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Electric motor

The engine is one of the most important parts ofe-vehicles and together with the battery, the driving force for good support. Each engine has its own characteristics and influences the driving behavior of the vehicle. 

Whenever something turns or moves at the push of a button, electric motors are usually at work. However, only very few people are aware of this when using it. Even if they bring toothbrushes, coffee machines or countless other devices and machines to life every day with the click of a button. Electric motors often work hidden, quietly and inconspicuously for years. Only in recent years have electric motors increasingly become the focus of general interest - especially in connection with e-mobility.  

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What is an electric motor?

Simply put, an electric motor is an electromechanical converter that produces mechanical power from electrical power. As a result, electric motors have a power connection to which the electrical energy is supplied. To do this, it uses the attractive and repulsive forces that magnetic fields exert on each other. An electric motor usually consists of a fixed stand, the so-called stator, and an inner part that rotates within it, the rotor. Both parts have current-carrying coils, each of which generates a magnetic field. The alignment of the magnetic fields that alternately repel and attract each other (north pole/south pole) depends on the direction of the current. Electric motors can be used in a much wider speed range than internal combustion engines. The maximum torque is already available from a standstill - so the impressive pulling power is fully available from the start. For this reason, electric drive models do not require a clutch or manual transmission. As a rule, however, an efficient reduction gear with a fixed ratio (only one gear) is used. 

By reversing the polarity of the coils several times during one revolution of the rotor, its continuous rotation is achieved. The rotating movement is used to drive the wheels in a car: it drives electrically. The mechanical output, which in the simplest case is designed as a shaft, rotates and serves as a drive for machines and devices. The functional principle of an electric motor is based on the magnetic effect of the electric current. 

An electric motor takes advantage of the fact that magnets influence each other depending on how they are aligned with each other. Like magnetic poles repel each other and unlike magnetic poles attract each other. 

Types of electric motors – what are there?

There are now many different types of electric motors. The most important difference between the individual types is the power supply. It is determined during the design whether the engine will be includedSamehstrom,Alternating current or must be powered by three-phase current. 

But the required magnetic fields are also generated in different ways for each motor. In addition to strong permanent magnets, electromagnets are also used depending on the intended use. In the simplest case, a coil of copper wire is wound over an iron core made of sheet metal plates to generate the required magnetic field. 

When using permanent magnets, this is called a permanent magnet motor. The main advantage of a permanent synchronous motor is that there are virtually no losses in the rotor because, in contrast to asynchronous machines, no currents flow in the rotor. The reluctance motor, on the other hand, works with the attractive force of magnets on iron, as is known from kitchen magnets, for example.

Permanent magnet motors are used in particular where a high power-to-weight ratio is required and where only limited installation space is available. Mention should be made here of the automotive industry, electric motors, turbo runners and where particularly high efficiency is important, which the permanent magnet motor offers.

Basically, here is betweene-car-Motors and the engines for e-two-wheelers such asScooter,Scooters orPedelecs. In the following article we will introduce you to the most popular types of engines and their special features. 

e-motors for two-wheelers

Hub motor 

One of the best-known motors for electric two-wheelers is the hub motor. This is installed as a drive unit directly in the center of the drive wheel. Although technically this does not necessarily have to be an electric motor, electric motors are the typical design for wheel hub motors. On two-wheelers, the electric motor can be used in both the front and rear wheels. If the electric motor is located directly on the pedals instead, it is called a bottom bracket motor. Both variants have advantages and disadvantages and are widespread in two-wheeled electromobility. 

Wheel hub motors offer two significant advantages over bottom bracket motors. On the one hand, they do not put any additional strain on your drive chain or drive belt. On the other hand, a front wheel motor can also be retrofitted relatively easily to a conventional bicycle. However, the additional weight on the front wheel interferes with steerability, especially on sandy or loose surfaces. The response behavior of bottom bracket motors is also better. 

Bottom bracket motor 

The bottom bracket motor (also called mid-motor) is often usede-bikes used. It is located below the seat post near the bottom bracket. The low placement gives a Pedelec a low center of gravity and guarantees comfortable and easy driving. Hub motors, on the other hand, can impair steering behavior or cause the vehicle to slip due to the higher weight of the tires. Bottom bracket motors are permanently installed in the frame and are particularly suitable for off-road vehicles. But the all-rounder among e-bike drives can also be used well in the city and in the flat countryside. 


At ae-scooter The two most common motor variants are the wheel hub motor and  Mid-engine with chain or belt drive. 

Wheel hub motors are typically located in the rear wheel and deliver their power directly to the wheel without going through the chain (or a belt drive). A mid-engine, on the other hand, sits in the frame and transmits its power to the rear wheel via a chain or belt. 

A wheel hub motor is usually significantly quieter when driving.  The running noise of the chain or belt on mid-engines is so audible on some models that it is difficult to distinguish them from (quieter) scooters or small motorcycles with combustion engines when driving past. Experience has shown that comparable electric scooters with hub motors are sportier and slightly better, despite identical engine performance Acceleration values, as models with chain or belt drive. 

e-bike motors

If you are thinking about getting a bike with an electric motor, be sure to take a test ride first to familiarize yourself with the riding characteristics. Ate bike Motors are mainly differentiated between different positions of the motor: The motor can be mounted at the front, in the middle or at the back. eBikes with a mid-engine drive are one of the most popular and common types. The pedals have to be pedaled at a certain frequency so that the motor also helps. The pedal support therefore depends on thison how hard you kick. This often means that the bike has to be at least 12 km/h or faster, even in the lowest gear, so that the motor purrs smoothly. This is not a problem on straight stretches and gentle inclines, but on steeper hills and driveways, muscle and motor power are no longer sufficient to reach or maintain 12 km/h. In order for the engine to provide full power even in the low speed range, it actually has to have an e-Be a mountain bike. 


When we talk about an e-bike with a mid-engine, this means that the motor is located at the bottom bracket. As a result, the bike's center of gravity is low and central. An e-bike with a mid-engine therefore has ideal weight distribution, which leads to greater stability. One of the biggest advantages is that this motor does not drive the wheel, but rather the pedals. Ultimately, pedal assistance depends on how hard you pedal. This optimizes pedaling and ensures a comfortable riding experience. Since mid-engine e-bikes offer high performance thanks to their power, they are ideal for demanding bike tours. 

Rear engine

One of the biggest advantages of a rear engine is the feeling of powerful thrust in the back. The riding experience on a rear-engined e-bike usually feels surprisingly familiar. This is because the drivetrain of a “traditional” bike is also located on the rear wheel. 

E-bikes with a rear motor are often equipped with derailleur gears. This creates more leeway in the gears, which has a positive effect on the driving experience, especially on hilly terrain. Since the engine is directly connected to the rear wheel, the result is a very fast but above all sporty driving experience. 

Advantages of the rear engine:

  • Natural driving experience: support depending on your own effort 

  • Ideal for long distances and leisure use thanks to the sporty derailleur gears.

  • Speeds up to 45 km/h possible 

  • Silent and powerful motor 


Disadvantages of the rear engine: 

  • More maintenance through derailleur gears 

  • Cannot be combined with hub gears 

  • The rear of the bike weighs more, making it difficult to transport manually 

Front engine

An e-bike with a front motor is usually cheaper than an e-bike with a mid or rear motor. In addition, this engine can be combined with all switching systems. A big advantage of the front engine is that it provides support when starting off, regardless of the gear selected. A front engine requires less maintenance than other engines. In addition, the motor weighs less, making it easier to cycle without assistance. 

Advantages of the front engine: 

  • Cheaper 

  • Can be combined with all switching systems 

  • Low maintenance

  • Lighter than other engines 

  • Ideal for flat terrain 

  • Most energy efficient 

Disadvantages of the front engine: 

  • Higher risk of slipping

  • Less powerful support 

  • Most of the weight is on the front of the bike 

  • Not suitable for mountain areas 

  • Less natural driving experience 

e-motors for cars

There are three types of electric motors, which are hybrid orPlug-in electric vehicle can be used. 


Ppermanent magnet synchronous machine 

Internal permanent magnet motors or IPM motors (also: permanent magnet synchronous machine) have a high power density and an hOhen efficiency over their operating range. Almost all hybrid and plug-in electric vehicles use permanent magnets in their drive motors. Due to high costs for magnets (NeFeB and SmCo) and rotor manufacturing, these motors are relatively expensive. Additional challenges when using IPM motors include the limited availability and high cost of magnetic materials. IPM motors are the future of electric vehicles in the next decade. Modern electric cars today have synchronous or asynchronous motors on board. The difference lies in how the rotor works: With a synchronous motor, it simultaneously follows the magnetic rotating field of the stator - i.e. synchronously. With an asynchronous motor, on the other hand, it follows the stator with a time delay, therefore asynchronous.  

induction motor

Induction motors (asynchronous motors) have a highTorque and offer high reliability. However, their power density and overall efficiency are lower than IPM motors. They are also available in various industries today, including in some production vehicles, such as the Tesla S with an asynchronous engine. In drive motors, the rotor is a short-circuited squirrel cage rotor. Because this engine technology is mature, it is unlikely that research will be able to achieve additional improvements in terms of efficiency, cost, weight and volume. 

reluctance motor

Switched reluctance motors offer a more cost-effective option. They have a robust structure that can withstand high temperatures and speeds. However, they generate more noise and vibration than comparable engine designs, which poses a major challenge for use in vehicles. Switched reluctance motors are also less efficient than other types of motors and the overall cost of the electric drive system increases. However, the future of e-mobility could belong to compact reluctance motors, as they do not have anyRare Earth need. 

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