How does a transformer work?
A transformer is an electrical device that takes electricity of one voltage and changes it into another voltage. You’ll see transformers at the top of utility poles and even changing the voltage in a toy train set. Basically, a transformer changes electricity from high to low voltage using two properties of electricity. In an electric circuit, there is magnetism around it. Second, whenever a magnetic field changes (by moving or by changing strength) a voltage is made. Voltage is the measure of the strength or amount of electrons flowing through a wire. (You may also want to read Chapter 7 on the Electrical transmission system in The Energy Story. If there’s another wire close to an electric current that is changing strength, the current of electricity will also flow into that other wire as the magnetism changes. A transformer takes in electricity at a higher voltage and lets it run through lots of coils wound around an iron core. Because the current is alternating, the magnetism in the
Asked by: Amal Dameer Answer A transformer is an electrical device used to convert AC power at a certain voltage level to AC power at a different voltage, but at the same frequency. The construction of a transformer includes a ferromagnetic core around which multiple coils, or windings, of wire are wrapped. The input line connects to the ‘primary’ coil, while the output lines connect to ‘secondary’ coils. The alternating current in the primary coil induces an alternating magnetic flux that ‘flows’ around the ferromagnetic core, changing direction during each electrical cycle. The alternating flux in the core in turn induces an alternating current in each of the secondary coils. The voltage at each of the secondary coils is directly related to the primary voltage by the turns ratio, or the number of turns in the primary coil divided by the number turns in the secondary coil. For instance, if the primary coil consists of 100 turns and carries 480 volts and a secondary coil consists of 25
A transformer is based on a very simple fact about electricity: when a fluctuating electric current flows through a wire, it generates a magnetic field (an invisible pattern of magnetism) or “magnetic flux” all around it. The strength of the magnetism (which has the rather technical name of magnetic flux density) is directly related to the size of the electric current. So the bigger the current, the stronger the magnetic field. Now there’s another interesting fact about electricity too. When a magnetic field fluctuates around a piece of wire, it generates an electric current in the wire. So if we put a second coil of wire next to the first one, and send a fluctuating electric current into the first coil, we will create an electric current in the second wire. This is called electromagnetic induction because the current in the first coil causes (or “induces”) a current in the second coil. The current in the first coil is usually called the primary current and the current in the second wi
A transformer is a simple device that transfers electrical energy from one circuit to another by means of magnetic induction. An alternating current (AC) in the primary circuit creates a changing magnetic field in the iron core. This magnetic field induces a changing (AC) voltage in the secondary circuit. Connection of a load across the secondary will result in an AC current flowing, transferring electrical energy from the primary circuit to the secondary circuit. The output voltage of a transformer is determined by the ratio of turns between the primary & secondary. The secondary induced voltage Vs, of an ideal transformer, is scaled from the primary Vp by a factor equal to the ratio of the number of turns of wire in their respective windings. Thus the voltage ratio can be expressed: For example, a transformer with 240v input and 24v output will have about ten times more turns on the primary than the secondary (disregarding losses). The number of turns on the primary is determines the
