i
qrefobtain total instruction current i after addition
ref;
(2) total instruction current i
refsend into current regulator with actual current on line side, current regulator can be controlled for proportional integral (PI), also can control for ratio resonance (PR), adopts the Pl of feedforward with voltage to control here, obtains initial modulation ripple signal d;
(3) amplitude of calculating initial modulation ripple signal d obtains d
m;
(4) DC voltage of each H bridge and DC voltage average compare, and obtain the modulation ratio correction factor m of each H bridge after proportional plus integral control
i;
(5) initial modulation ripple signal d and current on line side i
sobtain the phase difference between them after phase-locked loop pll
and calculate
value;
(6) the value substitution formula (2) step (2)-(5) calculated, try to achieve respectively the first modulating wave vector component D
iwith the second modulating wave vector component Δ D
iafter, generate the modulating wave vector D after the reconstruct of each H bridge
i'.
Figure 4 shows that the oscillogram that the method that adopts Chinese patent CNl01599708 obtains, add this control method during 1s, from Fig. 4 (a), although DC voltage can balance, voltage ripple is different; As shown in Fig. 4 (b), each H bridge reactive power can't be balanced;
Figure 5 shows that the oscillogram that adopts control method of the present invention to obtain, add control method of the present invention during 1s, from Fig. 5 (a), DC voltage not only can balance, and voltage ripple reaches unanimity substantially; As shown in Fig. 5 (b), each H bridge reactive power can realize the equivalent distribution, has reached the purpose of power equalization.
Claims (1)
1. the balance of voltage of a Cascade H bridge converter and Power balance control method, is characterized in that, comprises the steps: (1) two closed-loop controls, for giving each H bridge, provides identical modulating wave vector; (2) balance of voltage is controlled; (3) Power balance control; The described balance of voltage is controlled and Power balance control is improved modulating wave vector respectively, obtains modulating wave vector after the reconstruct modulation signal as each H bridge;
Wherein, the described balance of voltage is controlled and is comprised the steps:
(1) after each H bridge DC side voltage and DC voltage average are compared, carry out proportional plus integral control, obtain each H bridge modulation ratio correction factor;
(2) by each H bridge modulation ratio correction factor respectively with constant 1 addition, and be multiplied by the initial modulation wave vector that two closed-loop controls obtain, obtain the first modulating wave vector component;
Described Power balance control comprises the steps:
(1) amplitude of the initial modulation wave vector that the two closed-loop controls of calculating obtain obtains the initial modulation ratio;
(2) obtain the phase difference between current on line side vector initial modulation wave vector by phase-locked loop
, and calculate
value;
(3) by each H bridge modulation ratio correction factor,
the product of value and initial modulation ratio, then be multiplied by the unit vector that hysteresis current on line side vector 90 is spent, obtain the second modulating wave vector component;
(4) respectively the first modulating wave vector component of each H bridge and the second modulating wave vector component are subtracted each other, obtain the modulating wave vector after the reconstruct of each H bridge.
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| CN103684011A (en) * | 2012-09-21 | 2014-03-26 | 成都市思博睿科技有限公司 | Diode clamping type hybrid cascaded bridge type frequency converter |
| BR112015032656A2 (en) | 2013-07-04 | 2017-07-25 | Abb Technology Ltd | method for controlling a chain link converter |
| CN104505844B (en) * | 2015-01-08 | 2017-01-11 | 国网上海市电力公司 | Cascaded STATCOM capacitor voltage balance control method based on active voltage vector reduplication |
| CN104578859B (en) * | 2015-01-19 | 2017-01-18 | 西安交通大学 | Voltage-sharing controlling method for direct current bus voltage of single-phase power electronic transformer |
| CN106533237B (en) * | 2016-12-07 | 2019-05-03 | 海华电子企业(中国)有限公司 | A kind of single-phase multi-module cascade H bridging parallel operation voltage balancing control method |
| CN108631628B (en) * | 2018-05-18 | 2020-10-16 | 南京铁道职业技术学院 | Capacitor voltage balance control method for H-bridge cascade rectifier |
| CN109521276A (en) * | 2018-10-19 | 2019-03-26 | 湖南大学 | A kind of high-voltage large-capacity impedance measurement device and its disturbance control method |
| CN110336479B (en) * | 2019-06-12 | 2020-06-30 | 合肥工业大学 | Reconstruction method for modulation wave of three-level NPC inverter switching device in online monitoring period |
| CN112072684B (en) * | 2020-09-11 | 2022-06-14 | 山东鲁软数字科技有限公司智慧能源分公司 | Power electronic transformer, control method and alternating current-direct current hybrid micro-grid charging system |
| CN112701658B (en) * | 2020-12-28 | 2021-09-21 | 东南大学 | Composite grounding device based on active inversion voltage regulation and small resistor |
| CN113394982B (en) * | 2021-06-23 | 2022-08-05 | 湘潭大学 | Transient voltage and power balancing method for cascaded H-bridge type power electronic transformer |
| CN116191629B (en) * | 2023-04-25 | 2023-07-11 | 西安奇点能源股份有限公司 | Interphase SOC balance control method and system for cascade H-bridge energy storage system |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1933274A (en) * | 2006-09-30 | 2007-03-21 | 中国科学院电工研究所 | H bridge cascade active electric filter DC side capacitance-voltage equalizing controlling maethod |
| CN101599708A (en) * | 2009-06-26 | 2009-12-09 | 华中科技大学 | The method for controlling power balance of DC side of cascaded multilevel inverter |
| CN101951178A (en) * | 2010-09-20 | 2011-01-19 | 清华大学 | Method used for balancing three phases of direct current side voltages of chain power regulating device |
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| JP5537235B2 (en) * | 2010-04-13 | 2014-07-02 | 株式会社日立製作所 | Power converter |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1933274A (en) * | 2006-09-30 | 2007-03-21 | 中国科学院电工研究所 | H bridge cascade active electric filter DC side capacitance-voltage equalizing controlling maethod |
| CN101599708A (en) * | 2009-06-26 | 2009-12-09 | 华中科技大学 | The method for controlling power balance of DC side of cascaded multilevel inverter |
| CN101951178A (en) * | 2010-09-20 | 2011-01-19 | 清华大学 | Method used for balancing three phases of direct current side voltages of chain power regulating device |
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| Title |
|---|
| JP特开2011-223784A 2011.11.04 |
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