Control system and control method for improving output efficiency of photovoltaic array under partial shadow

Abstract

The invention discloses a control system and a control method for improving the output efficiency of a photovoltaic array under partial shadow. The control system comprises a shadow detection module, a DSP (digital signal processing) controller, switch blocks and the photovoltaic array. The shadow detection module is connected with the DSP controller, the DSP controller is connected with the switch blocks, and the switch blocks are connected with the photovoltaic array. The control method includes detecting photovoltaic modules by the aid of the shadow detection module in real time to determine whether the photovoltaic modules are shielded by shadow or not; controlling the switch blocks by the aid of the DSP controller according to detection results of the shadow detection module; swapping the photovoltaic modules which are shielded by the shadow for the photovoltaic modules which are not shielded by the shadow so as to discretize the shadow. The control system and the control method have the advantages that the partial shadow can be discretized, accordingly, negative influence of the partial shadow on integral photovoltaic systems can be reduced, the maximum output efficiency of the photovoltaic array can be improved by 20% approximately, the power generation efficiency of the photovoltaic systems can be effectively improved, and the control system is effective and is easy to implement as compared with modular and reconstructive photovoltaic power generation systems.

Description

technical field [0001] The invention belongs to the technical field of photovoltaic power generation, and in particular relates to a control system and method for improving the output efficiency of a photovoltaic array under partial shadow. Background technique [0002] There are two major problems facing society today—environmental pollution and energy crisis. Environmental problems are clearly presented in front of each of us, such as water pollution around us, smog in Beijing and so on. Petroleum is the most used non-renewable energy by human beings. Due to excessive excavation and exploitation, the problems of surface subsidence and water pollution have been brought about. However, 75% of the energy consumed in our country comes from coal, which has been increasingly depleted and has brought various environmental pollution problems. , Various problems brought about by the massive exploitation and utilization of these non-renewable energy sources have sounded the alarm to...

AI Technical Summary

Problems solved by technology

Later, some literatures proposed a reconfigurable photovoltaic power generation system, that is, the photovoltaic array is divided into a fixed part and a movable part. The constructed photovoltaic array does not have any shading, so as to achieve the purpose of improving efficiency, but in the absence of partial shading, the active part is idle, wasting resources and increasing costs

[0004] To sum up, the existing methods to improve the efficiency of photovoltaic systems under partial shading have their own shortcomings, and the method of only using parallel bypass diodes and blocking diodes is simple, but its effect is not obvious; Photovoltaic power generation systems require more DC-DC converters, which increases the cost sharply; and the reconstructed photovoltaic power generation system generates idle photovoltaic arrays under sunny conditions, which also increases the cost.

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