Bus Node Research Articles

Prospect Theoretic Study of Honeypot Defense Against Advanced Persistent Threats in Power Grid

As one of the most critical infrastructure, the power grid has been increasingly threatened by network attacks, especially advanced persistent threats (APTs). APT in the power grid is a continual and stealthy attack that analyzes the interaction between the cyber layer and the physical layer. The existing offensive and defensive processes for power grid using honeypots against APTs are modeled based on full rationality. Therefore, both the attacker and the defender make decisions to maximize their payoffs under full rationality. However, fully rational decisions made by end-users are not always conformed with the real cases, and prospect theory is a typical boundedly rational method to model these deviations. In this study, we propose a subjective APT-honeypot game model to study the offensive and defensive interactions between the attacker and the defender based on the prospect theory. In this model, we protect the power grid bus nodes by deploying honeypots, which consider both low- and high-interaction honeypot modes. We prove the existence of Bayesian-Nash equilibrium strategies in defense and attack strategies under bounded rationality. In addition, we used IEEE-30 Bus system to verify the proposed model in this paper. Experiment results show that bounded rationality affects strategy selection and reduces attacker’s payoffs.

Finite‐time composite control scheme for three‐phase four‐leg inverter under variable operating conditions

Three-phase four-leg inverters widely used in microgrid can effectively provide the power for the non-linear/unbalanced loads. Here, the non-linear composite controller is proposed for three-phase four-leg inverter system under d q 0 reference frame by integrating a higher order sliding mode observer and finite-time control technique. The observer adopts the soft sensing manner to feedforward compensate external disturbances caused by current variation of AC bus node, which relaxes some physical constraints. Meanwhile, the higher order sliding mode observer realises the decoupling of the inverter system, which paves the way for the construction of the non-smooth finite-time control law. Finally, the simulation results with PI comparison illustrate the feasibility of the proposed method for improving the robustness, stability, and rapid recovery capability of system.

Recognition of Branch Series Resonance Based on Port Equivalent Method

For the identification of series resonance in power system branches, the identification method of branch series resonance based on port equivalent method is proposed. First of all, a typical three-bus test system is used to analyze the series resonance of the branch. It is found that the branch series resonance can be identified by the port equivalent admittance formed between the bus node and the reference node. Then, by establishing the node port association matrix and using the node impedance matrix, the multi-port Thevenin equivalent impedance matrix is obtained, in other words, the equivalent admittance matrix of the port is formed, and the load branch of the node is eliminated, as well as the effect of the node load branch on the series resonance of the identification branch is eliminated. The algorithm effectively utilizes the node admittance matrix commonly used in power system. Finally, the feasibility and correctness of the three-bus system and IEEE9 network system are proved by simulation analysis. The validity of this novel formulation is confirmed through theoretical analysis and case studies.

IMPROVEMENT OF TRANSIENT STABILITY OF AUTONOMOUS POWER SYSTEM ON BASIS OF WIDE AREA CONTROL SYSTEM

Abstract: The coordinated generation and load control to increase transient stability level of oil- production enterprise autonomous power system with dominant motor load is studied in the paper. Mutual angle between voltage phasors at gas turbine plant bus and equivalent load node as well as slip difference of synchronous machines are used as input signals. It is shown that implementation of additional control allows to increase the level of transient stability by more than 40%. The combined coordination of power system stabilizer of synchronous generators and motors as well as gas turbine frequency control parameters is applied. The positive impact of power system stabilizer settings on post-accident conditions is proved by analysis of small signal stability.

A novel trust-based false data detection method for power systems under false data injection attacks

This paper proposes a novel trust-based false data detection method for power systems under false data injection attacks (FDIAs). In order to eliminate the interference posed by false data to the power system in the state estimation process, a trust model is first established to estimate the reliability of the system bus. Then an algorithm is proposed to update the bus trust value, when all the trust value of neighbor buses at one bus node are quite low, then this bus is diagnosed as a malicious node and the false data are detected. This method guarantees that the power systems can estimate the state accurately against FDIAs based on the trust of bus. The simulations on the benchmark IEEE 14-bus, IEEE 30-bus and IEEE 57-bus test systems are used to demonstrate the feasibility and effectiveness of proposed algorithm.

Detection of False Data Injection Attacks in Smart Grid Utilizing ELM-Based OCON Framework

False data injection (FDI) attacks, as a new class of cyberattacks, bring a severe threat to the security and reliable operation of the smart grid by damaging the state estimation of the power system. To address this issue, an extreme learning machine (ELM)-based one-class-one-network (OCON) framework is proposed for detecting the FDI attacks in this paper. Under this framework, to effectively detect bus-based FDI attacks and identify the bus node being attacked, the subnets of state identification layer in OCON adopt the ELM algorithm to accurately divide the false data and the normal data. After that, a global layer is employed to analyze whether the bus node associated with its corresponding subnet is attacked by false data utilizing the results from the state identification layer. Finally, in order to improve the resilience of the power system, a prediction recovery strategy is proposed to remedy the detected false data by exploiting the spatial correlation of power data. The proposed framework is tested on the IEEE 14 bus system using real load data from New York independent system operator. The simulation results demonstrate that the proposed framework not only accurately recognizes the multiple bus nodes under the FDI attacks but also efficiently recovers the data injected by false data.

A Bus-Oriented Mobile FCNs Infrastructure and Intra-Cluster BSM Transmission Mechanism

With the concept of edge computing being put forward, the edge node should play an important role in resource allocation and local computation. However, there are two basic problems to confront in this arena: the performance of basic safety message (BSM) exchange and the frequency of service migration, both of which are related to the vehicle’s mobility feature. To decrease the frequency of service migration and enhance the efficiency of the BSM exchange, in this paper, a bus-oriented mobile fog computing nodes infrastructure is proposed, while a mobile similarity-based clustering method is given. In the proposed method, the bus node, which is considered as a fog-computing node (FCN), is used as a sink node, which fulfills communication resource allocation and convergence computing tasks. MATLAB is used to simulate the path loss feature, while a network simulator (NS-3) is employed to investigate the performance of the proposed scheme. The simulation results show that the proposed scheme significantly decreases the frequency of service migration and perform high communication efficiency for intra-cluster BSMs exchange.

Design and Experiment of Multi-information Collection System for Grain Combine Harvesters

To obtain the online multi-information of the machine performance, working condition and other parameters for gain combine harvester, a controller area network (CAN bus) based distributed data collection, transmission and processing system was constructed and tested. In this system a series of sensors was designed or optimized, such as attitude sensors for sensing the rise and fall of header, torque sensors and revolution speed sensors for measuring the power output, torque and rotational speed, GPS module for detecting operating speed and location. And with ARM embedded processor, a universal information acquisition node was designed based on CAN bus to collect and process the datas from system-wide sensors. Furthermore, with CAN network, 3G networks and RS232-based telematics data exchange gateway, the telematics data exchange gateway was built for asynchronous communication with CAN bus node, telematics monitor, and remote database server. In addition, a order-driven synchronous data acquisition strategy was prosposed for the purpose of improving the synchronicity of combine harvester multi-information for a period of time. This system was proved to be stable, reliable, strong anti-interference and realized the object of synchronous acquisition of machine performance, working condition, power consumption and other information, and transmission frequency can reach 5KHz under 10 nodes and frame loss rate (FLR) was lower than 1%. The use of this system will be an effective support for multi-information collection of gain combine harvester.

PMU Placement for Line Outage Identification via Multinomial Logistic Regression

We consider the problem of identifying a single line outage in a power grid by using data from phasor measurement units (PMUs). When a line outage occurs, the voltage phasor of each bus node changes in response to the change in network topology. Each individual line outage has a distinctive signature, and a multinomial logistic regression classifier can be trained to distinguish between these signatures reliably. We consider first the ideal case in which PMUs are attached to every bus. We then describe techniques from regularized optimization for placing PMUs selectively on a subset of buses, with the subset being chosen to allow discrimination between as many outage events as possible. Experimental results with synthetic 24-h demand profile data generated for IEEE 14-, 30-, 57-, and 118-bus systems are presented.

Mathematical Model for Automatic Short-Circuit Calculation Based On Incidence Matrix in Coal Mine High-Voltage Grid

The mathematical model of automatic short-circuit calculation is proposed, that is directly used in coal mine high-voltage grid. The model combinates incidence matrix with short-circuit calculation in mine high-voltage grid. According to the connectivity of single-direction graph, the model describes the power supply relation matrix of branches node in coal mine high-voltage grid by the incidence matrix of bus node and branch node. The short-circuit calculation of all short-circuit points is achieved, according to the short-circuit matrix of three-phase and two-phase short-circuit current in all short circuit points given by the model. The analysis results show that the model can realize automatic short-circuit calculation accurately in coal mine high-voltage grid, and it provides a foundation for studying the performance of automatic short-circuit calculation and adaptive setting calculation of multiple fault operation mode.

Centralized Charging Strategy and Scheduling Algorithm for Electric Vehicles Under a Battery Swapping Scenario

Centralized charging of electric vehicles (EVs) based on battery swapping is a promising strategy for their large-scale utilization in power systems. The most outstanding feature of this strategy is that EV batteries can be replaced within a short time and can be charged during off-peak periods or on low electric price and scheduled in any battery swap station. This paper proposes a novel centralized charging strategy of EVs under the battery swapping scenario by considering optimal charging priority and charging location (station or bus node in a power system) based on spot electric price. In this strategy, a population-based heuristic approach is designed to minimize total charging cost, as well as to reduce power loss and voltage deviation of power networks. We introduce a dynamic crossover and adaptive mutation strategy into a hybrid algorithm of particle swarm optimization and genetic algorithm. The resulting algorithm and several others are executed on an IEEE 30-bus test system, and the results suggest that the proposed one is effective and promising for optimal EV centralized charging.

Wireless sensing of substation parameters for remote monitoring and analysis

This paper aimed to monitor the different bus parameters in a substation from a centralized control room with the help of Zigbee enabled wireless sensor network (WSN). The parameters such as magnitude and phase angles of voltage and current, frequency, rate-of-change-of-frequency (ROCOF), active and reactive powers are measured using a state-of-the-art customized Zigbee enabled phasor measurement unit (ZPMU). The data from different ZPMUs at different bus nodes are acquired with the help of WSN system in order to have a centralized monitoring of different equipments load status. The coordination among different parameters for different buses and/or equipment is done from a centralized control room within the substation or plant with the help of substation management software and Zigbee networking. The data thus collected are utilized to study the power flow status of the different buses on real time basis and are stored within a server based database for future analysis purposes.

Research on Wireless MIL-STD-1553B Bus Based on Infrared Technology

Infrared technology has the benefits of low mass, size, power and cost, minimum electromagnetic interference (EMI), efficient and reliable data transfer, which is suitable for the communications in small spacecrafts. A wireless data bus system based on infrared technology for intra-spacecraft communication is proposed in this paper. The bus protocol is following the traditional MIL-STD-1553B, while the 1553B bus transceivers, transformers and cables in the physical layer are replaced by infrared transceivers. Infrared transceivers shouldn’t affect the 1553B higher layers and the layout of the onboard equipment. So a wireless bus is designed via diffuse optical wireless links. This paper focuses on the implementation of an IR wireless 1553B bus system, including hardware design of the wireless bus nodes, logic design of the 1553B bus protocol on FPGA, and the signal formatting between 1553B signals and IR signals. A radiation-hard application specific integrated circuit (ASIC) chip is designed for the application of the wireless 1553B bus in future space missions. Experimental results prove the reliability and feasibility of the wireless data bus system. Finally, some challenges and problems in space applications are put forward.

A NEW Data Acquisition Method to CAN and 1553B Armored Vehicle Buses

There are 5 kinds of bus networks on armored vehicles. The current vehicle serial bus test equipments are not universal to different kind bus system. And can just complete the performance test to DLL, cannot test the buss physical electrical performance. This paper brings forward a new data acquisition method to universal buses based on software decoding, The data acquisition experiments to CAN and 1553B bus with their corresponding bus nodes have been completed.

Research on Data Acquisition Technology to 1553B Based on Physical Sampling Data and Software Decoding

The performance of 1553B bus network is very important to running safety of new generation armored vehicle. Because the current 1553B bus test equipment can only complete the translation performance test to DLL and cannot test the bus’ physical electrical performance, this paper brings forward a data acquisition technology to 1553B based on Physical Sampling Data and Decoding Software, fulfills the data acquisition experiment to 1553B with its bus nodes, and validates the feasibility of this technology.

Modeling and Analysis of Voltage and Power Control Devices in Current Injections Load Flow Method

This article presents a developed method to improve the representation of a voltage-controlled bus in the current injection load flow method. This improvement is based on a hybrid current and power mismatches formulation, where the load bus equations are represented by current mismatches and voltage-controlled buses bus equations are based on power mismatches. In this method, the advantages of the Newton–Raphson method and current injection mismatches method are collected. The total number of equations is reduced, where only one equation is required for each voltage-controlled bus. This article also describes direct modeling of voltage/power control devices in the developed load flow method. The static synchronous compensator can be represented as a voltage-controlled bus node in terms of power mismatch. The static series synchronous compensator and unified power flow controller are modeled by series impedance and two current injections at the corresponding nodes. In the case of unified power flow controller, additional power injection is included at the sending-end node to represent the voltage-controlled node. This modeling reduces the complexities of the computer program codes and enhances the reusability by avoiding the modifications in the Jacobian matrix. The IEEE data as well as systems from literature are used to validate the developed method and flexible AC transmission systems models.

Research on In-Vehicle FlexRay Bus Network Nodes

Network node designs of hardware system and software system based on in-vehicle FlexRay Bus were put forward. Structure and theory of node’s MCU, communication controller and Bus drive were analyzed. The simplest system of FlexRay Bus node was structured, and main files program, clock program, interruption program, and FlexRay Bus communication program were configured. The operation status of FlexRay Bus protocol was analyzed, and programs of receiving and transmitting data were designed. The experimental system based on MC9S12XF512 was established, and in development environment of CodeWarrior IDE, FlexRay Bus networks nodes communication was accomplished based on TDMA and FTDMA mechanism.

Research on CAN Bus of Pure Electric Vehicles Based on SAEJ1939

The use of CAN bus network on electric vehicles is of great significance, it can not only greatly reduce the costs of electric vehicles, but also increase the driving distance of electric vehicles. The stability of CAN bus load rate and CAN network communication rate plays a vital role to the CAN network，by studying and making use of SAEJ1939, this paper develops a vehicle network topology, then through calculating the bit rate of transfer time to calculate the load rate, combined with using the software named CANoe from the Vector company in Germany to analyse and simulate the sending cycle of each CAN bus node on pure electric vehicles. In this way,this paper analyses the reasonableness of CAN network design of the vehicle body. Finally this paper applies the on-site verification to prove the reliability of simulation results. This study is based on SAEJ1939 agreement CAN2.0B, did not make a study for CAN2.0A, so there are limitations, the findings may not apply to CAN2.0A.

Study and Design of CAN Bus Node Based on MC912D60A Microcontroller in Automobile

Controller Area Network (CAN) is a kind of serial communication network that supports the distributed control and the real time control. The CAN have high performances and high reliabilities. It can solve many problems of complex circuitry, wiring harness increasing, operation reliability reducing and the difficulty of fault maintain increasing while using CAN Bus technology in automobile. In this paper, the form of CAN bus and node design method based on MC912D60A single chip microcomputer were studied and introduced. At last, the hardware design principle diagrams and software flow charts were given.

Synchronization of Power Networks: Network Reduction and Effective Resistance

In transient stability studies in power networks two types of mathematical models are commonly used – the differential-algebraic structure-preserving model and the reduced dynamic model of interconnected swing equations. This paper analyzes the reduction process relating the two power network models. The reduced admittance matrix is obtained by a Schur complement of the topological network admittance matrix with respect to its bus nodes. We provide a detailed spectral, algebraic, and graph-theoretic analysis of this network reduction process, termed Kron reduction, with particular focus on the effective resistance. As an application of this analysis, we are able to state concise conditions relating synchronization in the considered structure-preserving power network model directly to the state, parameters, and topology of the underlying network. In particular, we provide a spectral condition based on the algebraic connectivity of the network and a second condition based on the effective resistance among generators.