Electric vehicle
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| Table 8.4 Simple fuel cell simulation results, showing great improvement in range over a battery vehicle Simulation, SFUDS driving Range (km) cycle in both cases GM EV1 with standard lead acid batteries, good conditions 148 GM EV1 with a fuel cell and cryogenic H 2 store 485 Derived in Appendix 2 of Larminie and Dicks (2003). Electric Vehicle Modelling 215 8.4.6 Range Modelling of Hybrid Electric Vehicles All the modelling we have done so far has involved equations which the system followed in a more or less predetermined way. However, when we come to a hybrid electric vehicle, then this is no longer so. Hybrid electric vehicles involve a controller, which monitors the various power in the system and the state of charge of the battery, and makes decisions about the power to be drawn from the engine, battery, and soon. Very little about the energy flow is inevitable and driven by fixed equations. Furthermore, the strategy will change with time, depending on issues such as when the vehicle was last used, the temperature, the need to equalise the charge in the batteries from time to time, and a host of other criteria. The decision making of these controllers is not at all simple to simulate. Another complication is that there are so many different configurations of hybrid electric vehicles. The result is that the simulation of these vehicles cannot be attempted or explained in a few pages of a book like this. Indeed, the use of a simple program such as MATLAB® on its own is probably not advisable. At the very least the Simulink extension to MATLAB® should be used. There area number of vehicle simulation programs available or described in the literature, for example Bolognesi et al. (2001). Among the most well known of these is ADVISOR (Wipke et al., 1999), which is MATLAB® based. The program for the energy controller in a hybrid system, which is a subsystem of vital importance, will often be written in a high-level language such as C. It makes sense to incorporate the simulator in the same language, and then it should be possible to use the very same control program that is being written for the controller in the simulation. This has obvious reliability and efficiency benefits. Download 3.49 Mb. Share with your friends:
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