New  technical  developments,  such  as  in  the  field  of  frequency  drives  of  technological  units,  electrified transport, wind, and solar power plants, apply devices built on the basis of powerful transistors. Modern devices designed on these elements  are  powerful  generators  of  higher  harmonics  of  currents  that  penetrate  the  grids  of  power  systems.  It  requires  the development of measures and means to limit the higher harmonics of currents in the electrical grids. 

Simulation of transients for designing multiple power filter circuits

The practice of operating multiple single-tuned filters in industrial power supply systems has shown that technological transformer capacitors in switching filters within the systems can cause the damage of filters. The most disturbing loads on the power supply systems are powerful AC arc furnaces. Static Var compensators used in the power supply systems contain multiple harmonic filters for harmonic mitigation and reactive power compensation.

Vibration diagnostic model of ball radial piston pump of hydraulic gear.

The universal mathematical model of dynamic processes in a radial plunger hydromashine pump with ball-pistons is created. This model takes into account inertial properties of piston balls, a stator, elastic liquid properties in a cylinder control, eccentricity, replenishment pressure and pressure in cavity pumping, and rotor frequency rotation. The law of pressure changes is established; this law takes into consideration its reproaches in pump cylinders.