Patents by Inventor Defu Cai

Defu Cai has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 12119650
    Abstract: Disclosed is an optimal power flow-based hierarchical control method for a distributed energy storage system (ESS), where the method divides control of an energy storage cluster into three layers, performs primary and secondary control to realize intra-cluster control, and performs tertiary control to realize inter-cluster control. In the primary control, droop coefficients are set to realize intra-cluster basic power distribution. In the secondary control, a frequency/voltage shift and uneven power distribution that are caused by a droop are compensated for based on a consistency algorithm. In the tertiary control, a central controller is set, a solution of an optimal power flow is calculated and delivered to each cluster as a control signal, and the control signal is tracked in real time through the secondary control and the primary control. The method adjusts a reference voltage of each energy storage cluster without requiring a common bus.
    Type: Grant
    Filed: September 1, 2022
    Date of Patent: October 15, 2024
    Assignee: State Grid Hubei Electric Power Research Institute
    Inventors: Defu Cai, Kunpeng Zhou, Zuowei Wang, Xiaohui Li, Li Wan, Haiguang Liu, Rusi Chen, Wenna Wang, Tao Wang, Liangyi Zhang, Guanqun Sun, Erxi Wang
  • Publication number: 20240222976
    Abstract: Disclosed is an optimal power flow-based hierarchical control method for a distributed energy storage system (ESS), where the method divides control of an energy storage cluster into three layers, performs primary and secondary control to realize intra-cluster control, and performs tertiary control to realize inter-cluster control. In the primary control, droop coefficients are set to realize intra-cluster basic power distribution. In the secondary control, a frequency/voltage shift and uneven power distribution that are caused by a droop are compensated for based on a consistency algorithm. In the tertiary control, a central controller is set, a solution of an optimal power flow is calculated and delivered to each cluster as a control signal, and the control signal is tracked in real time through the secondary control and the primary control. The method adjusts a reference voltage of each energy storage cluster without requiring a common bus.
    Type: Application
    Filed: September 1, 2022
    Publication date: July 4, 2024
    Inventors: Defu Cai, Kunpeng Zhou, Zuowei Wang, Xiaohui Li, Li Wan, Haiguang Liu, Rusi Chen, Wenna Wang, Tao Wang, Liangyi Zhang, Guanqun Sun, Erxi Wang
  • Patent number: 6607050
    Abstract: An integrated ocean bottom towed four-component array for seismic data acquisition consists of a four-channel electronic section for seismic data collection, a gimbaled three-component geophone and a hydrophone in a housing. The array connects with a submarine cable through a cable joint in order to acquire four components of data consisting of seismic P wave, shear wave and hydrophone in total. Through cable data transmission and processing in a central station, ocean bottom oil and gas structure information can be obtained. Because of the high SNR acquisition in the ocean bottom seismic data acquisition of the present invention, and the waterproof cable interconnections between each of the sections of the present apparatus, data acquisition of high quality can be gained to realize highly efficient and easy ocean bottom towing operations.
    Type: Grant
    Filed: April 19, 2001
    Date of Patent: August 19, 2003
    Assignee: China National Petroleum Corporation
    Inventors: Guoxin He, Zailu Zhang, Peichang Li, Yi Lin, Xiaoquan Han, Defu Cai, Jingping Xiao, Yonglin Zhang
  • Publication number: 20010035311
    Abstract: An integrated ocean bottom towed four-component array for seismic data acquisition consists of a four-channel electronic section for seismic data collection, a gimbaled three-component geophone and a hydrophone in a housing. The array connects with a submarine cable through a cable joint in order to acquire four components of data consisting of seismic P wave, shear wave and hydrophone in total. Through cable data transmission and processing in a central station, ocean bottom oil and gas structure information can be obtained. Because of the high SNR acquisition in the ocean bottom seismic data acquisition of the present invention, and the waterproof cable interconnections between each of the sections of the present apparatus, data acquisition of high quality can be gained to realize highly efficient and easy ocean bottom towing operations.
    Type: Application
    Filed: April 19, 2001
    Publication date: November 1, 2001
    Applicant: China National Petroleum Corporation
    Inventors: Guoxin He, Zailu Zhang, Peichang Li, Yi Lin, Xiaoquan Han, Defu Cai, Jingping Xiao, Yonglin Zhang