Bosch's Start/Stop Technology13 July 2008
Bosch start/stop technology has proven its worth in production applications, supplying half a million starter-based start stop systems to BMW and MINI since the introduction in 2007. Three further vehicle manufacturers have decided to use this cost-effective and efficient Bosch technology, and are planning a roll-out within the next few months. Vehicles equipped with this technology consume considerably less fuel, especially in urban traffic, and thereby emit less CO2.
Start/stop systems switch off the engine if the vehicle is stationary – for example in traffic jams or at red traffic lights. Depending on the vehicle, start/stop systems save up to five per cent fuel in the New European Driving Cycle (NEDC) and produce correspondingly less CO2. In the urban part of the NEDC, the reduction in consumption and emissions can be as much as eight per cent. Bosch has considerably increased the specified number of engine starts of the start/stop starter and – as a consequence – increased its service life compared with a conventional starter. The more powerful electric starter motor features enhanced engagement components guarantee safe, fast, and quiet operation and increased engine starts. In addition to this extended functional range, the starter is compact and remains very easy to integrate in the vehicle. Unlike other technologies, this approach is also suitable for cold starts in diesel engines.
The start/stop systems from Bosch draw on the expertise of the company’s starter technology, drivetrain, and energy management fields. To this day, Bosch has sold more than 300 million conventional starters worldwide and as the system approach is based largely on existing components, an excellent cost-benefit ratio is a further argument in this Bosch technology’s favour. The system as a whole includes control software which can be integrated in the respective engine control unit, a crankshaft sensor with evaluation electronics, and a battery sensor. The battery sensor calculates the current battery charge level and relays this information to the system’s energy management. For reliable start/stop operation, Bosch also supplies alternators with a higher level of efficiency ensuring that the battery always has sufficient energy stored for start/stop operations