Funding for this research was provided by:
National Natural Science Foundation of China (51805453, 51978575, 51975487)
Fundamental Research Funds for the Central Universities (2682018CX14)
Postdoctoral Research Foundation of China (2019M663551)
State Key Laboratory of Traction Power (TPL1904)
Article History
Received: 7 January 2020
Accepted: 1 July 2020
First Online: 10 July 2020
Compliance with Ethical Standards
:
: The authors declare that they have no conflicts of interest.