Smart Solar Tracker is designed to maintain angle in a horizontal and vertical position of mounted on it device/collector. In our case the Smart Tracker was used for appropriate alignment of tilt, pan, roll angles of photovoltaic panels corresponding to geographical location in relation to the changing position of the sun, in a way, so that sun rays fall on modules fixed on the panel, at an optimal angle to reach the possibly longest time period of maximal power production over every day in the year.
This solution greatly improves efficiency of photovoltaic modules. Measurements taken at an altitude of 51 °N, indicate that energetic efficiency of photovoltaic panels fixed on our rack, over the whole year, increased by 40% in comparison to modules with the same power, fixed on a roof surface in a standard way with direction of 0 °S and tilted at a 35° angle.
Such increment of efficiency allows to greatly limit cost of investments and save space that is necessary to achieve assumed efficiency of the whole installation. Introducing an inexpensive and easy in maintenance and repair design is a condition to achieve this goal.
In the current market there are solutions which allow to modify the position of photovoltaic panels in one or two planes. However, available constructions are designed to handle too small number of panels on a single rack, to make the purchase of such system to be economically reasonable. The reason of limiting the size of the panel surface is inability to expose as-is design to unfavorable atmospheric conditions, e.g. wind force. Suggested rack designs, e.g. of a column type, absorb essential amount of produced energy to position the panels, especially when we deal with the influence of air masses.
So far, producers use centrally positioned column, in order to apply central mounting of a bearing what results in a lack of possibility to use a drive mechanism other than the one based on a toothed rim. Column based solutions cause an increase of rack production and raise the cost of the whole system.
Some devices that may be found in the market, allow for installation of the larger number of modules, however, they are costly in production because of an expensive method of bearing mounting and an expensive drive for the column structure. Large non-modular elements, force the need for special type of transport and specialised tools and competences for installation. That results in inadequate design-related costs. Such approach of create an extensive farms which have relatively poor return rate of the investment.
Central column alternative
Because economically optimal diameter of the system should be equal to a minimum of 1.5m in radius, the Smart Tracker guide has to have a modular structure, which allows to achieve this assumption without logistic constraints which appear in solid elements. Relatively large diameter of the guide in relation to the height of the rack allowed to acquire three very important and unavailable for other designs, features:
Increased stiffness of the design and frame based structure also enabled to eliminate a weak point of the construction which resulted from imperfections of market available drives designed to tilt the working plane. Engineers commonly use linear motors based on a trapezoidal screw. With mounting as shown on the exemplary figure;
Because the mounting of the linear actuator on a pole structure has to be done in a way that enables the movement of the mounting together with the upper frame, the size of the actuator and its parameters must be significantly limited. The weakness of this solution manifests with a low resistance to a jerk of waving plane working on the wind. The wavy motions are a result of combination of dynamic force of the wind and gravity. The size of the working plane increases the torque that is transferred by the constructions to the linear actuator.
Usage of the dedicated slide drive enables to acquire a beneficial stiffness of the structure, and in addition, in the moment of adjusting working plane to the horizontal secure position (similar to the parallel position towards the earth), it greatly increases the resistance of the system on influence of strong and gusty winds. Most of the controllers available in the market, after connecting a wind gauge, enable to set the rack in a default and safe position in case of detection of threshold speed of the wind. Default position in actual working conditions is not always optimal because of the terrain shape.
Our dedicated slide drive also plays a reinforcing role for the main frame, because its guide is integrated with the elements of the whole framing by skeletal structure.
Time to disrupt the artificial division of drivers for those operating in closed and open systems. This division results from assigning certain precursors of particular solutions to the technology, what further causes stagnation in driver development. In the current market there are only a few of products which bring satisfactory results in tests. All of the remaining solutions focus mainly on theoretical issues and not on constructive aspect for the market needs.
By using developed nomenclature, closed systems will work fine in tropical regions with insignificant occurrence of cloudiness – only in places where rainy seasons or any other climatic changes in the environment between seasons are minimal. Open loop systems, in the form of pure algorithm, will be able to solve problems of unstable irradiation, however, their usefulness is rather laboratorial.
The REI vision assumes a conception of a driver which exceeds the current level of technology, a driver which successfully realizes a concept of hybrid system and at the same time is fully configurable and manageable. A driver which leaves the choice for a user. We abolish restrictions produced by a conventional division resulting from inflexibly coded operational logic.
REI Driver opens unlimited possibilities, thanks to the usage of efficient IoT platforms, which allow to relatively easily, change implementation of primary and secondary algorithms, therefore to control the behavior of the whole system.
By supplementing algorithm calculations with transformations of data ongoing from sensors and unlimited number of peripherals, it is possible to run auto-calibration of the system even in the most harsh field conditions.
We open the way to facilitate collection of data for further research. We enable a mutual correction of operation of cooperating racks in a master-slave configuration. Therefore, we create an opportunity to use machine learning or artificial intelligence for more sophisticated applications