Smart Braking System
What is smart braking?
The concept of smart braking System is to regenerate power using the mechanical structure and minimize losses. When a car brakes, the brake pads rub against the wheel. The frictional force is produced to stop the forward momentum and heat results. This heat had 30% energy wasted. However, regenerative braking can utilize this heat energy. Electric motors and generators use magnetic fields and coiled wires. So, when a hybrid car reverses, it utilizes this concept to become an electric generator or dynamo. Thus, electricity transfers to the battery. But some energy will go to waste due to road friction or other factors.
How does the motor work as a generator?
The electric motors that drive the car can also work as a generator when using regenerative braking. In 1967, the regenerating brake was developed for the AMC Amitron. The car recharged using this brake
and was fully electric powered by a battery. Toyota Prius, Honda Insight, and other hybrids use the same concept. However, there are a few limitations. These include backup friction brake needed, at lower speed regeneration drops, etc. It is why controlling regenerative braking is vital to match friction for desired total braking effect. It is the GM EV-1 car to use it.
Electric Railway Operation
The traction motor connections are altered during braking to turn them into electrical generators. Also, the motor fields connect to the main traction generator (MG). And the motor armatures connect to the load. The rolling locomotive or multiple unit wheels turn the motor armatures. Therefore, motors act as generators. There is also less wear on friction braking components. There is less wear on brake parts caused by friction. The Delhi Metro saved around 90,000 tons of carbon dioxide (CO2) from being released into the atmosphere. All by regenerating 112,500-megawatt hours of electricity through regenerative braking systems between 2004 and 2007.
Dynamic and Regenerative Brakes
Unlike regenerative brakes, dynamic brakes dissipate electric energy as heat by sending the current via massive banks of variable resistors. Forklifts, Diesel-electric locomotives, and streetcars are examples of vehicles that utilize dynamic brakes. This heat helps to warm the vehicle's interior if properly built. But there is a fundamental drawback of regenerative brakes over dynamic brakes. It is the requirement for matching the generated current with the supply characteristics. It necessitates close voltage control with a DC supply. Some mountain railways use 3-phase power supplies and 3-phase induction motors. Thus, the trains have a constant speed.
Conclusion
Physicist Richard Feynman in the 1950s introduced the concept of transferring the vehicle’s kinetic energy using Flywheel energy storage. And is exemplified in complex high-end systems such as the
Zytek, Flybrid, Torotrak, and Xtrac are used in Formula One. Motorsports and motorcycles use it. Historically, it is for carmakers BMW and Honda tested it. The Bosch Group offers auto parts for electric
hybrid systems. So, what is the basic operational requirement for regenerative brakes? You need voltage current and magnetic field. Thus, wearing or mating of opposing surfaces (burnishing), torque, over-excitation, clutch wear, backlash, DC motor, and a dynamo.
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