The recently proposed ambient signal-based load modeling approach offers an important and effective idea to study the time-varying and distributed characteristics of power loads.Meanwhile,it also brings new problems.S...The recently proposed ambient signal-based load modeling approach offers an important and effective idea to study the time-varying and distributed characteristics of power loads.Meanwhile,it also brings new problems.Since the load model parameters of power loads can be obtained in real-time for each load bus,the numerous identified parameters make parameter application difficult.In order to obtain the parameters suitable for off-line applications,load model parameter selection(LMPS)is first introduced in this paper.Meanwhile,the convolution neural network(CNN)is adopted to achieve the selection purpose from the perspective of short-term voltage stability.To begin with,the field phasor measurement unit(PMU)data from China Southern Power Grid are obtained for load model parameter identification,and the identification results of different substations during different times indicate the necessity of LMPS.Meanwhile,the simulation case of Guangdong Power Grid shows the process of LMPS,and the results from the CNNbased LMPS confirm its effectiveness.展开更多
At present,the Lu an Radio and Television Tower is the tallest building in Anhui Province,and it is easily struck by lightning during the thunderstorm season.In order to clearly understand the lightning environment ar...At present,the Lu an Radio and Television Tower is the tallest building in Anhui Province,and it is easily struck by lightning during the thunderstorm season.In order to clearly understand the lightning environment around the TV tower,based on the lightning positioning monitoring data provided by the Anhui Meteorological Bureau,the distribution characteristics of six lightning parameters within 5 km of the TV tower were studied firstly.Secondly,combined with the field survey data,a soil model was established,and the distribution of ground potential and other related parameters were simulated using CDEGS software,which can provide certain reference for the subsequent lightning protection design and construction.展开更多
To address the problem of insufficient system inertia and improve the power quality of grid-connected inverters,and to enhance the stability of the power system,a method to control a virtual synchronous generator(VSG)...To address the problem of insufficient system inertia and improve the power quality of grid-connected inverters,and to enhance the stability of the power system,a method to control a virtual synchronous generator(VSG)output voltage based on model predictive control(MPC)is proposed.Parameters of the inductors,capacitors and other components of the VSG can vary as the temperature and current changes.Consequently the VSG output voltage and power control accuracy using the conventional MPC method may be reduced.In this paper,to improve the parameter robustness of the MPC method,a new weighted predictive capacitor voltage control method is proposed.Through detailed theoretical analysis,the principle of the proposed method to reduce the influence of parameter errors on voltage tracking accuracy is analyzed.Finally,the effectiveness and feasibility of the proposed method are verified by experimental tests using the Typhoon control hardware-in-the-loop experimental platform.展开更多
For a multi-inverter grid-connected system,the stability of the point of common coupling(PCC)voltage is evaluated considering the distribution parameters of the transmission lines.First,the systems on both sides of th...For a multi-inverter grid-connected system,the stability of the point of common coupling(PCC)voltage is evaluated considering the distribution parameters of the transmission lines.First,the systems on both sides of the PCC are equalized,a smallsignal equivalent circuit similar to the“current source-grid”is established,and a mathematical model for the voltage of the PCC is derived.Then,using Euler’s formula and Nyquist stability criterion,the PCC voltage stability of the grid-connected system is evaluated by the impedance analysis method under the premise that the single-side excitation is stable.In addition,the gridconnected conditions causing PCC voltage instability are studied.A phase compensation method based on an impedance phase compensation control strategy is introduced.The stability of the grid-connected system is improved by compensating the phase margin at the equivalent impedance crossover-section frequency on both sides of the grid-connected system PCC.Finally,a simulation circuit is built to simulate and analyze the proposed model and phase compensation method.The simulation results verify the accuracy and effectiveness of the theoretical analysis.展开更多
基金supported by the National Natural Science Foundation of China(U2066601,U1766214).
文摘The recently proposed ambient signal-based load modeling approach offers an important and effective idea to study the time-varying and distributed characteristics of power loads.Meanwhile,it also brings new problems.Since the load model parameters of power loads can be obtained in real-time for each load bus,the numerous identified parameters make parameter application difficult.In order to obtain the parameters suitable for off-line applications,load model parameter selection(LMPS)is first introduced in this paper.Meanwhile,the convolution neural network(CNN)is adopted to achieve the selection purpose from the perspective of short-term voltage stability.To begin with,the field phasor measurement unit(PMU)data from China Southern Power Grid are obtained for load model parameter identification,and the identification results of different substations during different times indicate the necessity of LMPS.Meanwhile,the simulation case of Guangdong Power Grid shows the process of LMPS,and the results from the CNNbased LMPS confirm its effectiveness.
文摘At present,the Lu an Radio and Television Tower is the tallest building in Anhui Province,and it is easily struck by lightning during the thunderstorm season.In order to clearly understand the lightning environment around the TV tower,based on the lightning positioning monitoring data provided by the Anhui Meteorological Bureau,the distribution characteristics of six lightning parameters within 5 km of the TV tower were studied firstly.Secondly,combined with the field survey data,a soil model was established,and the distribution of ground potential and other related parameters were simulated using CDEGS software,which can provide certain reference for the subsequent lightning protection design and construction.
基金supported in part by the National Natural Science Foundation of China(51707176)in part by the Youth Talent Support Project of Henan Province(2019HYTP021)+1 种基金in part by the Youth Talent Support Project of Henan Province(2019HYTP021)in part by the Key Research,Development and Promotion Special Project(Science and Technology)of Henan Province(202102210103).
文摘To address the problem of insufficient system inertia and improve the power quality of grid-connected inverters,and to enhance the stability of the power system,a method to control a virtual synchronous generator(VSG)output voltage based on model predictive control(MPC)is proposed.Parameters of the inductors,capacitors and other components of the VSG can vary as the temperature and current changes.Consequently the VSG output voltage and power control accuracy using the conventional MPC method may be reduced.In this paper,to improve the parameter robustness of the MPC method,a new weighted predictive capacitor voltage control method is proposed.Through detailed theoretical analysis,the principle of the proposed method to reduce the influence of parameter errors on voltage tracking accuracy is analyzed.Finally,the effectiveness and feasibility of the proposed method are verified by experimental tests using the Typhoon control hardware-in-the-loop experimental platform.
文摘For a multi-inverter grid-connected system,the stability of the point of common coupling(PCC)voltage is evaluated considering the distribution parameters of the transmission lines.First,the systems on both sides of the PCC are equalized,a smallsignal equivalent circuit similar to the“current source-grid”is established,and a mathematical model for the voltage of the PCC is derived.Then,using Euler’s formula and Nyquist stability criterion,the PCC voltage stability of the grid-connected system is evaluated by the impedance analysis method under the premise that the single-side excitation is stable.In addition,the gridconnected conditions causing PCC voltage instability are studied.A phase compensation method based on an impedance phase compensation control strategy is introduced.The stability of the grid-connected system is improved by compensating the phase margin at the equivalent impedance crossover-section frequency on both sides of the grid-connected system PCC.Finally,a simulation circuit is built to simulate and analyze the proposed model and phase compensation method.The simulation results verify the accuracy and effectiveness of the theoretical analysis.
