Tesla cars
Figure 2: AC current graph
Figure 2 shows the difference between the two halves of a complete AC current cycle which explains why each pole switches every half cycle.
Figure 1 also shows the rotor. This is like the stator except it is designed to rotate. Like the stator, the rotor also consists of several electromagnets which are arranged around a cylinder and sit wholly inside the stator. The rotating magnetic field in the stator can then induce a magnetic field into the rotor which causes it to rotate every half cycle of alternating current. What makes
this so great at accelerating is that its speed is directly proportional to the frequency of the AC power supply. It allows the motor to reach 18000 rpm in the Tesla Model S (Lesics, 2018). The issue with an internal combustion engine in comparison to the induction motor is that it can only provide useful torque and power output within a limited speed range, stopping it from reaching 18000 rpm.
Figure 3: 4-stroke cycle engine (Stevens, 2021)
This is because in an internal combustion engine, to produce torque, the ignition and combustion of fuels (like petrol) cause only a linear movement of a piston up and down as shown in figure 3. What this means is that the linear motion of the piston must be converted into rotational motion in something called the crankshaft to provide useful torque. Unfortunately, this causes a few issues which need solving. Lesics (Lesics, 2018) claims
that some of these are that the internal combustion is not self-started, the power output is uneven as well as that the crankshaft needs to be balanced due to the huge forces that are exerted on it from the piston. Therefore, many accessories are required to solve these problems. For instance, to balance the crankshaft, there must be counterweights which balance these forces, preventing damage to the components. Overall, this results in the induction motor being more reliable.
Development of the battery pack
The next thing that makes Tesla cars so advanced are the batteries which enable them to travel much longer distances per charge than their competitors. For example, a popular electric car, called the Porsche Taycan, can travel 300 miles per charge ( Porsche Taycan review - Range, charging and running costs. n.d.). The Tesla model S, however, can travel as much as 402 miles on a single charge (Burns, 2020). Many other electric car models often struggle to even break 250 miles. For example, the Ford Mustang Mach-E can achieve between 248- 273 miles per charge, emphasizing Tesla’s superiority in battery technology ( Ford Mustang - Mach-E. n.d.).
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