The main classification of inverter
> According to the nature of wave form
There are two main categories, one is a sine wave inverter and the other is a square wave inverter.
The sine wave inverter outputs an even better sinusoidal alternating current than the grid we use every day because it does not have electromagnetic pollution in the grid.
The square wave inverter outputs a square wave alternating current of poor quality, and its positive maximum value to negative maximum value are generated at the same time, which causes severe instability effects on the load and the inverter itself. 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 contained in the square wave current will increase the capacitive current flowing into the load, and in severe cases, the load filter capacitor of the load will be damaged.
In view of the above shortcomings, there are quasi-sinusoidal (or improved sine waves, modified sine waves, analog sine waves, etc.) inverters whose output waveform has a time interval from the positive maximum value to the negative maximum value. The effect of the use has been improved, but the waveform of the quasi-sine wave is still composed of polylines, which belongs to the square wave category and has poor continuity.
In summary, sine wave inverters provide high quality AC power that can drive any kind of load, but with high technical requirements and cost. The quasi-sinusoidal inverter can meet most of our electricity demand, with high efficiency, low noise and moderate price, thus becoming the mainstream product in the market. The square wave inverter is manufactured using a simple multivibrator. Its technology belongs to the level of the 1950s and will gradually withdraw from the market.
Inverters are classified into coal-electric inverters, solar inverters, wind energy inverters, and nuclear power inverters according to different power sources. According to different purposes, it is divided into independent control inverters and grid-connected inverters.
The world's solar inverters, Europe and the United States are more efficient, the European standard is 97.2%, but the price is more expensive, the efficiency of other domestic inverters are below 90%, but the price is much cheaper than imports.
In addition to power and waveform, the efficiency of the inverter is also very important. The higher the efficiency, the less energy is wasted on the inverter, and the power for the appliance is more, especially when you use a low-power system. The importance of one point is more obvious.
>According to the nature of the source
Active inverter: an inverter that makes the current in the current circuit connected to the grid on the AC side without directly connecting to the load;
Passive inverter: An inverter that causes current in a current circuit to be directly connected to a load on the AC side without being connected to the grid (ie, an inverter that inverts DC power to a certain frequency or an adjustable frequency)
>By grid type
Divided into off-grid inverters and grid-connected inverters
Divided into two-level inverter, three-level inverter, multi-level inverter
>by power level
Divided into high power inverter, medium power inverter, low power small inverter