Abstract: The invention relates to method (19) of cooling a heat generating device (2). The cooling rate (17, 18) of said heat generating device (2) is determined, at least in part and/or at least at times, based on the rate of change of temperature (16) of the heat generating device (2).

Abstract: The present invention relates to a method of operating a maximum power point tracker comprising the steps of performing a sweep cycle at intervals, the sweep cycle comprising the determination of at least one first parameter of a power function, storing the at least one first parameter and at least one second parameter and, based on the data so stored, modifying one or more characteristics of the sweep cycles. The invention also relates to a maximum power point tracking apparatus comprising a controller (12, 115) suitable for controlling an operating parameter, an input (4, 104) connected to a power source (3, 103) and a data store (15, 115), which apparatus is suitable for being operated by the above method.

Abstract: In large PV power plants, grounding of individual PV modules may lead to problems. The present invention overcomes such problems. The basis for the invention is a PV power plant comprising one or more PV generators, each comprising a PV string and an inverter with a DC input and an AC output. The PV string comprises at least one PV module and is electrically connected to the DC input of the inverter. The inverter comprises means for controlling the DC potential at the DC input depending on the DC potential at the AC output. The AC outputs of the inverters are coupled in parallel. The novel feature of the invention is that the PV power plant further comprises an offset voltage source, which controls the DC potential at the AC outputs. Thereby, the DC potential at the DC input will be indirectly controlled, and it is thus possible to ensure that the potentials with respect to ground at the terminals of the PV modules are all non-negative or all non-positive without grounding the PV modules.