Good practices of maintenance optimization in nuclear power field need to be effectively consolidated and inherited,and maintenance optimization can provide technology support to create a long-term reliable and econom...Good practices of maintenance optimization in nuclear power field need to be effectively consolidated and inherited,and maintenance optimization can provide technology support to create a long-term reliable and economic operation for nuclear power plants( NPPs) especially for a large number of nuclear powers under construction. Based on the development and application of maintenance template in developed countries,and combining with reliability-centered maintenance( RCM) analysis results and maintenance experience data over the past ten years in domestic NPPs, the development process of maintenance template was presented for Chinese pressurized water reactor( PWR) NPP,and the application of maintenance template to maintenance program development and maintenance optimization combined with cases were demonstrated. A shortcut was provided for improving the efficiency of maintenance optimization in domestic PWR NPP,and help to realize a safe,reliable,and economic operation for domestic NPPs.展开更多
This paper presents a novel method to solve old problem of water level control system of pressurized water reactor (PWR) steam generator (SG) of nuclear power plant (NPP) .The level control system of SG plays an impo...This paper presents a novel method to solve old problem of water level control system of pressurized water reactor (PWR) steam generator (SG) of nuclear power plant (NPP) .The level control system of SG plays an important role which effects the reliablity,safty,cost of SG and its mathematical models have been solved.A model of the conventional controller is presented and the existing problems are discussed. A novel rule based realtime control technique is designed with a computerized water level control (CWLC) system for SG of PWR NPP.The performance of this is evaluated for full power reactor operating conditions by applying different transient conditions of SG′s data of Qinshan Nuclear Power Plant (QNPP).展开更多
After the Fukushima disaster, interest in the evaluation of severe accidents in nuclear power plants and off-site consequences has significantly increased. Because experimental studies are difficult to conduct, comput...After the Fukushima disaster, interest in the evaluation of severe accidents in nuclear power plants and off-site consequences has significantly increased. Because experimental studies are difficult to conduct, computational methods play a substantial role in accident analysis. In this study, a severe accident in the Bushehr pressurized water reactor power plant caused by a station blackout with a total loss of alternating current power supply has been evaluated. This analysis presents the in-core damage of fuel rods and the release of fission products as well as the thermal hydraulic response of the station components during the loss of active emergency cooling systems. In this manner, a perfect model of the Bushehr nuclear power plant using the MELCOR code is prepared. The accident progression is simulated, and the thermal responses of the fuels and hydraulic components are presented. It is shown that, without operator intervention, steam generators will become dry in approximately 3000 s, and the heat sink of the reactor will be lost. The simulation results show that at approximately 8600 s, the upper parts of the core start melting. This model calculates the shortest available time for accident prevention and proves that the time available is sufficient for operator manual action to prevent a nuclear disaster.展开更多
This article proposes to associate a Deuterium-Deuterium (D-D) fusion reactor with a PWR (fission Pressurized Water Reactor) in a hybrid reactor. Even if the mechanical gain (Q factor) of the D-D fusion reactor is bel...This article proposes to associate a Deuterium-Deuterium (D-D) fusion reactor with a PWR (fission Pressurized Water Reactor) in a hybrid reactor. Even if the mechanical gain (Q factor) of the D-D fusion reactor is below the unity and consequently consumes more energy than it supplies, due to the high energy amplification factor of the PWR fission reactor, the global yield is widely superior to 1. As the energy supplied by the fusion reactor is relatively low and as the neutrons supplied are mainly issued from D-D fusions (at 2.45 MeV), the problems of heat flux and neutrons damage connected with materials, as with D-T fusion reactors are reduced. Of course, there is no need to produce Tritium with this D-D fusion reactor. This type of reactor is able to incinerate any mixture of natural Uranium, natural Thorium and depleted Uranium (waste issued from enrichment plants), with natural Thorium being the best choice. No enriched fuel is needed. So, this type of reactor could constitute a source of energy for several thousands of years because it is about 90 more efficient than a standard fission reactor, such as a PWR or a Candu one, by extracting almost completely the energy from the fertile materials U238 and Th232. For the fission part, PWR technology is mature. For the fusion part, it is based on a reasonable hypothesis done on present Stellarators projects. The working of this reactor is continuous, 24 hours a day. In this paper, it will be targeted a reactor able to provide net electric power of about 1400 MWe, as a big fission power plant.展开更多
Qinshan Phase Ⅲ(PHWR)Nuclear Power Plant,the first commercial heavy water reactor nuclear power plant in China,was the biggest trade project performed between the governments of China and Canada.As the owner,the Thir...Qinshan Phase Ⅲ(PHWR)Nuclear Power Plant,the first commercial heavy water reactor nuclear power plant in China,was the biggest trade project performed between the governments of China and Canada.As the owner,the Third Qinshan Nuclear Power Company(TQNPC)persisted in independent innovation management during the project construction,commissioning and self-dependent operation,efficiently realizing the three controls of the project,i.e.quality control,schedule control and investment control,and persisted in technical improvement on the basis of digestion and absorption of CANDU-6 technology to improve the unit safety and reliability.The project construction practice has helped China's nuclear power project management to becomeprogrammed,computerized,standardized and internationalized management from the existing basis.After completion of the project,with unit safe and steady operation as the prerequisite,TQNPC performed several technical modifications and innovations to continuously improve the unit performance.In the area of staff development,TQNPC paid much attention to cultivation of corporate culture,strengthed staff training and built up a good circulating mechanism with staff training and project construction promoting each other.Further to "Zero Breakthrough" and a new step forward of locolization successfully realized in Qinshan Nuclear Power Plant and Nuclear Power Qinshan Joint Venture Company,the improvement and developemnt of nuclear power project management level in Qinshan Phase Ⅲ(PHWR)Nuclear Power Plant provided reference for promotion of nuclear power development in China and standardized management of introducing large imported project.展开更多
Reactor pressure vessel (RPV), the only key component that can not be replaced in nuclear power plants (NPPs), is the main barrier against the radioactive leakage. The lifetime of NPPs is dependent heavily on the life...Reactor pressure vessel (RPV), the only key component that can not be replaced in nuclear power plants (NPPs), is the main barrier against the radioactive leakage. The lifetime of NPPs is dependent heavily on the life of RPV, and thus, the aging and life research on a RPV is a key factor in determining the life extension of NPPs. The purpose of this paper is to introduce an aging and life management system for an operating RPV which can be used as a reference of the lifetime extension. In order to realize the objective, an aging and life management system was developed. It is an comprehensive knowledge management system that integrates decentralized information and serves as a valuable data center. Based on the storage and management of RPV state information and operation data, this system provides real-time monitoring of important operating parameters, evaluation of irradiation embrittlement, and RPV aging assessment. Therefore, it is anticipated that the developed system can be used as an efficient tool for aging and life estimation of RPV.展开更多
为研究核电厂接入电力系统后二者之间的相互影响,利用电力系统分析综合程序(power system analysis software package,PSASP)的用户自定义建模功能建立压水堆(pressurized water reactor,PWR)核电厂主要环节的数学模型。该模型将压水堆...为研究核电厂接入电力系统后二者之间的相互影响,利用电力系统分析综合程序(power system analysis software package,PSASP)的用户自定义建模功能建立压水堆(pressurized water reactor,PWR)核电厂主要环节的数学模型。该模型将压水堆核电厂动力部分作为发电机调速器,可与电力系统连接,计算核电厂与电力系统之间的动态过程。在PSASP中使用该模型计算核电机组的自稳定性、自调节性和接入单机无穷大系统的故障响应,验证了模型的正确性和适用性。此外,由于压水堆的负温度效应,核电机组可承受一定的外部干扰和功率阶跃。若电网故障切除迅速,核电厂与电力系统之间的相互影响很小。展开更多
核电机组(nuclear power plant,NPP)具有单机容量大、核安全要求高等特性,失磁故障会影响核电机组安全性。为研究核电机组失磁时的机网协调控制策略,建立了大型压水堆核电机组的发电机模型、汽轮机及其控制系统模型、反应堆堆芯控制系...核电机组(nuclear power plant,NPP)具有单机容量大、核安全要求高等特性,失磁故障会影响核电机组安全性。为研究核电机组失磁时的机网协调控制策略,建立了大型压水堆核电机组的发电机模型、汽轮机及其控制系统模型、反应堆堆芯控制系统模型、励磁系统模型及失磁故障数学模型,研究了核电机组在不同功率水平运行时的失磁动态响应特性及机理。结果表明:满载失磁对反应堆及热力系统冲击大,核电机组应可靠跳闸;低功率运行失磁时,核电机组可以短期内维持并网异步运行;核电机组发生失磁导致厂用电的可靠性和供电质量下降,应该采取相应措施提高厂用电的可靠性。展开更多
文摘Good practices of maintenance optimization in nuclear power field need to be effectively consolidated and inherited,and maintenance optimization can provide technology support to create a long-term reliable and economic operation for nuclear power plants( NPPs) especially for a large number of nuclear powers under construction. Based on the development and application of maintenance template in developed countries,and combining with reliability-centered maintenance( RCM) analysis results and maintenance experience data over the past ten years in domestic NPPs, the development process of maintenance template was presented for Chinese pressurized water reactor( PWR) NPP,and the application of maintenance template to maintenance program development and maintenance optimization combined with cases were demonstrated. A shortcut was provided for improving the efficiency of maintenance optimization in domestic PWR NPP,and help to realize a safe,reliable,and economic operation for domestic NPPs.
文摘This paper presents a novel method to solve old problem of water level control system of pressurized water reactor (PWR) steam generator (SG) of nuclear power plant (NPP) .The level control system of SG plays an important role which effects the reliablity,safty,cost of SG and its mathematical models have been solved.A model of the conventional controller is presented and the existing problems are discussed. A novel rule based realtime control technique is designed with a computerized water level control (CWLC) system for SG of PWR NPP.The performance of this is evaluated for full power reactor operating conditions by applying different transient conditions of SG′s data of Qinshan Nuclear Power Plant (QNPP).
基金indebted to Shahid Beheshti University G. C. for partial support of this work
文摘After the Fukushima disaster, interest in the evaluation of severe accidents in nuclear power plants and off-site consequences has significantly increased. Because experimental studies are difficult to conduct, computational methods play a substantial role in accident analysis. In this study, a severe accident in the Bushehr pressurized water reactor power plant caused by a station blackout with a total loss of alternating current power supply has been evaluated. This analysis presents the in-core damage of fuel rods and the release of fission products as well as the thermal hydraulic response of the station components during the loss of active emergency cooling systems. In this manner, a perfect model of the Bushehr nuclear power plant using the MELCOR code is prepared. The accident progression is simulated, and the thermal responses of the fuels and hydraulic components are presented. It is shown that, without operator intervention, steam generators will become dry in approximately 3000 s, and the heat sink of the reactor will be lost. The simulation results show that at approximately 8600 s, the upper parts of the core start melting. This model calculates the shortest available time for accident prevention and proves that the time available is sufficient for operator manual action to prevent a nuclear disaster.
文摘This article proposes to associate a Deuterium-Deuterium (D-D) fusion reactor with a PWR (fission Pressurized Water Reactor) in a hybrid reactor. Even if the mechanical gain (Q factor) of the D-D fusion reactor is below the unity and consequently consumes more energy than it supplies, due to the high energy amplification factor of the PWR fission reactor, the global yield is widely superior to 1. As the energy supplied by the fusion reactor is relatively low and as the neutrons supplied are mainly issued from D-D fusions (at 2.45 MeV), the problems of heat flux and neutrons damage connected with materials, as with D-T fusion reactors are reduced. Of course, there is no need to produce Tritium with this D-D fusion reactor. This type of reactor is able to incinerate any mixture of natural Uranium, natural Thorium and depleted Uranium (waste issued from enrichment plants), with natural Thorium being the best choice. No enriched fuel is needed. So, this type of reactor could constitute a source of energy for several thousands of years because it is about 90 more efficient than a standard fission reactor, such as a PWR or a Candu one, by extracting almost completely the energy from the fertile materials U238 and Th232. For the fission part, PWR technology is mature. For the fusion part, it is based on a reasonable hypothesis done on present Stellarators projects. The working of this reactor is continuous, 24 hours a day. In this paper, it will be targeted a reactor able to provide net electric power of about 1400 MWe, as a big fission power plant.
文摘Qinshan Phase Ⅲ(PHWR)Nuclear Power Plant,the first commercial heavy water reactor nuclear power plant in China,was the biggest trade project performed between the governments of China and Canada.As the owner,the Third Qinshan Nuclear Power Company(TQNPC)persisted in independent innovation management during the project construction,commissioning and self-dependent operation,efficiently realizing the three controls of the project,i.e.quality control,schedule control and investment control,and persisted in technical improvement on the basis of digestion and absorption of CANDU-6 technology to improve the unit safety and reliability.The project construction practice has helped China's nuclear power project management to becomeprogrammed,computerized,standardized and internationalized management from the existing basis.After completion of the project,with unit safe and steady operation as the prerequisite,TQNPC performed several technical modifications and innovations to continuously improve the unit performance.In the area of staff development,TQNPC paid much attention to cultivation of corporate culture,strengthed staff training and built up a good circulating mechanism with staff training and project construction promoting each other.Further to "Zero Breakthrough" and a new step forward of locolization successfully realized in Qinshan Nuclear Power Plant and Nuclear Power Qinshan Joint Venture Company,the improvement and developemnt of nuclear power project management level in Qinshan Phase Ⅲ(PHWR)Nuclear Power Plant provided reference for promotion of nuclear power development in China and standardized management of introducing large imported project.
文摘Reactor pressure vessel (RPV), the only key component that can not be replaced in nuclear power plants (NPPs), is the main barrier against the radioactive leakage. The lifetime of NPPs is dependent heavily on the life of RPV, and thus, the aging and life research on a RPV is a key factor in determining the life extension of NPPs. The purpose of this paper is to introduce an aging and life management system for an operating RPV which can be used as a reference of the lifetime extension. In order to realize the objective, an aging and life management system was developed. It is an comprehensive knowledge management system that integrates decentralized information and serves as a valuable data center. Based on the storage and management of RPV state information and operation data, this system provides real-time monitoring of important operating parameters, evaluation of irradiation embrittlement, and RPV aging assessment. Therefore, it is anticipated that the developed system can be used as an efficient tool for aging and life estimation of RPV.
文摘为研究核电厂接入电力系统后二者之间的相互影响,利用电力系统分析综合程序(power system analysis software package,PSASP)的用户自定义建模功能建立压水堆(pressurized water reactor,PWR)核电厂主要环节的数学模型。该模型将压水堆核电厂动力部分作为发电机调速器,可与电力系统连接,计算核电厂与电力系统之间的动态过程。在PSASP中使用该模型计算核电机组的自稳定性、自调节性和接入单机无穷大系统的故障响应,验证了模型的正确性和适用性。此外,由于压水堆的负温度效应,核电机组可承受一定的外部干扰和功率阶跃。若电网故障切除迅速,核电厂与电力系统之间的相互影响很小。
文摘核电机组(nuclear power plant,NPP)具有单机容量大、核安全要求高等特性,失磁故障会影响核电机组安全性。为研究核电机组失磁时的机网协调控制策略,建立了大型压水堆核电机组的发电机模型、汽轮机及其控制系统模型、反应堆堆芯控制系统模型、励磁系统模型及失磁故障数学模型,研究了核电机组在不同功率水平运行时的失磁动态响应特性及机理。结果表明:满载失磁对反应堆及热力系统冲击大,核电机组应可靠跳闸;低功率运行失磁时,核电机组可以短期内维持并网异步运行;核电机组发生失磁导致厂用电的可靠性和供电质量下降,应该采取相应措施提高厂用电的可靠性。
