Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Generalized Voltage-based State-Space Modelling of Modular Multilevel
  Converters with Constant Equilibrium in Steady-State
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
26
The categories of this paper are: bayes-an
27
The categories of this paper are: comp-gas
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
3
The categories of this paper are: physics
20
The categories of this paper are: acc-phys
4
The categories of this paper are: cond-mat
16
The categories of this paper are: stat
19
The categories of this paper are: eess
6
The categories of this paper are: astro-ph
11
The categories of this paper are: hep-lat