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This paper shows a theoretical vibration analysis regarding the controller’s parameters and the gyroscopic effect, based on a simplified rotordynamic model. Combined with 600 Wh energy storage flywheel rotor system mathematical model, the Campbell diagram of the rotor system was obtained by the calculation of the whirl frequency under different parameters of the controller in MATLAB to analyze the effect of the controller parameter on the whirl frequency and to limit the operating speed and acceleration or deceleration of the rotor. The result of the analysis can be used to set the support position of the rotor system, limit the ratio of transverse moment of inertia and the polar moment of inertia, and direct the flywheel prototype future design. The presented simplified rotordynamic model can also be applied to rotating machines.

The Victoria Mode (VM) is defined as the second empirical orthogonal function (EOF) of sea surface temperature anomalies (SSTAs) in the North Pacific. It is independent of the Pacific Decadal Oscillation (PDO) and represents the second climate mode of North Pacific variability. Using a first-order autoregressive model and forcing indices that track the Aleutian Low, North Pacific Oscillation (NPO), anomalous ocean circulation in the Kuroshio–Oyashio Extension (KOE), and the cold tongue (CT) and warm pool (WP) El Niño-Southern Oscillation (ENSO), this study reconstructs the North Pacific SSTAs and examines the relative contributions of different forcing mechanisms to the VM variance. It is found that the NPO and ENSO, especially the WP ENSO, are the dominant sources of VM variability, whereas the contributions of the Aleutian Low and zonal advection in the KOE region are relatively small. Further analysis shows that the forcing mechanisms acting on the VM are frequency dependent. At decadal and longer time scales, the VM variance comes mainly from the WP ENSO, whereas at interannual time scales, contributions from the NPO and CT ENSO are important. This study suggests that the VM is an oceanic response to the NPO forcing and atmospheric teleconnections excited by ENSO events.