There are two kinds of inverters, one is sine wave inverters, the other is square wave inverters. Sinusoidal inverters output the same or even better sinusoidal AC as the power grid we use everyday, because it does not exist electromagnetic pollution in the power grid. Square-wave inverters output square-wave AC with poor quality, and the maximum of positive to negative is almost produced at the same time, which has a severe unstable impact on the load and the inverters themselves. At the same time, its load capacity is poor, only 40-60% of the rated load, can not carry inductive load. If the load is too large, the third harmonic component in the square wave current will increase the capacitive current flowing into the load, and seriously damage the power filter capacitance of the load. In view of the above shortcomings, quasi-sinusoidal wave (or modified sinusoidal wave, modified sinusoidal wave, analog sinusoidal wave, etc.) inverters have emerged. The output waveform of quasi-sinusoidal wave has a time interval between the positive maximum value and the negative maximum value, and the use effect has been improved. However, the waveform of quasi-sinusoidal wave is still composed of folded lines, which belongs to the category of square wave and has poor continuity. Generally speaking, sine wave inverters provide high quality AC, can drive any kind of load, but the technical requirements and costs are high. Quasi-sinusoidal wave inverters can meet most of our electricity demand, with high efficiency, low noise and moderate price, so they have become the mainstream products in the market. Square wave inverters are fabricated with simple multi-resonator, which belongs to the level of the 1950s and will gradually withdraw from the market.
Inverters are divided into coal-fired inverters, solar inverters, wind inverters and nuclear inverters according to the different power sources. According to different uses, it can be divided into independent control inverters and grid-connected inverters. In the world, solar energy inverters are more efficient in Europe and the United States. The European standard is 97.2%, but the price is more expensive. The efficiency of other domestic inverters is below 90%, but the price is much cheaper than that of imported ones. In addition to power and waveform, the efficiency of selecting inverters is also very important. The higher the efficiency, the less power will be wasted on the inverters and more power will be used in electrical appliances, especially when you use low-power systems.