The MPPT operating voltage range for most string inverters is between 80V and 600V, depending on the inverter make and model. The voltage range for Solar MPPT charge controllers is generally much lower and varies from 24V up to 250V.
[pdf] This report from GridLab provides an introduction to voltage regulation concepts, including advantages and disadvantages of various control modes. The authors include lessons learned from studies and demonstration pilots and also provide recommendations for utilities.
[pdf] Sometimes the system voltage required for a power plant is much higher than what a single PV module can produce. In such cases, N-number of PV modules is connected in series to deliver the required volt.
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