Optimal Operation of Hybrid AC/DC Distribution Network with High Penetrated Renewable Energy

2018 ◽  
Author(s):  
Zhenyu Zhuo ◽  
Ning Zhang ◽  
Chongqing Kang ◽  
RuiBiao Dong ◽  
Yongxiao Liu
Keyword(s):  
Renewable Energy ◽  
Distribution Network ◽  
Optimal Operation ◽  
Dc Distribution

scholarly journals Convex Approximation Algorithm for AC/DC Distribution Network With Energy Router

2021 ◽  
Vol 9 ◽  
Author(s):  
Tao Zhang ◽  
Yunfei Mu ◽  
Xiaoyu Wang ◽  
Youjun Deng ◽  
Yi Song ◽  
...  
Keyword(s):  
Approximation Algorithm ◽  
Distribution Network ◽  
Distribution Networks ◽  
Optimal Operation ◽  
Convex Programming Problem ◽  
Convex Approximation ◽  
Approximation Approach ◽  
Flow Equations ◽  
Dc Distribution ◽  
Highly Nonlinear

The optimal operation model of AC/DC distribution network with energy router (ER) is essentially a nonconvex nonlinear programming (NLP) problem. In order to improve the feasibility of solving the model, a convex approximation algorithm is proposed in this work. The steady-state model of ER is developed with considering the loss characteristics and multiport coordinated control strategy. It is embedded in the optimization formulations of AC/DC network as basic operating equations. Then, using second-order cone relaxation technology, the power flow equations of AC and DC distribution networks are convexly relaxed. On this basis, the highly nonlinear operating model of ER is linearized by introducing a successive approximation approach. Therefore, the original NLP problem is transformed into the convex programming problem and the solution efficiency is improved. Meanwhile, an iterative solution algorithm is developed to ensure the accuracy of the convex approximation approach. Simulation results verify the feasibility and efficiency of the proposed algorithm.

Optimal operation of AC–DC distribution network with multi park integrated energy subnetworks considering flexibility

2020 ◽  
Vol 14 (6) ◽  
pp. 1004-1019
Author(s):  
Qi Geng ◽  
Yan Hu ◽  
Jianzong He ◽  
Yongyan Zhou ◽  
Wei Zhao ◽  
...  
Keyword(s):  
Distribution Network ◽  
Optimal Operation ◽  
Dc Distribution

A Combined AC+DC Distribution Network Interconnected with Renewable Energy

2014 ◽  
Vol 960-961 ◽  
pp. 676-679
Author(s):  
Dong Xin Hao ◽  
Li Zhang ◽  
Meng Qi Liu ◽  
Pan Ting Dong ◽  
Hao Wu
Keyword(s):  
Renewable Energy ◽  
Reactive Power ◽  
Voltage Drop ◽  
Electrical Power ◽  
Distribution Network ◽  
Transient State ◽  
Transient Effects ◽  
Line Voltage ◽  
Dc Power ◽  
Dc Distribution

The combined AC+DC distribution network in this study provides a coupling and decoupling strategy of renewable energy in DC mode by using zig-zag transformer, which makes each line transmit AC electrical power and DC power simultaneously. The proposed scheme is digitally simulated with the help of Simulink software package. Simulation results indicate lower line voltage drop and less active and reactive power loss in steady state; almost similar or even better transient effects in transient state, which demonstrates the feasibility of combined AC+DC distribution network of single line interconnected with renewable energy.

scholarly journals The LCOE-Indicator-Based Comprehensive Economic Comparison between AC and DC Power Distribution Networks with High Penetration of Renewable Energy

Energies ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4621 ◽  
Author(s):  
Yi Liu ◽  
Zhanqing Yu ◽  
Haibo Li ◽  
Rong Zeng
Keyword(s):  
Renewable Energy ◽  
Economic Evaluation ◽  
Power Loss ◽  
Distribution Network ◽  
Distribution Networks ◽  
Planning Stage ◽  
Stage Of Development ◽  
Dc Distribution ◽  
High Penetration ◽  
Economic Comparison

DC distribution networks are operationally economical from the perspective of renewable energy penetration due to the reduction of power loss from the simplified power conversion structure. However, the initial investment cost of a DC network is high because DC technology is in the early stage of development. So, selecting AC or DC technology becomes an important issue in the planning stage of a distribution network, where a comprehensive quantitative economic comparison between AC and DC distribution networks is necessary. To compare the economy between AC and DC distribution networks with high penetration of a renewable energy scenario, this paper introduces a comprehensive economic evaluation method. In this study, first, typical system models for AC and DC distribution networks were proposed as the foundation of the research. Then, a levelized cost of energy (LCOE)-indicator-based comprehensive economic evaluation model was established, where the operation cost was classified into power loss cost, reliability loss cost, and operational cost. A time sequential simulation model was applied to calculate the power loss. The simulation results showed that a DC distribution network has higher initial investment, operation, and maintenance costs than an AC distribution network, but the loss cost is far lower than an AC distribution network. A sensitivity analysis showed that the equipment cost and proportion of renewable energy are two of the most important factors that affect the economics of DC distribution networks at present.

A Novel Method of Core Saturation Suppression for the AC+DC Distribution Network Transformer

2014 ◽  
Vol 960-961 ◽  
pp. 680-683
Author(s):  
Meng Qi Liu ◽  
Li Zhang ◽  
Jie Lou ◽  
Liang Zou ◽  
Tong Zhao
Keyword(s):  
Renewable Energy ◽  
Simulation Model ◽  
Future Study ◽  
Smart Grids ◽  
Rapid Development ◽  
Distribution Network ◽  
Iron Core ◽  
Core Saturation ◽  
Dc Distribution ◽  
Novel Method

With the rapid development of smart grids, the interconnection between the grid and distributed renewable energy is the inevitable trend of future study. Because of the existence of the DC source in the combined AC-DC distribution network, the transformer iron core is easily saturated generating lots of harmonics and increasing the loss of the transformer. This paper presents a novel method based on inductive filtering technology of core saturation suppression of the transformer in the combined AC-DC distribution network, this novel method can suppress the harmonics caused by the flux saturation and forbid the harmonics intruding into the ac grid. In the end we build the simulation model to prove the correctness and practicability of this novel method.

scholarly journals Optimal Operation Strategy of Flexible Interconnected Distribution Network Based on SES-VSC-MTDC

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Le Ge ◽  
Limin Lu ◽  
Xiaodong Yuan ◽  
Yongzhou Yu
Keyword(s):  
Renewable Energy ◽  
Energy Storage ◽  
Control Strategy ◽  
Optimal Power Flow ◽  
Distribution Network ◽  
Distribution Networks ◽  
Optimal Operation ◽  
Power Regulation ◽  
Primal Dual ◽  
Regulation Model

The increasing integration of renewable energy is challenging the secure operation of the power system. System flexibility or the capability to address the significant power fluctuations from renewable energy is becoming more and more relevant. Self-energy storage-based multiterminal back-to-back VSC-HVDC (SES-VSC-MTDC) technology is first proposed, and it can realize the power regulation on both temporal and spatial dimensions, which helps improve the power supply reliability and the capacity to accommodate renewable energy of the interconnected distribution networks. Then, to address the coordination control problem of the energy storage and back-to-back VSC-HVDC, a comprehensive control strategy of SES-VSC-MTDC is proposed based on the optimal power flow preprocessing and state of charge interval division. Then, the power regulation model and the energy-power regulation timing model of SES-VSC-MTDC are established for different control strategies. Then, we use the primal-dual interior-point method to solve the developed optimal operation model of flexible interconnected distribution network. Finally, a 33-bus system with four interconnected feeders is used to test the effectiveness of the SES-VSC-MTDC technology and its operation control strategy.

Sign in / Sign up

Export Citation Format

Share Document