I recall listening to the owner of the last car dealer I worked for explaining regenerative braking in electric and hybrid vehicles beautifully wrong. And I was sure I knew better.
Well, his explanation, which included the brakes themselves, is still wrong. But I’ve had it wrong too!
I was sure that I’d been taught that the electric motor went into reverse when the accelerator pedal is released. It doesn’t! What actually happens is far more complicated, and its possible that the motor reversal concept was taught for its simplicity.
So here is a simplified but correct explanation. An EV motor is a coil of wire wrapped around some magnets. When current is applied, the electromagnetic force spins the magnets. A generator is a coil of wire wrapped around some magnets. When torque is applied to the magnets, electricity is generated in the coil.
Releasing the accelerator removes the current from the electric motor and applies torque to it, which comes from the still turning wheels. The motor is now a generator returning charge to the battery.
The generation of electricity in this way creates the resistive force that brakes or slows the car.
The use of the word brakes adds confusion to the driving public. The actual brake pads and rotors are not involved.
And we discovered more on that too. Check in tomorrow…
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The material on these pages is provided for information sharing purposes only, and should not be used in lieu of an OEM service manual or factory authorized service procedure. We are not in the auto repair business nor do we publish automotive service manuals. Nothing we include on these pages and posts has been reviewed, approved or authorized by any vehicle manufacturer.
Remember that only proper service and repair procedures will ensure the safe and reliable operation of your car. In addition, proper safety procedures and precautions, such as the use of safety goggles, the right tools and the equipment should be followed at all times to eliminate the possibility of personal injury or improper service which could damage the vehicle or compromise its safety.
Technology is always changing and what is current and accurate today may be literally out-of-date and inaccurate tomorrow. And when it comes to the current state of flux in the auto industry, nothing is more true.
The author has 30+ years of automotive experience and has assembled the most extensive collection of symbols and warning lights anywhere (over 1,000!) and can help you open and start any keyless start car with a dead key fob battery. BA, St. Joseph’s, ME: MS, RPI, NY
So I got regenerative braking wrong
I recall listening to the owner of the last car dealer I worked for explaining regenerative braking in electric and hybrid vehicles beautifully wrong. And I was sure I knew better.
Well, his explanation, which included the brakes themselves, is still wrong. But I’ve had it wrong too!
I was sure that I’d been taught that the electric motor went into reverse when the accelerator pedal is released. It doesn’t! What actually happens is far more complicated, and its possible that the motor reversal concept was taught for its simplicity.
So here is a simplified but correct explanation. An EV motor is a coil of wire wrapped around some magnets. When current is applied, the electromagnetic force spins the magnets. A generator is a coil of wire wrapped around some magnets. When torque is applied to the magnets, electricity is generated in the coil.
Releasing the accelerator removes the current from the electric motor and applies torque to it, which comes from the still turning wheels. The motor is now a generator returning charge to the battery.
The generation of electricity in this way creates the resistive force that brakes or slows the car.
The use of the word brakes adds confusion to the driving public. The actual brake pads and rotors are not involved.
And we discovered more on that too. Check in tomorrow…
——————————————————————-
The material on these pages is provided for information sharing purposes only, and should not be used in lieu of an OEM service manual or factory authorized service procedure. We are not in the auto repair business nor do we publish automotive service manuals. Nothing we include on these pages and posts has been reviewed, approved or authorized by any vehicle manufacturer.
Remember that only proper service and repair procedures will ensure the safe and reliable operation of your car. In addition, proper safety procedures and precautions, such as the use of safety goggles, the right tools and the equipment should be followed at all times to eliminate the possibility of personal injury or improper service which could damage the vehicle or compromise its safety.
Technology is always changing and what is current and accurate today may be literally out-of-date and inaccurate tomorrow. And when it comes to the current state of flux in the auto industry, nothing is more true.
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The author has 30+ years of automotive experience and has assembled the most extensive collection of symbols and warning lights anywhere (over 1,000!) and can help you open and start any keyless start car with a dead key fob battery. BA, St. Joseph’s, ME: MS, RPI, NY