How to prevent solar cells from heating up in household PV power plants?

If the power station being tested is not timely in operation and maintenance, there are mud, bird droppings, leaves, etc., and these obstructions form partial shadows on the battery components, and the current and voltage of some battery cells in the assembly change. As a result, the product local current and voltage product is increased, resulting in a local temperature rise on these battery components. In addition, some of the battery's own defects in the module may also cause the component to heat locally during operation. This phenomenon is called "hot spot effect". Hot spot effect: refers to the solar cell module that is shielded in the series branch will act as a load and consume the energy generated by other illuminated solar cell modules under certain conditions. The blocked solar cell module will heat up at this time. phenomenon.

The hazard of the hot spot effect: the occluded photovoltaic components, part of the energy or all energy generated by the photovoltaic components that will consume the light, reduce the output power; severely will permanently damage the solar cell components, and even burn components.

The reasons for this: First, the root cause of the hot spot effect is the mixing of individual bad batteries, the electrode solder joints, the battery from crack to breakage, the deterioration of individual battery characteristics, and the partial blocking of the battery. Second, due to the existence of local shadows, the current and voltage of some battery cells in the solar cell module have changed. As a result, the product of the local current and voltage of the solar cell module is increased, thereby causing a local temperature rise on these battery modules.

Protective measures: Connect a bypass diode between the positive and negative terminals of the solar cell module to increase the reliability of the square matrix. Normally, the bypass diode is reverse biased and does not affect the normal operation of the component.

Principle: When a battery is blocked, other batteries cause it to become a large resistance. At this time, the diode is turned on, and the portion of the total battery that exceeds the photocurrent of the blocked battery is shunted by the diode, thereby preventing the covered battery from being overheated and damaged. To avoid the energy generated by the illumination component being consumed by the shielded component.