金楠 窦智峰 李琰琰 孔汉 陶涛

摘要：为提高清洁能源电能转换效率和并网电能质量，对于电压源并网变换器，提出一种优化的模型预测电流控制策略。首先，在αβ坐标下建立控制模型，仅使用一次坐标变换，设计出无需脉冲宽度调制（PWM）和电流内环控制的有限控制集模型电流预测控制（FCS MPCC）策略，控制灵活简单。其次，对代价函数进行优化设计，增加开关频率附加项并设计权重系数，实现降低开关频率。针对执行预测控制算法产生的延时，设计两步预测模型进行电流预测，实时更新开关状态。为验证控制策略性能，搭建实验平台。实验结果表明，所设计控制策略能够灵活调节输出功率因数，具有较高的输出电能质量且开关频率降低、并网性能良好。

关键词：电压源并网变换器;模型预测电流控制;延时补偿;降低开关频率;代价函数

DOI：10.15938/j.emc.2019.09.016

中圖分类号：TM 46

文献标志码：A

文章编号：1007-449X（2019）09-0123-08

Finite control sets predictive current control of voltage  source grid connected converter

JIN Nan1，DOU Zhi feng1，LI Yan yan1，KONG Han1，TAO Tao2

（1.College of Electrical Engineering， Zhengzhou University of Light Industry， Zhengzhou 450002， China; 2. Xuchang Power Supply Company of State Grid， Xuchang 461000， China）

Abstract：

In order to enhance the power conversion efficiency and power quality， an improved current predictive model of the voltage source grid connected converter was proposed. Firstly， the model in the two phase static αβ frame was established. Without using pulse width modulation （PWM） and inner loop current control， a kind of easy implemented finite control states model predictive coordinated control （FCS MPCC） for grid connected control was designed. Furthermore， the switching frequency plenty item was added to the cost function. The switching frequency is reduced by optimizing the cost function and regulating the weighing factor. In addition， when the sampling frequency is high， the delay of control algorithm execution will influence the system performance. The two step current prediction model was designed to ensure timely update switching states of power devices. The experimental platform was designed. The experimental results show that MPCC strategy can reduce the switching frequency effectively， improve the power quality and adjust power factor with good dynamic performance.

Keywords：voltage source grid connected converter; model predictive current control; delay compensation; switching frequency reduction; cost function

0引言

随着环境污染和能源结构调整等问题日益突出，清洁能源发电将成为未来电力生产的重要组成部分。电压源并网变换器是新能源并网发电的关键设备，其可靠运行是并网发电的核心研究，良好的控制性能至关重要。

有限控制集模型预测控制（finite control sets model predictive control， FCS MPC）区别于传统前馈解耦脉冲宽度调制（pulse width modulation，PWM）控制方法，具有适应性良好、鲁棒性强、包含多约束变量等优点，且不需使用双环控制和PWM调制环节。对于三相并网逆变器及三电平并网逆变器，模型电流预测控制策略实现了较好的控制效果。……