CN102437587B - Island detection method of high-power photovoltaic grid-connected converter - Google Patents
Island detection method of high-power photovoltaic grid-connected converter Download PDFInfo
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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
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- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
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- Y02E10/56—Power conversion systems, e.g. maximum power point trackers
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Abstract
The invention discloses an island detection method of a high-power photovoltaic grid-connected converter. The method comprises the following steps of: determining whether a system operates at a grid-connected power generation state, and starting up an island detection algorithm instantly if the system is at the grid-connected power generation state; detecting whether the frequency of the voltage of a port power grid is within the normal range in real time, if the frequency is not within the normal range, considering that the system is at the island state, and carrying out automatic safety stop on the system; adding reactive current Iqdisturb with the duration of td periodically within the normal range; and superposing the reactive current Iqdisturb and reactive control Icqset of the converter, thus an axis q component reference Icqref of grid-connected current of the converter is formed finally. The contradiction between two aspects of reliability of detection and the quality after grid-connected electric energy reduction for the traditional island detection algorithm is effectively solved by the method provided by the invention, and the implementation method is simple and effective.
Description
Technical field
The present invention relates to a kind of island detection method, particularly a kind of island detection method of high-power photovoltaic synchronization current transformer, belongs to photovoltaic generating system control technology application.
Background technology
Distribution of solar energy is extensive, is easy to as people utilize, and in numerous new forms of energy, solar energy forms the focus of paying attention to into people with its exclusive advantage.The development and utilization of solar energy, by contributing to the mankind progressively to break away from the dependence to traditional energy, is gone on the road of sustainable development, has important strategic importance.
Along with utilizing grid-connected photovoltaic system capacity and the quantity of solar energy constantly to increase, also day more highlights the isolated island problem of generation.Electric power isolated island may bring following harm: on the one hand, because power network switch disconnects, electrical network maintenance personal thinks that circuit is safe by mistake, thereby will its life be produced safely to larger threat; Meanwhile, can affect the operation program of protection switch in distribution system, impact electric network protection device; On the other hand, the supply power voltage in electric power isolated island region and frequency, by unstable, also can cause system threephase load to owe to power mutually for single-phase distributed generation system, may cause the undesired even damage of power consumption equipment; In addition, when mains supply recovers, unavoidably there is difference in magnitude or phase difference in line voltage and photovoltaic generating system port voltage, will cause larger grid-connected impulse current.
Method for detection of isolated island problem is divided into passive detection method and active detecting method, the principle that wherein passive isolated island detects is the grid-connected port voltage by real-time detecting system, the relevant parameter of grid-connected current, as amplitude, frequency, harmonic wave, negative phase-sequence etc., judge its whether overrun as photovoltaic system the foundation in islet operation state whether; Initiatively island detection method is by add certain interference in system, as meritorious/reactive current disturbance, frequency disturbance, negative phase-sequence and harmonic disturbance etc.When electrical network is normal, this disturbance is on almost not impact of port voltage, and under island state, and this disturbance will cause the port voltage amplitude, frequency, harmonic wave, negative phase-sequence etc. of system to change, until overrun represents that island state is detected effectively.But above-mentioned various detection method is both advantageous and disadvantageous, conventionally need to take several diverse ways to carry out comprehensively, complementing each other.Comprehensive, the isolated island of high-power photovoltaic synchronization electricity generation system detects needs to meet following requirement:
(1) when electrical network trips because of a variety of causes, system should be able to quickly and reliably detect isolated island.On the one hand, the leading indicator of rapidity be exactly at power network switch tripping 2s with interior (with reference to < < 400V following low-pressure grid-connection photovoltaic generation special inverter specification requirement and test method > >), island state will successfully be detected; On the other hand, reliability mainly refers to is exactly no matter local load is pure resistive, idle or be harmonic load etc., and algorithm all should be able to correctly detect isolated island.
(2) when electrical network normally moves, the disturbance that initiatively isolated island detection algorithm injects reduces as much as possible on the also impact of network electric energy quality, especially when port voltage is subject to the switching of local load, during the variation of amplitude, frequency or the phase place that the problem of circuit delivery of electrical energy causes, isolated island detection algorithm can not be judged as island state by it by mistake.
(3) detection algorithm can not cause the significant change of active power, in order to avoid the adjustment of power tracking algorithm (MPPT) direction of search that has the greatest impact.
Therefore, how to guarantee the reliability that isolated island detects simultaneously and reduce as much as possible on and the impact of network electric energy quality be the Focal point and difficult point of island detection method design.
Summary of the invention
The object of the invention just overcoming above-mentioned the deficiencies in the prior art, provide a kind of simply, reliably, island detection method fast, the method is applied in high-power photovoltaic synchronization current transformer, when can guarantee that island state is detected quickly and accurately, reduce as much as possible the also impact of network electric energy quality.
The technical scheme that realizes the object of the invention employing is a kind of island detection method of high-power photovoltaic synchronization current transformer, comprises the following steps:
Step (1), in grid-connected 3-phase power converter, real-time lock mains frequency f and positive sequence phase angle theta;
Step (2), judges whether system works in the state of generating electricity by way of merging two or more grid systems, if system, in the state of generating electricity by way of merging two or more grid systems, starts isolated island detection algorithm immediately;
Step (3), between the isolated island detection algorithm starting period, in real time the frequency of detection port line voltage, whether within normal scope, is greater than minimum tolerance frequency f
minand be less than maximum tolerance frequency f
max;
Step (4), if line voltage frequency overrun thinks that system is in island state, system protection is shut down;
Step (5) is t if port voltage frequency in normal range (NR), periodically adds the duration
dreactive current disturbance, the size of this disturbance quantity during according to a upper disturbance end cycle frequency of port voltage and the deviation delta f of specified mains frequency decide:
If a) this deviation is within certain scope, be greater than minimum tolerance frequency deviation delta f
minand be less than maximum tolerance frequency deviation delta f
max, the reactive current disturbance quantity of injecting is initial value-I
qp0;
B) if frequency departure surpasses above-mentioned scope, introduce positive feedback, the computing formula of the reactive current disturbance quantity of this cycle injection is: I
qdisturb=-I
qp0-K Δ f, wherein K is positive feedback coefficient;
C) at cycle period, in the remaining time, cancel the injection of reactive current disturbance.
Step (6), the reactive current disturbance I that abovementioned steps is obtained
qdisturb, with the given I of the idle control of current transformer
cqsetsuperimposed, finally form the q axle component of current transformer grid-connected current with reference to I
cqref.
Further, in described step (1), be by adopting the software phase-lock loop (SPLL) based on digital delay signal cancellation algorithm (DSC) to come real-time lock mains frequency f and positive sequence phase angle theta by the three-phase voltage U a of electrical network, Ub, Uc.
Further, said method is to carry out in digital signal processor.
Technique scheme of the present invention has the following advantages compared to existing technology:
(1) compare with adopting active current disturbance, in grid-connected current, injecting reactive current disturbance can not cause the larger variation of system active power, is conducive to the power stability of system, has solved active current method of perturbation and the afoul contradiction of MPPT algorithm.
(2) under island state, compare with the method that causes port voltage amplitude to change, what this method changed is the frequency of port voltage, all comparatively favourable to the fail safe of photovoltaic system equipment and local load.For example port voltage amplitude will change the foundation that more than 20% could occur as isolated island conventionally, and this voltage likely produces infringement to the switch of photovoltaic DC-to-AC converter, local power consumption equipment etc.; And port frequency changes the foundation that 1Hz just can be used as isolated island generation conventionally, this frequency change is conventionally all within the allowed band of most of power consumption equipment.
(3) fixedly disturbance injection method needs larger disturbance injection rate, the reliability of guarantee detection algorithm, and the positive feedback algorithm that the present invention adopts, can be in the situation that less disturbance initial value, the effect producing according to disturbance determines whether adding positive feedback, under island state, once positive feedback is activated, the frequency of port voltage will depart from normal range (NR) fast, guarantee rapidity and the reliability of detection method.
Accompanying drawing explanation
Fig. 1 is the structural representation of grid-connected photovoltaic power generation system;
Fig. 2 is the flow chart of island detection method of the present invention;
When Fig. 3 is the local resonant load of the grid-connected current transformer band of 250kW, use the effect schematic diagram of island detection method of the present invention.
Embodiment
For content of the present invention is more easily expressly understood, below according to a particular embodiment of the invention and by reference to the accompanying drawings, technical solution of the present invention is described in further detail.
It is example that the present embodiment be take a kind of 250kW parallel network power generation current transformer, and island detection method proposed by the invention and actual enforcement are described.As shown in Figure 2, the method realizes according to following steps in digital signal processor DSP:
Step (1), in grid-connected 3-phase power converter, by the three-phase voltage U a of electrical network, Ub, Uc, by employing, the software phase-lock loop (SPLL) based on digital delay signal cancellation algorithm (DSC) comes real-time lock mains frequency f and positive sequence phase angle theta;
Step (2), judges whether system works in the state of generating electricity by way of merging two or more grid systems, if system, in the state of generating electricity by way of merging two or more grid systems, starts isolated island detection algorithm immediately;
Step (3), between the isolated island detection algorithm starting period, in real time whether the frequency of detection port line voltage, whether within normal scope, is greater than minimum tolerance frequency f
minand be less than maximum tolerance frequency f
max;
Step (4), if line voltage frequency overrun thinks that system is in island state, system protection is shut down;
Step (5) is t if port voltage frequency in normal range (NR), periodically adds the duration
dreactive current disturbance, the size of this disturbance quantity during according to a upper disturbance end cycle frequency of port voltage and the deviation delta f of specified mains frequency decide:
If a) this deviation is within certain scope, be greater than minimum tolerance frequency deviation delta f
minand be less than maximum tolerance frequency deviation delta f
max, the reactive current disturbance quantity of injecting is initial value-I
qp0;
B) if frequency departure surpasses above-mentioned scope, introduce positive feedback, the computing formula of the reactive current disturbance quantity of this cycle injection is: I
qdisturb=-I
qp0-K Δ f, wherein K is positive feedback coefficient;
C) at cycle period, in the remaining time, cancel the injection of reactive current disturbance.
Step (6), the reactive current disturbance I that abovementioned steps is obtained
qdisturb, with the given I of the idle control of current transformer
cqsetsuperimposed, finally form the q axle component of current transformer grid-connected current with reference to I
cqref.
The inventive method effectively solve traditional isolated island detection algorithm the reliability detecting with reduce aspect these two of network electric energy qualities also as far as possible between contradiction.The present embodiment describes with the operational effect in the exemplary application at a 250kW parallel network power generation current transformer, as shown in Figure 3.While adopting the local resonant load of the grid-connected current transformer band of 250kW of island detection method of the present invention, by people, be that disjunction K2 simulates PCC is ordered while there is isolated island grid-connected voltage waveform and the disjunction control signal (representing disjunction for height) of electrical network section breaker K2, in Fig. 3,1 is grid-connected voltage, and 2 is the disjunction control signal of electrical network section breaker K2.In figure, the first half is normal waveform, and the latter half is the time of the first half to launch waveform.As seen from Figure 3; even if be with under local resonant load; when isolated island occurs; current transformer can detect rapidly and the grid-connected K switch 1 of disjunction (response time is in 0.15s; meet examination criteria requirement); realized reliable anti-island protect, and be less than respectively 1% and 2% in fully loaded total harmonic distortion that current transformer exchanges port voltage and electric current when grid-connected, on and network electric energy quality impact little.This detection method realizes simple, and reliability is higher, is highly suitable for practical application.
Obviously, above-described embodiment is only for example is clearly described, and the not restriction to execution mode.For those of ordinary skill in the field, can also make other changes in different forms according to varying in size of equipment on the basis of the above description.Here exhaustive without also giving all execution modes.And the apparent variation of being extended out thus or change are still among the protection range in the invention.
Claims (2)
1. an island detection method for high-power photovoltaic synchronization current transformer, is characterized in that, comprises the following steps:
Step (1), in grid-connected current transformer, to the three-phase voltage U a of electrical network, Ub, Uc, by employing, the software phase-lock loop based on digital delay signal cancellation algorithm comes real-time lock mains frequency f and positive sequence phase angle theta;
Step (2), judges whether system works in the state of generating electricity by way of merging two or more grid systems, if system in the state of generating electricity by way of merging two or more grid systems, starts isolated island immediately, detects;
Step (3), between the isolated island detection algorithm starting period, in real time whether the frequency of detection port line voltage, whether within normal scope, is greater than minimum tolerance frequency f
minand be less than maximum tolerance frequency f
max;
Step (4), if line voltage frequency not in above-mentioned normal range (NR), thinks that system is in island state, system protection is shut down;
Step (5) is t if port voltage frequency in above-mentioned normal range (NR), periodically adds the duration
dreactive current disturbance, the size of this disturbance quantity during according to a upper disturbance end cycle frequency of port voltage and the deviation delta f of specified mains frequency decide:
If a) this deviation delta f is within certain scope, be greater than minimum tolerance frequency deviation delta f
minand be less than maximum tolerance frequency deviation delta f
max, the reactive current disturbance quantity I injecting
qdisturbfor initial value-Iq
p0;
B), if frequency deviation f a) in described scope, does not introduce positive feedback in step, the computing formula of the reactive current disturbance quantity injected of this cycle is: I
qdisturb=-I
qp0-K Δ f, wherein K is positive feedback coefficient;
C) at cycle period, in the remaining time, cancel the injection of reactive current disturbance;
Step (6), the reactive current disturbance I that abovementioned steps is obtained
qdisturb, with the given I of the idle control of current transformer
cqsetsuperimposed, finally form the q axle component of current transformer grid-connected current with reference to I
cqref.
2. the island detection method of high-power photovoltaic synchronization current transformer according to claim 1, is characterized in that: said method is to carry out in digital signal processor.
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| CN108344902B (en) * | 2017-10-24 | 2021-06-29 | 广东电网有限责任公司汕头供电局 | Power loss judgment method and device for flexible direct current power transmission device facing inspection personnel |
| CN108445326B (en) * | 2018-04-02 | 2021-07-27 | 杭州康奋威科技股份有限公司 | Active reactive island detection method |
| CN108680822B (en) * | 2018-08-20 | 2021-01-26 | 金陵科技学院 | Self-adaptive island detection method and capacitive load judgment method thereof |
| CN109100616B (en) * | 2018-10-23 | 2020-10-09 | 上海正泰电源系统有限公司 | Method for detecting single-phase power failure of transformer with grounding |
| CN110488148B (en) * | 2019-07-30 | 2020-09-11 | 华为技术有限公司 | Islanding detection method and device and computer readable storage medium |
| CN111864795B (en) * | 2020-06-28 | 2022-04-22 | 天津大学 | MPPT trapezoidal voltage disturbance-based direct-current micro-grid island detection method |
| CN117805541B (en) * | 2024-02-29 | 2024-05-03 | 西安千帆翼数字能源技术有限公司 | Island detection method, protection method and related device of energy storage converter |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101944746A (en) * | 2010-07-20 | 2011-01-12 | 郑军 | Island detection method, device and system of photovoltaic grid-connected power generating system |
| CN102170141A (en) * | 2009-11-13 | 2011-08-31 | 伊顿公司 | Method and area electric power system detecting islanding by employing controlled reactive power injection by a number of inverters |
-
2011
- 2011-09-23 CN CN201110286662.6A patent/CN102437587B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102170141A (en) * | 2009-11-13 | 2011-08-31 | 伊顿公司 | Method and area electric power system detecting islanding by employing controlled reactive power injection by a number of inverters |
| CN101944746A (en) * | 2010-07-20 | 2011-01-12 | 郑军 | Island detection method, device and system of photovoltaic grid-connected power generating system |
Non-Patent Citations (6)
| Title |
|---|
| Analysis and performance assessment of the active frequency drift method of islanding prevention;M. E. Ropp et al;《IEEE Transactions on Energy Conversion》;19990930;第14卷(第3期);810-816 * |
| M. E. Ropp et al.Analysis and performance assessment of the active frequency drift method of islanding prevention.《IEEE Transactions on Energy Conversion》.1999,第14卷(第3期), |
| 三相并网逆变器的无功扰动孤岛检测技术研究;张王莹;《中国优秀硕士学位论文全文数据库 工程科技II辑》;20100731(第7期);10-14,36-41 * |
| 光伏并网系统反孤岛控制策略仿真分析;王志峰等;《通信电源技术》;20070325;第24卷(第2期);29-31 * |
| 张王莹.三相并网逆变器的无功扰动孤岛检测技术研究.《中国优秀硕士学位论文全文数据库 工程科技II辑》.2010,(第7期), |
| 王志峰等.光伏并网系统反孤岛控制策略仿真分析.《通信电源技术》.2007,第24卷(第2期), |
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