A High-Precision Rotor Position and Displacement Prediction Method Specially for Bearingless Permanent Magnet Synchronous Motor

Table 2

Comparison of prediction results of various algorithms at 3 000 r/min.

	Algorithm	Maximum error	Mean square error	Calculating time /s
Rotor position angle θr; prediction /rad	KELM	3.48e-03	1.56e-04	0.575
	ELM	0.0368	0.0033	2.734
	LS-SVM	6.96e-03	5.09e-04	0.781
Displacement α; prediction /m	KELM	4.99e-09	5.52e-10	0.531
	ELM	7.62e-08	4.03e-09	2.653
	LS-SVM	7.27e-09	8.58e-10	0.688
Displacement β; prediction /m	KELM	4.94e-07	4.34e-08	0.609
	ELM	4.02e-06	5.49e-07	2.375
	LS-SVM	6.57e-07	7.01e-08	0.719