With the continuous development of electronic technology, the harmonic problem is becoming more and more serious, which has been highly valued by all parties. There are several common methods to control it:

1, reducing the electrical distance between nonlinear electrical equipment and power supply. Reducing system impedance and using large-capacity synchronous generator can greatly shorten the electrical distance of nonlinear electrical equipment in the system and reduce the harm of harmonics to the power grid.

2. Harmonic isolation. The distribution transformer using D, yn 1 1 wiring group can effectively isolate harmonics, thus reducing the harm of harmonics.

3. Install the filter. At present, most of the harmonic control methods on substation side and user side are to install filters to reduce harmonic components. Filters are divided into active filters and passive filters. ?

The first step of harmonic control is harmonic measurement, which measures the content of each harmonic, and then focuses on the harmonic control with higher content, so as to achieve the effect of harmonic control. E6000 power quality analyzer can be used to measure harmonics, including1~ 50th harmonics, interharmonics, higher harmonics and harmonic subgroups.