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  2. Motor constants - Wikipedia

    en.wikipedia.org/wiki/Motor_constants

    Motor velocity constant, back EMF constant. is the motor velocity, or motor speed, [2] constant (not to be confused with kV, the symbol for kilovolt), measured in revolutions per minute (RPM) per volt or radians per volt second, rad/V·s: [3] The rating of a brushless motor is the ratio of the motor's unloaded rotational speed (measured in RPM ...

  3. Duty cycle - Wikipedia

    en.wikipedia.org/wiki/Duty_cycle

    Duty cycle. A duty cycle or power cycle is the fraction of one period in which a signal or system is active. [1][2][3] Duty cycle is commonly expressed as a percentage or a ratio. A period is the time it takes for a signal to complete an on-and-off cycle. As a formula, a duty cycle (%) may be expressed as: Equally, a duty cycle (ratio) may be ...

  4. Time constant - Wikipedia

    en.wikipedia.org/wiki/Time_constant

    Time constant. In physics and engineering, the time constant, usually denoted by the Greek letter τ (tau), is the parameter characterizing the response to a step input of a first-order, linear time-invariant (LTI) system. [1][note 1] The time constant is the main characteristic unit of a first-order LTI system. It gives speed of the response.

  5. Energy efficiency in transport - Wikipedia

    en.wikipedia.org/wiki/Energy_efficiency_in_transport

    The General Motors EV1 was rated in a test with a charging efficiency of 373 Wh-AC/mile or 23 kWh/100 km [67] approximately equivalent to 2.6 L/100 km (110 mpg ‑imp; 90 mpg ‑US) for petroleum-fuelled vehicles. Chevrolet Volt in full electric mode uses 36 kilowatt-hours per 100 miles (810 kJ/km; 94 mpg‑e), meaning it may approach or exceed ...

  6. Power-to-weight ratio - Wikipedia

    en.wikipedia.org/wiki/Power-to-weight_ratio

    Power-to-weight ratio is a measurement of actual performance of any engine or power source. It is also used as a measurement of performance of a vehicle as a whole, with the engine's power output being divided by the weight (or mass) of the vehicle, to give a metric that is independent of the vehicle's size. Power-to-weight is often quoted by ...

  7. Driving cycle - Wikipedia

    en.wikipedia.org/wiki/Driving_cycle

    Driving Cycle Design. The "Drive-cycle" basically is the representative of the road. Drive cycles are used to reduce the expense of on road tests, time of test and fatigue of the test engineer. The whole idea is to bring the road to the test lab (a chassis dynamo-meter) or to the computer simulation. Two kinds of drive cycle can be made.

  8. Drift velocity - Wikipedia

    en.wikipedia.org/wiki/Drift_velocity

    The formula for evaluating the drift velocity of charge carriers in a material of constant cross-sectional area is given by: [1] u = j n q , {\displaystyle u={j \over nq},} where u is the drift velocity of electrons, j is the current density flowing through the material, n is the charge-carrier number density , and q is the charge on the charge ...

  9. Electric motor - Wikipedia

    en.wikipedia.org/wiki/Electric_motor

    An electric motor is a machine that converts electrical energy into mechanical energy. Most electric motors operate through the interaction between the motor's magnetic field and electric current in a wire winding to generate force in the form of torque applied on the motor's shaft. An electric generator is mechanically identical to an electric ...