An estimation method of maximum power point for solar units in series under uneven lighting conditions

When several solar units are combined into one branch in series, the multi-peak phenomenon of the output power of the branch would be present because of the bypass diode. By analysing the operation principle of the circuit, the number of peak point is decided by all short-circuit currents and maximum power points of all units in series. The way to calculating the number of peak point is designed. Based on the number of peak point a criterion for comparing the value of all peak points is put forward. The criterion put forward are validated by three experiments. This is interesting because the conclusion can make things convenient for designing method of tracking the maximum power of the circuit in series.