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Modeling and simulation of power systems for general-purpose transient studies has been receiving significant attention in the literature. Among recently proposed methods, the so-called shifted-frequency analysis (SFA) approach has been shown to facilitate accurate and numerically efficient simulation of electromagnetic and electromechanical transients with the use of dynamic phasors. This paper proposes...
A new revision of NERC standard EOP-005-2 requires ISOs and TOs (transmission owners) to review and update power system restoration plans in a more timely manner following planned or unplanned network changes. Power system planning and operations face a higher level of challenge to conduct overall evaluation of power system steady state, dynamics and overvoltages during system restoration. This paper...
Low Voltage DC (LVDC) distribution systems have the potential to be considered as an efficient platform for facilitating the connection of more distributed energy resources. The applications of LVDC are still at an early stage due to the lack of mature experience and standards. Over and above, the protection challenges that are presented by integrating DC installations in existing AC systems are one...
The addition of large amounts of wind and solar generation to bulk power systems that are traditionally subject to operating constraints set by transient limitations is the subject of considerable concern in the industry. The US Western Interconnection (WI) is expected to experience substantial additional growth in both wind and solar generation. These plants will, to some extent, displace large central...
Real-time fuzzy logic controllers (RFLC) have been developed for the VGT and EGR control on a heavy-duty diesel engine. Previous studies show that compared to the VGT and EGR controlled by conventional PID controllers, there is a increase of engine torque and a reduction of engine emissions when the engine is running on the same condition. This work carried out robustness evaluation of the RFLC control...
Functional verification and Virtual Test, which is verification of a test procedure, of mixed-signal circuits share the need for efficient simulation capabilities. Switching DC/DC converters are a particularly hard problem, because traditional SPICE-type simulation approaches incur simulation efforts which prevent one from covering all conceivable use-cases. The new IEEE 1800-2012 standard for SystemVerilog...
Physical and electrical characteristics of high-temperature superconducting (HTS) DC power cables have been modelled to assess their benefits compared to conventional XLPE cables for use in distribution networks of tightly coupled electrical systems such as the Navy all-electric ship. The characteristics of a 30-m long HTS DC cable prototype that was successfully demonstrated recently were used to...
This paper describes the influence of replacing centralised generation by distributed generation (DG) with a full converter (e.g. type 4 wind turbines, solar power) from a short-circuit power and a voltage support point of view. To allow investigating the influence the settings of the voltage support of the DG units, an iterative approach based on linear network calculations is used. Inherently, the...
Eddy current induced electromagnetic (EM) loads during plasma events are the design driver for ITER port plug (PP) structure, diagnostic first wall (DFW), shield module (DSM) and diagnostic system supported by the PP structure. Generic models using commercial software OPERA, MAXWELL and ANSYS are developed and benchmarks are performed for global EM analysis to obtain port-specific design driving EM...
Various distributed generation (DG) systems with capacities in the range of several kilowatts to tens of megawatts can increase voltage along a feeder when they are injecting power into distribution systems. Thus, the main objective of this study is to analyze the transient behavior of such a distribution system integrated by DG systems. This study (1) models the IEEE 37-bus test feeder as a distribution...
In this paper neuro-fuzzy state variable estimators of drive system with an elastic coupling are presented. The described case is related to calculating the load speed and shaft torque based on easy to measure signals. During the design process, fuzzy C-means clustering was applied in order to optimize the structure of tested estimators. The obtained results show very high precision of estimation...
This paper proposes and evaluates a systematic method for controlling an energy storage system for preventing load shedding due to transient declines in frequency. The proposed controller works on local measurements and uses an extended Kalman filter to perform online identification of system parameters. These results are then used to implement a model predictive controller for the safe withdrawal...
Handling overloads in dynamic real-time embedded systems which are subject to frequent workload changes is a critical issue as it allows graceful quality of service (QoS) degradation and provides a mechanism to determine the load to be shed to handle the overload. This paper presents a novel hybrid automata based ERfair scheduling framework for a real-time system which may be subjected to transient...
Micro-grids are becoming very popular due to the plug-and-play nature of their integration. But the high penetration of distributed generators may also create potential instability as it is unable to regulate the system. This paper compares the dynamic performance of a micro-grid when the system load demand is suddenly changed. Multiple distributed sources are used to create a flexible simulation...
The continuous monitoring of power quality (PQ) disturbances in electrical power distribution system has become an important issue for utilities and customers. The power system operation can be improved and maintained by analyzing the PQ disturbances systematically. In this paper, an attempt has been made to review the modeling and simulation of the PQ disturbances due to the exploitation of various...
In the voltage regulation problem of MV distribution systems with Distributed Generation (DG), the regulator of the On Load Tap Changer (OLTC) equipped with Line Drop Compensator (LDC) interferes with the DG voltage regulator. This interaction can significantly changes the voltage profile along the feeders. With the aim to propose a solution to this problem, the present paper firstly models this interaction...
Proportional-integral (PI) controllers represent huge majority of all controllers applied in practice. Despite their broad use, different alternative solutions have been developed based on reconstruction and compensation of input, or output disturbances. Whereas a compensation of output disturbances reconstructed by a parallel plant model represents a key element of the well known internal model control...
DC power has recently become a potential option and made a vital contribution to the growth of future power systems. On the other hand, DC power is more advantageous than AC power in terms of integrating of renewable energy sources into distribution power networks. Transients in a DC network are different from AC networks' due to a greater consumption sides as well as a greater participation of electronics...
The use of real time digital simulation of large power systems is widely spreading due to its high precision result and increasing computing capability. However, in many cases, especially when large power system networks are to be modeled, the interconnection data and parameter data are available in flies which are used as input to simulation programs. Most transmission utilities use dynamic studies...
The dynamical behavior of temperature is becoming a critical design consideration for the power electronics, because they are referred as “thermal cycling” which is the root cause of fatigues in the power electronics devices, and thus is closely related to the reliability of the converter. It is well understood that the loading of power devices are disturbed by many factors of the converter system...
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