Maximum Power Point Tracking Control Method Based on Incremental Conductance Method and Particle Swarm Optimization

Abstract

The invention relates to a maximum power point tracking control method based on conductance incremental method and particle swarm algorithm, comprising the following steps: fast start-up stage: adding a stagnation time when starting, and the DC-DC circuit of the photovoltaic system stops working within the stagnation time ;Tracking stage with variable step size: judge the disturbance direction according to the positive or negative of dP / dU, and judge the disturbance step size by the size of |dP / dU|; where, dP is the output power variation, dU is the output voltage variation; dynamic particles Stable stage of swarm algorithm: when |dP / dU| is less than the start threshold of dynamic particle swarm optimization, it enters dynamic particle swarm optimization, and the best value found is the optimal output voltage U best , when the fitness value is satisfied or the maximum number of iterations is reached, the optimal output voltage U best . The invention can greatly improve the tracking time, tracking accuracy and response speed.

Description

technical field [0001] The invention relates to the technical field of maximum power point tracking of photovoltaic systems, in particular to a maximum power point tracking control method based on conductance incremental method and particle swarm algorithm. Background technique [0002] With the depletion of traditional fossil energy, clean and environmentally friendly solar energy has become an important part of the energy field. Solar cells can convert solar energy into electrical energy. When the irradiance and temperature change, the output voltage and output current of solar cells will change, showing nonlinear output characteristics. In order to improve the conversion efficiency of photovoltaic modules, through the corresponding control strategy to make the photovoltaic modules always work at the maximum power point, this process is the maximum power point tracking (abbreviated as MPPT) technology, MPPT technology has become an important part of the photovoltaic system...

AI Technical Summary

Problems solved by technology

At present, the commonly used MPPT methods include constant voltage method, perturbation and observation method and conductance incremental method. The above methods are limited by the fixed perturbation step size and cannot take into account the requirements of tracking time, tracking accuracy and response speed.

The control of the constant voltage method is simple and the implementation cost is low, but the influence of temperature on the output characteristics of the solar cell is ignored, and dynamic tracking cannot be realized

The perturbation and observation method is simple and easy to implement, but due to the limitation of the step size, it will oscillate near the maximum power point, the system power loss is large, and the tracking accuracy is poor

The conductance incremental method is similar to the disturbance observation method and can track dynamically, but it is also limited by the fixed disturbance step size, which cannot meet the requirements of tracking time, tracking accuracy and corresponding speed at the same time.

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