12 volt inverter Modified sine wave inverter Overview
Modified sine wave is relative to the sine wave is concerned, and now the mainstream of the inverter output waveform, is modified sine wave. The waveform of the inverter Solar power inverters main two categories, one is a sine wave inverter (ie, pure sine wave inverter), and the other is a square wave inverter. Sine wave inverter output power is the same as we use every day or even better sine wave AC power because it does not exist in the electromagnetic pollution.
The square wave output of the inverter is the poor quality of the square wave alternating current, the positive maximum to the negative maximum value to almost simultaneously generated, so resulting in a dramatic effect on the instability of the inverter and the load itself. At the same time, its load capacity is poor, only 40-60% of the rated load, not with inductive loads. If the load carried by large, square-wave current third harmonic components contained enable capacitive currents flowing into the load increases, and in severe damage to the load of the power supply filter capacitor.
For the above disadvantages, in recent years a modified sine wave (or modified sine wave, quasi sine wave, sine-wave, etc.) of the inverter, the output waveform from the positive maximum to a negative maximum time between intervals, using the results improved, but is still a sine wave correction by the broken line composed, still belongs to the scope of the square wave, the continuity is not good, and there is a dead 220 volt power inverters zone (waveform diagram below). Modified sine wave inverters generally use non-isolated coupling circuit, and pure sine wave inverter with isolated coupling circuit design. Its price is also a lot of difference. Modified sine wave inverter switching power supply, not only eliminates the need for bulky power frequency transformer, but also greatly improve the efficiency of the inverter efficiency of 90%.
Modified sine wave inverter switching PWM pulse width modulation to generate modified sine wave output, the inverter process, due to the use of a dedicated intelligent circuit and power FET, greatly reducing the power consumption of the system. And an increase in soft-start function, effectively ensuring the reliability of the inverter. If electricity is not very high quality, and it is able to meet the needs of most electrical equipment, AC power inverters but it still exists 20% harmonic distortion, a problem occurs when you run precision equipment, can also cause high frequency of communications equipment interference.