Two ways to reduce a 12-volt system to 4 volts are to use voltage dividers or Zener diodes. Voltage dividers are made from resistors placed in series. The input voltage is divided into an output that depends on the value of the resistors used.

DC generator operates on the principle of the dynamically induced electromagnetic force. When a conductor is placed in a varying magnetic field, an electromotive force gets induced within the conductor. This induced e.m.f magnitude is measured using the equation of the electromotive force of a generator.

transformer

Increasing AC Voltage is the same as increasing DC voltage. To increase the voltage, we connect the AC voltages in series to get a higher output voltage. If the frequency of all the voltages are the same, the magnitude of the voltages simply add.

Electricity from the wind turbine generator travels to a transmission substation where it is converted into extremely high voltage, between 155,000 and 765,000 volts, for long distance transmission on the transmission grid. This grid comprises a series of power lines that connect the power sources to demand centers.

The primary reason that power is transmitted at high voltages is to increase efficiency. The higher the voltage, the lower the current. The lower the current, the lower the resistance losses in the conductors. And when resistance losses are low, energy losses are low also.

High voltages range from 115,000 to 230,000 VAC and Extra-High voltages range from 345,000 to 765,000 VAC. The United States transmits up to 500,000 volts on the high voltage grid.

240 volts

When you plug things into the outlet in your house, you don’t get DC. Household outlets are AC – Alternating Current. This current has a frequency of 60 Hz and would look something like this (if you plotted current as a function of time). So, AC allows use to more easily distribute electricity over large distances.

1. DC power is significantly more energy efficient than AC power. DC motors and appliances have higher efficiency and power to size characteristics. The greater efficiency resulting from recent developments in DC converter technology allows improvements in electricity delivery over long distances.

Advantages of DC Devices that use DC current include cell phones, laptops, TVs and much more. Direct current may also be used to transmit electricity with even greater efficiency than alternating current over extremely large distances by use of HVDC transmission (high-voltage direct current).

DC allows for a constant flow of current to a device. Most smaller electronic devices (such as computers) require direct current to operate with an AC-to-DC converter from wall power. Alternating current is used for equipment that have motors (refrigerators are an example).