Patent Publication Number: US-2013240005-A1

Title: Cleaning system for solar panel

Description:
BACKGROUND 
     1. Technical Field 
     The present disclosure relates to a system for cleaning a solar panel. 
     2. Description of Related Art 
     Solar energy is an excellent alternative source of energy, and has found widespread applications in a variety of fields. However, when a solar panel has been used for a period of time, the solar panel may be become dirty, such that the efficiency of the solar panel would be reduced. However, the cleaning of the solar panels are mostly done manually. This is inconvenient. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
       Many aspects of the embodiments can be better understood with reference to the following drawing. The components in the drawing are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present embodiments. Moreover, in the drawing, like reference numerals designate corresponding parts throughout the several views. 
       The FIGURE is a block diagram of an exemplary embodiment of a cleaning system for solar panels. 
     
    
    
     DETAILED DESCRIPTION 
     The disclosure, including the accompanying drawing, is illustrated by way of examples and not by way of limitation. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean at least one. 
     Referring to the FIGURE, an exemplary embodiment of a cleaning system for solar panels is shown. The solar panels include a first solar panel  10  and N second solar panels  11 - 1 N. The first solar panel  10  is a reference solar panel. The second solar panels  11 - 1 N are solar panels to be cleaned. The first solar panel  10  and the N second solar panels  11 - 1 N collect solar energy and convert the solar energy to electrical energy. In the embodiment, N is an integer not less than one. 
     The cleaning system includes a first power measuring unit  20 , N second power measuring units  21 - 2 N, a first storing unit  30 , N second storing units  31 - 3 N, a processing unit  40 , a first control unit  50 , N second control units  51 - 5 N, a first cleaning unit  60 , and N second cleaning units  61 - 6 N. 
     In the embodiment, the first control unit  50  controls the first cleaning unit  60  to clean the first solar panel  10  per interval of time (such as twelve hours). As a result, the first solar panel  10  is almost clean all the time. The first power measuring unit  20  measures a power P 0  outputted from the first solar panel  10  per unit interval. The first storing unit  30  stores the power P 0  measured by the first power measuring unit  20 . 
     The second power measuring units  21 - 2 N measure powers P 1   n  outputted from the second solar panels  11 - 1 N correspondingly per interval of time, where n is a natural number which is less than (N+1). For example, the second power measuring unit  21  measures a power P 11  outputted from the second solar panel  11  per interval of time, and the second power measuring unit  26  measures a power P 16  output from the second solar panel  16  per interval of time. The second storing units  31 - 3 N store the power P 1   n  measured by the second power measuring unit  21 - 2 N correspondingly. Each second storing unit further stores a proportional coefficient Kn between the power outputted from each second solar panel when the second solar panel is clean and the power outputted from the first solar panel  10  per interval of time. In other words, Kn=P 2   n /P 0 , where P 2   n  stands for the power outputted from a second solar panel per interval of time when the second solar panel is clean. For example, P 21  stands for the power outputted from the second solar panel  11  when the second solar panel  11  is clean. Moreover, each second storing unit further stores a preset coefficient M (such as 90%). When the power outputted from a second solar panel is less than M times of the power P 2   n,  the second solar panel needs to be cleaned. 
     The processing unit  40  reads the power P 0  measured by the first power measuring unit  20  per interval of time, the power P 1   n  measured by the second power measuring units  21 - 2 N per interval of time, the proportional coefficient Kn, and the preset coefficient M. The processing unit  40  further compares the power P 1   n  with a product of the power P 0 , the proportional coefficient Kn, and the preset coefficient M. In other words, the processing unit  40  determines whether the following formula is satisfied: P 1   n &lt;P 0 ×Kn×M. If P 1   n &lt;P 0 ×Kn×M, the corresponding second solar panel is to be cleaned. The processing unit  40  outputs a control signal to the corresponding second control unit. The second control unit controls the corresponding second cleaning unit to clean the second solar panel. For example, when P 15 &lt;P 0 ×K 5 ×M, the second solar panel  15  is need to be cleaned. The processing unit  40  outputs a control signal to the second control unit  55 . The second control unit  55  controls the second cleaning unit  65  to clean the second solar panel  15 . 
     In the embodiment, the preset coefficient M is depended on weather. For example, when it is a sunny day, the preset coefficient M can be set as 90%. When it is a cloudy day, the preset coefficient M can be set as 80%. Operators can set the preset coefficient M according to need. 
     The foregoing description of the exemplary embodiments of the disclosure has been presented only for the purposes of illustration and description and is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Many modifications and variations are possible in the light of everything above. The embodiments were chosen and described in order to explain the principles of the disclosure and their practical application so as to enable others of ordinary skill in the art to utilize the disclosure and various embodiments with various modifications as are suited to the particular use contemplated. Alternative embodiments will become apparent to those of ordinary skills in the art to which the present disclosure pertains without departing from its spirit and scope. Accordingly, the scope of the present disclosure is defined by the appended claims rather than the foregoing description and the exemplary embodiments described therein.