The inconsistency of the cells in a battery pack can affect its lifespan,safety and reliability in the electric vehicles. The balanced system is an effective technique to reduce its inconsistency and improve the opera...The inconsistency of the cells in a battery pack can affect its lifespan,safety and reliability in the electric vehicles. The balanced system is an effective technique to reduce its inconsistency and improve the operating performance. A hybrid equilibrium strategy based on decision combing battery state-of-charge( SOC) and voltage has been proposed. The battery SOC is estimated through an improved least squares method. An equalization hardware in loop( HIL) platform has been constructed. Based on this HIL platform,equilibrium strategy has been verified under the constant-current-constant-voltage( CCCV) and dynamicstresstest( DST) conditions. Experimental results indicate that the proposed hybrid equalization strategy can achieve good balance effect and avoid the overcharge and over-discharge of the battery pack at the same time.展开更多
This paper presents a framework of a multi-terminal HVDC transmission system and its multi-functional control strategy.The framework possesses the basic characteristics of the DC-grid and is suitable in integrating di...This paper presents a framework of a multi-terminal HVDC transmission system and its multi-functional control strategy.The framework possesses the basic characteristics of the DC-grid and is suitable in integrating distributed power sources.The paper proposes the first architecture for a multiterminal HVDC transmission system using the VSC technology.Its control strategy offers various functionalities that include controls for operation mode,start-up and shutdown,DC voltage,and station online re-connecting,which are significantly different from the control of point-to-point VSC-HVDC systems.The framework has not only been evaluated in real-time simulation studies,but has also been implemented onsite for the first time via the China Southern Grid's Nan'ao Multi-terminal VSCHVDC(VSC-MTDC)project.This paper gives a brief review of the current research and engineering achievements in this field,which includes four aspects:the architecture of the VSCMTDC system,the structure of the control and protection system,simulation verification tests setting,and the results of real-time hardware in hardware in loop(HIL)simulation studies and onsite tests.展开更多
基金Supported by the National Natural Science Foundation of China(51507012)Beijing Nova Program(Z171100001117063)
文摘The inconsistency of the cells in a battery pack can affect its lifespan,safety and reliability in the electric vehicles. The balanced system is an effective technique to reduce its inconsistency and improve the operating performance. A hybrid equilibrium strategy based on decision combing battery state-of-charge( SOC) and voltage has been proposed. The battery SOC is estimated through an improved least squares method. An equalization hardware in loop( HIL) platform has been constructed. Based on this HIL platform,equilibrium strategy has been verified under the constant-current-constant-voltage( CCCV) and dynamicstresstest( DST) conditions. Experimental results indicate that the proposed hybrid equalization strategy can achieve good balance effect and avoid the overcharge and over-discharge of the battery pack at the same time.
基金supported by the 863 National High Technology Research and Development Program of China(2011AA05AI02)China Southern Power Grid Company.
文摘This paper presents a framework of a multi-terminal HVDC transmission system and its multi-functional control strategy.The framework possesses the basic characteristics of the DC-grid and is suitable in integrating distributed power sources.The paper proposes the first architecture for a multiterminal HVDC transmission system using the VSC technology.Its control strategy offers various functionalities that include controls for operation mode,start-up and shutdown,DC voltage,and station online re-connecting,which are significantly different from the control of point-to-point VSC-HVDC systems.The framework has not only been evaluated in real-time simulation studies,but has also been implemented onsite for the first time via the China Southern Grid's Nan'ao Multi-terminal VSCHVDC(VSC-MTDC)project.This paper gives a brief review of the current research and engineering achievements in this field,which includes four aspects:the architecture of the VSCMTDC system,the structure of the control and protection system,simulation verification tests setting,and the results of real-time hardware in hardware in loop(HIL)simulation studies and onsite tests.