scholarly journals Research on the New Topology and Coordinated Control Strategy of Renewable Power Generation Connected MMC-Based DC Power Grid Integration System

Symmetry ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1965
Author(s):  
Shanshan Wang ◽  
Shanmeng Qin ◽  
Panbo Yang ◽  
Yuanyuan Sun ◽  
Bing Zhao ◽  
...  
Keyword(s):  
Control Strategy ◽  
Power Grid ◽  
Grid Integration ◽  
Multilevel Converter ◽  
Renewable Power ◽  
Dc Power ◽  
Fault Ride Through ◽  
Renewable Power Generation ◽  
Voltage Frequency ◽  
Renewable Energy Generation

The modular multilevel converter (MMC) station connected to the islanded renewable energy generation system needs to adopt the voltage frequency (VF) control to provide AC voltage. The single-pole converter fault will unbalance the input and output power of the DC power grid, which causes the DC voltage or the bridge arm current of the non-fault pole to exceed the protection value in the time scale of tens to hundreds of milliseconds, leading to cascading failures. To realize the fault ride-through (FRT) of single-pole converter fault, this paper analyzes the electrical characteristic of the system. Based on the analysis, the existing topology is optimized and the reasonable operation reserved margin is designed. Furthermore, the corresponding control strategy is proposed, which can not only ensure the single-pole converter block fault ride-through but can also realize economic, stable, and resilient power supply and address asymmetrical problems. Finally, the simulation model is built in PSCAD/EMTDC and the simulation results validate the effectiveness of the proposed control strategy.

scholarly journals Hysteresis Controlled Quadratic Boost Converter Based AC Micro Grid System with Improved Dynamic Response

2019 ◽  
Vol 8 (2S11) ◽  
pp. 3327-3337
Keyword(s):  
Closed Loop ◽  
Power Grid ◽  
Dynamic Performance ◽  
Boost Converter ◽  
Open Loop ◽  
Grid System ◽  
Renewable Power ◽  
Renewable Power Generation ◽  
Hysteresis Controller ◽  
Micro Grid

Renewable power generation and enabling of AC Microgrids are fundamentally changing the traditional power grid. Microgrid has revealed its promising potential as an active subsystem of the modern power grid. This paper reviews and analyses ways to boost and regulate the voltage of the AC-Micro-Grid-System(QBCIMGS) for improving the microgrid power quality. “A QBC(Quadratic-boost-converter-inverter based AC-Micro-Grid-System(QBCIMGS) is conferred-here”. This work recommends-QBC(quadratic-boost-converter) between rectifier &inverter. This paper investigates open loop and closed loop response of Quadratic boost-converter based AC-Micro-Grid-System(MGS) with Proportional resonant(PR) & Hysteresis-controller(HC). The mat lab outcome attained illustrates a developed dynamic-performance by using Hysteresiscontrolled AC-Micro-Grid-System(MGS)

scholarly journals Flexible Power System Defense Strategies in an Isolated Microgrid System with High Renewable Power Generation

2020 ◽  
Vol 10 (9) ◽  
pp. 3184
Author(s):  
Yuan-Kang Wu ◽  
Kuo-Ting Tang ◽  
Zheng Kuan Lin ◽  
Wen-Shan Tan
Keyword(s):  
Power Generation ◽  
Power System ◽  
Control Strategy ◽  
Frequency Stability ◽  
Operating Costs ◽  
Diesel Generator ◽  
Preventive Control ◽  
Defense Strategies ◽  
Renewable Power ◽  
Renewable Power Generation

This work develops an underfrequency preventive control strategy for an islanded power system with a high penetration of wind power generation. First, the preventive control strategy uses the frequency nadir forecasting module to analyze the frequency stability under largest diesel generator tripping (N-1) contingency events. If predicted frequency nadir is too low, four frequency support methods are then analyzed and used for preventing potential frequency stability problem. They include generator rescheduling (GR), the use of battery energy storage system (BESS), direct load control (DLC) and emergency demand response program (EDRP). In terms of the GR method, the optimal diesel generator dispatch is obtained, with sufficient frequency stability and minimal fuel cost and start-up cost. In the BESS method, the optimal instantaneous power output from BESS is obtained based on its frequency support capability. With the DLC or EDRP method, the optimal contract-based load-shedding or the load-reduction to provide frequency support is obtained, respectively. Then, the operating costs of each method to support frequency are analyzed. The research methods and simulation results are very useful to the low-frequency protection of actual power systems with high renewable power generation. This work proposed a complete defense strategy in a microgrid system. It combines GR, BESS, DLC and EDRP. Therefore, the system operators have many options to implement their defense strategies, based on the operating costs of various methods. In other words, the proposed defense strategy provides a more flexible solution for the protection of micro grids with a high renewable power penetration. Therefore, the solution considers the system safety and economical aspects.

scholarly journals An Original Control Strategy of Storage Systems for the Frequency Stability of Autonomous Grids with Renewable Power Generation

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4391
Author(s):  
Mariano G. Ippolito ◽  
Fabio Massaro ◽  
Rossano Musca ◽  
Gaetano Zizzo
Keyword(s):  
Power Generation ◽  
Control Strategy ◽  
Storage Systems ◽  
Renewable Energy Sources ◽  
Frequency Stability ◽  
Operating Conditions ◽  
Storage Unit ◽  
Renewable Power ◽  
Renewable Power Generation ◽  
Storage Units

This work examines the operation of the autonomous power system of a geographical island assuming the integration of significant generation shares from renewable energy sources and the installation of the required storage systems. The frequency stability of the system is investigated considering different operating conditions, in terms of load demand and renewable power generation. The main focus of the work is an original control strategy specifically designed for power converters interfacing storage units to the grid. The proposed strategy is based on an extended frequency droop control, which selects specific droop settings depending on the operating mode—charge or discharge—of the storage unit. A simulation model of the whole electrical system is developed for dynamic analysis. The model also implements the possibility of including specific auxiliary frequency controls for synthetic inertia and primary reserve. The results of the simulation and analysis indicate that the proposed control strategy has a significant positive effect, making the storage units able to provide a fundamental and more effective support to the frequency stability of the system. The application of the proposed control strategy to storage units also reduces the need for a contribution to the frequency control from intermittent and variable sources, making the whole system more robust, stable and reliable.

scholarly journals Study on Structure and Control Strategy of Hybrid AC / DC Power Grid

2018 ◽  
Vol 394 (4) ◽  
pp. 042110
Author(s):  
Haijun Liu ◽  
Shiyou Wang ◽  
Xuejiao Li ◽  
Zhe Zhou ◽  
Weiguo Li
Keyword(s):  
Control Strategy ◽  
Power Grid ◽  
Dc Power ◽  
And Control
Sign in / Sign up

Export Citation Format

Share Document