演讲稿
.rtf
School
University of Birmingham**We aren't endorsed by this school
Course
CS 23899
Subject
Electrical Engineering
Date
Dec 19, 2024
Pages
2
Uploaded by BaronWillpowerAardvark43
As we all know, in the current global energy context, we are facing an energy crisis alongside increasing carbon emissions. This has led to an urgent need for renewable energy solutions. Among many renewable energy sources, solar energy stands out due to its sustainability and environmental benefits. But how can we ensure solar energy’s efficiency, applicability, and stability? We have considered using Maximum Power Point Tracking (MPPT) technology, such as P&O or GMPPT, among others, to help us maximize the energy harvested from photovoltaic (PV) systems.Let’s talk about MPPT.As we all know,The V-I characteristic and P-V characteristic of PV panels are NON-LINEAR due to it’s operating principle.We can see the figure on the left,it is a P-V characteristic curve of a typical PV panel.As voltage increases,power first rises until it reaches the peak which is the maximum power point and then begin to decrease. What’more, the I-V and P-V curves change with environmental factors like the right graph shows:as the solar radiation and temperature increase, both the current and the maximum power output will increase, resulting in different maximum power points.This means that different curves correspond to different maximum power points.In this case, MPPT technology can be used to find the real-time maximum power point as environmental factors change.Perturb and Observe (P&O) is a commonly used Maximum Power PointTracking (MPPT) method. It can track and approach the maximum powerpoint(MPP) by making small disturbances to the voltage while the system isworking and observing the power trend.We can understand its workingprinciple through the flowchart on the right.First,measure the voltage (V)and current (I) from the PV panel to calculate the power (P).And thencompare the current power (P) with the previous value to determine if powerhas increased or decreased.Then adjust the voltage accordingly: if powerincreases, continue in the same direction; if power decreases, change thedirection of the voltage perturbation. This helps to approach and maintainthe system at the maximum power point (MPP).P&O have lots ofadvantages,like easy to use,simple to calculate and wide to apply.Butconsider about Accuracy Stability and time.It also have lots of challenges.I listed three key challenges P&O facing and their impact.One of the main issue is that it may get stuck at a local maximum, especially in shaded
conditions.Additionally, near the maximum power point, the P&O method can cause oscillations, which lead to power losses. Furthermore, P&O has limited response speed, making it difficult to adapt to rapid changes in environmental conditions.These challenges have several impacts on system performance. First is efficiency loss,where oscillations and getting stuck in local maxima reduce overall efficiency.The second impact is Instability, caused by the slow response, leading to unstable power output. Lastly, Optimization Neededindicates that improvements or hybrid methods are necessary to enhance system performance.Our group member Hu will describe these challenges in detail below.