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<< Click to Display Table of Contents >> DC grid: Overvoltage regulation |
  
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<< Click to Display Table of Contents >> DC grid: Overvoltage regulation |
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The output voltage at the PV field terminals is the end-user's voltage (bus, tramway), to which is added the line loss corresponding to the PV current through the line resistance PV-to-user. When the user's needs become too weak, this voltage will increase following to the PV array I/V characteristics, and may reach the array Voc value if there is no more load at all. It is therefore necessary to introduce a regulation system, avoiding the possibility that this voltage goes over the maximum admissible voltage for the network.
This regulation can operate according to 3 different modes:
- Global cut of the PV system,
- Progressive decrease of the PV power by cutting off some strings of modules,
- Progressive decrease by cutting off some modules in each string (which is not a very practical solution).