By integrating advanced digital technologies such as cloud computing and the Internet of Things in sensor measurement,information communication,and other fields,the digital DC distribution network can efficiently and ...By integrating advanced digital technologies such as cloud computing and the Internet of Things in sensor measurement,information communication,and other fields,the digital DC distribution network can efficiently and reliably access DistributedGenerator(DG)and Energy Storage Systems(ESS),exhibiting significant advantages in terms of controllability and meeting requirements of Plug-and-Play(PnP)operations.However,during device plug-in and-out processes,improper systemparametersmay lead to small-signal stability issues.Therefore,before executing PnP operations,conducting stability analysis and adjusting parameters swiftly is crucial.This study introduces a four-stage strategy for parameter optimization to enhance systemstability efficiently.In the first stage,state-of-the-art technologies in measurement and communication are utilized to correct model parameters.Then,a novel indicator is adopted to identify the key parameters that influence stability in the second stage.Moreover,in the third stage,a local-parameter-tuning strategy,which leverages rapid parameter boundary calculations as a more efficient alternative to plotting root loci,is used to tune the selected parameters.Considering that the local-parameter-tuning strategy may fail due to some operating parameters being limited in adjustment,a multiparameter-tuning strategy based on the particle swarm optimization(PSO)is proposed to comprehensively adjust the dominant parameters to improve the stability margin of the system.Lastly,system stability is reassessed in the fourth stage.The proposed parameter-optimization strategy’s effectiveness has been validated through eigenvalue analysis and nonlinear time-domain simulations.展开更多
DC component is contained in inverter output voltage due to many reasons such as the zero-point deviation of operational amplifiers and the differences between power switching transistors′ characteristics. For the pa...DC component is contained in inverter output voltage due to many reasons such as the zero-point deviation of operational amplifiers and the differences between power switching transistors′ characteristics. For the parallel inverter system without output isolation transformers, the difference of DC components of the output voltage can cause large DC loop-current among modular inverters. Aiming at this problem, this paper studies several DC loop-current detecting and restraining methods. By digital adjustment with high precision on the DC components of reference sine wave, the DC components of inverter′s output voltage can be adjusted to restrain DC loop-current. Experimental results prove that the DC loop-current detecting and restraining methods have a good performance.展开更多
Threshold decision is an important function of nuclear instrument control system based on physical parameters threshold decision. Because the conventional decision methods lack correlation with time and conditions, by...Threshold decision is an important function of nuclear instrument control system based on physical parameters threshold decision. Because the conventional decision methods lack correlation with time and conditions, by analyzing the existing methods, some optimized methods are adopted. Considering safety, those methods are improved in data processing algorithms, floating threshold with multiple values, association with specific working condition, etc. These measures im- prove the nuclear instrument control system in fault tolerance and fault diagnosis, especially, the shutdown number of nucle- ar power plant decreases.展开更多
An overview of recent advances in digital control of low-to medium-power DC/DC switching converters is presented.Traditionally,analog electronics methods have dominated in controlling such DC/DC converters.However,wit...An overview of recent advances in digital control of low-to medium-power DC/DC switching converters is presented.Traditionally,analog electronics methods have dominated in controlling such DC/DC converters.However,with the steadily decreasing cost of ICs,the feasibility of digitally controlled DC/DC switching converters has increased sig-nificantly.This paper outlines a sample of digital solutions for DC/DC switching converters to enhance the performance of DC/DC switching converters.Furthermore,latest research activities pertaining to applications for steady-state and dy-namic performance improvement,such as efficiency optimization,controller auto tuning,and capacitor charge balance control,is discussed.These applications demonstrate the significant advantages and potentials of digital control.展开更多
以数字信号控制器(Digital Signal Controller,DSC)MC56F8323为主处理单元,提出一种具有数字预测的非线性PID控制器。设计并实现了模块化高压输入航空静止DC/DC变换器原理样机,给出了该样机的总体结构方案、关键硬件电路、相应的软件流...以数字信号控制器(Digital Signal Controller,DSC)MC56F8323为主处理单元,提出一种具有数字预测的非线性PID控制器。设计并实现了模块化高压输入航空静止DC/DC变换器原理样机,给出了该样机的总体结构方案、关键硬件电路、相应的软件流程和实验结论。5 kW样机验证了数字控制所带来的优良的系统性能。展开更多
基金supported by State Grid Information and Telecommunication Group Scientific and Technological Innovation Project“Research on Power Digital Space Technology System and Key Technologies”(Program No.SGIT0000XMJS2310456).
文摘By integrating advanced digital technologies such as cloud computing and the Internet of Things in sensor measurement,information communication,and other fields,the digital DC distribution network can efficiently and reliably access DistributedGenerator(DG)and Energy Storage Systems(ESS),exhibiting significant advantages in terms of controllability and meeting requirements of Plug-and-Play(PnP)operations.However,during device plug-in and-out processes,improper systemparametersmay lead to small-signal stability issues.Therefore,before executing PnP operations,conducting stability analysis and adjusting parameters swiftly is crucial.This study introduces a four-stage strategy for parameter optimization to enhance systemstability efficiently.In the first stage,state-of-the-art technologies in measurement and communication are utilized to correct model parameters.Then,a novel indicator is adopted to identify the key parameters that influence stability in the second stage.Moreover,in the third stage,a local-parameter-tuning strategy,which leverages rapid parameter boundary calculations as a more efficient alternative to plotting root loci,is used to tune the selected parameters.Considering that the local-parameter-tuning strategy may fail due to some operating parameters being limited in adjustment,a multiparameter-tuning strategy based on the particle swarm optimization(PSO)is proposed to comprehensively adjust the dominant parameters to improve the stability margin of the system.Lastly,system stability is reassessed in the fourth stage.The proposed parameter-optimization strategy’s effectiveness has been validated through eigenvalue analysis and nonlinear time-domain simulations.
文摘DC component is contained in inverter output voltage due to many reasons such as the zero-point deviation of operational amplifiers and the differences between power switching transistors′ characteristics. For the parallel inverter system without output isolation transformers, the difference of DC components of the output voltage can cause large DC loop-current among modular inverters. Aiming at this problem, this paper studies several DC loop-current detecting and restraining methods. By digital adjustment with high precision on the DC components of reference sine wave, the DC components of inverter′s output voltage can be adjusted to restrain DC loop-current. Experimental results prove that the DC loop-current detecting and restraining methods have a good performance.
基金Research Project of Hunan Province Education Department(No.14C0972)
文摘Threshold decision is an important function of nuclear instrument control system based on physical parameters threshold decision. Because the conventional decision methods lack correlation with time and conditions, by analyzing the existing methods, some optimized methods are adopted. Considering safety, those methods are improved in data processing algorithms, floating threshold with multiple values, association with specific working condition, etc. These measures im- prove the nuclear instrument control system in fault tolerance and fault diagnosis, especially, the shutdown number of nucle- ar power plant decreases.
文摘An overview of recent advances in digital control of low-to medium-power DC/DC switching converters is presented.Traditionally,analog electronics methods have dominated in controlling such DC/DC converters.However,with the steadily decreasing cost of ICs,the feasibility of digitally controlled DC/DC switching converters has increased sig-nificantly.This paper outlines a sample of digital solutions for DC/DC switching converters to enhance the performance of DC/DC switching converters.Furthermore,latest research activities pertaining to applications for steady-state and dy-namic performance improvement,such as efficiency optimization,controller auto tuning,and capacitor charge balance control,is discussed.These applications demonstrate the significant advantages and potentials of digital control.
文摘以数字信号控制器(Digital Signal Controller,DSC)MC56F8323为主处理单元,提出一种具有数字预测的非线性PID控制器。设计并实现了模块化高压输入航空静止DC/DC变换器原理样机,给出了该样机的总体结构方案、关键硬件电路、相应的软件流程和实验结论。5 kW样机验证了数字控制所带来的优良的系统性能。
