Bypass diode for photovoltaic cells

Abstract

A photovoltaic power module, comprising a substrate provided with a circuit, one or more photovoltaic cells mounted to the substrate and electrically connected to the circuit, and one or more bypass diodes, each corresponding to a respective one or more of the cells, wherein each of the diodes is located between the substrate and the cells and between conducting portions of the circuit.

1 . A photovoltaic power module, comprising:
 a substrate thermally couplable to a heat sink;   one or more photovoltaic cells mounted to said substrate;   metallised zones constituting a circuit and provided between said substrate and said cells, said metallised zones being electrically and thermally coupled to said cells; and   one or more bypass diodes each corresponding to a respective one or more of said cells;   wherein each of said diodes is located between said substrate and said cells and at least in part between conducting portions of said metallised zones to permit reduced separation between said cells and said metallised zones and wherein said metallised zones underlie a substantial portion of each of said cells, to facilitate heat flow from said cells to said substrate.   
     
     
         2 . A photovoltaic power module as claimed in  claim 1 , wherein said circuit takes the form of a printed or laminated circuit and each of said diodes is located between neighbouring metallised zones of said circuit. 
     
     
         3 . A photovoltaic power module as claimed in  claim 2 , wherein each of said diodes has a thickness that is substantially equal to or less than the thickness of said metallised zones. 
     
     
         4 . A photovoltaic power module as claimed in  claim 2 , wherein the substrate includes one or more recesses for at least partially accommodating the diodes. 
     
     
         5 . A photovoltaic power module as claimed in  claim 1 , wherein the conducting portions of the circuit are contoured to fit or accommodate said diodes. 
     
     
         6 . A photovoltaic power module as claimed in  claim 5 , wherein each of said diodes has metallised terminals that complement the shape of said conducting portions. 
     
     
         7 . A photovoltaic power module as claimed in  claim 1 , wherein said diodes do not protrude towards said cells beyond said metallised zones. 
     
     
         8 . A photovoltaic power module as claimed in  claim 1 , wherein each of said diodes are thermally coupled to said metallised zones via at least two cooling paths. 
     
     
         9 . A solar concentrator including a photovoltaic power module as claimed in  claim 1 . 
     
     
         10 . A method of bypassing one or more photovoltaic cells in a photovoltaic power module, comprising:
 locating one or more bypass diodes, each corresponding to a respective one or more of said cells, between said cells and the substrate of said module, and at least in part between conducting portions of metallised zones constituting a circuit provided on said substrate between said substrate and said cells;   electrically and thermally coupling said metallised zones to said cells such that said metallised zones underlie a substantial portion of each of said cells in order to facilitate heat flow from said cells to said substrate; and   electrically coupling said bypass diodes to said metallised zones with said bypass diodes arranged to bypass a corresponding one or more cells if a voltage across said corresponding one or more cells drops below a predetermined level or is reversed.   
     
     
         11 . A method as claimed in  claim 10 , wherein the circuit is a printed or laminated circuit. 
     
     
         12 . A method as claimed in  claim 10 , including locating each of said diodes between neighbouring metallised zones of said circuit. 
     
     
         13 . A method as claimed in  claim 10 , including providing each of said diodes with a thickness that is substantially equal to or less than the thickness of said metallised zones. 
     
     
         14 . A method as claimed in  claim 10 , including providing said substrate with one or more recesses for at least partially accommodating said diodes. 
     
     
         15 . A method as claimed in  claim 10 , including contouring portions of the circuit to fit or accommodate said diodes. 
     
     
         16 . A method as claimed in  claim 10 , wherein each of said diodes has metallised terminals that complement the shape of said conducting portions.