This paper proposes performance improvement of hydraulic turbine generation system (HTGS) using a subdivided finite set model predictive current
control (SFS-MPCC). Recently, the differential pressure control valve (DPCV) is replaced by HTGS because of the frequent breakdown in DPCV caused by cavitation in the district heating systems. The HTGS consists of the hydraulic turbine, permanent magnet synchronous generator (PMSG), back-to-back (BTB) converter, and three-phase grid. Especially, BTB converter is composed of a generator-side inverter, DC-link capacitor, and grid-side inverter. In the generator-side inverter, a model predictive current control (MPCC) has been widely used because of many advantages such as robustness from
parameter variation, fast dynamic response, and unnecessariness of gain tuning. Since the conventional MPCC uses only eight voltage vectors, it makes a large current ripple which is directly related to torque ripple. Therefore, in this paper, to reduce the current and torque ripple, SFS-MPCC which uses
subdivided voltage vectors is proposed. Besides, the additional algorithm to reduce the calculation time is proposed because the subdivided voltage
vectors increase the calculation time excessively. The effectiveness of the proposed SFS-MPCC is demonstrated by simulation and experimental results.