CN103955253B - Based on the photovoltaic array multimodal value maximum power point tracing method of power closed loop scanning - Google Patents
Based on the photovoltaic array multimodal value maximum power point tracing method of power closed loop scanning Download PDFInfo
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Abstract
The invention discloses a kind of photovoltaic array multimodal value MPPT maximum power point tracking (MPPT-Maximum Power Point Tracking) method based on the scanning of power closed loop.It is made up of three phases, and the first stage is the whole scan realizing multi-peak curve based on power closed-loop control, completes the location of maximum power point; Subordinate phase is 3 the collaborative variable step disturbance observation processes realized based on particle swarm optimization algorithm, realizes the Local Search near maximum power point; Phase III determines voltage steady track process, and simultaneously the judgement of environmentally change information, activates the process of first or subordinate phase.The present invention can both realize the MPPT maximum power point tracking of photovoltaic array under unimodal or multimodal situation, there is not disturbance observation method, the erroneous judgement of conductance increment method and oscillation problem; What can overcome the existence of existing method loses the problem more, dynamic process is slower by dynamic following function simultaneously.The present invention can find global maximum power point effectively, realizes quick, stable, the accurate tracking of maximum power point.
Description
Technical field
The invention belongs to the photovoltaic power generation technology in electrical engineering field, be specifically related to the MPPT maximum power point tracking of photovoltaic array under uneven illumination condition in a kind of photovoltaic generating system and control (MPPT-Maximum PowerPoint Tracking) method.
Background technology
Sun power, as a kind of regenerative resource, has widely distributed, sustainable, free of contamination advantage.Photovoltaic power generation technology is effective one of Basic Ways utilizing solar energy resources.At present, the support energetically that grid-connected various photovoltaic power generation technologies have received national governments is comprised.
Although photovoltaic power generation technology has a good application prospect, it is as a kind of newer technology, and being also faced with manyly has problem to be solved, and one of them is that photovoltaic array shade covers problem.The reason that shade covers problem is caused to have, photovoltaic cell towards, buildings partial occlusion and laying dust covering etc. different from inclination angle during inconsistent, the project installation of photovoltaic cell or photovoltaic module output characteristics own.When photovoltaic array covers by shade, the output characteristic curve of photovoltaic array will show multi-peak feature, and be now difficult to make photovoltaic array be operated in global maximum power point, the operational efficiency of photovoltaic generating system significantly declines; According to statistics, covering by shade the photovoltaic array efficiency decline caused can up to more than 15%.Maximum power point of photovoltaic array tracing control is the Basic Ways improving photovoltaic array generating efficiency, and cover under normal circumstances at shadow-free, the output characteristic curve of photovoltaic array is single peak curve, now than being easier to the maximum power point finding system.
In the recent period, conventional single peak maximum power point tracing method mainly comprises disturbance observation method, conductance increment method, constant voltage process and stagnant ring relative method etc.These methods are mainly applicable to the MPPT maximum power point tracking of photovoltaic system under single peak condition, and for being covered the multi-peak situation caused by shade, existing single peak maximum power point tracing method is difficult to adapt to.Therefore, design the maximum power point tracing method that simultaneously can be applicable to single peak and multi-peak situation and there is outstanding engineering significance.
At present, under multi-peak condition, the tracking and controlling method of maximum power point has become the study hotspot problem of photovoltaic power generation technology, this existing scientific paper has done deep theoretical analysis to this, also the engineering method of practical application is had, as application for a patent for invention " photovoltaic array multimodal maximum power point tracing method " (CN103123514A) and " the quick optimization method of overall maximum power point of photovoltaic array under local shadow " (CN103324239A).Wherein,
Chinese invention patent application prospectus CN103123514A " photovoltaic array multimodal maximum power point tracing method " disclosed in 29 days Mays in 2013 first tentatively chooses global maximum power point (MPP) mountain peak, place according to the open-circuit voltage of photovoltaic array during shadow-free and short-circuit current; Again with the ratio of the voltage of maximum power point of photovoltaic array during shadow-free and tandem photovoltaic component count for benchmark, choose maximal power tracing (MPPT) step-size in search, search for the MPP of the left and right sides respectively, until search certain MPP, the output power value of its correspondence is greater than the MPP output power value of its left and right sides, namely thinks that this MPP is overall MPP; Finally maintain photovoltaic array and run on overall MPP, and the change of Real-Time Monitoring service condition, if service condition change, then restart multimodal MPPT strategy.But this tracking also exists following deficiency:
1) implementation procedure needs the numerous information depending on photovoltaic array: the component type in photovoltaic array open-circuit voltage during shadow-free, short-circuit current, photovoltaic array, assembly series connection number etc., specifically refer to described in its step 1, the environmental suitability that this defect determines the method is not strong;
2) adopt the scanning of voltage close loop control realization photovoltaic array output power curve, must could be determined the position of maximum power point by point by point scanning, the process that result in dynamic scan is too slow;
3) what the Local Search in the method adopted is " disturbance observation method " and " conductance increment method ", and these two kinds of methods also exist dynamic process erroneous judgement, steady track process oscillation problem among a small circle, cause the accuracy of its dynamic stability and stable state not high;
4) basic ideas of the method are as described in IEEE document " A Study on a Two StageMaximum Power Point Tracking Control of a Photovoltaic System underPartially Shaded Insolation Conditions " in 2003 (a kind of two benches maximum power tracking method research of photovoltaic system " in the partial occlusion situation "---IEEE energy science in 2003 can plenary session collection of thesis), it can make erroneous judgement under part situation, namely the foundation " selecting the scope of the existence of overall MPP " does not generally adapt to, the result judged is wrong sometimes,
5) do not provide the detection of environment dynamic change, Rule of judgment that MPPT method is restarted, namely algorithm is incomplete.
What Chinese invention patent application prospectus CN103324239A " the quick optimization method of overall maximum power point of photovoltaic array under local shadow " disclosed in 25 days September in 2013 adopted is that " revising fruit bat algorithm " realizes global search, " improving Golden Section method " completes Local Search.Its main not foot point existed comprises:
1) the global search strategy adopted---" revising fruit bat algorithm " is similar to " PSO algorithm ", it is all a kind of evolution algorithm, though it has when hyperspace optimizing, there is the advantage of fast convergence rate, but in the face of the extremum search problem of photovoltaic array P-V curve, the performance of its rapidity is not obvious, and the search performance simultaneously " revising fruit bat algorithm " depends on the selection of initial work location, there is the situation that can not converge to global maximum power point;
2) what adopt is voltage close loop search, its implementation procedure also must adopt point by point scanning process, in search procedure, the performance number of a lot of working point is much smaller than peak power power of operating point, so loss of active power is larger, also there is the repeatedly fluctuation problem of quiescent potential simultaneously;
3) do not provide the detection of environment dynamic change, Rule of judgment that MPPT method is restarted, algorithm is incomplete.
Summary of the invention
The technical problem to be solved in the present invention be strong for the environmental suitability existed in prior art, global search process power loss is more, global maximum power point is followed the tracks of unsuccessfully and power oscillation problem, there is provided a kind of can the global maximum power point traced under multi-peak situation of fast and stable, to improve the photovoltaic array multimodal value maximum power point tracing method based on the scanning of power closed loop of the generating efficiency of photovoltaic array.
For solving technical matters of the present invention, the technical scheme adopted is: the photovoltaic array multimodal value maximum power point tracing method based on the scanning of power closed loop comprises output voltage, the output current of on-line checkingi photovoltaic array, particularly,
Step 1, power closed-loop control scans: first by output voltage, the output current of on-line checkingi photovoltaic array, to obtain the real-time output power that photovoltaic array exports, the closed-loop control of recycling power makes real-time output power track reference power, thus obtains the control signal of MPPT maximum power point tracking circuit;
Does step 2, judge that photovoltaic array output voltage is less than the minimum operating voltage of photovoltaic DC-to-AC converter? proceed to step 3 when being less than, otherwise repeat step 1 and step 2;
Step 3, 3 collaborative variable step Local Searches: first based on the photovoltaic array peak power output of acquisition in step 1 and step 2 and the output voltage values of correspondence thereof, set three initial work location, recycling voltage close loop controls, photovoltaic array is made to work on three working points successively, utilize the photovoltaic array output voltage of on-line checkingi simultaneously, output current, obtain the output power of each working point, when MPPT maximum power point tracking end cycle, upgrade the peak power dot information of global maximum power point information and each working point experience, when three working points take turns to operate after one time, the information of three working points obtained is utilized jointly to determine the operating voltage of next round three working points,
Does according to the magnitude of voltage of three working points, step 4, judge that whether three working points enough close? if following condition: P
m≠ 0, U
m-U
m1< U
step/ 10, U
m-U
m2< U
step/ 10, U
m-U
m3< U
step/ 10 meet simultaneously, P wherein
mfor power, the U of known maximum power point
mfor voltage, the U of known maximum power point
m1, U
m2, U
m3be respectively magnitude of voltage, the U at the maximum power point place that three working points experience separately
stepfor initial disturbance step-length, then for enough close to and proceed to step 5, otherwise repeat above-mentioned steps 3 and step 4;
Step 5, determine voltage steady track: first utilize voltage close loop to control, on the maximum power point that the output voltage stabilization of photovoltaic array is determined in step 3, step 4, the photovoltaic array output voltage that recycling detects in real time and output current, calculate real-time output power, afterwards, the peak power output obtained by more real-time output power and step 3, step 4, calculates relative power variable quantity and accumulative relative power variable quantity;
Does step 6, based on relative power variable quantity, judge that environment there occurs acute variation? if so, then reboot step 1;
Does step 7, based on accumulative relative power variable quantity, judge that environment there occurs slow change? if so, then reboot step 3, otherwise proceed to step 5.
Further improvement as the photovoltaic array multimodal value maximum power point tracing method scanned based on power closed loop:
The process of the power closed-loop control in described step 1 is, after obtaining real-time output power each time, by the comparison of real-time output power and known global maximum power, upgrades global maximum power point information, even P=U
pv* I
pv> P
m, then U
m=U
pv, P
m=P, the P in formula is real-time output power, U
pvfor the photovoltaic array output voltage, the I that detect in real time
pvfor the photovoltaic array output current, the U that detect in real time
mfor voltage, the P of known maximum power point
mfor the power of known maximum power point.
Reference power in described step 1 is by formula P
r(k)=P
r(k-1)+P
stepdetermine, the P in formula
r(k) current reference power, P for following the tracks of
r(k-1) be the last reference power, the P that follow the tracks of
stepfor the step-length of reference power change.
Three initial work location in described step 3 are according to U
1(k)=U
m, U
2(k)=U
m-U
step, U
3(k)=U
m+ U
stepdetermine, U wherein
1k voltage, U that () is first job point
2k () is voltage, the U of second working point
3k () is voltage, the U of the 3rd working point
mfor voltage, the U of known maximum power point
stepfor initial disturbance step-length.
The operating voltage of next round three working points in described step 3 is determined according to following formula:
Δ U in formula
1(k), Δ U
2(k), Δ U
3k () is the voltage disturbance amount in three working point current MPPT maximum power point tracking cycles, Δ U
1(k-1), Δ U
2(k-1), Δ U
3(k-1) be the voltage disturbance amount in three working point previous MPPT maximum power point tracking cycles, U
m1, U
m2, U
m3be the maximum power point voltage value that three working points experience separately, U
1(k-1), U
2(k-1), U
3(k-1) be the voltage in three working point previous MPPT maximum power point tracking cycles, ω ∈ (0,1), c
1∈ (0,1), c
2∈ (0,1) is quiescent potential step-length regulating parameter.
Relative power variable quantity in described step 5 and accumulative relative power variable quantity are according to following formulae discovery: E
p=1-U
pv* I
pv/ P
m, E=Σ E
p, the E in formula
pfor the accumulative relative power variable quantity that the relative power variable quantity in current MPPT maximum power point tracking cycle, E are multiple tracking cycle.
During reboot step 1 in described step 6, value and power reference is according to P
r(k)=(U
pv* I
pv)/2 set, reset maximum power point power P simultaneously
m=0, the U in formula
pvfor the photovoltaic array output voltage, the I that detect in real time
pvfor the photovoltaic array output current detected in real time.
The determining step that environment in described step 7 there occurs slowly change is,
(1) judge whether the steady track of timer record exceeds schedule time cycle length, if overtime, reset timer and accumulative relative power variable quantity, otherwise continue timing;
(2) if at the appointed time, integral power relative variation E > 0.05, represent that environment there occurs slight change, namely there occurs slight skew between actual maximum power point and the maximum power point of memory, then reboot step 3 carries out Local Search.
Photovoltaic array multimodal value maximum power point tracing method based on the scanning of power closed loop disclosed by the invention, the location of global maximum power point is achieved rapidly under multi-peak situation, and achieve the accurate tracking of global maximum power point, its beneficial effect is embodied in:
1. not relying on the information of any known photovoltaic array, is run according to on-line checkingi information completely.
2. utilize the instability in power closed-loop control " valley point " region on photovoltaic array output power curve, automatically skip the region that there is not maximum power point, just can determine the position of maximum power point without the need to point by point scanning, dynamic process is fast, and power loss is little.
3. do not select the scope that overall MPP searches in advance, search procedure does not rely on starting point yet, so there is not the phenomenon that can not converge to global maximum power point.
4. near global maximum power point, have employed " 3 the collaborative variable step-size search methods " based on PSO algorithm, utilize the convergence property of the method, overcome the erroneous judgement problem that existing method dynamic process exists, avoid steady state power vibration, improve steady-state tracking precision.The result of actual test is, adopt tracking accuracy based on PSO algorithm up to 99.9%, and traditional " disturbance observation method " and the stable state accuracy of " conductance increment method " is all less than 98%.
5. in the dynamic case, the degree that can environmentally change restarts search procedure, achieves the quick response of environmental change.
6. especially it should be noted that, power closed-loop control in this method step 1 is local stability on photovoltaic array curve of output, when reference power is greater than the maximum power point of photovoltaic array curve of output existence, the output voltage of photovoltaic array will slide to the minimum operating voltage of photovoltaic DC-to-AC converter, thus achieve the scanning of photovoltaic array curve of output.Be different from prior art, other method existing is all each MPPT maximum power point tracking cycle just upgrade a peak power dot information, and the power closed-loop control of this method upgrades once in each sampling period.Even if other method also adopts each sampling period to upgrade peak power dot information, also do not have practical significance, its basic reason is just above-mentioned " power closed-loop control is local stability on photovoltaic array curve of output ".
Accompanying drawing explanation
Fig. 1 is overview flow chart of the present invention.
Fig. 2 realizes circuit theory diagrams of the present invention.
Fig. 3 is static multi-peak tracing process schematic diagram.
Restarting process schematic diagram when Fig. 4 is environmental catastrophe.
Fig. 5 is specific embodiment of the invention process flow diagram.
Fig. 6 is controlling of sampling program flow diagram.
Fig. 7 restarts 3 collaboratively searching process-initialize routine process flow diagrams.
Embodiment
Below in conjunction with accompanying drawing, clear, complete description is carried out to technical scheme of the present invention.Obviously described embodiment is only a part for the embodiment of the present invention, and based on embodiments of the invention, other embodiment that those skilled in the art obtains under the prerequisite not making creative work, all belongs to the protection domain of this patent.
The embodiment provides a kind of photovoltaic array multimodal value maximum power point tracing method based on the scanning of power closed loop, to solve, the tracing process that prior art exists is comparatively slow, energy loss is more, and follows the tracks of the problem of maximum power point failure.
Hardware circuit of the present invention should comprise the testing circuit of photovoltaic array output voltage, output current, DC bus-bar voltage.Photovoltaic combining inverter adopts two-stage type structure, and prime is DC-DC conversion circuit, for completing MPPT maximum power point tracking; Rear class is DC-AC inverter circuit, is realized the balance of photovoltaic array Implantation Energy and inversion output energy by the stability contorting of busbar voltage.System completes the initialization of MPPT maximum power point tracking circuit and program when powering on, complete the initialization of MPPT maximum power point tracking program variable.
Fig. 2 is for implementing a kind of circuit arrangement of the present invention.This circuit arrangement comprises photovoltaic array, photovoltaic array output voltage U
pvtesting circuit, photovoltaic array output current I
pvtesting circuit, and by inductance L, switch transistor T, diode D and dc-link capacitance C
dCthe BOOST circuit of composition, grid-connected inverter circuit, MPPT maximum power point tracking control circuit.Maximum power point tracing method disclosed by the invention is according to the U of on-line checkingi
pv, I
pvinformation, obtains the duty cycle signals of control BOOST circuit through MPPT maximum power point tracking computing, if the duty cycle signals of control BOOST circuit increases, then and I
pvincrease, U
pvreduce; If otherwise dutycycle reduces, then I
pvreduce, U
pvincrease.
For the static multi-peak situation shown in Fig. 3, when the hardware system that the present invention relies on powers on, BOOST circuit and grid-connected inverter circuit not yet work, and the working point of photovoltaic array is arranged in a point of Fig. 3, i.e. open-circuit voltage place.The now controlling of sampling cycle T of initialization system
s=50uS, MPPT maximum power point tracking cycle T
mppt=1 second.Each controlling of sampling cycle performs a controlling of sampling program, gathers output voltage and the output current of a photovoltaic array; Each MPPT maximum power point tracking cycle performs a MPPT maximum power point tracking program, changes a reference power or reference voltage.During programming, definition S
mpptas the mark in stage residing for MPPT maximum power point tracking.
For multi-peak P-V curve as shown in Figure 3, the basic step of multi-peak maximum power point tracing method disclosed by the invention is as follows:
See Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6 and Fig. 7,
Step 1, power closed-loop control scans:
Within each MPPT maximum power point tracking cycle, maximum power point tracing method is according to the given reference power value of mode of " current reference performance number=last reference power value+power step size ".Before the next MPPT maximum power point tracking cycle arrives, a controlling of sampling program can be called in each control cycle.
In sampling process, first by output voltage, the output current of on-line checkingi photovoltaic array, to obtain the real-time output power that photovoltaic array exports.The closed-loop control of recycling power makes real-time output power track reference power, thus obtains the control signal of MPPT maximum power point tracking circuit.
The process of power closed-loop control is, after obtaining real-time output power each time, by the comparison of real-time output power and known global maximum power, upgrades global maximum power point information, even P=U
pv* I
pv> P
m, then U
m=U
pv, P
m=P, the P in formula is real-time output power, U
pvfor the photovoltaic array output voltage, the I that detect in real time
pvfor the photovoltaic array output current, the U that detect in real time
mfor voltage, the P of known maximum power point
mfor the power of known maximum power point.The reference power of power closed-loop control is by formula P
r(k)=P
r(k-1)+P
stepdetermine, the P in formula
r(k) current reference power, P for following the tracks of
r(k-1) be the last reference power, the P that follow the tracks of
stepfor the step-length of reference power change.Due on photovoltaic array curve of output, power closed-loop control is local stability, when reference power is greater than the maximum power point of photovoltaic array curve of output existence, the output voltage of photovoltaic array will slide to the minimum operating voltage of photovoltaic DC-to-AC converter, achieve the scanning of photovoltaic array curve of output.
Does step 2, judge that photovoltaic array output voltage is less than the minimum operating voltage of photovoltaic DC-to-AC converter? proceed to step 3 when being less than, otherwise repeat step 1 and step 2.
By repeating step 1 and step 2, system works point on Fig. 3 successively through a → b → c → d → e → f → g → h (U
min), achieve the scanning of photovoltaic array output voltage range, and achieve the location of global maximum power point M.For e → f point, g → h (U in Fig. 3
min) region between point, power closed-loop control completes the scanning of e → f point within a MPPT maximum power point tracking cycle.After scanning process terminates, peak power dot information (U
m, P
m) information put for " 1 " near global maximum power point M point.
Step 3,3 collaborative variable step Local Searches:
First based on the photovoltaic array peak power output dot information (U obtained in step 1, step 2
m, P
m), set three initial work location; Three initial work location are according to U
1(k)=U
m, U
2(k)=U
m-U
step, U
3(k)=U
m+ U
stepdetermine, U wherein
1k voltage, U that () is first job point
2k () is voltage, the U of second working point
3k () is voltage, the U of the 3rd working point
mfor voltage, the U of known maximum power point
stepfor initial disturbance step-length.Within ensuing three peak power dot cycles, controlled by voltage close loop, photovoltaic array is worked to (variable C on three working points successively
wfor present operating point mark), utilize photovoltaic array output voltage, the output current of on-line checkingi simultaneously, obtain the output power of each working point.When MPPT maximum power point tracking end cycle, upgrade the peak power dot information of global maximum power point information and each working point experience.When three working points take turns to operate after one time, the information of three working points obtained is utilized jointly to determine the operating voltage of next round three working points; Wherein, the operating voltage of next round three working points is determined according to following formula:
Δ U in formula
1(k), Δ U
2(k), Δ U
3k () is the voltage disturbance amount in three working point current MPPT maximum power point tracking cycles, Δ U
1(k-1), Δ U
2(k-1), Δ U
3(k-1) be the voltage disturbance amount in three working point previous MPPT maximum power point tracking cycles, U
m1, U
m2, U
m3be the maximum power point voltage value that three working points experience separately, U
1(k-1), U
2(k-1), U
3(k-1) be the voltage in three working point previous MPPT maximum power point tracking cycles, ω ∈ (0,1), c
1∈ (0,1), c
2∈ (0,1) is quiescent potential step-length regulating parameter.
Does according to the magnitude of voltage of three working points, step 4, judge that whether three working points enough close? if following condition: P
m≠ 0, U
m-U
m1< U
step/ 10, U
m-U
m2< U
step/ 10, U
m-U
m3< U
step/ 10 meet simultaneously, P wherein
mfor power, the U of known maximum power point
mfor voltage, the U of known maximum power point
m1, U
m2, U
m3be respectively magnitude of voltage, the U at the maximum power point place that three working points experience separately
stepfor initial disturbance step-length, then for enough close to and proceed to step 5, otherwise repeat above-mentioned steps 3 and step 4.By repeating step 3 and step 4, the working point of system will converge to global maximum power point M, i.e. U
m=U
m, P
m=P
m, wherein U
m, P
mbe respectively voltage and the power of M point.
Step 5, determine voltage steady track:
Voltage close loop is first utilized to control, on the maximum power point that the output voltage stabilization of photovoltaic array is determined in step 3, step 4, i.e. U
pv=U
m=U
m.The photovoltaic array output voltage that recycling detects in real time and output current, calculate real-time output power.Afterwards, the peak power output obtained by more real-time output power and step 3, step 4, according to following formulae discovery relative power variable quantity and accumulative relative power variable quantity: E
p=1-U
pv* I
pv/ P
m, E=Σ E
p, the E in formula
pfor the accumulative relative power variable quantity that the relative power variable quantity in current MPPT maximum power point tracking cycle, E are multiple tracking cycle.When determining voltage steady track, peak power dot information no longer upgrades.
Does step 6, based on relative power variable quantity, judge that environment there occurs acute variation? if then first setting power reference value P
r(k)=(U
pv* I
pv)/2, simultaneously reset maximum power point power P
m=0, the U in formula
pvfor the photovoltaic array output voltage, the I that detect in real time
pvfor the photovoltaic array output current detected in real time.Reboot step 1 rescans again, under two kinds of situations as shown in Figure 4, and all can reboot step 1.
Does step 7, based on accumulative relative power variable quantity, judge that environment there occurs slow change? if so, then reboot step 3, otherwise proceed to step 5.When judging whether environment occurs slowly to change, first judge whether the steady track of timer record exceeds schedule time cycle length, if overtime, reset timer and accumulative relative power variable quantity, otherwise continue timing; If at the appointed time, integral power relative variation E > 0.05, represent that environment there occurs slight change, namely there occurs slight skew between actual maximum power point and the maximum power point of memory, then reboot step 3 carries out 3 collaborative variable step Local Searches.
Above-mentioned search procedure is a specific implementation process of the present invention, and the dependence diagram of MPPT maximum power point tracking process is as shown in Fig. 5, Fig. 6 and Fig. 7.
Claims (8)
1., based on a photovoltaic array multimodal value maximum power point tracing method for power closed loop scanning, comprise the output voltage of on-line checkingi photovoltaic array, output current, it is characterized in that completing steps is as follows:
Step 1, first by output voltage, the output current of on-line checkingi photovoltaic array, to obtain the real-time output power that photovoltaic array exports, the closed-loop control of recycling power makes real-time output power track reference power, thus obtains the control signal of MPPT maximum power point tracking circuit;
Step 2, judges whether photovoltaic array output voltage is less than the minimum operating voltage of photovoltaic DC-to-AC converter, proceeds to step 3 when being less than, otherwise repeats step 1 and step 2;
Step 3, first based on the photovoltaic array peak power output of acquisition in step 1 and step 2 and the output voltage values of correspondence thereof, set three initial work location, recycling voltage close loop controls, photovoltaic array is made to work on three working points successively, utilize the photovoltaic array output voltage of on-line checkingi simultaneously, output current, obtain the output power of each working point, when MPPT maximum power point tracking end cycle, upgrade the peak power dot information of global maximum power point information and each working point experience, when three working points take turns to operate after one time, the information of three working points obtained is utilized jointly to determine the operating voltage of next round three working points,
According to the magnitude of voltage of three working points, step 4, judges whether three working points meet following condition simultaneously: P
m≠ 0, U
m-U
m1< U
step/ 10, U
m-U
m2< U
step/ 10, U
m-U
m3< U
step/ 10, P wherein
mfor power, the U of known maximum power point
mfor voltage, the U of known maximum power point
m1, U
m2, U
m3be respectively magnitude of voltage, the U at the maximum power point place that three working points experience separately
stepfor initial disturbance step-length, if then proceed to step 5, otherwise repeat above-mentioned steps 3 and step 4;
Step 5, voltage close loop is first utilized to control, on the maximum power point that the output voltage stabilization of photovoltaic array is determined in step 3, step 4, the photovoltaic array output voltage that recycling detects in real time and output current, calculate real-time output power, afterwards, the peak power output obtained by more real-time output power and step 3, step 4, calculates relative power variable quantity and accumulative relative power variable quantity;
Step 6, based on relative power variable quantity, judges whether environment there occurs acute variation, if so, then reboot step 1;
Step 7, based on accumulative relative power variable quantity, judges whether environment there occurs slow change, if so, then reboot step 3, otherwise proceeds to step 5.
2. the photovoltaic array multimodal value maximum power point tracing method based on the scanning of power closed loop according to claim 1, it is characterized in that the process of the power closed-loop control in step 1 is, after obtaining real-time output power each time, by the comparison of real-time output power and known global maximum power, upgrade global maximum power point information, even P=U
pv* I
pv> P
m, then U
m=U
pv, P
m=P, the P in formula are real-time output power, U
pvfor the photovoltaic array output voltage, the I that detect in real time
pvfor the photovoltaic array output current, the U that detect in real time
mfor voltage, the P of known maximum power point
mfor the power of known maximum power point.
3. the photovoltaic array multimodal value maximum power point tracing method based on the scanning of power closed loop according to claim 1, is characterized in that reference power in step 1 is by formula P
r(k)=P
r(k-1)+P
stepdetermine, the P in formula
r(k) current reference power, P for following the tracks of
r(k-1) be the last reference power, the P that follow the tracks of
stepfor the step-length of reference power change.
4. the photovoltaic array multimodal value maximum power point tracing method based on the scanning of power closed loop according to claim 1, is characterized in that three initial work location in step 3 are according to U
1(k)=U
m, U
2(k)=U
m-U
step, U
3(k)=U
m+ U
stepdetermine, U wherein
1k voltage, U that () is first job point
2k () is voltage, the U of second working point
3k () is voltage, the U of the 3rd working point
mfor voltage, the U of known maximum power point
stepfor initial disturbance step-length.
5. the photovoltaic array multimodal value maximum power point tracing method based on the scanning of power closed loop according to claim 1, is characterized in that the operating voltage of next round three working points in step 3 is determined according to following formula:
Δ U in formula
1(k), Δ U
2(k), Δ U
3k () is the voltage disturbance amount in three working point current MPPT maximum power point tracking cycles, Δ U
1(k-1), Δ U
2(k-1), Δ U
3(k-1) be the voltage disturbance amount in three working point previous MPPT maximum power point tracking cycles, U
m1, U
m2, U
m3be the maximum power point voltage value that three working points experience separately, U
1(k-1), U
2(k-1), U
3(k-1) be the voltage in three working point previous MPPT maximum power point tracking cycles, ω ∈ (0,1), c
1∈ (0,1), c
2∈ (0,1) is quiescent potential step-length regulating parameter.
6. the photovoltaic array multimodal value maximum power point tracing method based on the scanning of power closed loop according to claim 2, is characterized in that relative power variable quantity in step 5 and accumulative relative power variable quantity are according to following formulae discovery: E
p=1-U
pv* I
pv/ P
m, E=Σ E
p, the E in formula
pfor the accumulative relative power variable quantity that the relative power variable quantity in current MPPT maximum power point tracking cycle, E are multiple tracking cycle.
7. the photovoltaic array multimodal value maximum power point tracing method based on the scanning of power closed loop according to claim 1, when it is characterized in that the reboot step 1 in step 6, value and power reference is according to P
r(k)=(U
pv* I
pv)/2 set, reset maximum power point power P simultaneously
m=0, the U in formula
pvfor the photovoltaic array output voltage, the I that detect in real time
pvfor the photovoltaic array output current detected in real time.
8. the photovoltaic array multimodal value maximum power point tracing method based on the scanning of power closed loop according to claim 1, the determining step that the environment that it is characterized in that in step 7 there occurs slowly change is,
(1) judge whether the steady track of timer record exceeds schedule time cycle length, if overtime, reset timer and accumulative relative power variable quantity, otherwise continue timing;
(2) if at the appointed time, integral power relative variation E > 0.05, represent that environment there occurs slight change, namely there occurs slight skew between actual maximum power point and the maximum power point of memory, then reboot step 3 carries out Local Search.
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| CN105159388B (en) * | 2015-09-02 | 2016-10-05 | 广东明阳龙源电力电子有限公司 | A kind of method of the MPPT maximum power point tracking in photovoltaic microgrid system |
| CN106527570B (en) * | 2016-12-20 | 2018-06-15 | 湘潭大学 | A kind of photovoltaic array multimodal maximum power group hunting optimizes tracking |
| CN107168450A (en) * | 2017-06-14 | 2017-09-15 | 刘博文 | A kind of solar energy power generating MPPT maximum power point tracking control system and method |
| CN109753102B (en) * | 2017-11-01 | 2021-08-03 | 天津科技大学 | Improved photovoltaic fuzzy MPPT control method |
| CN107992154B (en) * | 2017-12-18 | 2020-02-04 | 深圳市英威腾光伏科技有限公司 | Maximum power tracking method and device |
| CN108037792A (en) * | 2017-12-31 | 2018-05-15 | 华南师范大学 | A kind of multi-peak MPPT algorithm |
| CN108983864B (en) * | 2018-10-15 | 2020-06-30 | 西安许继电力电子技术有限公司 | Tracking method and tracking device for photovoltaic maximum power point |
| CN111538366B (en) * | 2020-04-03 | 2021-12-21 | 福建星云电子股份有限公司 | Maximum power point tracking method, system, device and medium |
| TWI750714B (en) * | 2020-06-24 | 2021-12-21 | 亞源科技股份有限公司 | Method and system for dynamic maximum power point tracking |
| CN111969945B (en) * | 2020-08-17 | 2021-08-20 | 博阳能源科技有限公司 | quasi-MPPT novel photovoltaic panel tracking method, equipment and storage medium |
| CN112162589B (en) * | 2020-08-31 | 2021-10-12 | 中国科学院上海微系统与信息技术研究所 | Maximum power point tracking control method based on conductance incremental method and particle swarm optimization |
| CN113178894B (en) * | 2021-06-09 | 2024-04-12 | 阳光电源股份有限公司 | Photovoltaic inverter and MPP scanning control method thereof |
| CN113485516B (en) | 2021-06-30 | 2022-11-08 | 华为数字能源技术有限公司 | Photovoltaic system and maximum power point tracking control method thereof |
| CN114911301A (en) * | 2022-04-27 | 2022-08-16 | 深圳市正浩创新科技股份有限公司 | Maximum power tracking control method, photovoltaic system and energy storage equipment |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000074200A1 (en) * | 1999-05-27 | 2000-12-07 | Alan Henry Weinberg | Battery charging and discharging system |
| CN101119031A (en) * | 2007-06-08 | 2008-02-06 | 清华大学 | Photovoltaic three-phase grid control method for fast and steadily implementing maximal power tracing |
| US20080037305A1 (en) * | 2003-02-21 | 2008-02-14 | Distributed Power, Inc. | Monopolar dc to bipolar dc to ac converter |
| US20090316452A1 (en) * | 2008-06-24 | 2009-12-24 | Samsung Electro-Mechanics Co., Ltd. | Power supply having maximum power point tracking function |
| CN102436285A (en) * | 2011-11-16 | 2012-05-02 | 深圳航天科技创新研究院 | Method and device for tracking maximum power point of photovoltaic array |
| CN102566645A (en) * | 2010-12-15 | 2012-07-11 | 上海电科电器科技有限公司 | Maximum power control method of photovoltaic grid-connected inverter |
-
2014
- 2014-05-05 CN CN201410186475.4A patent/CN103955253B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000074200A1 (en) * | 1999-05-27 | 2000-12-07 | Alan Henry Weinberg | Battery charging and discharging system |
| US20080037305A1 (en) * | 2003-02-21 | 2008-02-14 | Distributed Power, Inc. | Monopolar dc to bipolar dc to ac converter |
| CN101119031A (en) * | 2007-06-08 | 2008-02-06 | 清华大学 | Photovoltaic three-phase grid control method for fast and steadily implementing maximal power tracing |
| US20090316452A1 (en) * | 2008-06-24 | 2009-12-24 | Samsung Electro-Mechanics Co., Ltd. | Power supply having maximum power point tracking function |
| CN102566645A (en) * | 2010-12-15 | 2012-07-11 | 上海电科电器科技有限公司 | Maximum power control method of photovoltaic grid-connected inverter |
| CN102436285A (en) * | 2011-11-16 | 2012-05-02 | 深圳航天科技创新研究院 | Method and device for tracking maximum power point of photovoltaic array |
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