| 摘要: |
| 目的 对于级联 H 桥逆变器的调制,特定谐波消除技术具有开关损耗小,能够消除特定次谐波,变换效率高
等优点,但传统粒子群优化算法(Particle Swarm Optimization,PSO)在求解消谐方程组时收敛性差,容易局部最优,
提出一种改进的粒子群优化算法(Modified Particle Swarm Optimization,MPSO)。 方法 该算法用非线性惯性权重取
代线性变化的惯性权重,并在非线性惯性权重引入混沌映射以产生随机性更好的随机量,新的惯性权重可权衡粒
子的全局搜索和局部搜索能力,使粒子具有后期跳出局部最优的能力;另外,该算法优化了速度和位置的更新机
制,以增强算法的收敛速度,并保证粒子在后期仍具有一定种群多样性优势。 结果 根据级联 H 桥型逆变器的非线
性消谐方程组,在保证输出电压基波的前提下最大化降低目标次谐波,建立适应度函数,将 MPSO 算法应用于级联
H 桥型逆变器的 SHEPWM,能够在 1~1. 2 的调制度范围内得到优化的开关角,提高收敛精度和求解成功率。 通过
七电平 CHB 逆变器仿真平台验证了 MPSO 算法所求的优化开关角能够有效地消除 5 次、7 次谐波。 结论 通过使用
非线性惯性权重和优化粒子的速度和位置更新机制,可以增加开关角求解成功率,所得解可以有效地消除目标次
谐波。 |
| 关键词: 特定谐波消除 开关角 消谐方程组 惯性权重 收敛精度 |
| DOI： |
| 分类号: |
| 基金项目: |
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| Research on Selective Harmonic Elimination Technology Based on MPSO Algorithm |
|
ZENG Qinghong
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School of Electrical and Information Engineering, Anhui University of Science and Technology, Anhui Huainan 232001,
China
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| Abstract: |
| Objective Regarding the modulation of cascaded H-bridge inverter the selective harmonic elimination
technology has the advantages of low switching loss elimination of specific subharmonics and high transformation
efficiency. However the traditional particle swarm optimization PSO algorithm has poor convergence and is easy to be
locally optimized when solving harmonic elimination equations. A modified particle swarm optimization MPSO algorithm
was proposed. Methods In this algorithm the nonlinear inertia weight was used to replace the linear inertia weight and
chaotic mapping was introduced into the nonlinear inertia weight to produce the random quantity with better randomness.
The new inertia weight can balance the global search ability and local search ability of particles so that particles have the
ability to jump out of the local optimum in the late stage. In addition the algorithm optimized the updating mechanism of
speed and position to enhance the convergence speed of the algorithm and to ensure that the particles still have a certain
population diversity advantage in the later stage. Results According to the nonlinear harmonic elimination equations of
cascaded H-bridge inverter the fitness function was established to ensure the maximum reduction of the target harmonic
under the premise of the output voltage base wave. When applied to SHEPWM of cascaded H-bridge inverter MPSO
algorithm obtained optimized switching angle in the range of 1 ~ 1. 2 adjustment system. Compared with the PSO algorithm MPSO can improve the convergence accuracy and solving success rate. The seven-level CHB inverter
simulation platform verified that the optimized switching angle obtained by MPSO algorithm can effectively eliminate the
5th and 7th harmonics. Conclusion By using the nonlinear inertia weight optimizing the velocity of particles and
applying position update mechanism of particles the success rate of switch angle solution can be increased and the
obtained solution can effectively eliminate the target subharmonics. |
| Key words: selective harmonic elimination switching angles harmonic elimination equations inertia weight convergence precision |
