宿舍限电的解决办法（Solutions to power rationing in dormitories）.doc

宿舍限电的解决办法（Solutions to power rationing in dormitories） Finally, our school, like other universities, limited power. Single power limit 600W, total power limit 2200w. But with a small hair dryer, the meter tripped. The power supply of the computer is 250W ~ 400W. The power of the 6 computers is definitely above an electric blower. But why can you bring 2 computers to work at the same time, but you cant get a 300W hair dryer? Whats the difference between the two? Lets look at it. Heating device, we usually use the most is the water heater, hair dryer, their work principle is the current through the resistance wire, resistance wire heating to boil water. For 220V grid, which is equivalent to a pure resistance load to the grid, learned circuit students all know, 220V to the AC resistance, current waveform of the voltage waveform and the flow resistance at both ends are in phase, that is to say, the 0 is the two phase difference. We call this type of load is purely resistive load. What kind of load is the computer equivalent to? The power of a computer is, for the grid, a load on the grid. The power supply of the computer is the switching power supply (note, this is not the power supply of the switch). It belongs to the non-linear load (also known as the rectifier load). The principle of switching power supply is the first 220V/50hz alternating current rectifier for high voltage direct current, the high voltage DC inverter for high voltage high frequency AC, and then reduced to low voltage and high frequency AC through high frequency transformer, and then converted to low voltage DC output, the efficiency of this kind of power is much higher than the traditional voltage regulator. A computer as a 220V switching power supply load of power grid, the load on the 220V AC input seems equivalent to a capacitive load, although its voltage waveform or sinusoidal current waveform, but it has the distortion, is no longer a rule but close to sine wave, pulse wave form (in fact, thi