1. Motors Applicable for Electric Hybrid Vehicle Presentation Brought To you By Sean Frost

2. Description of motors All motors are basically simple devices and depend on the attraction and repulsion of magnets for their operation. This simplicity may be deceiving, for motors have become highly sophisticated.

3. Factors to consider for proper motor application - Most practical to use single-phase or poly-phase motor with application - More poles the motor has, the more starting torque developed in a motor - Available system voltages and frequencies - Voltage spread that can be tolerated for each type of utilization equipment - Motor starting and operation on voltage levels in other parts of the system - Limitations placed on starting current - Pulsating driven-load requirements - Motor power factor and efficiency on system losses and operation - Changes in protective devices or interrupting equipment - Magnitude and duration of fault current contributed by the motor

4. Look at Speed Loads, Load Torque, Environment Table 3Load Characteristics of Vehicles Load DescriptionLoad Torques, % full load drvie torques HowAdjustable Break-Accel-PeakInertiaAmbientMountingEnvori-drivenspeed range, awayeratingrunningratio mentmax Vehicles, frieght200 50AWRDJL3 to 1 Vehicles, pass.10040020025AWDJRL10 to 1

5. Comparison of AC motors to DC motors Electric Current motor Comparison Table - 1 AC MotorDC Motor Single - Speed TransmissionMulti - Speed Transmission Light weightHeavier for same power Less ExpensiveMore Expensive 95 % efficient85-95% efficient Expensive/Complex controllerSimple controller Motor/Controller/Inverter More $Motor/Controller Less $ -Transformers only work on AC, which is one of the great advantages of AC. -DC power can be stored -DC is easier to control Power of a Motor P = nT n – speed of rotation [r/min] 9.55 P – mechanical power [W] T – Torque [N * M] 9.55 – a constant to take care of units[30/π] Efficiency of a machine η = Po η - efficiency Pi Po – Power out Pi – Power in X 100

6. MOTORS TO USE IN ELECTRIC VEHICLES: There are three broad classes of Motors that are usually used in electric vehicles: [1] Brushed DC motors - brushed series-wound DC motor is the best overall motor for affordable road-going [2] Brushless DC motors - require expensive controllers, are generally more expensive. [3] AC induction motors - AC motors operate at high rpm that have to be stepped down, and have expensive and complex speed control systems

7. Table 2 - Comparison of motor types Brushed DCAC InductionDC Brushless Power/Weight Ratio:FairFair-GoodExcellent Max Voltage:144Hi Volt. 460+ Cooling:None - must be addedVariety Air/Liquid/etc. High Torque Band:LimitedBroad Regeneration:UncommonYes -capable Max. Efficiency80-90%85-96%90-95% Max RPM:Low(~5000)High(8000+)High(~8000) Other advantages:Inexpensive, easy tostandard workhorseNo brushes, simple design control, adaptablelast foreververy efficient Other disadvantages:High Current, LowLimited Starting torqueNew Technology, limited Voltage operationcomparativelyavailability in our power Brushes create electrical range, require complex noise, eventually wear out drive electronics $ Typical Price Range: (including controller) $750.00 - $5000.00$1600.00 -$ 8000.00$15000.00- $25,000.00 Consideration was given to permanent magnet, shunt, series and compound varieties of Brushed DC motors; Brushless DC motors; and AC induction motors, with the latter determined to be the best option. The table below shows comparisons of typical motor specs by type.

8. Set on using a DC motor Permanent magnet motors are very efficient, but only in a very narrow rpm band, and quickly lose their efficiency in the varying speeds of normal driving. Shunt and compound motors are more expensive to build and have poorer acceleration than series motors. For these reasons, the brushed series DC motor is the motor of choice for this particular application.

9. Set on Using AC motor Figure 1 - Typical speed-torque characteristics for Design A, B, C, and D Induction motors -There are several of the advantages of induction motors: no brushes or commutator means easier manufacture, no wear, no sparks, no ozone production and none of the energy loss associated with them. -Industrial applications use three phase extensively, and the three phase induction motor is a standard workhorse for high power applications.

10. Recap on what we have just learned - Decide whether a DC or AC motor is more suitable for your application. There are advantages to using either or, so do not just disregard one type over another. - If using DC motor - use brushed series wound motor - If using AC motor – use 3 phase AC Induction motor