Abstract
Multimodal sub-synchronous resonance (SSR) induced by the interactions between the generator shafts and the fixed series capacitors has become a serious threat for the power system. To overcome this, a voltage source converter (VSC) based controller for multimodal SSR suppression, named sub-synchronous resonance dynamic suppressor (SSRDS), is presented and analyzed in this paper. The controller is placed at the point of common coupling (PCC) of the power plant for multi-generator SSR suppression purpose so that the investment costs can be minimized while making sure the requirements of the SSR damping. To quantify the contribution of SSRDS to the SSR damping, the damping torque analysis is carried out, which can reveal the influences of the operating conditions and the correlated control parameters on the damping performance. Furthermore, to avoid the negative affects between the different TMs in close range as well as maximize the damping ability of SSRDS, the parameters tuning method of the mode filters and the gain and phase shifters are proposed. A detailed nonlinear simulation model is established in PSCAD/EMTDC based on the Jinjie series compensated transmission system located in China. The damping torque analysis, the eigenvalues analysis and the simulation results have fully demonstrated the effectiveness and the robustness of the proposed SSRDS for multi-generator and multimodal SSR suppression under both small and large disturbances in various operating conditions.
Highlights
As a simple and economic solution, the series compensation transmission system has been widely utilized in practical power system [1] in order to enhance system stability and promote the transmission capacity limitation
It has following advantages: 1) the synchronous resonance dynamic suppressor (SSRDS) is an independent device and is dedicatedly designed for synchronous resonance (SSR) suppression rather than voltage support, which will only be activated when SSR occurs; 2) the parameters tuning method of the mode filters and the gain and phase shifters can guarantee that the negative impacts from the interactions between the different torsional modes (TMs) in close range can be minimized and the damping capability of SSRDS can be maximized; 3) the controller is placed at the point of common coupling (PCC) of the power plant for multigenerator SSR suppression purpose so that the investment costs are reduced while guaranteeing the requirements of the SSR damping
The SSRDS is composed of a damping signal control loop, a dq vector control loop and a voltage source converter
Summary
As a simple and economic solution, the series compensation transmission system has been widely utilized in practical power system [1] in order to enhance system stability and promote the transmission capacity limitation. MAIN CONTRIBUTION This paper introduces an improved VSC based controller for multimodal and multi-generator SSR suppression, which is named as SSRDS It has following advantages: 1) the SSRDS is an independent device and is dedicatedly designed for SSR suppression rather than voltage support, which will only be activated when SSR occurs; 2) the parameters tuning method of the mode filters and the gain and phase shifters can guarantee that the negative impacts from the interactions between the different TMs in close range can be minimized and the damping capability of SSRDS can be maximized; 3) the controller is placed at the PCC of the power plant for multigenerator SSR suppression purpose so that the investment costs are reduced while guaranteeing the requirements of the SSR damping. For the Jinjie Power Plants in the case study later on, one SSRDS rated at 40 MVA can stabilize SSR modes of six large-capacity generators by fully utilizing the capacity of the controller under elaborate design of the control parameters Under this scheme, the number of backup controllers can decrease and the overall investment costs will be less. Once SSR occurs, the reactive damping current will be modulated for SSR damping support
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
