High Efficient Intelligent Motor Control for a Hybrid Shunting Locomotive

Abstract

So many shunting locomotives are used all around the world. In order to save fuel and reduce pollution, they can be converted to Hybrid Electric Locomotives (HELs). In this paper, the selection and use of the induction electric machines for energy conversion in a plug in Hybrid Electric Locomotive is introduced. An old G12 locomotive is renovated and converted to a hybrid electric locomotive. To drive the locomotive, two induction motors are placed in two of the four axles of the locomotive. Due to the funding limits of the project, a prototype with two small motors was built. The G12 locomotive has four axles. Therefore, if the locomotive is mass produced, up to four motors with higher power ratings may be used that will give up to five times more torque and power. Instead of a 750 kVA diesel generator, a 80 kW diesel engine and a 50 kVA generator is used. Two 1200 volt, 300 ampere inverters with IGBT modules are used to drive each motor of the locomotive. The inverters are supplied by 480 volt, traction lead acid batteries. There are three ECUs for the motor and locomotive control. One is a master controller and to drive the LCD panels and the two others are for the inverter controllers. During the day, a shunting locomotive has around 60% idle time. In this condition, the locomotive consumes fuel and as its engine works at no load, the efficiency is zero and pollution is very high. A diesel engine in a hybrid technology either will be off or run at its rated torque and power. Therefore, its efficiency is high and at the same time the pollution and the fuel consumption are reduced a lot. The engine will be off unless the battery state of charge (SOC) reduced to a certain level. Moreover, instead of a 750 kVA diesel engine a 50 kVA diesel generator is used.