Photovoltaic power structure and maximum power tracking control method

Abstract

The invention discloses a photovoltaic power structure and a maximum power tracking control method. The photovoltaic power structure comprises a photovoltaic assembly, BOOST circuits and a maximum power tracking control unit. An A output terminal and a B output terminal of the photovoltaic assembly are connected with the BOOST circuits respectively. Output terminals of the two BOOST circuits are connected in series and then are connected in parallel with a capacitor. A backward stage of the capacitor is grid-connected through a grid-connected system. The maximum power control unit compares output voltages of the two BOOST circuits. A difference value is converted into a corresponding duty ratio through a PI regulator. Then the duty ratio is converted into a corresponding PWM wave so that output power of the photovoltaic assembly is dynamically adjusted. And finally the photovoltaic assembly works stably at a maximum power point. By using the method, control is simple; a current sensor, memory and a microprocessor are not needed; only a simple circuit is needed so that maximum power tracking can be realized; cost can be greatly reduced.

Description

technical field [0001] The invention belongs to the technical field of photovoltaic power generation, and relates to a photovoltaic power source structure and a maximum power point tracking control method. Background technique [0002] Energy is the material basis for developing the national economy and improving people's living standards. With the development of economy and society, traditional fossil energy is decreasing day by day, and it has become an inevitable trend of energy development to seek new energy to replace fossil energy. Solar energy has many advantages such as huge reserves, no need for mining and transportation, and no regional restrictions. Therefore, among all new energy power generation, solar power generation has a prominent position and obvious advantages. It has important research value and broad application prospects. [0003] Photovoltaic power generation is the dominant form of solar power generation. In the photovoltaic power generation system,...

AI Technical Summary

Problems solved by technology

The perturbation and observation method is a traditional maximum power point tracking control method. It needs to use current sensors and voltage sensors at the same time, and also needs to use memory to store the data at the previous moment. The circuit structure is complex and the cost is high.

And when the light intensity is very low, it is also prone to failure

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