Segmentation self-adapting hill climbing method and system applied for tracing maximum power of photovoltaic cell

Abstract

The invention provides a segmentation self-adapting hill climbing method and a system thereof applied for tracing maximum power of a photovoltaic cell. The method comprises: finding the zone of the current power by partitioning the output power of the photovoltaic cell and comparing power difference of two adjacent moments with a set value; then, adjusting duty cycle to measure the power of the next moment until the maximum power point is found. The system of the invention comprises a photovoltaic cell, a DC/DC converter and a plumbic acid storage battery which are connected by circuits in sequence, wherein, a circuit between the DC/DC converter and the plumbic acid storage battery is provided with a voltage detecting module and a current detecting module, the output ends of the voltage detecting module and the current detecting module are respectively connected with a microprocessor, and the output end of the microprocessor is connected with the DC/DC converter via an isolation/ driving circuit. The invention quickens the tracing speed of the maximum power point, improves the anti-interference performance of the system, quickens the self-optimizing process of the maximum power point of the system and decreases the oscillation of the system at the maximum power point.

Description

technical field [0001] The invention relates to the control technology of solar photovoltaic cells, in particular to a segmented self-adaptive hill-climbing method and system applied to maximum power tracking of photovoltaic cells. Background technique [0002] With the rapid development of social economy, the consumption of energy and resources is getting faster and faster. Energy conservation and environmental protection have become the focus of sustainable development, and human attention has shifted from conventional energy to renewable energy, such as solar energy, wind energy, and tidal energy. With the rapid development of solar technology, solar energy is an inexhaustible green energy, and solar energy has become a hot spot in various fields of scientific research and production. [0003] From the I-V curves of photovoltaic cells under different temperatures and different sunlight intensities, it can be seen that temperature mainly affects the output voltage of phot...

AI Technical Summary

Problems solved by technology

People have conducted in-depth research on the maximum power tracking technology, and now a variety of algorithms have been obtained, and the most widely used method is the perturbation and observation method, such as figure 1 As shown in the flow chart, the maximum power point of the photovoltaic cell is tracked by comparing the power difference between two adjacent moments with the set constant e. This method is simple, but there is an adjustment step when adjusting the duty cycle D The problem of size selection, that is, if the step size is too small, the tracking time will be longer, which will affect the dynamic response characteristics of the system; when the step size is too large, the output power fluctuation will increase, the average value will be much smaller than the maximum value, and the steady-state error will become larger; This makes it difficult to guarantee the dynamic and steady-state performance of the system

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