一、方法原理与技术框架
1. 小波分析在电网数据预处理中的作用
- 噪声抑制:通过多尺度分解(如DWT)分离高频噪声与低频有效信号,提升潮流计算输入数据的精度
- 特征提取:提取电压/电流信号的突变特征(如暂态过程),用于优化约束条件构建
- 数据压缩:对PMU量测数据进行小波包压缩,减少优化变量维度
2. 粒子群算法(PSO)优化流程
- 目标函数:最小化网损或电压偏差
- 决策变量:发电机出力、无功补偿容量、变压器分接头位置
- 约束处理: 电压越限约束:
0.95 ≤ V_i ≤ 1.05 pu发电机出力限制:P_Gmin ≤ P_G ≤ P_Gmax功率平衡约束:ΣP_G = ΣP_D + P_loss
3. 算法融合策略
% 小波预处理模块
[C_L, L] = wavedec(PMU_voltage, 5, 'db4'); % 5层db4小波分解
denoised_voltage = waverec(C_L .* threshold(L), L, 'db4'); % 阈值去噪
% PSO优化模块
nVar = 10; % 变量维度(如10个DG节点出力)
lb = [0.1*ones(1,5), 0.05*ones(1,5)]; % 下限
ub = [0.9*ones(1,5), 0.3*ones(1,5)]; % 上限
[best_pos, best_cost] = PSO(@fitness, nVar, lb, ub, 100, 30);
二、MATLAB实现核心代码
1. 小波去噪与特征提取
function clean_data = wavelet_denoise(raw_data)
% 参数设置
wname = 'sym8'; % 对称小波基
level = 4; % 分解层数
% 多级分解
[c, l] = wavedec(raw_data, level, wname);
% 阈值选择(VisuShrink方法)
sigma = median(abs(c))/0.6745;
thr = sigma*sqrt(2*log(length(raw_data)));
% 硬阈值处理
denoised = wthresh(c, 's', thr);
% 重构信号
clean_data = waverec(denoised, l, wname);
end
2. 粒子群算法优化模块
function [gbest, gbest_cost] = PSO(fitness, nVar, lb, ub, maxIter, swarmSize)
% 初始化粒子群
particles = repmat(lb, swarmSize, 1) + rand(swarmSize, nVar) .* repmat(ub-lb, swarmSize, 1);
velocities = 0.1*(ub-lb) .* rand(swarmSize, nVar);
% 个体最优与全局最优
pBest = particles;
pCost = arrayfun(@(i) fitness(particles(i,:)), 1:swarmSize);
[gCost, gIdx] = min(pCost);
gBest = pBest(gIdx,:);
% 参数设置
w = 0.729; % 惯性权重
c1 = 1.49445; % 个体学习因子
c2 = 1.49445; % 社会学习因子
% 迭代优化
for iter = 1:maxIter
for i = 1:swarmSize
% 速度更新
velocities(i,:) = w*velocities(i,:) ...
+ c1*rand(1,nVar).*(pBest(i,:) - particles(i,:)) ...
+ c2*rand(1,nVar).*(gBest - particles(i,:));
% 位置更新
particles(i,:) = particles(i,:) + velocities(i,:);
particles(i,:) = max(particles(i,:), lb);
particles(i,:) = min(particles(i,:), ub);
% 适应度更新
cost = fitness(particles(i,:));
if cost < pCost(i)
pCost(i) = cost;
pBest(i,:) = particles(i,:);
end
end
% 更新全局最优
[current_gCost, current_gIdx] = min(pCost);
if current_gCost < gCost
gCost = current_gCost;
gBest = pBest(current_gIdx,:);
end
% 进度显示
fprintf('Iter %d | Best Cost: %.4f\n', iter, gCost);
end
end
3. 潮流计算与目标函数
function cost = fitness(x)
global busdata linedata
% 解析决策变量(示例:5个DG节点出力)
P_DG = x(1:5);
Q_DG = x(6:10);
% 修改节点数据
busdata(:,8) = P_DG; % 有功注入
busdata(:,9) = Q_DG; % 无功注入
% Newton-Raphson潮流计算
[V, delta, P_loss] = nrloadflow(busdata, linedata);
% 目标函数:最小化网损 + 电压偏差惩罚
cost = P_loss + 1000*sum(max(0, abs(V)-1.05) + max(0, 0.95-abs(V)));
end
参考代码 基于小波分析,粒子群算法的在matlab开发环境中的电网潮流优化 www.youwenfan.com/contentcso/96290.html
三、优化
1. 自适应参数调整
-
惯性权重动态调整:
w = w_max - (w_max - w_min)*(iter/maxIter); % 线性递减 -
混沌初始化:用Logistic映射生成初始粒子群,提升全局搜索能力
2. 多目标优化扩展
% 帕累托前沿提取
ParetoFront = [];
for i = 1:size(particles,1)
cost = [fitness(particles(i,:)), voltage_deviation(particles(i,:))];
ParetoFront = [ParetoFront; cost];
end
ParetoFront = unique(ParetoFront, 'rows');
3. 并行计算加速
% parfor替代for循环
parfor i = 1:swarmSize
% 并行计算适应度
cost = fitness(particles(i,:));
end
四、算例验证(IEEE 30节点系统)
1. 数据准备
% 节点数据加载(示例)
busdata = [
1 1 1.06 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
311

被折叠的 条评论
为什么被折叠?



