A kind of photovoltaic tracking automatic control system
Technical field
The present invention relates to a kind of point source tracking control system.
Background technology
Photovoltaic generation cost height, the low subject matter being to restrict for a long time its high speed development of efficiency at present, one of its solution route is
Realize the photovoltaic module round-the-clock tracking to the sun, make photovoltaic module remain at the absorption maximum position to solar radiation energy
Put, thus improve the generated energy of electricity generation system, reduce photovoltaic generation cost, the purpose of raising photovoltaic efficiency.Through surveying
Calculating, double-shaft solar tracking system exports than the power of fixed system can increase by more than 40%.
There is many drawbacks in present tracking system, is unfavorable for popularization and the application of its system.Current tracking system is broadly divided into
Two classes, sensor is followed the tracks of and regards daily motion track following.Obtained by local calculation of longitude & latitude depending on daily motion track following mode
Every day the sun position, thus realize round-the-clock tracking, but its precision be the highest, and solar-electricity cannot be verified during following the tracks of
Pond plate is the most just to the sun.Once installing, just inconvenience is moved or mounting or dismounting, has moved every time and has been necessary for resetting data and adjustment
Parameters, principle, circuit, technology, equipment are the most complicated, and layman can not at will operate.Sensor detection side
Formula follows the trail of position of sun by four-quadrant light sensor detection light intensity signal, and advantage is simple in construction, and cost is relatively low, shortcoming
The scope being the accuracy of the structure influence testing result of detection part and detection angles is little, when solar panel normal direction with
Cannot realize when solar direction drift angle is excessive following the tracks of, and easily be scattered by other, reflect, reflect light during sensor tracking
Interference.
Sensor tracking mode typically uses four-quadrant photo detector, and its operation principle is: general by four-quadrant photo detector
Be placed in optical system focal plane or slightly off focal plane, as illustrated in figure 1 c, target light signal after optical system at four-quadrant light
Imaging on electric explorer, when target imaging is not on optical axis, on 4 quadrants, the photosignal amplitude of detector output differs,
Relatively the amplitude size of 4 photosignals is it is known that target imaging is on which quadrant, has also been known that the orientation of target.Four
Quadrant photodetector is the change in location by measuring the spot center from light source, and determines light by certain algorithm simultaneously
The side-play amount of the both direction of speckle, is converted into side-play amount motor drive signal and drives electric machine rotation, when spot center and four-quadrant
When photodetector center is consistent, the resistive of 4 quadrant negative electrode generations is the most equal, is output as zero through operational amplifier, two
The straightness error in direction is also zero, motor stalls.
The advantage of this detection mode is simple in construction, and cost is relatively low, shortcoming be lens barrel height affect testing result accuracy and
The range size of detection angles, when solar panel normal direction and solar direction drift angle are excessive, hot spot arises that four
On lens barrel wall outside quadrant, so that sensor cannot detect the position of the sun, so cannot realize following the tracks of.And by sky
Gas impact is big, overcast and rainy, cannot be directed at the sun, even cause the misoperation of actuator, thus cause provided tracking to be believed
Number instability, selects the sensor that precision is high, can increase again tracking cost.
Patent 201010204455.7 is a kind of universal-type solar real-time automatic tracking control system based on microcomputer, and this is special
Profit is pure sensor tracking mode, and the sensor used is light-sensitive cell, and concrete structure is as shown in Figure 2.Cardinal principle is light
Quick battery 14 and 17,12 and 15 separately constitutes a pair, when there are differences between paired light-sensitive cell, illustrates that position of sun has change
Dynamic, drive the horizontal rotation motor of tracking support and vertical tracking motor to be tracked respectively according to difference.
The problem that this tracking mode exists two aspects:
One, pure sensor tracking mode and sensor expose, and block without any, easily by surrounding objects reflection, refraction sunlight and
The impact of other light sources, the especially sunlight of solar panel reflection, when these intensity signals are irradiated on cell panel,
Easily cause the misoperation of tracking.Tracking system is caused frequently to rotate and on the drift.
Two, this tracking mode tracking angle is less, and maximum trail angle is 90 degree, causes when the sun and cell panel normal direction angle
Cannot realize when degree is more than this scope following the tracks of, there is large-scale dead angle.Such as: when morning, the sun rose, cell panel was due to yesterday
It tracking result is the most just in the face of west, and cell panel cannot realize following the tracks of back to the sun;When occurring that the time at cloudy day is longer (such as
Start fine day after cloudy day, at 2 at noon in the morning 8) time, owing to without the sun, tracking direction keeps constant, works as the sun
During appearance, having exceeded the following range of sensor owing to following the tracks of angle, cell panel cannot realize following the tracks of.
Summary of the invention
The invention aims to overcome the disadvantages mentioned above of existing tracking system, it is proposed that a kind of for solar tracking system
New control system.The present invention not only can improve accuracy of detection, and the detection range of light source position can be extended to maximum
The limit, no matter the sun and cell panel are in any position, and cell panel can the position of the proper alignment sun realize following the tracks of.
Photovoltaic tracking automatic control system of the present invention specifically include that GPS module, sensor assembly, signal filtering module, 485 lead to
News module, CPU module, liquid crystal display screen, tracking output modular converter and tracking support.GPS module and CPU module are by communication side
Formula connects, and on-site longitude and latitude and temporal information are passed to CPU module by GPS module;It is arranged on tracking cradle top surface margin location
The sensor assembly put is directly connected to signal filtering module, and the sun light intensity signal collected is passed to signal filtering module,
After signal filtering module is to light intensity signal Filtering Processing, pass to the CPU module directly connected;485 communication modules are by logical
News mode is connected with CPU module, it is achieved far-end computer and the both-way communication of CPU module;Follow the tracks of output modular converter directly and CPU
Module connects, and the logical signal that CPU module exports is converted to follow the tracks of the rotation driver signal of motor on support, drives motor rotation
Turn, change the direction of cell panel;Following the tracks of support is the critical piece supporting solar panel, it is provided with the angle of pitch and rotates
Motor and horizontal rotation motor, can realize rotating with pitch orientation in the horizontal direction.
GPS module by the longitude and latitude received by antenna, date and time information with serial communication by the way of pass to CPU module,
Date and time, after calculating, is shown on liquid crystal display screen by CPU module.Sensor assembly by five identical photoconductive resistance and
The positive tetrahedron composition of fixing photoconductive resistance, described positive tetrahedron five face center except the base have groove, five light
Quick resistance is separately fixed in the groove on five surfaces of positive tetrahedron.Photoconductive resistance is used for obtaining sun light intensity signal, positive tetrahedron
For blocking the scattering of other directions, the interference illumination of reflection and weakening the solar irradiation value in non-oriented direction, to improve precision.Pass
The sun light intensity signal detected is input to CPU module after signal filtering resume module by sensor module, and CPU module will receive
To signal after AD conversion, be calculated current position of sun by vector method, and by current position of sun signal and storage
The same day, sun normal place compared, and after contrast computing, CPU module output control signal, through following the tracks of output modular converter
Directly drive the motor following the tracks of support to rotate after conversion, make the solar panel front on tracking support just to the sun.Liquid crystal display screen
By CPU module control to keep to show in real time current position of sun and solar panel towards.CPU module can store history thing
Part, the same day sun normal place, the running orbit record of solar panel in three months.485 communication modules are to maintain CPU
Module and the Primary Component of far-end upper machine communication, can complete remote control information to be transferred to CPU module and by the letter of this system
The function that breath is uploaded, makes power station staff understand the inclement weather conditions such as the direction of solar panel, especially strong wind at any time
Under, tracking support can be set level by power station staff by remotely control, it is to avoid brings unnecessary loss.
Sensor assembly is arranged on tracking cradle top surface marginal position, no matter solar direction and cell panel normal direction by fixing seat
Angle how, can ensure that light sensor at least one side is able to detect that position of sun.The bottom surface of sensor positive tetrahedron
For stationary plane, it is fixed on shaggy plank, prevents the sunlight interference sensor that the fixing seat of sensor assembly reflects.
Described plank is parallel with being fixed on the solar panel followed the tracks of on support.The angle of pitch limit angle of solar panel is
180 degree, this kind of situation usually morning or the sun in evening are in position, horizon, and solar panel is vertically placed back to the sun.
Now sensor assembly at least can directly detect illumination near the one side at cell panel edge, thus is calculated by CPU module
Obtain the position of the sun;Vertical direction limit angle is 270 degree, and this kind of situation usually morning or the sun in evening are in horizon
Position, the vertical setting side of solar panel is to the sun.Now at least one side is just to the sun, by CPU module meter for sensor
Calculate the position obtaining the sun.
The same day, the normal place definition procedure of the sun was as described below, when tracking control system of the present invention starts first, and CPU module root
The longitude and latitude data obtained according to GPS module, calculate whole day sun place all the time by the sun around the rule that the earth runs
Elevation angle and deflection, obtain the sun normal place of current whole day and store.Then photosensitive according to sensor assembly five positions
The light intensity signal of electrical resistance collection is calculated current time to CPU module, CPU module by vector method through signal filtering module transfer
Under position of sun, the sun normal place that the position of sun under current time stores with CPU module is compared, through contrast fortune
After calculation, CPU module output control signal, be converted to follow the tracks of the rotation driver signal of motor on support through following the tracks of output modular converter,
Driving and follow the tracks of support rotation, postpone when tracking support rotation arrives specific bit, sensor assembly detects the light intensity signal of the sun again,
By signal filtering module transfer to CPU module, vector method is utilized to be calculated the three-dimensional coordinate of current position of sun, sun position
The angle putting coordinate and Z axis is the normal direction of current solar panel and the angle deviation of solar direction, if angle deviation
In precision allowed band, i.e. can determine whether now to follow the tracks of the solar panel on support just to the sun.If solar panel is just
To the sun, CPU module sends normal direction and the solar direction of solar panel on signal update liquid crystal display screen and far-end host computer
Angle deviation, and revise CPU module storage sun normal place, using revised position of sun as second day follow the tracks of use
Sun normal place.
The computational methods of vector method are as described below, and the light intensity signal of sensor assembly five positions photoconductive resistance detection is through CPU mould
After block processes, it is converted into five three-dimensional vector coordinates with size and Orientation, after vector merges, finally gives vector direction
The position of the sun being under current time.
Automatic control system degree of accuracy of the present invention is higher, drastically increases the utilization rate of solar energy;Follow the tracks of support and rotate conveniently,
It is beneficial to safeguard and emergency process;The historical data of CPU module storage is to run rail with post analysis locality light conditions, the sun
The situations such as mark, equipment operation provide strong data support.
Accompanying drawing explanation
Fig. 1 prior art four-quadrant photo detector schematic diagram;
The sensor construction schematic diagram of Fig. 2 patent 201010204455.7;
Fig. 3 is the operation principle block diagram of the present invention;
Fig. 4 is sensor of the invention three-dimensional corresponding relation figure.
Detailed description of the invention
The present invention is further illustrated below in conjunction with the drawings and specific embodiments.
Photovoltaic tracking automatic control system of the present invention includes: GPS module 2, sensor assembly 1, signal filtering module 3,485 are led to
News module 4, CPU module 6, liquid crystal display screen 7, tracking output modular converter 8 and tracking support 5.GPS module 2 is passed through with CPU module 6
Communication modes connects, and on-site longitude and latitude and temporal information are passed to CPU module 6 by GPS module 2;Sensor assembly 1 and letter
Number filtration module 3 is directly connected to, and the light intensity signal collected passes to signal filtering module 3, and signal filtering module 3 is to light intensity
Signal filtering passes to the CPU module 6 directly connected after processing;485 communication modules 4 are by communication modes with CPU module 6 even
Connect, it is achieved far-end computer and the both-way communication of CPU module 6;Follow the tracks of output modular converter 8 to be directly connected with CPU module 6, by CPU
Signal that the logical signal of module 6 output is converted to drive motor to rotate also exports, and drives tracking support 5 to rotate;Follow the tracks of support
5 is the critical piece supporting solar panel, and it is provided with angle of pitch electric rotating machine and horizontal rotation motor, can be in level
Direction and pitch orientation realize rotating.
Sensor assembly is arranged on tracking support 5 top edge position, and no matter the angle of solar direction and cell panel normal direction is such as
What, can ensure that light sensor at least one side is able to detect that position of sun.The bottom surface of sensor positive tetrahedron is stationary plane,
Being fixed on shaggy plank, the sunlight preventing the fixing seat of sensor assembly from reflecting disturbs the detection of sensor, plank
Parallel with solar panel.
Fig. 3 is the operation principle block diagram of the present invention.GPS module 2 is by the longitude and latitude received by antenna, date and time information
Passing to CPU module 6 in the way of serial communication, date and time information is shown at liquid after Data Format Transform by CPU module 6
On brilliant screen 7.As shown in Figure 4, sensor assembly 1 is by five photoconductive resistance 10,11,12,13,14 and fixing photoconductive resistance
Positive tetrahedron 9 forms, and described positive tetrahedron five face center except the base have groove, five photoconductive resistance 10,11,
12,13,14 it is separately fixed in the groove on five surfaces of positive tetrahedron 9.Photoconductive resistance is used for obtaining sun light intensity signal,
Positive tetrahedron is for blocking the scattering of other directions, the interference illumination of reflection and weakening the solar irradiation value in non-oriented direction, to improve
Precision.The sun light intensity signal detected is input to CPU module 6, CPU after signal filtering module 3 processes by sensor assembly 1
The signal that receives after AD conversion, is calculated current position of sun by vector method by module 6, and by current sun position
Confidence number compares with the sun normal place on the same day stored, and after contrast computing, CPU module 6 exports control signal, through following the tracks of
Output modular converter 8 is converted to follow the tracks of the rotation driver signal of motor on support 5, drives tracking support 5 to rotate, makes tracking support 5
On solar panel front just to the sun.Liquid crystal display screen 7 by CPU module 6 control to keep to show in real time current position of sun and
Solar panel towards.CPU module 6 is for storing historical events, the normal place of the sun on the same day, and in three months too
The running orbit record of sun energy cell panel.485 communication modules 4 are to maintain CPU module 6 and the Primary Component of far-end upper machine communication,
Can complete remote control information is transferred to CPU module 6 and CPU module 6 stores the function that information is uploaded, especially strong wind etc. are disliked
Under bad weather condition, tracking support 5 can be set level by power station staff by remotely control, it is to avoid brings unnecessary loss.
The specific works order that the present invention follows the tracks of process is as follows: when present system starts, CPU module 6 is according to five positions light
The output voltage signal of quick resistance is calculated the particular location of the sun under current time by vector method, and stores too with system
Sun normal place compares, and after contrast computing, CPU module 6 exports control signal, is converted to through following the tracks of output modular converter 8
Drive and follow the tracks of the signal of motor rotation on support 5 and drive tracking support 5 to rotate, postpone when tracking support 5 arrives specific bit, pass
Sensor module 1 detects the light intensity signal of the sun again, is transferred to CPU module 6 by signal filtering module 3, utilizes vector method to calculate
The angle obtaining the three-dimensional coordinate of current position of sun, position of sun coordinate and Z axis is the normal side of current solar panel
To the angle deviation with solar direction, if angle deviation is in allowed band, i.e. can determine whether now to follow the tracks of the solar energy on support 5
Cell panel is just to the sun.If solar panel is just to the sun, CPU module 6 sends the video data of signal update liquid crystal display screen 7,
And the angle deviation of the normal direction of current solar panel and solar direction on far-end host computer, and revise CPU module 6 and deposit
The sun normal place of storage, the sun normal place followed the tracks of as second day using revised position of sun.
The computational methods of vector method are as described below, and the photoconductive resistance output voltage signal of five positions is after CPU module 6 processes
It is converted into five three-dimensional vector coordinates with size and Orientation, after vector merges, finally gives vector direction be the most too
Sun locality, after current position of sun direction determines, i.e. can get current position of sun.