Setup and performances of the real-time simulation platform connected to the INELFE control system (original) (raw)
Related papers
2011
In this paper, full real-time digital simulation of a static modular multilevel converter (MMC) HVDC link interconnecting two AC networks is discussed. The converter has 60 cells per arm; each cell has two power switches with antiparallel diodes and one capacitor. The simulated model can be used to study the natural rectifying mode, which is very important in the energizing process of the converter, whether a ramping voltage or a charging resistance is used. The model also incorporates a simple controller to show the system behavior in different operating conditions. The converter model and the controller are simulated on two independent real-time simulators and connected though their respective IO and physical signal cables to perform Hardware-in-the-Loop testing. All capacitor voltages are supplied to the controller using digital to analog converters. Firing signals from the controller are sent using digital signals with opto-couplers, as would be the case with a real setup. By doing so, a Hardware-in-the-Loop (HIL) simulation is obtained. The main challenges of this setup are the very high number of IOs, which reaches over 730, considering both controller and converter, and the processing power required to simulate the 360 cells within a small time-step of 50 µs or less, as required for electromagnetic transient analysis. The simulation is achieved with a time-step of 20 µs using 10 INTEL 3.2-Ghz processor cores. Different faults are applied to determine their effects on the controller and the converter. In order to produce results that are as realistic as possible, a saturable transformer is used; the impact is particularly noticeable during faults and unbalanced load. The real-time digital simulator used is based on MATLAB, SIMULINK, SimPowerSystems and eMEGAsim.
FPGA-Based Real-Time Simulation of Multilevel Modular Converter HVDC Systems
AC-HVDC-AC energy conversion systems using modular multilevel voltage-source converters (MMC) are becoming very popular to integrate distributed energy systems to the main grid. MMC AC-DC-AC converters are also being considered for large HVDC transmissions systems. Such multi-level converters pose a serious problem for HIL simulators required for control, protection design and testing due to the large number of cells that must be simulated individually using very small time steps. Such a system also requires managing a very large number of I/O channels within a few microseconds. This paper demonstrates the advantages of using a very small time step to simulate a modular multilevel converter (MMC). To do so, a hybrid simulation is done using Intel PC and FPGA. The MMC is implemented on FPGA to simulate fast transient with a time step of 500 ns to 1 µs. The AC network and HVDC bus is simulated on the PC, with a slower time step of 10 µs to 20 µs. The simulator architecture and the components simulated on the FPGA and on the PC will be discussed, as well as the method allowing the interconnection of this slow and fast system
2014 Power Systems Computation Conference, 2014
The HVDC links are increasingly used not only to interconnect asynchronous AC systems but are also embedded into a same meshed AC power system. Thanks to its speed and flexibility, the HVDC technology is able to provide transmission system advantages as transfer capacity enhancement and power flow control. In addition, studies have shown that the way of controlling the HVDC converters impacts the stability of the AC system. This can be particularly exploited to enhance the dynamic power system performances during transients. In this paper a robust multivariable control design for HVDC link converters is proposed. It is based on the coordination of the control actions of the HVDC converters and the use of a control model which takes into account the dynamics that mostly impact stability of the neighbor zone of the HVDC link. This new methodology was used to synthesize the controller for an actual grid 1000 MW HVDC link reinforcement project called "Midi-Provence" in the southern part of the French grid. The synthesis, implementation and validation processes are presented in detail. The new controller is tested in comparison with the standard vector control. A large-scale dynamic model of the whole European power system, currently used and updated by the European TSO's for the interconnection studies has been used with Eurostag simulation software.
Modeling of Modular Multilevel Converters for the France-Spain link
2013
The VSC based HVDC link between France and Spain (INELFE project: France-Spain ELectrical INterconnection) will be the most powerful VSC link by 2014. Commissioning of the link is planned in the late 2014. The French TSO RTE is currently conducting studies on this future installation. The large number of switching elements in Modular Multilevel Converters (MMC) introduces several complexities for modeling the converter in electromagnetic transient type (EMT-type) simulation programs. Depending on the type of phenomena being analyzed on the HVDC link, various types of EMT and phasor models are available. A brief description of the nature of these models is presented along with their application fields. The generic models developed and used in EMT tools by RTE are presented and discussed. Both offline and real-time implementations are addressed. Next, some electromagnetic transient studies based on the generic models are presented and analyzed: starting sequences, dynamic performances...
Hybrid EMT-TS Simulation Strategies to Study High Bandwidth MMC-Based HVdc Systems
2020 IEEE Power & Energy Society General Meeting (PESGM)
Modular multilevel converters (MMCs) are widely used in the design of modern high-voltage direct current (HVdc) transmission system. High-fidelity dynamic models of MMCsbased HVdc system require small simulation time step and can be accurately modeled in electromagnetic transient (EMT) simulation programs. The EMT program exhibits slow simulation speed and limitation on the size of the model and brings certain challenges to test the high-fidelity HVdc model in system-level simulations. This paper presents the design and implementation of a hybrid simulation framework, which enables the co-simulation of the EMT model of Atlanta-Orlando HVdc line and the transient stability (TS) model of the entire Eastern Interconnection system. This paper also introduces the implementation of two high-fidelity HVdc line models simulated at different time steps and discusses a dedicated method for sizing the buffer areas on both sides of the HVdc line. The simulation results of the two HVdc models with different sizes of buffer areas are presented and compared.
Thyristors-based converters are still today the most common type of HVDC links. Modular Multilevel Converter based HVDC links are often considered for lower power rating projects like off-shore wind farms. Both approaches present challenges in both the design and the testing of proposed circuit topologies and control & protection system design. Conventional real-time simulators used by most power electronic system manufacturers for testing thyristor-based AC-DC converter systems in HIL mode encounter difficulties or simply cannot simulate MMC-based circuits composed very large number of fast power electronic devices. This paper will demonstrate new solvers methods adapted for both thyristors and MMC-based HVDC links. In the case of thyristors-based HVDC, a new solver called State-Space Nodal implements an efficient real-time method to deal with the numerous switched filter banks and valves groups found in these apparatus. The real-time and parallel simulation of Modular Multilevel Converters with hundreds of switches, which is very difficult or impossible with conventional solvers, is made with a pragmatic fixed-causality solver. System transients and dynamic performance under several operating conditions evaluated in HIL mode with a prototype controller-in-the-loop composed of several hundred of I/O connections will also be presented, using the RT-LAB real-time digital simulator.
IEEE Open Access Journal of Power and Energy, 2022
Graduate Student Member, IEEE), LEVI M. BIEBER 1 (Graduate Student Member, IEEE), JARED PAULL 1 (Student Member, IEEE), LIWEI WANG 1 (Senior Member, IEEE), WEI LI 2 (Member, IEEE), AND JEAN-NICOLAS PAQUIN 2 (Senior Member, IEEE)
Impact on power system transient stability of AC-line-emulation controllers of VSC-HVDC links
2021 IEEE Madrid PowerTech, 2021
High voltage direct current links based on voltage source converters (VSC-HVDC) embedded in alternating current (AC) systems are receiving a great deal of attention recently because they can contribute positively to the flexibilisation of modern power systems. Among several possibilities, AC-line-emulation control has been highlighted as an simple-but-useful alternative for these type of systems. With this strategy, the power flow through the link is controlled proportionally to the angle difference between its two AC terminals and this provides self-adaptation of the power flow in case of contingencies in the parallel AC lines, naturally. Although this controller is mainly concerned with steady state, it can also have an impact on the dynamic behaviour of the system which has not been sufficiently analysed. Along this line, this paper analyses the impact of AC-line-emulation controllers of VSC-HVDC on power system transient stability. Nonlinear time-domain simulations were carried out by using PSS/E on a small test system with an embedded point-to-point VSC-HVDC link. The critical clearing time (CCT) of a test fault has been used to assess transient-stability margins of the whole system. The paper provides recommendations for the design of AC-line-emulation controllers in order to ensure that transient stability is not jeopardised.
Industrial Electronics, 2006
This paper presents a real-time simulator for large power network based on Custom-Of-The-Shelf technologies, all embedded in the RT-LAB real-time simulation platform. This platform uses Pentium, Xeon, Opteron-based PCs (multi-CPUs and/or dual-core configurations) or even Xilinx FPGA cards for computational engines and InfiniBand communication fabric for fast inter-PCs communications. The real-time PCs runs under well-known operating systems QNX or RedHawk Linux while the main user control interface is either Simulink or LabView. The paper demonstrates the real-time simulation of complete single-pole 12-pulse HVDC system on dual-CPU, dual-core 2.2 GHz Opteron PC under 15 microseconds time step. It also demonstrates the real-time simulation of complex power system devices like SVC, STATCOM and more general power systems like the Kundur network. The paper also discusses the latest advances in Hardware-Inthe-Loop simulation like the possibility to program from within Simulink some controllers or devices, like a PMSM drive, directly in an FPGA card. This feature is enabled in RT-LAB by the use of Xilinx System Generator, a Simulink blockset. This FPGA targeting diminishes further the leap between prototype and production-type controller systems because the FPGA can implement rapidcontrol functions along with fast protection systems, like IGBT-current protection, of real controller.
Laboratory Demonstration of a Multi-Terminal VSC-HVDC Power Grid
IEEE Transactions on Power Delivery, 2017
This paper presents the design, development, control and supervision of a hardware-based laboratory Multi-Terminal-Direct-Current (MTDC) test-bed. This work is a part of the TWENTIES (Transmission system operation with large penetration of Wind and other renewable Electricity sources in Networks by means of innovative Tools and Integrated Energy Solutions) DEMO 3 European project which aims to demonstrate the feasibility of a DC grid through experimental tests. This is a hardware-in-the-loop DC system test-bed with simulated AC systems in real time simulation; the DC cables and some converters are actual, at laboratory scale. The laboratory scale test-bed is homothetic to a full scale high voltage direct current (HVDC) system: electrical elements are the same in per unit. The test-bed is supervised by a Supervisory Control And Data Acquisition (SCADA) system based on PcVue. Primary control based droop control method to provide DC grid power balance and coordinated control methods to dispatch power as scheduled by transmission system operator (TSO) are implemented. Since primary control acts as converter level by using local measurements, a coordinated control is proposed to manage the DC grid power flow. The implemented system is innovative and achievable for real-time, real-world MTDC-HVDC grid applications.