Difference between pure sine wave and modified sine wave inverter:
1. Modified sine wave inverters generally use non-isolated coupling circuit, while pure sine wave inverters use isolated coupling circuit design. Its price is also a lot of difference. Modified sine wave switching inverter power supply, not only to eliminate the bulky industrial frequency transformer, and the inverter efficiency is greatly improved efficiency 90%.
2, modified sine wave switching inverter power supply using PWM pulse width modulation to generate the corrected wave output, in the inverter process, due to the use of special intelligent circuit and high-power field effect tube, greatly reducing the power loss of the system. And the soft-start function is added to effectively ensure the reliability of the inverter. If the power quality requirements are not very high, and it can meet the needs of most of the power equipment, but it still exists 20% harmonic distortion, there will be a problem in the operation of precision equipment, but also to the communication equipment caused by high-frequency interference.
The corrected sine wave is relative to the sine wave, and the output waveform of mainstream inverters nowadays, that is, the corrected sine wave. There are two main types of inverter waveforms, one is the sine wave inverter (i.e. pure sine wave inverter) and the other is the square wave inverter. A sine wave inverter outputs the same or even better sine wave alternating current than the grid we use every day, because it does not have the electromagnetic pollution found in the grid.
Extended information:
Correcting for Sine Wave Inverters
Correcting for Sine Wave Inverters should be avoided for "inductive loads". loads". Generally speaking, this means the application of electromagnetic induction principle of high-power electrical products, such as electric motors, compressors, relays, fluorescent lamps and so on. These products require a much higher starting current (about 5-7 times) than is needed to maintain normal operation. For example, a refrigerator that consumes about 150 watts of power during normal operation can start up to 1000 watts or more. In addition, because the inductive load in the power supply or disconnect the power of a moment, will produce a reverse electromotive force voltage, the peak value of this voltage is far greater than the vehicle inverter can withstand the value of the voltage, it is easy to cause the vehicle inverter transient overloading, affecting the service life of the inverter.
When using an ordinary multimeter to measure the AC output of a quasi-sinusoidal (corrected sine wave) car inverter, the voltage displayed is about 20V lower than 220V.
This can be a problem when running precision equipment and can also cause high frequency interference with communications equipment.
Reference:
Baidu Encyclopedia Sinusoidal Wave Inverter
Baidu Encyclopedia ? Modified sine wave inverter