The Power/Propulsion system encapsulates all of the electronics on the plane. It is important to know how this system works because it utilizes the electronics components to generate thrust and power the plane.
Electronics Overview
As a general overview, the electronics on the plane are powered by the flow of electrons (electricity). When it comes to electricity, there are three important aspects: voltage, current, and resistance. Let's briefly go over each.
Voltage, measured in volts (V), is the "pushing force" behind the electrons. When voltage is applied to a stream of electrons, it will cause the electrons to flow from the higher to lower voltage area. For example, electrons flow from the positive (5V, 12V, 24V, etc.) side of a battery to the negative end (0V).
Current, measured in amperes (amps), is the measure of the number of electrons moving through a given area per second (or more broadly, the net rate of flow of electrons through a given space). If we were to take a deeper look at current, we would find that electrons move incredibly fast. For instance, one coulomb (C) per second is equal to one amp. One coulomb is equal to 6.24x10¹⁸ electrons, so if there is one amp flowing through a wire, that means that there are 6.24x10¹⁸ electrons flowing through a single point every second!
Last, but certainly not least, resistance, measured in ohms (Ω), is exactly what it sounds like -- the opposition of current (essentially the "pulling force" behind the electrons). One way to think about resistance is the friction that acts on electrons as they flow through a circuit.
In summary, each aspect of electricity works together. In fact, they heavily influence each other. Here is a depiction:
In simpler terms, the relationship between them, known as Ohm's Law:
The batteries we are going to be using are Lithium-ion Polymer Batteries, otherwise known as LiPo batteries. The normal operating range of a LiPo battery is 3V to 4.2V. The more voltage the battery pack has, the more power it can supply to your vehicle. Overcharging and undercharging the battery will most likely result in irreparable damage. LiPo batteries are often deployed in products due to how effectively they can be used, drained, recharged, and used again for another battery cycle.
The typical number of cells in a LiPo battery ranges from 2 to 6 cells. This number could be as high as 20 although that is extremely rare. The discharge rating of a LiPo battery is measured in (c) and it measures the max it can supply for a set amount of time, and the maximum it can supply in general. Ampere hours refers to how much amperage one battery can supply to any product in the timeframe of 1 hour.
The connector typically used to charge batteries are the (still working)
It's fairly obvious how LiPo batteries are used, but how they are charged is a little more complicated. There is a system called Constant Charging Constant Voltage. When the charger is plugged in, it has to be made sure to distribute equal amounts of current to all the battery packs in the LiPo battery. Once the maximum amount of voltage in each pack is attained, the charger's only job is to gradually drop the current, so that the battery isn't getting overcharged, all while maintaining the maximum voltage levels in all the different packs. Making sure that each pack is discharging equal amounts of voltage while in use is extremely important. If the battery is discharging different amounts from different packs, the most likely result will be a fire. After fully charged, another process called balancing happens. What balancing does is make sure that every single cell in the battery is charged to the same level. This is also important due to the fact that if they are charged differently, they will inevitably discharge different amounts of voltage and inflict damage upon itself.
