Current state-of-the-art series hybrid powertrains is to use the on-board generator (or fuel cell) as a range extender used to “charge the battery” usually at some pre-determined point of discharge thereby preventing full discharge of the battery/super-capacitor storage system. Modeling has shown this leads to oversized energy storage system components for a given criteria/performance. In the worst case, the current state-of-the-art provides a limp home facility also the state-of-discharge of the battery/super-capacitor can give varying vehicle performance depending on operational circumstances at the relevant time. That is the
operator can feel variance in electric vehicle performance from time-to-time.
A better architecture and management control is proposed. The Project is to realign the
genset, battery and super-capacitor in parallel onto the DC rail as a “multi-source” plug-in hybrid electric powertrain architecture with novel management control. The control technique, however, uses control algorithms based on rates-of-change of current and voltage rather than absolute values as is the case in most current systems and this technique is believed to be unique. Preliminary research/modeling shows that for a like-for-like overall performance the new system reduces genset size, battery and super-capacitor both electrically and dimensionally. Thereby reducing cost, weight and spatial requirements for all the key elements – a key strategic industry objective. Such saving will lead to lower costs and higher efficiency cars and other vehicles thus greatly assisting the low carbon economy.