The waveform of the modified wave is different from that of the pure wave, the waveform of the pure wave is stable, and the inverter of the pure wave can carry the peak power of the inductive load appliance to start instantaneously. The modified wave inverter can not carry inductive load, only with resistive electrical appliances. The start-up peak power of inductive electrical appliances is large, and the modified inverter can not bear it.

1, correction inverter introduction:
Compared with square wave, the output voltage waveform of modified wave inverter is obviously improved, and the high harmonic content is also reduced. The traditional modified wave inverter is generated by the step superposition of the other wave voltage, which has many problems, such as complicated control circuit, many power switch tubes used in the superposition line, and large volume and weight of the inverter. In recent years, with the rapid development of power electronics technology, PWM pulse width modulation has been widely used to generate corrected wave output. At present, modified wave inverters have been widely used in remote areas of user systems, because these user systems are not very high requirements for power quality, modified inverters are suitable for resistive electrical loads.

2, pure inverter introduction:
Output voltage waveform of sine wave inverter. Its advantage is that the output waveform is good, the distortion is very low, and its output waveform is basically the same as the alternating current waveform of the mains power grid, in fact, the alternating current provided by the excellent sine wave inverter is higher than the quality of the power grid. Sine wave inverter to radio and communication equipment and precision equipment interference is small, low noise, load adaptability is strong, can meet all AC load applications, and the whole machine efficiency is high; Its disadvantage is that the line and relative correction wave inverter is complex, the control chip and maintenance technology requirements are high, and the price is more expensive. When solar power generation is connected to the grid, in order to avoid power pollution to the public grid, sine wave inverters must also be used.

 

3, power frequency inverter introduction:
Power frequency inverter booster inverter circuit. It first converts direct current into power frequency low-voltage alternating current; Then through the power frequency transformer to 220V, 50Hz AC power for load use. Its advantage is that the structure is simple, and various protection functions can be realized at a lower voltage. Because there is a power frequency transformer between the inverter power supply and the load, the inverter runs stably, reliably, has strong overload capacity and shock resistance, and can suppress the high-order harmonic components in the waveform. However, the power frequency transformer also has the problem of heavy and high price, and its efficiency is also relatively low. According to the current level of production of small power frequency inverter, its rated load efficiency is generally not more than 90%, and because the power frequency transformer in the full load and light load when the iron loss is basically unchanged, so that it is running under light load no-load loss is larger, the efficiency is also low.