Multifunctional megawatt scale medium voltage DC test bed based on modular multilevel converter (MMC) technology

Abstract

The recent development of modular multilevel converters (MMC) provides new opportunities for medium voltage DC (MVDC) systems for all electric ship design and offshore wind parks. Therefore, the Center for Advanced Power Systems at Florida State University has recently commissioned a new MVDC power-hardware-in-the-loop laboratory rated at 5 MW at DC voltages between 6…24 kV. The new lab features four individual MMCs, each composed of 36 full-bridge cells, and capable of delivering 210 A at 0…6 kV. This paper describes the entire system in detail, including the advanced current and voltage control concepts along with the state of the art digital control hardware. Selected commissioning results demonstrate the performance of the system under dynamic conditions and provide comparison with simulations obtained from a corresponding controller hardware-in-the-loop setup which is also described in the paper.Keywords-modular multilevel converter, medium voltage DC, shipboard power system, hardware-in-the-loop, fault management

Converter energy balancing in MMC system energy sharing using master controller

“…The new balancing module can be used for asymmetric load sharing between modules what can be used e.g. in power grid simulations [7]. It can be used also in the multi-converter system in case of failure: when one converter is damaged and has limited power rating (eg.…”

“…In the following paper an MMC converter system which has been installed in the Center of Advanced Power Systems in Florida State University [7] unit. DC output rating per converter is ±6 kV, 1.25 MW.…”

Analysis of experimental rapid power transfer and fault performance in DC naval power systems

“…Like all other labs at FSU-CAPS the MVDC lab is fully compatible with the PHIL and CHIL concept which allows for the utmost flexible and efficient implementation of different system architectures on the corresponding real-time simulators (in this case RTDS and OPAL-RT). A detailed description of the new MVDC facility along with additional experimental results can be found in [20], [21].…”

Impact of Key Design Constraints on Fault Management Strategies for Distributed Electrical Propulsion Aircraft

“…This reinforces the notion that since the electrical architecture will be strongly influenced by the feasible fault management solutions, and the FMS must define the electrical network design. By control of the solid state switches (manipulating firing angle 15,16,17 , pulse width modulation control 18 ) or current blocking diodes 19 within some topologies of power converters it is possible to limit fault current or de-energise the downstream network when a fault occurs. If converters are included in an architecture for power conditioning purposes, exploiting this potential dual functionality may provide a weight and efficiency benefit.…”