Table 2 Transient eigenvalues

5th Mode

(1.246e−04 ± 296.61i)/− 4.20080e−07

(− 0.78961 ± 296.59i)/2.66228e−03

(− 1.12589 ± 296.58i)/3.79621e−03

4th Mode

(− 0.3629 ± 200.04i)/1.814134e−03

(− 3.5223 ± 200.02i)/1.76070e−02

(− 4.2456 ± 200.01i)/2.12221e−02

3rd Mode

(− 0.2369 ± 160.59i)/1.47518e−03

(− 5.3258 ± 160.76i)/3.31107e−02

(− 6.4752 ± 160.74i)/4.02510e−02

2nd Mode

(− 0.1285 ± 122.11i)/1.05232e−03

(− 4.2153 ± 121.17i)/3.47672e−02

(− 5.3698 ± 121.16i)/4.42764e−02

1st Mode

(− 0.5468 ± 97.26i)/5.62195e−03

(− 3.4552 ± 97.21i)/3.55212e−02

(− 4.1592 ± 97.20i)/4.27510e−02

0th Mode

(− 0.4586 ± 5.29i)/8.63679e−02

(− 3.2356 ± 5.21i)/5.27575e−01

(− 4.14785 ± 5.20i)/6.23580e−01

Other mode

Stable

stable

stable

Electric mode-eigenvalue/damping ratios

Electrical-Mode

(− 0.0221 ± 191.2i)/1.15585e−04

(− 2.1615 ± 190.6i)/1.13397e−02

(− 4.2629 ± 190.4i)/2.23835e−02