DefinePK

Abstract

Starter motor converts electrical energy through a battery into mechanical rotating energy. These motors work under heavy load. They produce big power in a short time and in a small volume. If the starter motor fault occurred, the vehicle cannot be run, especially in emergency vehicles (ambulance, fire engine, etc.). Starter motor conveys its rotating energy with a pinion to the flywheel. For initiating internal combustion engine, the rotating moment of starter motors should be requested being greater. The starter motor must be rotating the flywheel at a minimum starting speed. It must also continue support rotation during initial combustion to maintain momentum until the engine can sustain operation. The starter motor turns for approximately 1s during each starting attempt. In each attempt the starter motor gear bounces out and meshes with the flywheel attached to the engine crankshaft. During the compression cycle of each cylinder, the starter motor torque is high, resulting in higher force on the starter gear teeth. Because of the lack of over current protection, the traditional starter control through solenoid easily causes short circuit and bums out starter. So the starter motor and its components are subjected to either mechanical fault like wear, fractures of moving parts or electrical faults like short interrupted circuit and contact resistance increase etc. This paper focuses on causes for various faults and different fault diagnosis methods and also various developments in starter motor fault control are reviewed in detail. The need of electronic control unit based starting system with some of the safety features and online monitoring system for indicating state of charge of battery is also discussed.