Background. Linear generators used as autonomous sources of electric power and electromechanical shock absorbers convert vibration energy into electric energy with a linear reciprocating motion of the inductor. The EMF of the generator has a non-sinusoidal shape due to higher spatial and temporal harmonics. The change in the speed of the inductor is determined by the nature of the acting forces, but during the analysis, it is usually taken as harmonic with a sinusoidal distribution of magnetic induction. Reduction of EMF harmonics is possible in an electrical system with a linear generator and a magnetic liquid damper, by improving the designs based on a refined analysis.
Materials and methods. The reduction of spatial harmonics of EMF has been achieved by improving the tooth zone and armature winding, using magnetic fluid. The reduction of time harmonics has been achieved by providing the electrical system with the necessary change in the linear speed of the inductor. The analysis has been carried out using the ANSYS Electronics Desktop, ANSYS MAXWELL and Elcut packages.
Results. An electrical system to convert vibration energy based on a linear generator and a magnetic liquid damper has been developed; its functions, features and operating modes have been described. The authors have developed combined device designs, a three-phase combined winding with an EMF increased by 2 % and a sinusoidal distortion coefficient reduced by 20 %. Mathematical analytical and numerical methods to calculate characteristics based on finite element modeling have been proposed.
Conclusions. The developed electrical system allows efficient redistribution of vibration energy between the linear generator and the magnetic liquid damper and ensures reduction of higher harmonics in the EMF. The use of magnetic liquid controlled by a magnetic field allows us to regulate the resistance force to the inductor movement, to control viscous energy dissipation in liquid layers, to dampen vibrations, to increase the magnetic conductivity of the gap and the magnetic flux, to reduce the pulsations of the tooth harmonics of magnetic induction, to increase heat removal from magnets and winding, and to ensure efficient lubrication.