VS - Electrical Systems From Stop-Start to Hybridization

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Stop-Start management

A stop phase must not jeopardize: ●● Battery state of charge (basically for the next start phase) ●● Braking performances (pressure level in the booster vacuum chamber)

The Stop-Start function implies to precisely monitor the vehicle status prior to engage any action.

Decision to Stop and Start the engine is based on the analysis of many parameters to avoid side effect on safety and discomfort to the vehicle occupants. Engine performances and reliability are as well considered in Stop-Start strategies. Many components are energized by the engine rotation: ●● Alternator ●● Vacuum pump (on diesel engines) ●● Steering pump ●● Oil pump ●● Water pump ●● A/C compressor

●● Steering assistance ●● Engine lubrication ●● Engine cooling

l Cabin comfort

As the basic role of the Stop-Start function is to reduce CO2 emissions, the system supervises as well all conditions that would jeopardize engine combustion quality, among others the engine temperature. The computation of sensors and vehicle status varies according to car makers, engines types and power trains, nevertheless some basic logics remain common to all.

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