The Experts below are selected from a list of 252 Experts worldwide ranked by ideXlab platform
Kevin Tomsovic - One of the best experts on this subject based on the ideXlab platform.
-
three phase power converter based real time synchronous generator emulation
IEEE Transactions on Power Electronics, 2017Co-Authors: Liu Yang, Jing Wang, Jingxin Wang, Xiaohu Zhang, Leon M Tolbert, Fei Fred Wang, Kevin TomsovicAbstract:This paper develops a synchronous generator emulator by using a three-phase voltage source converter for transmission level power system testing. Different interface algorithms are compared, and the voltage type Ideal Transformer model is selected considering accuracy and stability. At the same time, closed-loop voltage control with current feed-forward is proposed to decrease the emulation error. The emulation is then verified through two different ways. First, the output waveforms of the emulator in experiments are compared with the simulation under the same condition. Second, a transfer function perturbation-based error model is obtained and redefined as the relative error for the amplitude and phase between the emulated and the target system over the frequency range of interest. The major cause of the error is investigated through a quantitative analysis of the error with varying parameters.
T. Veijola - One of the best experts on this subject based on the ideXlab platform.
-
Synthesis of Reduced Equivalent Circuits for Transmission Lines
IEEE Transactions on Circuits and Systems I: Regular Papers, 2006Co-Authors: A. Kallio, T. VeijolaAbstract:This paper presents a method for generating lumped models for symmetrical transmission-line two-ports. These models consist of an Ideal Transformer and frequency-domain approximations for two physical driving-point impedances. The lumped element values are obtained directly from the distributed parameters or propagation constant and characteristic impedance. The method is applied to dispersive transmission lines, skin effect and waveguides. It is shown that the equivalent circuit is superior in accuracy and number of elements compared to spatial discretizations like ladder approximation
Boštjan Blažič - One of the best experts on this subject based on the ideXlab platform.
-
Stability analysis of an Ideal-Transformer-Model interface algorithm
2019 7th International Youth Conference on Energy (IYCE), 2019Co-Authors: Janja Dolenc, Ambrož Božiček, Boštjan BlažičAbstract:The subject addressed in the proposed paper is to define stability conditions of an Ideal Transformer Model interface algorithm used for coupling two real-time simulators. The Ideal Transformer Model algorithm is one of the most straightforward methods for hardware-in-the-loop simulations. Integration of the Ideal Transformer Model into the system does not affect systems impedance characteristics and this is its most prominent advantage. However, specific change of system and load impedance ratio may result into system instability. Furthermore, it is shown that the transition of the system into an unstable state is the consequence of the time-delay between simulators. Time-delay turns out as a disturbance that amplifies an error due to transmission of the voltage signal between the simulators. Taking into account Nyquist stability criterion, three cases with different system and load impedance ratio are presented, first with the simulations in Matlab Simulink and later on with simulations on RT simulators.
-
Stabilization of Hardware-in-the-Loop Ideal Transformer Model Interfacing Algorithm by Using Spectrum Assignment
IEEE Transactions on Power Delivery, 2019Co-Authors: Matevž Bokal, Igor Papič, Boštjan BlažičAbstract:This paper deals with stabilization of an Ideal Transformer model (ITM) circuit, used as an interfacing algorithm for hardware-in-the-loop simulations. The ITM allows for the distribution of simulation model computations over multiple processors or can be used in power hardware-in-the-loop simulations. When specific impedance conditions of the partitioned circuit are not met, this interfacing algorithm becomes unstable. This paper first presents a new theoretical approach for representing the ITM interfacing algorithm that is based on delay differential equations. With a stability analysis of the obtained time-delay system, a stabilization method is proposed, which increases the stability boundaries of the ITM algorithm. Simulation examples, including the scenario of a two-level inverter system, are provided.
Carl Ngai Man Ho - One of the best experts on this subject based on the ideXlab platform.
-
Modelling and Experimental Evaluation of Ideal Transformer Algorithm Interface for Power Hardware in the Loop Architecture
2020 IEEE Applied Power Electronics Conference and Exposition (APEC), 2020Co-Authors: Mandip Pokharel, Carl Ngai Man HoAbstract:Interface devices are crucial to achieving Power Hardware in the Loop (PHIL) configuration. It is the interface that separates PHIL implementation with its real counterpart. This inclusion of interface at power decoupling point has raised the concern of stability and accuracy among researchers. It is therefore essential to study the effect of interface if the PHIL system is to be entirely understood. Ideal Transformer Algorithm (ITA) is one of the widely used interfacing method for PHIL due to its implementation simplicity. Moreover, the existing models of ITA relies only on the theoretical model developed. This work constitutes the study and development of accurate mathematical model of individual interface devices in ITA. Further, this paper uses a frequency sweep approach to determine the responses from the actual system consisting of a Real Time Digital Simulator (RTDS). This experimentally obtained frequency response is then compared with model response to test the accuracy of the developed model. This paper therefore bridges the existing gap in interface model by experimentally verifying the developed model. The theoretical and experimental model are well within agreement to further the studies in PHIL.
Liu Yang - One of the best experts on this subject based on the ideXlab platform.
-
three phase power converter based real time synchronous generator emulation
IEEE Transactions on Power Electronics, 2017Co-Authors: Liu Yang, Jing Wang, Jingxin Wang, Xiaohu Zhang, Leon M Tolbert, Fei Fred Wang, Kevin TomsovicAbstract:This paper develops a synchronous generator emulator by using a three-phase voltage source converter for transmission level power system testing. Different interface algorithms are compared, and the voltage type Ideal Transformer model is selected considering accuracy and stability. At the same time, closed-loop voltage control with current feed-forward is proposed to decrease the emulation error. The emulation is then verified through two different ways. First, the output waveforms of the emulator in experiments are compared with the simulation under the same condition. Second, a transfer function perturbation-based error model is obtained and redefined as the relative error for the amplitude and phase between the emulated and the target system over the frequency range of interest. The major cause of the error is investigated through a quantitative analysis of the error with varying parameters.
