Research on Phase Synchronization Strategies for Diesel Engines to Startup Quickly

Abstract

Valid and quick phase synchronization is essential to diesel engine operation, with impacts on the starting time and emissions. This paper presents an innovative wheel shape of camshaft with four long teeth and four short teeth, which plays a fundamental role in the proposed phase synchronization strategies. A dynamic validity-check algorithm of camshaft and crankshaft sensor signals is developed as a premise. Specifically, the segment pattern matching method is used in the rapid phase synchronization strategy that is applicable given valid camshaft and crankshaft signals. A combination of trial injections and the pattern matching method is applied when either the camshaft or crankshaft sensor signal is missing in the limp home mode. Bench test results showed that phase synchronization could be realized within 180 crankshaft angles, and that the phase synchronization strategies in the limp home mode were feasible.