Solar Panel Protection Diode

Blocking diodes are used to prevent your batteries from discharging backwards through your solar panels at night.

Solar panel protection diode.

In multi panel pv strings the faulty panel or string has been bypassed by the diode which provide alternative path to the flowing current from solar panels to the load. In practise we use larger groups of solar cells. Blocking diodes will be of benefit in any system using solar panels to charge a battery. They are also used as bypass devices to maintain the reliability of the entire solar power system in the event of a solar panel failure.

When a single solar cell is shaded this configuration is optimal. In string 1 each solar cell has its own bypass diode. The schottky bypass diodes used in most cell based solar panels serve as a protection mechanism that allows the panel to continue producing power when one of its cell strings is shaded or damaged. Again current flows from high to low voltage so during a sunny day the voltage of a solar panel will be higher than the voltage of a deep cycle battery and the current will naturally flow from the panel to the battery.

Diodes are extensively used in solar panel installations. Bypass diode in a solar panel is used to protect partially shaded photovoltaic cells array inside solar panel from the normally operated photovoltaic string in the peak sunshine in the same pv panel. Now let s consider what happens if one of the panels in the above diagram is shaded. Blocking diodes are usually included in the construction of solar panels so further blocking diodes are not required.

When two adjacent solar cells are shaded string 2 gives a higher output voltage 0 82v instead of 0 53v.