CN103595278A - Power balance resonance control method for solar power generation system grid-side converter - Google Patents
Power balance resonance control method for solar power generation system grid-side converter Download PDFInfo
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- CN103595278A CN103595278A CN201310575597.8A CN201310575597A CN103595278A CN 103595278 A CN103595278 A CN 103595278A CN 201310575597 A CN201310575597 A CN 201310575597A CN 103595278 A CN103595278 A CN 103595278A
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Abstract
The invention discloses a power balance resonance control method for a solar power generation system grid-side converter. According to the technical scheme, the resonance control method for the solar power generation system grid-side converter under the condition of voltage imbalance of a power grid comprises eight main steps, the particular control process and implementation method of each step are provided, after the finally obtained reference voltage is modulated through a space vector, an obtained corresponding switch position signal serves as a switch signal of a power controlling device, and power balance resonance control over the grid-side converter is achieved. When the voltage of the power grid is unbalanced, the control method does not include conversion of rotational coordinates and decomposition calculation of positive and negative sequences, can effectively keep power balance at the side of the grid-side converter, suppresses the voltage fluctuation of a direct current bus, guarantees the sine degree of the current of the power grid, and improves the running capacity of the solar power generation system grid-side converter under the condition of voltage imbalance of the power grid.
Description
Technical field
The present invention relates to a kind of solar power system grid side converter power-balance resonance control method, belong to electric and electronic power converting means control field.
Background technology
When unbalanced source voltage, in solar power system, the power output of grid side converter occurs that fluctuation, output current distort, DC bus-bar voltage produces two frequency multiplication pulsation, and this will affect the running status of solar power system.Existing solution is to adopt symmetrical component theory to carry out positive and negative order decomposition to system, and sets up respectively corresponding positive and negative order current inner loop control structure.The method need to be carried out positive and negative order decomposition operation and rotating coordinate transformation in current inner loop, and this will increase the complexity of controller, reduces the dynamic response of system.In addition, by electrical network input power, asked for the method for positive and negative order current reference value, the method can obtain comparatively stable input power, but owing to not considering the impact of converter filter reactance, grid side converter power output and DC bus-bar voltage will there will be two frequency multiplication fluctuations.
Therefore, be necessary to design a kind of solar power system grid side converter power-balance resonance control method, under unbalanced source voltage condition, control method does not need positive-negative sequence decomposition operation and rotating coordinate transformation, by control change device side power-balance, suppress DC bus-bar voltage pulsation, keep output current sinusoidal, guarantee the control quality of solar power system.
Summary of the invention
The technical problem that the present invention solves has been to provide a kind of solar power system grid side converter power-balance resonance control method, the method can control change device side power-balance, suppress direct voltage two frequency multiplication pulsation, guarantee the sinusoidal degree of electric current, effectively reduce current on line side harmonic wave, improve the control quality of solar power system grid side converter when unbalanced source voltage.
Technical scheme of the present invention is: solar power system grid side converter power-balance resonance control method, it is characterized in that comprising the following steps: (l), adopt voltage sensor and current sensor to detect respectively three phase network voltage, three phase network electric current and DC voltage; (2) the three phase network voltage, step (l) being detected and three phase network electric current obtain line voltage and the power network current under two-phase rest frame through abc/ α β conversion module; (3) line voltage under the two-phase rest frame, step (2) being calculated obtains line voltage retardation through signal delay; (4), DC voltage that direct voltage reference value and step (1) are obtained subtracts each other, difference is multiplied each other and obtains grid side converter active power reference value with direct voltage reference value again after PI controller; (5), the active power reference value that obtains of the line voltage retardation that obtains of the line voltage that obtained by step (2) and step (3) and step (4), according to reference current calculating formula, obtain reference current; (6) it is poor that the power network current, under the two-phase rest frame that obtains with reference to electric current and step (2) is done, by difference through ratio resonant controller, controlled device output voltage; (7), according to reference voltage calculating formula, according to controller output voltage acquisition reference voltage; (8), the reference voltage that obtains by step (7), through space vector modulation SVM, obtain switch position signal as the switching signal of power ratio control device.
As further execution mode, the reference current calculating formula described in step (5) is as follows:
In formula,
,
.
Control method of the present invention is under unbalanced source voltage condition, by control change device side power-balance, guarantee that DC bus-bar voltage is stable, current on line side is sinusoidal, whole control procedure is based on two-phase rest frame, avoided rotating coordinate transformation, control method does not comprise positive-negative sequence and decomposes and phase-locked link, control structure is simple, and amount of calculation is less.
Accompanying drawing explanation
Fig. 1 is solar power system structure chart, the schematic diagram that Fig. 2 is control method of the present invention, and Fig. 3 is converter output current wave figure while adopting control method of the present invention, Fig. 4 is for adopting the DC bus-bar voltage oscillogram of control method of the present invention.
specific implementation method
Below in conjunction with accompanying drawing, the present invention will be further described.Solar power system structure as shown in Figure 1, solar array is connected with electrical network with step-up transformer through filter reactor by dc-dc converter, DC bus, grid side converter, and the output current of grid side converter has directly determined to output to the current harmonic content of electrical network.
The Mathematical Modeling of grid side converter under the static alpha-beta coordinate system of two-phase is
In formula,
u g α,
u g βbe respectively α, the beta-axis component of line voltage;
u c α,
u c βbe respectively α, the beta-axis component of converter output voltage;
i g α,
i g βbe respectively α, the beta-axis component of power network current;
l g,
r gbe respectively reactor inductance value and circuit equivalent resistance.
Retardation after 90 ° of line voltage under the static alpha-beta coordinate system of two-phase, converter output voltage, power network current and each self-dalays can be expressed as
，
(3)
In formula,
u g α,
u g βbe respectively α, the beta-axis component amplitude of line voltage;
u c α,
u c βbe respectively α, the beta-axis component amplitude of converter output voltage;
i g α,
i g βbe respectively α, the beta-axis component amplitude of power network current;
θ 1~
θ 6be respectively corresponding initial phase angle; Subscript " ' " represents the retardation of each variable;
ωfor line voltage angular frequency.
Converter active power of output
p cand reactive power
q cfor
Simultaneous formula (3) ~ formula (5)
In formula, first and second is respectively grid side converter active power of output DC component
and second harmonic component
.
Simultaneous formula (3), formula (4) and formula (6) can obtain
Wherein
In like manner, can obtain the DC component of grid side converter output reactive power
with second harmonic component
for
(9)
Wherein
Fig. 2 is solar power system grid side converter power-balance resonance control method schematic diagram.In figure,
u ga(
t),
u gb(
t),
u gc(
t) be respectively the line voltage under three phase static coordinate system;
u ca(
t),
u cb(
t),
u cc(
t) be respectively the photovoltaic DC-to-AC converter output voltage under three phase static coordinate system;
i ga(
t),
i gb(
t),
i gc(
t) be respectively the power network current under three phase static coordinate system;
u dc(
t) be DC bus-bar voltage;
p *(
t) be active power reference value;
cfor DC bus capacitor.Outer voltage adopts PI controller to direct voltage
u dc(
t) regulate, and provide reference power for current regulator
p *(
t).
According to formula (1), adoption rate resonance is controlled principle, and convertor controls reference voltage can be designed to
Its middle controller output voltage can be expressed as
In formula, subscript "
*" expression reference value;
k pr,
k irbe respectively ratio, the resonance coefficient of ratio resonant controller.
It is according to grid side converter power output equilibrium principle computing reference electric current that power-balance resonance of the present invention is controlled.In order to suppress direct voltage two frequency multiplication pulsation, reduce power network current distortion, during computing reference electric current, need consider that converter active power of output DC component is constant, harmonic component is zero, control reactive power DC component simultaneously and be zero and guarantee grid side converter unity power factor,
From formula (7), for making
can make
.
By formula (7), formula (9), can be obtained with formula (13)
Solve above formula and obtain reference current
,
with reference current retardation
,
be respectively
(15)
Wherein,
.
Because converter output voltage exists a large amount of switch harmonic, there is larger error in the reference current being calculated by formula (15).For fear of converter output voltage is carried out to Delay computing, reduce the reference current error of calculation, the retardation of converter output voltage is calculated by line voltage retardation and power network current, due to the equivalent resistance on filter reactor
r gresistance is very little, can ignore.According to formula (1) ~ formula (4), and replace power network current with reference current, converter output voltage and retardation thereof can be expressed as
，
(17)
By formula (14) ~ formula (17), obtained
In formula,
,
.
By formula (18) substitution formula (15), can obtain
In formula,
.
From formula (19), can be in the hope of reference current according to the inductance value of line voltage, line voltage retardation and filter reactor.During unbalanced source voltage, ratio resonance that the formula (19) of take is basic engineering is controlled the active power pulsation of having considered that net side and filter reactor are total, guarantees converter active power of output balance, thus inhibition DC voltage ripple.
Reference current substitution formula (11) by formula (19), obtains the reference voltage under two-phase rest frame, and this voltage signal, after space vector pulse width modulation, produces the switching signal of power ratio control device.
According to above analysis, the control method of solar power system grid side converter specifically comprises the steps:
(l), adopt voltage sensor and current sensor to detect respectively three phase network voltage
u ga(
t),
u gb(
t),
u gc(
t), three phase network electric current
i ga(
t),
i gb(
t),
i gc(
t) and DC voltage
u dc(
t);
(2) the three phase network voltage, step (l) being detected
u ga(
t),
u gb(
t),
u gc(
t) and three phase network electric current
i ga(
t),
i gb(
t),
i gc(
t) through abc/ α β conversion module, obtain the line voltage under two-phase rest frame
u g α(
t),
u g β(
t) and power network current
i g α(
t),
i g β(
t);
(3) line voltage under the two-phase rest frame, step (2) being calculated
u g α(
t),
u g β(
t) through signal delay, obtain line voltage retardation
u ' g α(
t),
u ' g β(
t);
(4), by direct voltage reference value
u * dc(
t) DC voltage that obtains with step (1)
u dc(
t) result of subtracting each other, after PI controller again with direct voltage reference value
u * dc(
t) multiplying each other obtains grid side converter active power reference value
p * (
t);
(5) line voltage, being obtained by step (2)
u g α(
t),
u g β(
t) and the line voltage retardation that obtains of step (3)
u ' g α(
t),
u ' g β(
t) and the active power reference value that obtains of step (4)
p * (
t), according to reference current calculating formula, obtain reference current
i * g α(
t),
i * g β(
t);
(6), with reference to electric current
i * g α(
t),
i * g β(
t) power network current under the two-phase rest frame that obtains with step (2)
i g α(
t),
i g β(
t) do poor, by difference through ratio resonant controller, controlled device output voltage
v g α(
t),
v g β(
t);
(7), according to reference voltage calculating formula, according to controller output voltage acquisition reference voltage
u * c α(
t),
u * c β(
t);
(8), the reference voltage that obtains by step (7), through space vector modulation SVM, obtain switch position signal as the switching signal of power ratio control device.
As further execution mode, the reference current calculating formula described in step (5) is as follows:
In formula,
,
.
Fig. 3, for adopting the power network current oscillogram of control method of the present invention, as seen from Figure 3, adopts control algolithm of the present invention, and the sinusoidal degree of electrical network three-phase current is better, and harmonic content is suppressed preferably.
Fig. 4 is for adopting the DC voltage oscillogram of control method of the present invention, as can be seen from Figure, when unbalanced source voltage, DC bus-bar voltage two frequency multiplication pulsation are less, control method of the present invention can, in unbalanced source voltage situation, obtain stable DC bus-bar voltage.
In sum, control method of the present invention can effectively suppress DC bus-bar voltage pulsation under unbalanced electric grid voltage, reduces three-phase current distortion, has strengthened the serviceability of solar power system grid side converter, and simple in structure, and amount of calculation is little.
Claims (2)
1. solar power system grid side converter power-balance resonance control method, is characterized in that comprising the following steps:
(l), adopt voltage sensor and current sensor to detect respectively three phase network voltage, three phase network electric current and DC voltage; (2) the three phase network voltage, step (l) being detected and three phase network electric current obtain line voltage and the power network current under two-phase rest frame through abc/ α β conversion module; (3) line voltage under the two-phase rest frame, step (2) being calculated obtains line voltage retardation through signal delay; (4), DC voltage that direct voltage reference value and step (1) are obtained subtracts each other, difference is multiplied each other and obtains grid side converter active power reference value with direct voltage reference value again after PI controller; (5), the active power reference value that obtains of the line voltage retardation that obtains of the line voltage that obtained by step (2) and step (3) and step (4), according to reference current calculating formula, obtain reference current; (6) it is poor that the power network current, under the two-phase rest frame that obtains with reference to electric current and step (2) is done, by difference through ratio resonant controller, controlled device output voltage; (7), according to reference voltage calculating formula, according to controller output voltage acquisition reference voltage; (8), the reference voltage that obtains by step (7), through space vector modulation SVM, obtain switch position signal as the switching signal of power ratio control device.
2. solar power system grid side converter power-balance resonance control method according to claim 1, is characterized in that the reference current calculating formula described in step (5) is as follows:
In formula,
,
.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106130387A (en) * | 2016-06-27 | 2016-11-16 | 国网江苏省电力公司常州供电公司 | Grid-connected inverters control method containing LCL filter |
| CN107104458A (en) * | 2017-04-21 | 2017-08-29 | 句容市宝启电子科技有限公司 | A kind of parallel network reverse distributed generation system of solar energy |
| WO2020019550A1 (en) * | 2018-07-25 | 2020-01-30 | 南京邮电大学 | Multi-synchronous rotating coordinate system-based multi-function grid-connected inverter harmonic control method |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101895128A (en) * | 2010-07-02 | 2010-11-24 | 国网电力科学研究院 | Control method of voltage fluctuation feedback of grid-connected current transformer under asymmetric voltage |
| CN101951174A (en) * | 2010-09-11 | 2011-01-19 | 天津大学 | Constant-frequency direct power control method for PWM converter under condition of power grid voltage imbalance |
| CN102035416A (en) * | 2010-12-14 | 2011-04-27 | 北京理工大学 | Method for controlling power equipartition of input-series output-series high-frequency link inverters |
| KR101047391B1 (en) * | 2011-05-02 | 2011-07-07 | 신우전원기술 주식회사 | Unbalance output voltage controller for three phase space vector pulse width modulated inverte |
| CN102593851A (en) * | 2012-02-10 | 2012-07-18 | 北方工业大学 | PWM rectifier control method under unbalanced power grid voltage based on power instruction compensation |
| CN102684465A (en) * | 2012-04-28 | 2012-09-19 | 北方工业大学 | Pulse-width modulation (PWM) rectifier control method based on current instruction generation in case of power grid imbalance |
| CN103515955A (en) * | 2013-09-27 | 2014-01-15 | 天津大学 | Deadbeat power control method for grid-side converter under network voltage unbalance |
-
2013
- 2013-11-18 CN CN201310575597.8A patent/CN103595278A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101895128A (en) * | 2010-07-02 | 2010-11-24 | 国网电力科学研究院 | Control method of voltage fluctuation feedback of grid-connected current transformer under asymmetric voltage |
| CN101951174A (en) * | 2010-09-11 | 2011-01-19 | 天津大学 | Constant-frequency direct power control method for PWM converter under condition of power grid voltage imbalance |
| CN102035416A (en) * | 2010-12-14 | 2011-04-27 | 北京理工大学 | Method for controlling power equipartition of input-series output-series high-frequency link inverters |
| KR101047391B1 (en) * | 2011-05-02 | 2011-07-07 | 신우전원기술 주식회사 | Unbalance output voltage controller for three phase space vector pulse width modulated inverte |
| CN102593851A (en) * | 2012-02-10 | 2012-07-18 | 北方工业大学 | PWM rectifier control method under unbalanced power grid voltage based on power instruction compensation |
| CN102684465A (en) * | 2012-04-28 | 2012-09-19 | 北方工业大学 | Pulse-width modulation (PWM) rectifier control method based on current instruction generation in case of power grid imbalance |
| CN103515955A (en) * | 2013-09-27 | 2014-01-15 | 天津大学 | Deadbeat power control method for grid-side converter under network voltage unbalance |
Non-Patent Citations (1)
| Title |
|---|
| 王继东等: "三相光伏并网Z-源逆变器的比例谐振控制", 《电机与控制学报》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106130387A (en) * | 2016-06-27 | 2016-11-16 | 国网江苏省电力公司常州供电公司 | Grid-connected inverters control method containing LCL filter |
| CN106130387B (en) * | 2016-06-27 | 2018-10-30 | 国网江苏省电力公司常州供电公司 | Grid-connected inverters control method containing LCL filter |
| CN109378988A (en) * | 2016-06-27 | 2019-02-22 | 国网江苏省电力公司常州供电公司 | A kind of grid-connected inverters control method containing LCL filter |
| CN109378988B (en) * | 2016-06-27 | 2020-05-19 | 国网江苏省电力公司常州供电公司 | Inverter grid-connected control method containing LCL filter |
| CN107104458A (en) * | 2017-04-21 | 2017-08-29 | 句容市宝启电子科技有限公司 | A kind of parallel network reverse distributed generation system of solar energy |
| WO2020019550A1 (en) * | 2018-07-25 | 2020-01-30 | 南京邮电大学 | Multi-synchronous rotating coordinate system-based multi-function grid-connected inverter harmonic control method |
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Application publication date: 20140219 |