Investigation of the energy characteristics of a reactive power compensating device with adjustable inductance in an electric traction network on an experimental setup

Abstract

Objective: Checking the theoretical provisions of the possibility of controlling the reactive power of an adjustable inductance compensating device. Testing and optimizing the algorithm of the reactive power regulating device. Assessing energy effi ciency of the device. Checking stability of the device in transient modes. Suggesting methods to improve stability of the system. Conducting a harmonic analysis of current and voltage curves obtained as a result of physical modeling, developing ways to suppress higher current and voltage harmonic. Methods: The scheme of the experimental setup was built, the electrical element base was selected, the measuring instruments used were determined, the experimental stand was assembled. Curves of changes in current, voltage, active and reactive power were taken on the physical model for operating modes without a compensating device, with an unregulated and adjustable compensating device. The change in current for critical transients is analyzed. To evaluate the fi ltering of higher harmonics of current and voltage by a compensating device, oscillograms were taken in operating mode with a load and after adding a diode bridge to the electric locomotive circuit, and their harmonic analysis was performed. Results: The adjustable device provides reactive power compensation in the load range of no less than 90 %. Additional measures are required to lower the active resistance of the compensating device reactor. The use of a reactor connected in series with a capacitor reduces the switching current and overvoltage in the device. The compensating device can operate in the mode of a broadband fi lter of higher harmonics. Practical importance: A physical model of an alternating current traction network with a reactive power compensating device and a controlled variable inductance has been created, which makes it possible to analyze both instantaneous and long-term processes in the traction network.