Design of the flexible switching controller for small PWR core power control with the multi-model

Zeng, Wenjie,Jiang, Qingfeng,Du, Shangmian,Hui, Tianyu,Liu, Yinuo,Li, Sha Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.3

Small PWR can be used for power generation and heating. Considering that small PWR has the characteristics of flexible operating conditions and complex operating environment, the controller designed based on single power level is difficult to achieve the ideal control of small PWR in the whole range of core power range. To solve this problem, a flexible switching controller based on fuzzy controller and LQG/LTR controller is designed. Firstly, a core fuzzy multi-model suitable for full power range is established. Then, T-S fuzzy rules are designed to realize the flexible switching between fuzzy controller and LQG/LTR controller. Finally, based on the core power feedback principle, the core flexible switching control system of small PWR is established and simulated. The results show that the flexible switching controller can effectively control the core power of small PWR and the control effect has the advantages of both fuzzy controller and LQG/LTR controller.

Constrained Relay Node Deployment using an improved multi-objective Artificial Bee Colony in Wireless Sensor Networks

( Wenjie Yu ),( Xunbo Li ),( Xiang Li ),( Zhi Zeng ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.6

Wireless sensor networks (WSNs) have attracted lots of attention in recent years due to their potential for various applications. In this paper, we seek how to efficiently deploy relay nodes into traditional static WSNs with constrained locations, aiming to satisfy specific requirements of the industry, such as average energy consumption and average network reliability. This constrained relay node deployment problem (CRNDP) is known as NP-hard optimization problem in the literature. We consider addressing this multi-objective (MO) optimization problem with an improved Artificial Bee Colony (ABC) algorithm with a linear local search (MOABCLLS), which is an extension of an improved ABC and applies two strategies of MO optimization. In order to verify the effectiveness of the MOABCLLS, two versions of MO ABC, two additional standard genetic algorithms, NSGA-II and SPEA2, and two different MO trajectory algorithms are included for comparison. We employ these metaheuristics on a test data set obtained from the literature. For an in-depth analysis of the behavior of the MOABCLLS compared to traditional methodologies, a statistical procedure is utilized to analyze the results. After studying the results, it is concluded that constrained relay node deployment using the MOABCLLS outperforms the performance of the other algorithms, based on two MO quality metrics: hypervolume and coverage of two sets.

Pressure Contact Interconnection for High Reliability Medium Power Integrated Power Electronic Modules

Xu Yang,Wenjie Chen,Xiaoyu He,Xiangjun Zeng,Zhaoan Wang 전력전자학회 2009 JOURNAL OF POWER ELECTRONICS Vol.9 No.4

This paper presents a novel spring pressure contact interconnect technique for medium power integrated power electronics modules (IPEMs). The key technology of this interconnection is a spring which is made from Be-Cu alloy. By means of the string pressure contact, sufficient press-contact force and good electrical interconnection can be achieved. Another important advantage is that the spring exhibits excellent performance in enduring thermo-mechanical stress. In terms of manufacture procedure, it is also comparatively simple. A 4 ㎾ half-bridge power inverter module is fabricated to demonstrate the performance of the proposed pressure contact technique. Electrical, thermal and mechanical test results of the packaged device are reported. The results of both the simulation and experiment have proven that a good performance can be achieved by the proposed pressure contact technique for the medium power IPEMs.

Pressure Contact Interconnection for High Reliability Medium Power Integrated Power Electronic Modules

Yang, Xu,Chen, Wenjie,He, Xiaoyu,Zeng, Xiangjun,Wang, Zhaoan The Korean Institute of Power Electronics 2009 JOURNAL OF POWER ELECTRONICS Vol.9 No.4

This paper presents a novel spring pressure contact interconnect technique for medium power integrated power electronics modules (IPEMs). The key technology of this interconnection is a spring which is made from Be-Cu alloy. By means of the string pressure contact, sufficient press-contact force and good electrical interconnection can be achieved. Another important advantage is that the spring exhibits excellent performance in enduring thermo-mechanical stress. In terms of manufacture procedure, it is also comparatively simple. A 4 kW half-bridge power inverter module is fabricated to demonstrate the performance of the proposed pressure contact technique. Electrical, thermal and mechanical test results of the packaged device are reported. The results of both the simulation and experiment have proven that a good performance can be achieved by the proposed pressure contact technique for the medium power IPEMs.

Uncertainty quantification of once-through steam generator for nuclear steam supply system using latin hypercube sampling method

Lekang Chen,Chuqi Chen,Linna Wang,Wenjie Zeng,Zhifeng Li Korean Nuclear Society 2023 Nuclear Engineering and Technology Vol.55 No.7

To study the influence of parameter uncertainty in small pressurized water reactor (SPWR) once-through steam generator (OTSG), the nonlinear mathematical model of the SPWR is firstly established. Including the reactor core model, the OTSG model and the pressurizer model. Secondly, a control strategy that both the reactor core coolant average temperature and the secondary-side outlet pressure of the OTSG are constant is adopted. Then, the uncertainty quantification method is established based on Latin hypercube sampling and statistical method. On this basis, the quantitative platform for parameter uncertainty of the OTSG is developed. Finally, taking the uncertainty in primary-side flowrate of the OTSG as an example, the platform application work is carried out under the variable load in SPWR and step disturbance of secondary-side flowrate of the OTSG. The results show that the maximum uncertainty in the critical output parameters is acceptable for SPWR.

Uncertainty quantifi cation of the power control system of a small PWR with coolant temperature perturbation

Xiaoyu Li,Chuhao Li,Yang Hu,Yongqi Yu,Wenjie Zeng,Haibiao Wu 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.6

The coolant temperature feedback coefficient is an important parameter of reactor core power controlsystem. To study the coolant temperature feedback coefficient influence on the core power controlsystem of small PWR, the core power control system is built with the nonlinear model and fuzzy controltheory. Then, the uncertainty quantification method of reactor core parameters is established based onthe Latin hypercube sampling method and the Bootstrap method. Finally, under the conditions ofreactivity step perturbation and coolant inlet temperature step perturbation, uncertainty analysis for twocases is carried out. The result shows that with fuzzy controller and fuzzy PID controller, the uncertaintyof the coolant temperature feedback coefficient affects the core power control system, and the maximumuncertainties of core relative power, coolant temperature deviation, fuel temperature deviation and totalreactivity are acceptable

Neutronic Study of Utilization of Discrete Thorium-Uranium Fuel Pins in CANDU-6 Reactor

Nianbiao Deng,Tao Yu,Jinsen Xie,Zhenping Chen,Qin Xie,Pengcheng Zhao,Zijing Liu,Wenjie Zeng 한국원자력학회 2019 Nuclear Engineering and Technology Vol.51 No.2

Targeting at simulating the application of thorium-uranium (TU) fuel in the CANDU-6 reactor, this paperanalyzes the process using the code DRAGON/DONJON where the discrete TU fuel pins are applied in theCANDU-6 reactor under the time-average equilibrium refueling. The results show that the coolant voidreactivity of the assembly analyzed in this paper is lower than that of 37-element bundle cell withnatural uranium and 37-element bundle cell with mixed TU fuel pins; that the max time-averagechannel/bundle power of the core meets the limits - less than 6700kW/860 kW; that the fuel conversionratio is higher than that of the CANDU-6 reactor with natural uranium; and that the exit burnupincreases to 13400 MWd/tU. Thus, the simulation in this paper with the fuel in the 37-element bundlecell using discrete TU fuel pins can be considered to be applied in CANDU-6 reactor with adequatemodifications of the core structure and operating modes.