以DSP為基礎的直流馬達電能回充之研製及其在電動機車上的應用

Abstract

在台灣，電動機車可能是解決都會地區空氣污染問題最有效的方法之一，而電動機車的關鍵技術包括：馬達、控制器及電池。本論文針對目前電動機車中最常使用的兩種馬達：單相直流有刷馬達及三相直流無刷馬達，利用數位訊號處理器TMS320F243強大的控制器架構，以升壓式轉換器的原理，將電動機車於煞車時所產生的動能，以再生發電的方法，將動能轉換為電能，回收儲存於電池，應用此一方法不但可延長電動機車一次充電下行駛的里程，並有類如“引擎煞車”的功能。我們所設計的電流回授控制電路，著眼在回充至電瓶的平均回充電流，利用簡單的架構即可完成動能越大，回充電流也隨之越大的功能。在文中，除了對馬達、功率開關及鉛酸電池做完整的等效電路模型分析外，並以模擬及實驗結果證明電能回充電路工作良好且與理論吻合。現階段的實驗結果，有刷馬達轉速為2880rpm時，回充電流可至5.6A；無刷馬達轉速為4800rpm時，回充電流可至6A。

In Taiwan, using the electric motorcycle as a vehicle is one of the most effective approaches to solve the problem of air pollution in the urban areas. The key technologies of an electric motorcycle encompass battery, motor, and controller. In this thesis, we have designed a controller based on a TMS320F243 DSP chip to control the average recharge current of a single-phase DC brushed motor and a three-phase DC brushless motor. We use the step-up converter operating theory to transfer the kinetic energy to the electrical energy returned to the batteries. The scheme has the advantages of extending the travel range between recharges and emulating the “engine braking” function. A current control feedback circuit which has a simple structure focuses on the average recharge current returned to the batteries. And it is designed so that the charging current varies with the system kinetic energy. In this paper, the equalized circuit models of motors, power switches and lead-acid batteries are analyzed in detail, and proved our energy restoring circuit works very well and meets the theoretic estimation both in simulations and experimental results. In present experimental results the recharge current is 5.6 A when the brushed motor rotation speed is 2880 rpm, and the recharge current is 6 A when the brushless motor rotation speed is 4800 rpm.