TECHNOLOGICAL ASSURANCE OF RELIABILITY OF HIGH-SPEED MIXING DEVICES BASED ON ADAPTIVE LEVITATION SUPPORTS

Abstract

Rotating machines are an important and crucial component of numerous mechanical systems in modern industry, vehicles and a number of other applications. Excessive vibrations on rotating equipment due to numerous faults can lead to machine failures and lead to accidents. Thus, there is a need to understand the dynamic nature and identify faults for safe, uninterrupted and efficient operation of machines. This paper proposes a new approach to assess misalignment in a test using the same concept as in an imbalance test when balancing the rotor of high-speed machines in the oil and gas industry. The misalignment of the active magnetic bearing with the rotor was investigated. To accomplish this methodology, a four-degree-of-freedom dynamic model of an unbalanced and misaligned rigid rotor and two offset disks supported by two active magnetic bearings was mathematically developed. Disks with displacement lead to a gyroscopic effect at high rotor speeds. The equations of motion of the rotor-bearing system were derived and solved in order to obtain a displacement of the rotor in the time domain and control the current responses in the positions of the magnetic bearing. The algorithm for identifying the estimation of the unbalance and misalignment parameters of the active magnetic bearing was carried out by using the fast Fourier transform method. The effectiveness of this method was estimated at rotor speeds from 100 to 350 rad/s. In the process of determining the efficiency, random modeling errors of 1, 2 and 5 % were also introduced to the mass of the rotor and the moment of inertia of the disk.