A Multi-frequency DQ Impedance Measurement Algorithm for Single-phase Vehicle-grid System in Electrified Railways

2021 ◽  
pp. 1-1
Author(s):  
Zhigang Liu ◽  
Guorong Li ◽  
Xiangyu Meng ◽  
Heng Zhou ◽  
Jiawei Liu
Keyword(s):  
Single Phase ◽  
Impedance Measurement ◽  
Grid System ◽  
Measurement Algorithm ◽  
Electrified Railways

Improving the Efficiency of High-Speed AC Contact Suspension

2021 ◽  
Vol 5 (5) ◽  
pp. 39-43
Author(s):  
Maksim V. SHEVLYUGIN ◽  
◽  
Daria V. SEMENOVA ◽  
Keyword(s):  
Power Supply ◽  
High Speed ◽  
Single Phase ◽  
New Technologies ◽  
Alternating Current ◽  
Rolling Stock ◽  
New Materials ◽  
High Speed Railway ◽  
Electric Rolling Stock ◽  
Electrified Railways

When developing a high-speed contact suspension for railways electrified with alternating current, it is important to ensure that the electric rolling stock passes the neutral insert without turning off the current and without reducing the speed of movement. The article provides an analysis of previously developed devices in the field of power supply of electrified railways of single-phase alternating current, in which an attempt was made to pass an electric rolling stock of a neutral insert without disconnecting the load. The device of isolating coupling of a catenary and a neutral insert for high-speed railway lines electrified on alternating current is described. In this case, the passage of the neutral insert is carried out under current and braking of the electric rolling stock will not occur. Among other things, to improve the efficiency of high-speed contact suspension for railways electrified with alternating current, it is proposed to use new materials and new technologies that can be used in the device of insulating coupling of the catenary

Micro-grid System Modeling Efforts using PQ-Control for Single-phase and Three-phase Inverter

2018 ◽  
Author(s):  
Gina Munoz Quintero ◽  
Yaswanth Reddy Challapuram ◽  
Argenis Bilbao ◽  
Stephen B. Bayne ◽  
Anitha Sarah Subburaj ◽  
...  
Keyword(s):  
Single Phase ◽  
System Modeling ◽  
Grid System ◽  
Phase Inverter ◽  
Three Phase ◽  
Micro Grid ◽  
Three Phase Inverter

scholarly journals A study of a single phase grid connected pv inverter performance under a weak grid conditions and distorted grid voltage for Cambodia

2021 ◽  
Vol 12 (2) ◽  
pp. 1055
Author(s):  
Sovanna Phoeurn ◽  
Sakda Somkun
Keyword(s):  
Single Phase ◽  
Stability Control ◽  
System Control ◽  
Grid System ◽  
Grid Voltage ◽  
Power System Control ◽  
Power Meter ◽  
Weak Grid ◽  
Pv Inverter ◽  
Distorted Grid

<span lang="EN-US">A single-phase grid-connected PV inverter performance under a weak grid is a model designed to penetrate PV energy with a weak grid. Usually, this model gets complex and unstable in power system control such as THD growth, harmonic effects, voltage surges, inverter performance. Experimental results would present the impacts on the system which would lead to instability in the grid system. This study was based on inverter performance control, a weak grid control, the grid distortion examination, and harmonic effects. To optimize this grid system, hence, the proposed methods of oscilloscope and power meter were proportionally used to control the grid impacts and stabilities. The results showed that current THD in distorted grid voltage system surged to 8.88%. V<sub>PCC</sub> growth was 238.11V, equivalent to 8.23% in a weak grid (X<sub>L</sub> and R). Such a huge increase could prevent the grid system from transferring power for later operation. During the experiment, the inverter, S power and Q power performances stood for good operating processes without impacts on the grid performance. This method  should be applied with a weak grid system because it provided information about grid stability control.</span>

Study on a New Setting Method of Distance Relay with Superconducting Fault Current Limiter Adapt in the Grid

2012 ◽  
Vol 588-589 ◽  
pp. 471-474
Author(s):  
Jun Mei ◽  
Bin Liu ◽  
Jian Yong Zheng ◽  
Lei Yao
Keyword(s):  
Transmission Lines ◽  
Single Phase ◽  
Short Circuit ◽  
Impedance Measurement ◽  
Simulation Software ◽  
Fault Current ◽  
Fault Current Limiter ◽  
Distance Protection ◽  
Superconducting Fault Current Limiter ◽  
Current Limiter

Considerable attention is given towards developing Superconducting fault current limiter (SFCL) due to increasing short circuit levels in transmission lines, which itself imposes further changes on the measured impendence at the relaying point and causes significant impact on the lines’ relay protection, especially on the distance protection as the single-phase grounding fault occurs. In this paper, resistive superconducting fault current limiter connected to the grid is studied as the model to analysis how SFCL affects the grounded short-circuit impedance relay’s setting, then an new setting method of distance protection for the SFCL-equipped line is proposed. Finally, a power system model is built to analysis the theory by PSCAD / EMTDC simulation software. The results show that in the condition of using the impedance relays’ new setting method, impedance measurement error is greatly reduced, SFCL and line distance protection can work in coordination with each other properly.

scholarly journals A Single-Phase Dual-Stage PV-Grid System with Active Filtering

2015 ◽  
Vol 6 (3) ◽  
pp. 449
Author(s):  
Slamet Riyadi ◽  
Yanuarsyah Haroen
Keyword(s):  
Single Phase ◽  
Active Power Filter ◽  
Active Power ◽  
Grid System ◽  
Power Filter ◽  
Pv Modules ◽  
Dual Stage ◽  
Active Filtering ◽  
Pv Grid ◽  
A Current

Integrating photovoltaic based electricity into the grid and power quality improvement have become two major issues in electrical system. Formerly, these can be solved by using two converter systems separately, a PV-Grid System and an active power filter. But recent technology uses only a converter system to do both function. An existed shunt active power filter (SAPF) can be modified to form a dual-stage PV-Grid with active filtering capability. In this paper, a PV-Grid System that is capable to transfer all power generated by PV modules and reduce harmonic contents is proposed. The system was formed by connecting a boost chopper as a Maximum Power Point Tracker and PV modules to the DC-link capacitor of a single-phase SAPF. It just needed a current transducer and also required simpler control circuits. A voltage controller was needed to achieve power equilibrium while a current controller was needed to make the grid current sinusoidal with unity power factor. To verify the analysis, simulations and experiments were done.

Sign in / Sign up

Export Citation Format

Share Document