As an essential part of the industrial Internet of Things(IoT)in power systems,the development of advanced metering infrastructure(AMI)facilitates services such as energy monitoring,load forecasting,and demand respons...As an essential part of the industrial Internet of Things(IoT)in power systems,the development of advanced metering infrastructure(AMI)facilitates services such as energy monitoring,load forecasting,and demand response.However,there is a growing risk of privacy disclosure with the wide installation of smart meters,for they transmit readings and sensitive data simultaneously.To guarantee the confidentiality of the sensitive information and authenticity of smart meter readings,we proposed a privacy-preserving scheme based on digital watermarking and elliptic-curve cryptography(ECC)asymmetric encryption.The sensitive data are encrypted using the public key and are hidden in the collected readings using digital watermark.Only the authorized user can extract watermark and can decrypt the confidential data using its private key.The proposed method realizes secure end-to-end confidentiality of the sensitive information.It has faster computing speed and can verify the data source and ensure the authenticity of readings.The example results show that the proposed method has little influence on the original data and unauthorized access cannot be completed within a reasonable time.On embedded hardware,the processing speed of the proposed method is better than the existing methods.展开更多
This paper presents the control ofa WECS （wind energy conversion system）, equipped with a DFIG （doubly fed induction generator）, for maximum power generation and power quality improvement simultaneously. The propo...This paper presents the control ofa WECS （wind energy conversion system）, equipped with a DFIG （doubly fed induction generator）, for maximum power generation and power quality improvement simultaneously. The proposed control algorithm is applied to a DFIG whose stator is directly connected to the grid and the rotor is connected to the grid through a back-to-back AC-DC-AC PWM （pulse width modulation） converter. The RSC （rotor side converter） is controlled in such a way to extract a maximum power, for a wide range of wind speed. The GSC （grid side converter） is controlled in order to filter harmonic currents of a nonlinear load coupled at the PCC （point of common coupling） and ensure smooth DC bus voltage. Simulation results show that the wind turbine can operate at its optimum energy for a wide range of wind speed and power quality improvement is achieved.展开更多
With the increasing development of wind power,the scale of wind farms and unit capacity of wind turbines are getting larger and larger,and the impact of wind integration on power systems cannot be ignored.However,in m...With the increasing development of wind power,the scale of wind farms and unit capacity of wind turbines are getting larger and larger,and the impact of wind integration on power systems cannot be ignored.However,in most cases,the areas with a plenty of wind resources do not have strong grid structures.Furthermore,the characteristics of wind power dictate that wind turbines need to absorb reactive power during operation.Because of the strong correlation between voltage stability and systems' reactive power,the impacts of wind integration on voltage stability has become an important issue.Based on the power system simulation software DIgSILENT and combined analysis of actual practice,this paper investigates the impacts of two types of wind farms on voltage stability:namely a type of wind farms which are constituted by constant speed wind turbines based on common induction generators(IG) and another type of wind farms which are constituted by VSCF wind turbines based on doubly-fed induction generators(DFIG).Through investigation the critical fault clearing time is presented for different outputs of wind farms.Moreover,the impacts of static var compensator(SVC) and static synchronous compensator(STATCOM) on transient voltage stability in IG-based wind farms are studied to improve the security and stability of the Jiangsu power grid after the integration of large scale wind power.展开更多
基金Project(SGZJHZ00HLJS2000871)supported by the State Grid Science and Technology Project,China。
文摘As an essential part of the industrial Internet of Things(IoT)in power systems,the development of advanced metering infrastructure(AMI)facilitates services such as energy monitoring,load forecasting,and demand response.However,there is a growing risk of privacy disclosure with the wide installation of smart meters,for they transmit readings and sensitive data simultaneously.To guarantee the confidentiality of the sensitive information and authenticity of smart meter readings,we proposed a privacy-preserving scheme based on digital watermarking and elliptic-curve cryptography(ECC)asymmetric encryption.The sensitive data are encrypted using the public key and are hidden in the collected readings using digital watermark.Only the authorized user can extract watermark and can decrypt the confidential data using its private key.The proposed method realizes secure end-to-end confidentiality of the sensitive information.It has faster computing speed and can verify the data source and ensure the authenticity of readings.The example results show that the proposed method has little influence on the original data and unauthorized access cannot be completed within a reasonable time.On embedded hardware,the processing speed of the proposed method is better than the existing methods.
文摘This paper presents the control ofa WECS （wind energy conversion system）, equipped with a DFIG （doubly fed induction generator）, for maximum power generation and power quality improvement simultaneously. The proposed control algorithm is applied to a DFIG whose stator is directly connected to the grid and the rotor is connected to the grid through a back-to-back AC-DC-AC PWM （pulse width modulation） converter. The RSC （rotor side converter） is controlled in such a way to extract a maximum power, for a wide range of wind speed. The GSC （grid side converter） is controlled in order to filter harmonic currents of a nonlinear load coupled at the PCC （point of common coupling） and ensure smooth DC bus voltage. Simulation results show that the wind turbine can operate at its optimum energy for a wide range of wind speed and power quality improvement is achieved.
文摘With the increasing development of wind power,the scale of wind farms and unit capacity of wind turbines are getting larger and larger,and the impact of wind integration on power systems cannot be ignored.However,in most cases,the areas with a plenty of wind resources do not have strong grid structures.Furthermore,the characteristics of wind power dictate that wind turbines need to absorb reactive power during operation.Because of the strong correlation between voltage stability and systems' reactive power,the impacts of wind integration on voltage stability has become an important issue.Based on the power system simulation software DIgSILENT and combined analysis of actual practice,this paper investigates the impacts of two types of wind farms on voltage stability:namely a type of wind farms which are constituted by constant speed wind turbines based on common induction generators(IG) and another type of wind farms which are constituted by VSCF wind turbines based on doubly-fed induction generators(DFIG).Through investigation the critical fault clearing time is presented for different outputs of wind farms.Moreover,the impacts of static var compensator(SVC) and static synchronous compensator(STATCOM) on transient voltage stability in IG-based wind farms are studied to improve the security and stability of the Jiangsu power grid after the integration of large scale wind power.
