STUDYING THE LEVELS OF ELECTROMAGNETIC FIELDS AT POWER GENERATION FACILITIES AND DEVELOPING MEANS OF THEIR NORMALIZATION

Abstract

The levels of electromagnetic fields in the most critical areas of a thermal power generation enterprise are investigated. It is established that the intensity of the electric and magnetic components of the electromagnetic field of industrial frequency at the workplaces of the main control panel personnel does not exceed the limit levels. And the electromagnetic fields in the controlled frequency bands for the operation of computer equipment significantly exceed the limit values. Elevated concentrations of air ions are caused by discharge phenomena in technological equipment. The spectrum of radio frequency electromagnetic fields was obtained, which indicates the complexity of the electromagnetic situation. The magnetic field strengths around a 320 MW turbine generator were measured. For distances up to 5 m from it, the magnetic field strengths exceed the maximum permissible levels. It was determined that there is a zone of minimal field near the generator, which is advisable to use to determine the zones of safe movement of personnel. The asymmetry of the field of a four-pole electric machine is due to fundamental physical laws. The magnetic field strength near the busbar was measured. At a load of 280 MW and a voltage of 20 kV, the magnetic field intensity at a distance of 2 m from the outermost current conductor was 1.6-1.7 kA/m, which exceeds the limit level (1.4 kA/m). To reduce the impact of electromagnetic fields on personnel, it is recommended to use shielding. To cover large surfaces, it is advisable to use electrical steel of class 121, for shielding small objects (uninterruptible power supply) it is advisable to use a tape ferromagnetic amorphous alloy.