Laijun Chen

Distributed economic automatic generation control: A game theoretic perspective

Automatic generation control (AGC) is regularly used to maintain frequency stability and quality in multi-area power system. As each of control areas intend to achieve the best economy during AGC regulation, a concept of optimally economic AGC in a distributed manner arises and is required to investigate. Game theory provides a natural framework for such a kind of problems. Since different control areas may compete or cooperate with each other, cooperative and non-cooperative games are studied in this paper, and are further distinguished with different types of area control errors (ACEs). Two fully distributed, optimally economic AGC strategies for the two game models are proposed with a proof of convergence. Then the incentives and efficiency of cooperation in different control areas are discussed. Finally, the rudimentary IEEE 9-bus, 3-areas power system is used to verify the proposed methodology.

Thermal-wind-storage joint operation of power system considering pumped storage and distributed compressed air energy storage

To realize the efficient accommodation and utilization of large-scale wind power, a thermal-wind-storage joint operation framework considering pumped storage (PS) and compressed air energy storage (CAES) is proposed in this paper. Dynamic operating characteristics are transformed into operating constraints and added into the ideal model of PS. A new CAES concept based on an ongoing project is presented. A practicable model based on this concept is established, in which dynamic efficiency of it is well considered. Through case study, the effectiveness of the proposed framework is proved. Discussion on the optimal deployment proportion of PS and CAES in terms of daily operation of power system and their optimal energy schedule tactics is also analyzed in this paper.

Robust small-signal stability region of power systems considering uncertain wind generation

The integration of large-scale wind generation has brought great challenges to the small-signal stability analysis of power systems, due to the output uncertainty of wind farms. To solve this problem, this paper extends the conventional concept of small-signal stability region (SSSR) to a concept of robust small-signal stability region (R-SSSR), which is capable of dealing with the effects of uncertain injections on the SSSR. First, the conventional theory of small-signal stability region and the stability radius theory are introduced. Then the definition of R-SSSR as well as the algorithm for computing the boundary of R-SSSR is described. A WSCC 3-generator-9-bus system with wind generation is utilized to validate the new concept of R-SSSR. The results demonstrate that R-SSSR could be a promising tool for the small-signal stability analysis on power systems with large-scale uncertain wind generation.

Integrating an Improved Averaged Model for PWM Converters Into EMTP

To accelerate electromagnetic-transient (EMT) simulations of pulsewidth-modulated (PWM) converters, a novel algorithm is proposed in this letter, which integrates an improved averaged model of PWM converters into the Electromagnetic Transients Program. The effectiveness of the proposed algorithm is verified by a single-phase dc-ac converter system.

Economic Dispatch of an Integrated Heat-Power Energy Distribution System with a Concentrating Solar Power Energy Hub

AbstractUsing multiple energy resources greatly enhances system operating flexibility and efficiency. An energy hub is a vital facility, producing, converting, and storing energy in different forms...

A fine-grained parallel EMTP algorithm compatible to graphic processing units

Electromagnetic transient (EMT) simulations become more time-consuming with the increasing complexity of power systems. Thus, it is necessary to exploit the feasibility of accelerated EMT simulations taking advantage of latest heterogeneous parallel computing technologies. A fine-grained parallel EMT algorithm is proposed in this work, which makes full uses of the advanced Single-Instruction-Multi-Threads (SIMT) and shared memory parallelisms supported by Graphic Processing Units (GPUs). Moreover, time-cost models of the proposed algorithm are also presented, which is valuable for optimizing the run-time configurations and enhancing the efficiency of the parallel simulations on GPUs. Test results of large-scale power systems not only verified the accuracy and efficiency of the proposed the algorithm and but also validated the time-cost models derived.

A general parameter configuration algorithm for associate discrete circuit switch model

Associated Discrete Circuit (ADC) based switch model with Fixed Admittance Matrix (FAM) is widely adopted in real-time power system electromagnetic transient (EMT) simulation. However, conflictions between simulation error minimization and oscillation suppression causes great difficulties on ADC parameters configuration for switches. A general parameter configuration algorithm to determine the equivalent parameters of ADC switch model is proposed in this work, which applies optimization method to balance the conflictions. Provided test results not only verified the accuracy of ADC switch model and but also validated the algorithm derived.

A parallel based real-time electromagnetic transient simulator for IPS

IPS has many special characteristics, such as using multi-phase, multi-frequency and hybrid AC/DC devices. As a result, existing electromagnetic transient simulators developed for power systems on land do not apply to IPS. This paper aims to build up a parallel based real-time electromagnetic transient simulator for IPS. A fast multi-switching process method for parallel electromagnetic transient simulations is coined to handle the tremendous switch events in IPS. To solve the difficulties brought by multi-phase machines in IPS, a multilevel hybrid parallel algorithm is forged through the combination of component level and network level parallelization. Based on the key techniques mentioned above, a parallel simulator is built up. Through sufficient testing to typical examples of IPS, the accuracy and high-efficiency of the simulator are proved.

A novel algorithm for parallel electromagnetic transient simulation of power systems with switching events

The electromagnetic transient simulation of power system with many switching events is very time-consuming due to the huge increment of computation caused by frequent changing system topologies. To speedup the parallel simulations of the power systems with switch events, a novel algorithm based on the Multi Area Thevenin Equivalent (MATE) and the flexible half-step interpolation method is proposed. Through runtime caching of the matrixes corresponding to the topology changes, the repeated matrix operations are eliminated for both the subsystem and coordinator sides, while the communication costs for the parallel simulations are also reduced significantly. Moreover, a parallel simulation platform is developed based on the multi-core computation environment and MPI functions. On this platform, the accuracy and efficiency of the proposed algorithm are verified by the real-time simulations of a power system containing four 3-phase rectifiers and three 5-phase PWM inverters.

A GPU-based parallel simulation platform for large-scale wind farm integration

Due to the energy crisis of the next fifty years, an increasing number of large-scale wind farms are integrating into power systems. Parallel simulation platforms are indispensable to evaluate the effects of wind farm integration. A GPU-based parallel simulation platform is constructed in this paper to test the feasibility of simulating integration systems on GPU. By adopting previous research work such as averaged model and improved EMTP algorithm, models and algorithm of the platform are firstly introduced. Then the hardware and software architecture of the platform are put forward, which combine CPU configuration and GPU computing. Finally, a wind farm with different numbers of DFIGs are used to test the performance of the platform. Results show that the platform has excellent accuracy, efficiency and scalability. The work of this paper proves the feasibility to simulate wind farm integrating dynamics adopting GPU and its potential to reach tremendous efficiency and scalability.