摘要
温差发电(thermoelectric generation,TEG)系统作为一种清洁可再生的新能源发电装置,通过最大功率点跟踪(maximum power point tracking,MPPT)控制器连续跟踪输出功率的最大值极其重要。针对TEG系统侧存在功率振荡、功率跟踪速度慢、跟踪精度差等问题,文中在硬件电路上对比了不同DC-DC变换器的特点,选定能减缓功率振荡的二次型Boost电路作为MPPT的主电路。同时,在MPPT的算法策略上,文中提出一种基于优化初值的增量电导法(OI-INC),首先,通过分析TEG的电流—电压输出特性和二次型Boost电路的等效模型,计算并输出近似的最优占空比,快速跟踪到最大功率点附近,优化增量电导法的初值;之后,采用较小的扰动步长实现高质量MPPT。在含有启动、恒温、均匀升温、快速升温4种工况的复杂时变环境下,与扰动观察法、增量电导法相比,仿真结果表明:文中所提出的MPPT策略不仅能压缩跟踪时间、提高跟踪精度,还能减轻功率振荡问题。
As a clean and renewable new energy generation device,it is very important for thermoelectric generation(TEG)system to continuously track the maximum output power through the maximum power point tracking(MPPT)controller.In view of such problems as power oscillation,slow power tracking speed and weak tracking accuracy in TEG system,the characteristics of different DC-DC converter is compared on the hardware circuit in this paper,and the quadratic Boost circuit,which can mitigate power oscillation,is selected as the main circuit of MPPT.At the same time,in the algorithm strategy of MPPT,a kind of incremental conductance method based on initial value optimization(OI-INC)is proposed.Firstly,the approximate optimal duty cycle is calculated and output by analyzing the current-voltage output characteristics of TEG and the equivalent model of the quadratic Boost circuit.The initial value of the incremental conductance method is optimized with fast tracking to the maximum power point.Then,the high quality MPPT is achieved with small disturbance step size.Comparison with the perturbation and observation method as well as the incremental conductance method is made under such four complicated variation environments as initiation,constant temperature,uniform temperature rise and fast temperature rise.The simulation result shows that the MPPT strategy proposed in this paper can not only compress the tracking time,improve the tracking accuracy,but also reduce the power oscillation.
作者
韩翔宇
纽春萍
何海龙
田昊洋
彭伟
HAN Xiangyu;NIU Chunping;HE Hailong;TIAN Haoyang;PENG Wei(State Key Laboratory of Electrical Insulation and Power Equipment,Xi’an Jiaotong University,Xi’an710049,China;State Grid Shanghai Electric Power Research Institute,Shanghai200000,China)
出处
《高压电器》
CAS
CSCD
北大核心
2023年第11期240-249,共10页
High Voltage Apparatus
基金
国家电网有限公司科技项目(面向能源互联网自供电传感关键技术研究)。
关键词
温差发电系统
最大功率点跟踪
DC-DC变换器
增量电导法
thermoelectric generation system
maximum power point tracking
DC-DC converter
incremental conductance method
