PUBLICATIONS

 This paper proposes the development of a power conversion system (PCS) for utilizing differential pressure (DP) energy in district heating systems with reduced DC-link voltage variation. A differential pressure control valve (DPCV) is usually used to regulate heat transmission pressure to remote areas in district heating systems. However, a high probability of DPCV malfunction and/or failure caused by cavitation exists because high-pressure fluids are used in district heating systems. Therefore, in this paper, a PCS for utilizing DP energy in district heating systems by replacing the DPCV is proposed. Furthermore, PCS DC-link voltage fluctuates when the hydraulic turbine experiences any sudden changes; and is effectively relieved by using a feed-forward control method. The PCS effectiveness for utilizing DP energy in district heating systems with reduced DC-link voltage variation is verified by both simulation

and experimental results.