The Coil Span Factor, also known as the Pitch Factor or Chording Factor, is a way to measure how much the distance between the two sides of a coil deviates from a full-pitch value. It is defined as the ratio of the voltage generated by a short-pitch coil to the voltage generated by a full-pitch coil.
The full-pitch value is 180 degrees, which is the distance between the central lines of two poles of the alternator. If the coil span is exactly equal to this distance, it is considered a full-pitch coil. However, if the coil span is shorter than 180 degrees, it is considered a short-pitch coil.
The Coil Span Factor is a number between 0 and 1, where 1 means that the coil span is equal to a full-pitch value and 0 means that the coil span is very short.
In simple terms, the Coil Span Factor compares the amount of voltage generated by a short-pitch coil to the amount of voltage generated by a full-pitch coil. It is a way to measure how different the coil span is from the full-pitch value.
When the span of the coil is reduced, the coil span will be (180 - alpha) electrical degrees. In simple words, the coil span factor or pitch factor in an alternator refers to the distance between two sides of a coil and how it relates to the distance between the poles of the alternator. A full-pitch coil will have a span equal to the distance between the poles, while a short-pitch coil will have a smaller span. This can affect the voltage generated in the coil, with full-pitch coils having voltages that are in phase with the coil-side voltages.
The coil span-factor or pitch factor is a measure of how much the coil span deviates from the full-pitch value of 180 degrees. It is defined as the ratio of the voltage generated in a short-pitch coil to the voltage generated in a full-pitch coil. In other words, it compares the amount of voltage produced by a coil with a smaller span to the amount of voltage produced by a coil with a full span.
The use of short-pitch coils can affect the overall performance of the alternator, as the voltage generated in a short-pitch coil will be less than the voltage generated in a full-pitch coil. However, it may be useful in certain situations, such as reducing the size and weight of the alternator or allowing for more efficient use of the available space within the alternator.
Advantages of Short Pitch Coil or Chording:
Short pitch coils, also known as chorded coils, have a few advantages over full-pitch coils.
- One of the main advantages is that they save on the material used for the conductor, or the wire that makes up the coil. Because the coil span is shorter, the ends of the winding are also shorter, which means less material is needed to make the coil.
- Another advantage is that short pitch coils can help improve the waveform of the voltage generated by the alternator. In an alternator, the voltage generated by the coils can be distorted by harmonics, which are extra frequencies that are not the main frequency of the alternator. These harmonics can cause the waveform of the voltage to become more complex and less like a sine wave.
- By using short pitch coils, the effects of these harmonics are reduced, and the waveform of the voltage becomes more like a sine wave. This can be beneficial for the devices that use the power generated by the alternator as a sine wave is considered a cleaner form of energy.