Radial excitation force generated by permanent magnet motor using d-axis current injection

Tsunoda, Wataru; Chibá, Akira; Shinshi, Tadahiko

doi:10.1109/icit.2018.8352228

Cited by 2 publications

(2 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…with In the motor, the magnetic fluxes in the air gaps in the positive and negative X-direction are strengthened and weakened by the eccentricity, respectively. The force generated in the X-direction can be expressed as [19]…”

Section: Algorithm For Estimating the Dynamic Parameters Of The Bearingmentioning

confidence: 99%

Estimation of the Dynamic Parameters of the Bearings in a Flexible Rotor System Utilizing Electromagnetic Excitation by a Built-In Motor

et al. 2021

Self Cite

View full text Add to dashboard Cite

Estimation of the dynamic parameters of bearings is essential in order to be able to interpret the performance of rotating machinery. In this paper, we propose a method to estimate the dynamic parameters of the bearings in a flexible rotor system. By utilizing the electromagnetic excitation generated by a built-in PM motor and finite element (FE) modeling of the rotor, safe, low-cost, and real-time monitoring of the bearing dynamics can be achieved. The radial excitation force is generated by injecting an alternating d-axis current into the motor windings. The FE model of the rotor and the measured frequency responses at the motor and bearing locations are used to estimate the dynamic parameters of the bearings. To evaluate the feasibility of the proposed method, numerical simulation and experiments were carried out on a flexible rotor system combined with a bearingless motor (BELM) having both motor windings and suspension windings. The numerical simulation results show that the proposed algorithm can accurately estimate the dynamic parameters of the bearings. In the experiment, the estimates made when utilizing the excitation force generated by the motor windings are compared with the estimates made when utilizing the excitation force generated by the suspension windings. The results show that most of the stiffness and damping coefficients for the two experiments are in good agreement, within a maximum error of 8.92%. The errors for some coefficients are large because the base values of these coefficients are small in our test rig, so these coefficients are sensitive to deviations. The natural frequencies calculated from the dynamic parameters estimated from the two experiments are also in good agreement, within a maximum relative error of 3.04%. The proposed method is effective and feasible for turbomachines directly connected to motors, which is highly significant for field tests.

show abstract

Section: Algorithm For Estimating the Dynamic Parameters Of The Bearingmentioning

confidence: 99%

Estimation of the Dynamic Parameters of the Bearings in a Flexible Rotor System Utilizing Electromagnetic Excitation by a Built-In Motor

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…Rotor centricity is mainly divided into static and dynamic eccentricity. In previous research (Tsunoda et al, 2018(Tsunoda et al, , 2019b, we discussed measurement of the FRF of a rotor system with dynamic eccentricity. The effect of the eccentricity and the rotational speed on the FRF was not evaluated.…”

Section: Introductionmentioning

confidence: 99%

Frequency response function measurement of a rotor system utilizing electromagnetic excitation by a built-in motor

Ren

Tsunoda

Han

et al. 2020

JAMDSM

Self Cite

View full text Add to dashboard Cite

In this paper, we propose a practical method for evaluating the robustness and stability of rotating machines. This entails using electromagnetic excitation and measuring the frequency response functions (FRFs) of the rotor system during rotation. The difficulty of applying excitation can be solved by utilizing a built-in motor with static eccentricity and adding a sinusoidal sweep d-axis current to the motor. A test rig with a bearingless motor (BELM) was used to verify the validity of the proposed method. A consequent-pole-type BELM is a combination of a consequent-pole-type motor and a radial magnetic bearing, in which both the motor and the suspension windings are arranged in one stator core of the BELM. The center of the motor is defined by the zero-power controller and the static eccentricity is determined by the suspension control system. The FRFs measured utilizing the electromagnetic excitation generated by the motor windings was compared with reference FRFs measured utilizing the suspension windings. The natural frequencies and damping ratios were determined from the two different FRFs. The difference between the identified natural frequencies and the difference between the damping ratios for the two different FRFs were calculated. The effectiveness of measuring the dynamic characteristics of the rotor system under various rotational conditions, such as the rotational speed and eccentricity, was clarified and the differences between the measurements obtained from the two different FRFs were generally less than 7.7%.

show abstract

Radial excitation force generated by permanent magnet motor using d-axis current injection

Cited by 2 publications

References 13 publications

Estimation of the Dynamic Parameters of the Bearings in a Flexible Rotor System Utilizing Electromagnetic Excitation by a Built-In Motor

Estimation of the Dynamic Parameters of the Bearings in a Flexible Rotor System Utilizing Electromagnetic Excitation by a Built-In Motor

Frequency response function measurement of a rotor system utilizing electromagnetic excitation by a built-in motor

Contact Info

Product

Resources

About