In the 1890s, electric bicycles were documented within various U.S. patents. For example, on 31 December 1895, Ogden Bolton Jr. was granted U.S. Patent 552,271 for a battery-powered bicycle with "6-pole brush-and-commutator direct current (DC) hub motor mounted in the rear wheel". There were no gears and the motor could draw up to 100 amperes (A) from a 10-volt battery.
Controllers for brushless motors: E-bikes require high initial torque and therefore models that use brushless motors typically have Hall sensor commutation for speed and angle measurement. An electronic controller provides assistance as a function of the sensor inputs, the vehicle speed and the required force. The controllers generally allow input by means of potentiometer or Hall Effect twist grip (or thumb-operated lever throttle), closed-loop speed control for precise speed regulation, protection logic for over-voltage, over-current and thermal protection. Bikes with a pedal assist function typically have a disc on the crank shaft featuring a ring of magnets coupled with a Hall sensor giving rise to a series of pulses, the frequency of which is proportional to pedaling speed. The controller uses pulse width modulation to regulate the power to the motor. Sometimes support is provided for regenerative braking but infrequent braking and the low mass of bicycles limits recovered energy. An implementation is described in an application note for a 200 W, 24 V Brushless DC (BLDC) motor.
With over a decade of experience as an advertising executive, Mark is certain that the market will accept the electric bike and is here to make sure it happens. Mark has an impressive list of former clients in industries like pharmaceuticals, convenience stores, community banks, floor coverings, visitors’ bureaus, resorts and Location Based Services (LBS). When he’s not on Facebook, tweeting or learning how to leverage the latest viral marketing techniques,...
Powered by a 250-watt Brose Centerdrive system, the Redux is capable of reaching speeds of up to 28 mph, which comes in handy when dodging traffic. Its 36-volt lithium-ion battery provides enough juice to give the bike a range of up to 80 miles between recharges, making it a great option for daily commuters. Raleigh even outfitted the bike with wide tires which provide stability and traction, even when the road gets wet. Other key features include a 10-speed Shimano crankset and shifters and a built-in LCD screen that displays all the usual information.
After you decide which style of e-bike you want, consider the class. In the US, there are three classes defined by the type of assist and how fast the motor will propel you. Most electric bikes sold are class 1 or 3. Class 1 bikes have a motor (max 750w) that assists while you're pedaling, up to 20 mph. Class 3, also known as “speed pedelec” can also have up to a 750w motor, but it can assist you up to 28mph. Both of those are allowed in most states and cities without license. Class 2 have throttles that don't require you to pedal to get a boost. They're allowed on most streets, bike lanes, and paths, but less popular than the other classes and not covered much here (because we still love to pedal and the greater distances pedal assist bikes can cover).