Tracker for maximum power of light-volt electric-power production by solar energy, and control method

Abstract

Characters of the invention are that first, microprocessor obtains information of voltage and current of light-volt array; using algorithm for tracking maximum power in order to determine operating point of light-volt array at next moment; through A / D convertor, the information is converted to reference point Vref. After proportional integral PI adjusts difference value between Vref and sampled actual voltage of light-volt array, PWM control chip generates PWM wave with certain duty ratio to control DC-DC convertor. The method can implement coordinational operation of two branches and multiple branches in plug and play mode. Voltage control mode insensitive to maximum power point is adopted in the invention. Tracking effect is raised by method maximum power point instead of method of current tracking. Being in use for power supply for multiple DC loads, the system is applicable to independent light-volt system as well as to networked light-volt system.

Description

technical field [0001] The invention relates to a solar photovoltaic power generation system, in particular to a tracker and a control method for an independent grid-connected solar photovoltaic power generation system with maximum power tracking. Background technique [0002] With the development of solar photovoltaic power generation, the use of independent operation and grid-connected solar photovoltaic power generation systems has played an important role in solving electricity consumption in remote areas without electricity and relieving energy supply tension in cities. Grid-connected photovoltaic systems are becoming a worldwide Research hotspots. Whether it is an independent operation system or a grid-connected photovoltaic power generation system, how to use the limited space and area to improve the efficiency of the system and obtain the maximum energy is even more important, especially the high price and low efficiency of solar photovoltaic cells. The main reasons...

AI Technical Summary

Problems solved by technology

[0004] (1) The usual maximum power tracker is designed for a specific system, an independent system or a grid-connected system, and does not form a separate device

[0005] (2) The maximum power tracker uses a single-branch structure. When the required power is large, multiple photovoltaic arrays are directly connected to the DC input in parallel. Due to the differences in the characteristics and light-receiving conditions of each photovoltaic array, the photovoltaic array There is also a difference in the maximum power point of the photovoltaic array. If they are directly connected in parallel, there will be a mismatch between the photovoltaic arrays. There are many ways and algorithms, and there are big differences in various ways and algorithms, and there are obvious shortcomings

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