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Electric Motors as Automotive Prime Movers. P M V Subbarao Professor Mechanical Engineering Department. Eliminate Digestion System in an Artificial Horse to Mimic a Horse…. 21 st Century Busy Roads. Vehicle speed and acceleration/deceleration in an FTP urban drive cycle.
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Electric Motors as Automotive Prime Movers P M V Subbarao Professor Mechanical Engineering Department Eliminate Digestion System in an Artificial Horse to Mimic a Horse…
Vehicle speed and acceleration/deceleration in an FTP urban drive cycle
Energy Loss : Urban Driving : 3000 CC Engine Vehicle Standby 8% Aero 3% Fuel Tank 100% 16% 13% Engine Driveline Rolling 4% Braking 6% Driveline Losses 3% Engine Loss 76% POWERTRAIN VEHICLE-Related
Energy Loss : Highway Driving : 300 CC Engine Vehicle Standby 0% Aero 10% Fuel Tank: 100% 23% 19% Engine Driveline Rolling 7% Braking 2% Driveline Losses 4% Engine Loss 77% POWERTRAIN VEHICLE-Related
Battery Fuel Motor/Generator Engine Transmission Transmission Low Irreversibility Prime Movers Combustion Engines Battery Electric
Energy Loss : City Driving – Electric Vehicle Aero 29% Batteries 100% 90% 76% Motor Driveline Rolling 35% Braking 11% Driveline Losses 14% Motor Loss 10% POWERTRAIN VEHICLE-Related
Mine to Wheel Efficiency Mine-to-Tank Tank-to-Wheels 31% 23% Generation 33% Transmission 94% Plug-to-Wheels 76% 31% 76% = 23% Refining 82% Transmission 98% Pump-to-Wheels 16% 13% 80% 80% 16% = 13%
Another Major Suitability Characteristic of Resource to Vehicle
Characteristics of A Typical variable-speed electric motor The range of the constant power operation depends primarily on the particular motor type and its control strategy.
Speed Ratio of Typical variable-speed electric motor • At the low-speed region the motor has a constant torque. • The maximum speed at which a motor generates a constant (maximum) torque is known as base speed. • In the high-speed region the motor has a constant (maximum) power. • The highest speed at which the motor generates constant maximum power is known as maximum speed. This characteristic is usually represented by a speed ratio x, defined as the ratio of its maximum speed to its base speed.
Speed ratio & Speed–torque profile of a 60 kW electric motor
Tractive effort and power versus vehicle speed with different Motors
Electric Vehicles for the 21st Century Tesla Motors is a Silicon Valley automobile startup company, which unveiled the 185 kW Tesla Roadster on July 20, 2006. As of March 2008, Tesla has begun regular production of the Roadster. Peak torque begins at 0 rpm and stays powerful at 13,000 rpm. This makes the Tesla Roadster six times as efficient as the best sports cars while producing one-tenth of the pollution with a range of 220 miles.
eBox The eBox is the purest and greatest example of building your own electric vehicle using an existing vehicle platform. This urban utility vehicle, shown in Figure, has a range of 120–150 miles, 0–60 mph in 7.5 seconds with a top speed of 95 mph. It has a 30-minute charge for 20–50 miles and a full charge in two hours. It has regenerative braking, lithium-ion batteries, and all the bells and whistles of a regular internal combustion engine vehicle.
Battery Technologies • The viable EV batteries consist of • the lead-acid battery, • nickel based batteries such as nickel/iron, nickel/cadmium, and nickel–metal hydride batteries, and • lithium-based batteries such as lithium polymer and lithium-ion batteries. • The energy or power losses during battery discharging and charging appear in the form of voltage loss. • Thus, the efficiency of the battery during discharging and charging can be defined at any operating point as the ratio of the cell operating voltage to the thermodynamic voltage.
Energy Efficiency of A battery The efficiency of the battery during discharging: The efficiency of the battery during charging:
Energy and Power Needs • Rate is a problem. • Example: refill a gas tank with 15 gal in 5 min. • The energy rate is roughly that of 20 major campus buildings! • It is costly and problematic to fill batteries quickly.