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When the main function of the controller is the power control for the protection of the battery, most of the modern devices also include a power conditioning unit..

These power conditioning units are DC-DC converters, which allow to use PV array independently of the battery voltage.

The PVsyst simulation manages 3 different strategies:

- Direct coupling, without power conditioning. This induces constraints on the PV array voltage, and may lead to Pmpp losses  (losse with respect to the Pmpp available power). The Pmpp losses are related to the array voltage (there should be about 36 cells in series for 12V nominal battery voltage), but also to the temperature  (sometimes 40 cells for very hot climates).  Therefore usually only 36 or 72 cells modules are useable in such systems.  

- MPPT converter: the power conditioning ensures the permanent research of the maximum power of the array. This usually allows to  use PV arrays at a higher voltage than the Battery voltage.

- DC-DC converter: this is identical to a MPPT converter, but operating at a fixed input voltage, which simplifies the electronic management. However with the modern development of the electronics we don't find such devices anymore on the market.

When using a power conditioning converter, this device is always included in the controller, and its parameters (similar to the inverter parameter)  are defined in the "Controller" parameters part.

When choosing a commercial regulator, this choice will automatically be updated according to the chosen regulator capabilities.

With the "Default regulator" option, you have to choose the desired operating mode here, in order that the program can select the suited "Generic Default" regulator.