Intelligent photovoltaic module controller and control method thereof

An intelligent photovoltaic module controller for switching electrical connection between photovoltaic modules each comprising multiple solar cells connected to one another, the intelligent photovoltaic module controller comprising:

• a first pair of input terminals electrically connected to positive (+) and negative (−) terminals of a first photovoltaic module, respectively;
• a second pair of input terminals electrically connected to positive (+) and negative (−) terminals of a second photovoltaic module, respectively;
• a pair of positive (+) and negative (−) external connection terminals electrically connected to a power converter or electrically connected in series to another intelligent photovoltaic module controller;
• a series circuit connected between the first pair of input terminals, the second pair of input terminals, and the pair of external connection terminals such that one terminal of the first pair of input terminals is electrically connected to one terminal of the second pair of input terminals having an opposite polarity thereto and the other terminals of the first and second pairs of input terminals are electrically connected to the positive (+) and negative (−) external connection terminals, respectively;
• a parallel circuit connected between the first pair of input terminals, the second pair of input terminals, and the pair of external connection terminals such that the positive (+) and negative (−) terminals of the first pair of input terminals are electrically connected to the positive (+) and negative (−) terminals of the second pair of input terminals, respectively, which, in turn, are electrically connected to the positive (+) and negative (−) external connection terminals, respectively;
• a switch circuit performing switching operation to connect a selected one of the series circuit and the parallel circuit between the first pair of input terminals, the second pair of input terminals, and the pair of external connection terminals;
• and
• a control unit controlling the switch circuit to perform switching between series connection and parallel connection,
• wherein, when electrical connection between the first and second photovoltaic modules is switched from the series circuit to the parallel circuit, determination as to whether to switch electrical connection between the first and second photovoltaic modules back to the series circuit is made based on changes in current flowing through the pair of external connection terminals or a string connected to the pair of external connection terminals due to switching to the parallel circuit.