Abstract:
Disclosed is an apparatus for measuring temperature coefficients of a concentrator photovoltaic module. The apparatus includes a solar simulator for providing a radiant source, a environment chamber, a concentrator photovoltaic module, a temperature control unit for controlling the temperature of environment chamber, a circuit-voltage curve measurement unit for measuring current-voltage characteristics of a photovoltaic device and a reference cell for measuring the irradiation of the solar simulator.

Description:
CROSS REFERENCE TO RELATED PATENT APPLICATIONS 
       [0001]    This application claims priority from Taiwan Patent Application No. 098136795, filed in the Taiwan Patent Office on Oct. 30, 2009, entitled “Apparatus for Measuring the Temperature Coefficients of a Concentrator Photovoltaic Module,” and incorporates the Taiwan patent application in its entirety by reference. 
       TECHNICAL FIELD 
       [0002]    The present disclosure relates to an indoor measurement apparatus for measuring the temperature coefficients of a concentrator photovoltaic module. 
       DESCRIPTION OF THE RELATED ART 
       [0003]    Photovoltaic modules for converting the solar energy into electricity gets more attention as the fossil fuels are gets more expensive. The prices of the photovoltaic modules are determined by photo-electric conversion efficiencies and photovoltaic characteristics. The photovoltaic characteristics of a concentrator photovoltaic module are determined by its temperature coefficients. The temperature coefficients are the most important performance parameters of the power output related to the temperature. The photovoltaic characteristics of a concentrator photovoltaic module can be calculated from the temperature coefficients. 
         [0004]    There has not been any indoor measurement apparatus specifically devised to measure the temperature coefficients of a concentrator photovoltaic module. Typically, for outdoor tests, the apparatus including a solar tracker, a current-voltage curve measuring unit and a temperature measuring unit is used to measure the temperature coefficients of a concentrator photovoltaic module. 
         [0005]    The above-mentioned apparatus is limited by outdoor climatic conditions although it can measure the temperature coefficients of a concentrator photovoltaic module. Moreover, it is difficult to control the temperature of a concentrator photovoltaic module. It is more difficult to control the uniform temperature distribution of a concentrator photovoltaic module. Therefore, the precision of the measurement is bad. 
         [0006]    The present disclosure is therefore intended to obviate or at least alleviate the problems encountered in prior art. 
       SUMMARY OF THE DISCLOSURE 
       [0007]    It is the primary objective of the present disclosure to provide an apparatus for precisely measuring the temperature coefficients of a concentrator photovoltaic module. 
         [0008]    To achieve the foregoing objective of the present disclosure, the apparatus includes a solar simulator, an environment chamber, a temperature controller, a reference cell and a measuring unit. The solar simulator emits collimated light in imitation of the sun light. The environment chamber includes a case, a gate, at least one door and a holder. The case includes front and rear openings. The gate is operable to close the front opening of the case before the temperature of the interior of the case reaches a desired value. The gate is operable to open the front opening of the case to allow the collimated light to reach the concentrator photovoltaic module after the temperature of the interior of the case reaches the desired value. The door is operable to open the rear opening through which the concentrator photovoltaic module is located in the case and closing the rear opening of the case before the temperature of the interior of the case reaches the desired value. The holder is located in the case and operable to hold the concentrator photovoltaic module. The temperature controller is connected to the case. The reference cell is located in the case. The measuring unit includes a first cable electrically connected to the concentrator photovoltaic module and a second cable electrically connected to the reference cell. 
         [0009]    Other objectives, advantages and features of the present disclosure will become apparent from the following description referring to the attached drawings. 
     
    
     
       BRIEF DESCRIPTIONS OF THE DRAWINGS 
         [0010]    The present disclosure will be described via detailed illustration of the preferred embodiment referring to the drawings wherein: 
           [0011]      FIG. 1  is a cross-sectional view of an apparatus for measuring the temperature coefficients of a concentrator photovoltaic module according to the preferred embodiment of the present disclosure; 
           [0012]      FIG. 2  is a perspective view of an environment chamber of the apparatus shown in  FIG. 1 ; 
           [0013]      FIG. 3  is an enlarged front view of the environment chamber shown in  FIG. 2 ; 
           [0014]      FIG. 4  is a perspective view of the environment chamber shown in  FIG. 3 ; and 
           [0015]      FIG. 5  is another cross-sectional view of the apparatus shown in  FIG. 1  in operation. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0016]    Referring to  FIGS. 1 and 5 , there is shown an apparatus for measuring the temperature coefficients of a concentrator photovoltaic module  5  according to the present disclosure. The apparatus includes a solar simulator  1 , an environment controller  2 , a temperature controller  3 , a measuring unit  4 , a power supply  6  and a reference cell  7 . 
         [0017]    The solar simulator  1  includes a light  11 . The light  11  emits collimated light in imitation of the sun light. 
         [0018]    Further referring to  FIGS. 2 through 4 , the environment chamber  2  includes a case  21  supported on a stand  23 . The case  21  includes a front opening  219 , a rear opening  214 , a front chamber  211 , a rear chamber  212  and a opening  213 . The opening  213  is located between the front chamber  211  and the rear chamber  212 . The area of the opening  213  is smaller than that of the front and rear openings  219 ,  214 . The front chamber  211  and the rear chamber  212  are located between the front opening  219  and the rear opening  214 . An inlet  216  is defined in a roof of the case  21 . An outlet  217  is defined in a floor of the case  21 . 
         [0019]    A gate  22  is movably provided on the case  21 . The gate  22  closes and opens the front opening of the case  21 . Two doors  218  are pivotally connected to the case  21 . The doors  218  close and open the rear opening  214  of the case  21 . 
         [0020]    A holder  215  is located in the front chamber  211 . The holder  215  includes two posts  2151  extending from an internal face of the case  21 , a frame  2153  and two corner rods  2151  each extending to a corner of the frame  2153  from the root of a related one of the posts  2151 . Each of the posts  2151  has at least one fastener  2154 . 
         [0021]    The stand  23  includes retractable feet  231 . The length of each of the retractable feet  231  is adjustable independent of the others. The stand  23  can thus support the case  21  on different torrential shapes of the ground. 
         [0022]    The temperature controller  3  includes a heater and cooler (not shown) to provide different temperature of air, a first pipe  31  and a second pipe  32 . The heater can be a hot wire that converts electricity into heat. The first pipe  31  sends hot or cold air into the case  21  via the inlet  216 . The second pipe  32  returns the air thereto temperature controller  3  or exhaust from the case  21  through the outlet  217 . 
         [0023]    The measuring unit  4  includes a first cable  41  and a second cable  42 . The first cable  41  is electrically connected to the concentrator photovoltaic module  5  and the second cable  42  is electrically connected to the reference cell  7 . 
         [0024]    The reference cell  7  is also located in the case  21 . A front face of the reference cell  7  is in a same plane with a front face of the concentrator photovoltaic module  5 . 
         [0025]    In operation, the front opening of the case  21  is closed by the gate  22 . The rear opening  214  of the case is opened by operating the doors  218 . The concentrator photovoltaic module  5  is located in the rear chamber  212  through the rear opening  214 . The concentrator photovoltaic module  5  is supported on the frame  2153  and kept there by the fasteners  2154 . The rear opening  214  of the case  21  is closed by the doors  218 . 
         [0026]    The desired air is sent into the case  21  from the temperature controller  3  through the first pipe  36  and the inlet  216 . The air heats or cools the interior of the case  21  and the concentrator photovoltaic module  5 . The air is sent back into the temperature controller  3  from the case  21  through the outlet  217  and the second pipe  32 . Thus, the air is circulated or exhausted and heated or cooled. Accordingly, the temperature of the concentrator photovoltaic module  5  can be increased or decreased to a desired value. The humidity in the case  21  can also be controlled. 
         [0027]    The front opening of the case  21  is opened by operating the gate  22 . The light  11  emits collimated light to the front face of the concentrator photovoltaic module  5  and the front face of the reference cell  7 . The measuring unit  4  measures the current and voltage curve of the concentrator photovoltaic module  5  relative to the reference cell  7 . Furthermore, the measuring unit  4  calculates and shows other characteristics including the open-circuit voltage, the short-circuit current, the maximum-power voltage, the maximum-power current, the maximum power, fill factor and efficiency. The power supply  6  is operable to adjust the intensity of the collimated light emitted from the light  11 . 
         [0028]    With the apparatus of this disclosure, the photovoltaic characteristics of the concentrator photovoltaic module  5  at different temperatures can be measured while the uniformity of the temperature in concentrator photovoltaic module  5  is good. Thus, the temperature coefficient of the concentrator photovoltaic module  5  can be calculated. 
         [0029]    The present disclosure has been described via the detailed illustration of the preferred embodiment. Those skilled in the art can derive variations from the preferred embodiment without departing from the scope of the present disclosure. Therefore, the preferred embodiment shall not limit the scope of the present disclosure defined in the claims.