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To reduce the number of traffic accidents, most of the governments have mandated to include Combi Brake System (CBS) or Anti-lock Braking System (ABS) in two wheelers. While most of the homologation requirements for CBS can be fulfilled by straight line motion, CBS behavior is crucial while cornering for safety aspects. When vehicle is in cornering motion, the lateral forces generated at the tire decreases the effective longitudinal force available, which implies lesser braking force at tire. This paper represents a design methodology for tuning CBS for various critical scenarios mainly during cornering maneuver. A detailed study has been made at various combination of vehicle lean angle, vehicle speed and friction coefficient of road (μ) in straight line and cornering maneuver to effectively decide on front to rear brake force distribution to avoid either of the tires’ lock-up.

Reducing the number of traffic accidents is a declared target of most governments leading to mandating Combined Braking System (CBS) or Anti-lock Braking System (ABS) in two wheelers. Traditional friction braking torque and motor braking torque can be used in braking for electric 2wheeler. Use of CBS and ABS helps in active control of vehicle braking leading to better deceleration, prevention of tire locking, control on vehicle pitch etc. A braking model (friction braking + motor regenerative braking) along with battery dynamics is developed in Matlab/Simulink and validated with real vehicle response. This paper presents an analysis on vehicle braking separately for heavy and mild braking in various vehicle load conditions. During heavy braking a feedback control algorithm is used to maintain optimal slip ratio both at the front and rear tire, active control on CBS and ABS+Regen is done and performance is compared.

Various current control algorithms are presented in this paper to prevent vehicle cut-off and increase the range of an electric 2 wheeler based on SoC, battery temperature and motor temperature. At lower SoCs if the current demand is very high there is a possibility of cell voltage hitting the lower threshold voltage leading to cut-off. An algorithm is proposed where current (maximum allowed) derating is done based on reducing SoC, battery voltage and real time throttle demand. Lithium ion cells operating temperature has an upper cap. Rate of increase of battery temperature mainly depends on current demand by motor while the initial battery temperature also depends on ambient temperature. To prevent the battery temperature from reaching the upper threshold a battery temperature based current (maximum allowed) derating algorithm is used. As one algorithm affects the other, this leads to Multi Input Single Output (MISO) system configuration.

In this paper, an optimization method is proposed to improve the efficiency of a transmission equipped electric vehicle (EV) by optimizing gear shift strategy. The idea behind using a transmission for EV is to downsize the motor size and decrease overall energy consumption. The efficiency of an electric motor varies with its operating region (speed/torque) and this plays a crucial role in deciding overall energy consumption of EVs. A lot of work has been done to optimize gear shift strategy of internal combustion engines (ICE) based automatic transmission (AT), and automatic-manual transmissions (AMT), but for EVs this is still a new area. In case of EVs, we have an advantage of regeneration which makes it different from the ICE based vehicles. In order to maximize the efficiency, a heuristic search based algorithm - Genetic Algorithm (GA) is used.