Consider an e-bike is designed according to EN 15194 standard (pedal assisted and all electric driving modes with the maximum 250W rated output power and electric motor assist is cut-off at 25km/h). Assume the mass of the bicycle is 24 kg (including electric motor and battery) and the mass of rider is 75 kg. The rolling resistance coefficient of bike tyres is 0.007. The bike is using a direct drive brushless DC motor (hub motor) mounted in 29 inch-rear wheel (see below figure). a. Assuming the maximum output power is confined at 250W by the motor driver, find the maximum road grade angle that the bike can climb at 10 km/h. b. Assuming the battery voltage is 48V, calculate the energy capacity of the battery for two-hour all-electric driving on flat road with 250W motor power (assume the motor-driver overall efficiency is 90%)

Consider an e-bike is designed according to EN 15194 standard (pedal assisted and all electric driving modes with the maximum 250W rated output power and electric motor assist is cut-off at 25km/h). Assume the mass of the bicycle is 24 kg (including electric motor and battery) and the mass of rider is 75 kg. The rolling resistance coefficient of bike tyres is 0.007. The bike is using a direct drive brushless DC motor (hub motor) mounted in 29 inch-rear wheel (see below figure). a. Assuming the maximum output power is confined at 250W by the motor driver, find the maximum road grade angle that the bike can climb at 10 km/h. b. Assuming the battery voltage is 48V, calculate the energy capacity of the battery for two-hour all-electric driving on flat road with 250W motor power (assume the motor-driver overall efficiency is 90%)

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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A DC series motor takes the current of 15A and terminal voltage is 220 V. The armature and field resistance is 2 ohms and 0.2 ohm respectively. If the field resistance is shunted by resistance which is same as field resistance value and current taken by motor is 12 A then back emf induced is (estimated time 2 minutes) a.194.8V b.198.4 V c.217.6 V d.200.3 V
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The choice of motor used for high power level applications is ................
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