The multifunctional numerical transformer protection and control system with adaptive and flexible features

The project supported the Nuclear Regulatory Commission (NRC) in identifying and evaluating the regulatory implications concerning the control and protection systems proposed for use in the Department of Energy's (DOE) Next-Generation Nuclear Plant (NGNP). The NGNP, using modular high-temperature gas-cooled reactor (HTGR) technology, is to provide commercial industries with electricity and high-temperature process heat for industrial processes such as hydrogen production. Process heat temperatures range from 700 to 950 C, and for the upper range of these operation temperatures, the modular HTGR is sometimes referred to as the Very High Temperature Reactor or VHTR. Initial NGNP designs are for operation in the lower temperature range. The defining safety characteristic of the modular HTGR is that its primary defense against serious accidents is to be achieved through its inherent properties of the fuel and core. Because of its strong negative temperature coefficient of reactivity and the capability of the fuel to withstand high temperatures, fast-acting active safety systems or prompt operator actions should not be required to prevent significant fuel failure and fission product release. The plant is designed such that its inherent features should provide adequate protection despite operational errors or equipment failure. Figure 1 shows an example modular HTGR layout (prismatic core version), where its inlet coolant enters the reactor vessel at the bottom, traversing up the sides to the top plenum, down-flow through an annular core, and exiting from the lower plenum (hot duct). This research provided NRC staff with (a) insights and knowledge about the control and protection systems for the NGNP and VHTR, (b) information on the technologies/approaches under consideration for use in the reactor and process heat applications, (c) guidelines for the design of highly integrated control rooms, (d) consideration for modeling of control and protection system designs for VHTR, and (e) input for developing the bases for possible new regulatory guidance to assist in the review of an NGNP license application. This NRC project also evaluated reactor and process heat application plant simulation models employed in the protection and control system designs for various plant operational modes and accidents, including providing information about the models themselves, and the appropriateness of the application of the models for control and protection system studies. A companion project for the NRC focused on the potential for new instrumentation that would be unique to modular HTGRs, as compared to light-water reactors (LWRs), due to both the higher temperature ranges and the inherent safety features.

Dynamic simulation and control studies of CPR1000 reactor core with advanced MSHIM control strategy

Traditional differential protection systems are applied on large power transformers using current transformers (CTs). However, because of high secondary currents (often exceeding 100 kA RMS) differential protection systems for electric arc furnace (EAF) transformers have not been applied in the past due to the lack of commercially available CTs. This paper will present differential protection systems that have been in use for many years using Rogowski Coil (RC) current sensors. These protection systems use high precision printed circuit board (PCB) Rogowski coil (RC) current sensors. The paper reviews the characteristics, designs, and application of these RC sensors for advanced protection, control, and metering systems with new multifunction relays. The paper compares performance characteristics of new solutions based on RC sensors with the conventional differential protection systems based on CTs, demonstrating that the new systems do not have the limitations of conventional technology. Operating experience from several site applications will be included.

The development of technology is expected to help humans in quality of life. The industrial world is making preparations for industrial revolution 4.0 which is designed to integrate the online world with production lines in industrial processes. All production processes in the 4.0 era and running with the internet as support. The internet has become one of the human's main needs. At present, the development of the internet has not yet developed with the development of protection and control systems in the electricity sector. A breakthrough is needed to create the necessary protection systems and also control the load. A Smart Plug is a breakthrough that can accommodate this. Relays available on Smart Plugs can be used as protection and control devices on household electrical appliances. To read current and load, the current sensor (ZHT 03) and voltage sensor (ZMPT101B) are used. All sensor and relay data is performed by Arduino Nano. Whereas NodeMCU 12-E is used to connect the Smart Plug with the web and database. Smart Plug test results with the web site show that Smart Plug can work well on protection and control systems. This is evidenced by the interrupted current flowing at the load, the load compilation current is more than the value of the current that has been determined as the set point. While the control system can also work optimally. Relays can be received according to orders given from the website.

Development of a digital reactor control and protection system

An approach to automating the technological process of obtaining bentonite-containing ion-exchange bipolar membranes is considered. The structures of automated systems are given, both with the use of local automation tools, and with the use of industrial controllers and workstations. The advantages and disadvantages of each of the structures are described. A two-level control system with the use of sensors, actuators, and an industrial controller at the lower level and a workstation at the upper level is suggested. The scheme of the complex of technical means is implemented. The information model of the upper level software of the control system taking into account the peculiarities of the technological process is developed. The data flow diagram is described and functioning principles of the upper level software are proposed. A software module, that is designed both to calculate control actions for the lower control level and to simulate periodic laboratory bipolar electrodialysis of a sodium sulfate solution with experimental bentonite-containing bipolar membranes to produce acid and alkali, has been developed in C++. During the operation of the software module, it is possible to trace the dependence of technological parameters of electrodialysis (ion flux, current efficiency, energy costs for the production of the target product) on the type of bentonite modifier used (alkyldimethylbenzylammonium chloride (surfactant) and stearic acid) and its quantity in membranes (1, 2, 3% wt.) at different current densities. The software module can be used in existing industries within the framework of functioning process control systems in order to optimize operating parameters during control of electrodialysis processe.

This paper describes an attempt to develop an automatic unmanned aerial vehicle (UAV) control system for emergency rescue and investigation. A cascade classifier system using Haar-like features for object recognition from a free viewpoint is also presented. Conventional emergency rescue systems have a shortcoming in terms of their performance. Thus, we introduce an automatic UAV control system in order to overcome the shortcoming of conventional emergency rescue systems in an emergency situation. The proposed system involves two processing stages. One involves a capturing and recognition of target objects, and the other involves controling the UAV using digital intelligence. Object detection in many types of images as well as real-time simulation methods continue to be one of the most common techniques for information processing and applications. The fundamental concepts of the proposed system and some experimental results obtained by using related processing techniques are also described.

The application of a Wide Area Monitoring Protection and Control (WAMPAC) system in a 110 kV local area distribution network (six 110 kV substations) is presented in this paper. The WAMPAC system consists of a central unit, and a local unit at each of the six 110 kV substations. It integrates the functions of monitoring, protection and control in the system. The protection function includes feeder protection, transformer protection, bus bar protection and CB fail protection. The control function includes synch check, auto-reclose, standby supply restoration, load shedding and generations tripping. The local area distribution network has embedded generations in it. If it is islanded, the system can shed the load or trip excess generations to keep the frequency near 50 Hz to meet the synch check criteria, so that the CB of the standby supply can be auto-closed and grid supply can be restored to the islanded area quickly.

The present paper describes the development of a 100kN hydraulic actuated press to perform aluminum stamping operations as well as mechanical tests. The press has two hydraulic servomechanisms: a hydraulic cylinder, driven by a servo-solenoid flow control valve, to support the punch tool; a hydraulic cylinder, where the chamber pressure is controlled by a servo-solenoid pressure control valve, to support the operations of loading and unloading of the press blank holder. A real time DSP based control card form dSPACE, which is directly programmed by the Matlab/Simulink environment, is used to implement the control and monitoring tasks and to perform data acquisition. The cylinders piston positions and chambers pressures are acquired with two optical scales and with analogue pressure sensors, respectively. The software setup allows the implementation of a hybrid controller (force + position) for the punch in such a way that it will be easy to switch between position and/or force control. A computer vision system is also integrated with the press control system in order to measure experimental data based on video images. An experiment to automatically measure the springback angle on an aluminum stamping operation is used, as an example, to show the functionality of the overall control and instrumentation systems.

The experience in the installation of modern digital systems for controlling converter units at the Vyborg converter substation on the basis of advanced microprocessor devices is considered. It is shown that debugging of a control and protection system on mathematical and physical models does not guarantee optimum control of actual converter devices. Examples of advancing the control and protection system are described, the necessity for which has become obvious in tests of actual equipment. Comparison of oscillograms of processes before optimization of the control system and after its optimization and adjustment shows that the digital control system makes it possible to improve substantially the algorithms of control and protection in the short term and without changing the hardware component.

Methods from learning theory are used in the state space of linear dynamical and control systems in order to estimate relevant matrices and some relevant quantities such as the topological entropy. An application to stabilization via algebraic Riccati equations is included by viewing a control system as an autonomous system in an extended space of states and control inputs. Kernel methods are the main techniques used in this paper and the approach is illustrated via a series of numerical examples. The advantage of using kernel methods is that they allow to perform function approximation from data and, as illustrated in this paper, allow to approximate linear discrete-time autonomous and control systems from data.

SummaryBased on tensor space, a new performance assessment approach is proposed for switched control systems in this paper. Switched control system is widely existing in industrial processes, especially in safety‐important processes where the systems controlled may be switched by protection logic during accident. Clearly, bad performance of control and protection strategies will eventually drive the system to a dangerous condition. To treat this problem, one may set up a performance assessment procedure for the switched control systems using multiple model method, where performance is evaluated through assessment of every individual submodel of the switched system. Obviously, this approach ignores interaction nature between control algorithm and protection strategy. The proposed method can capture the interaction nature of control and protection systems. In the tensor space, the interacting relation of control and protection systems can be synthetically represented by adding the logical switching space. Specifically, the tensor space modeling representation for switched systems has been developed, which can actually model the high coupling interaction of control and protection systems. The data‐driven tensor space algorithm based on higher‐order singular value decomposition has also been developed to assess the performance of switched control systems. By using orthogonal projection in tensor space extended from the matrix space, prediction error approach has been employed to obtain the optimal prediction error variance being as the control performance benchmark for performance assessment. Finally, numerical simulation examples are presented to illustrate the rationality and effectiveness of tensor space approach by comparing with the multiple model approach. Copyright © 2015 John Wiley & Sons, Ltd.

An AC generator is an important component in producing an electric power and so it requires highly reliable protection relays to minimize the possibility of demage occurring under fault conditions. It is a need for research of digital generator protection system(DGPS) for the next-generation ECMS and an efficient operation of protection control system in power station. However, most of protection and control system used in power plants have been still imported as turn-key and operated in domestic. This may cause the lack of the correct understanding on the protection systems and methods, and thus have difficulties in optimal operation. In this paper, presented ratio differential relaying(RDR) is main protective element in generator protection IED. The fault detection technique, operation zone and setting value of the RDR were studied and, compared with two of the fault detection algorithm. For evaluation performance of the RDR, the data obtained from ATPDraw5.7p4 modeling was used. The proposed methods are shown to be able to rapidly identify internal fault and did not operate a miss-operation for all the external fault.<BR>

This paper introduces a technique for assessing the reliability of protection and control systems using reliability models and event tree analysis. This technique allows a quantitative reliability assessment to be made, which can then be used to determine the effect of integrating different protection and control functions into a single unit. The term reliability when applied to protection system failure can be considered in terms of dependability and security. Dependability is defined as the probability that the protection operates satisfactorily when required, i.e. it does not fail to trip. Security is defined as the probability that the protection does not operate when not required to do so, i.e. it does not produce unwanted trips. Dependability results are given in this paper for feeder protection schemes based on differential protection, distance protection and combined differential and distance protection. The effect on the dependability of these schemes of including a separate and an integral intertrip unit is also considered. The former is housed in its own hardware, and the latter is integrated into the differential protection. Both intertrip units can be activated by either protection.

Power system protection is one important work which relate to security and stability of the power system. Power system relay protection is a very important part of power system and it relates to the power system security and stability. The time for fault reaction of power system protection determines the reliability of system protection and sensitivity. This paper mainly for the malfunctions of power system, we used the techniques of big data to reduce the size of the power network. We used the distributed computation and parallel computing to calculate fault calculation, topology analysis and setting calculation, which can shorten the operation time of protection equipment. At the same time, it also can improve the quality of the power and it can reduce the time harming the equipment and ensure the stable operation of the system.