Abstract
In this paper, a simplified model predictive current control (MPCC) is proposed for the primary permanent-magnet linear motor traction system in subway applications, which is fed by one two-level voltage-source-inverter (VSI). Based on the deadbeat concept, the reference voltage vector is calculated to eliminate the difference between the measured and reference currents in the next sampling period. Due to the discrete feature of the VSI, the reference voltage vector usually cannot be provided. Hence, the distance of a voltage vector is defined, and the voltage vector with the shortest distance is selected as the optimal one, which is called as the shortest distance principle in this paper. According to the shortest distance principle, the distribution of the reference voltage vector is divided into seven sectors, and the optimal voltage vector can be easily determined considering the location of the reference voltage vector. As a result, the computation cost is significantly reduced. However, the performances of MPCC are not affected by this simplification. The equivalence between the proposed and conventional MPCCs is proved in theory. All the theoretical analyses are verified by experimental results.
Highlights
The linear motor has attracted more attentions in subway applications due to the following advantages: (1) the direct production of thrust force; (2) smaller turning radius and less requirement of cross-sectional area of a tunnel; (3) better climbing ability and faster acceleration; and (4) less maintenance and lower noise [1,2,3,4,5]
The main contribution of this paper is to propose an equivalent model predictive current control (MPCC) for the primary PMLM (PPMLM)
For the reduction of the computation burden, a simple but equivalent solution was proposed for the MPCC of PPMLM traction systems
Summary
The linear motor has attracted more attentions in subway applications due to the following advantages: (1) the direct production of thrust force; (2) smaller turning radius and less requirement of cross-sectional area of a tunnel; (3) better climbing ability and faster acceleration; and (4) less maintenance and lower noise [1,2,3,4,5]. Seven current predictions and same cost function calculations are required to determine the optimal VV for three-phase motor drives [24]. The heavy computation cost will require longer calculation time, and reduces the average switching frequency of the VSI, especially in multi-phase motor or multi-motor drives. An equivalent simplified MPTC is proposed for PM motor drives, in which the deadbeat concept is involved and the candidate VVs are reduced from 7 to 4 [28]. The main contribution of this paper is to propose an equivalent MPCC for the PPMLM traction systems in subway applications, in which a shortest distance principle is designed and the cost function is eliminated. The computation cost can be further reduced comparing with the modified MPTC in [28] while the performances of PPMLM traction systems are not affected.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
