电励磁双凸极无刷直流发电机非线性PI调压技术的研究

Research of Nonlinear PI Voltage Regulation for Doubly Salient Brushless DC Generator

针对12/8极电励磁式双凸极(EMDS)无刷直流发电机的非线性特性,提出了一种新的非线性PI调压控制方法,该算法中比例和积分参数随调压误差的变化而非线性变化。设计了以DSP为核心的数字调压器,利用实验离线辨识的方法建立发电机系统的数学模型,在此基础上设计了算法参数,与传统PI算法做了实验对比,结果表明其抗干扰能力比常规PI调节器强。为了进一步提高系统的动态性能,在非线性PI算法中加入了负载电流前馈补偿控制。实验结果表明,在系统突加和突卸负载两种情况下,采用具有负载电流前馈补偿的非线性PI控制后,发电机电压不仅恢复时间明显缩短,而且电压波动幅值也大大减小,系统的动态性能得到了明显的提高,而且具有高的稳态精度。

A novel nonlinear PI Arithmetic, that is used in voltage regulator of a 12/8 pole electromagnetic doubly salient（EMDS） brushless DC generator which model is high nonlinear, is proposed in this paper. The parameters, P and I, can be adjusted according to the error of output voltage in the new Arithmetic. The mathematics model of generating system is built by off-line identifying based on test data. The parameters in the Arithmetic are designed based on the mathematics model. The digital voltage regulator based on DSP is designed and compared with traditional PI Arithmetic, and the experiment results compared with those based on PI control show the transient and steady state characteristics of generator system are improved. To improve further the dynamic characteristic, the non-linear PI arithmetic with the load-current forward compensating （LCFC） control is also improved. The experiment results show that the nonlinear PI algorithm with LCFC control will make the generator system have the short voltage recovery time, small voltage surge, and good steady state characteristics during loading and unloading transient process.