Application of Multilevel Voltage Inverters in Distributed Series Compensation Devices

Vestnik MEI ◽  
2021 ◽  
Vol 3 (3) ◽  
pp. 58-66
Author(s):  
Pavel A. Rashitov ◽  
◽  
Dmitriy A. Seregin ◽  
Mikhail D. Anikin ◽  
Evgeniy A. Vershanskiy ◽  
...  
Keyword(s):  
Power Transmission ◽  
Operation Mode ◽  
Current Transformer ◽  
Storage Capacitor ◽  
Series Compensation ◽  
Spectral Modeling ◽  
Power Circuit ◽  
Circuit Components ◽  
Compensation Device ◽  
Harmonic Composition

The operation principles of multilevel inverter circuits and methods for controlling them are considered. The operation of a multilevel circuit as part of a distributed transformer-based series compensation device is analyzed. The specific feature pertinent to the operation of a self-excited inverter within a distributed series compensation device is that it is loaded on the transformer connected in series into the power transmission line. In this case, the load is in fact a current transformer. Analytical expressions for calculating the circuit parameters are presented. The results of spectral modeling and simulation of the multilevel circuit in different modes of its operation are given. By using the spectral modeling, the currents and voltages of all power circuit components and their harmonic composition were estimated in the steady-state operation mode, and it has been shown that inductive injection is the heaviest mode of operation, because the inverter current reaches its maximum value in this mode. In using the multilevel circuit, additional requirements are posed to the control system, which, in addition to ensuring stable control of the output voltage, must also balance the voltages across the capacitors in the inverter arm. In selecting a storage capacitor and filter capacitor, it should be borne in mind that the maximum possible voltage across these components is determined not only by the necessary boost voltage, but also by the line current in the rectifier mode and can be significantly higher than the originally evaluated value. The obtained results can be used in designing distributed series compensation devices on the basis of an NPC inverter.

scholarly journals The Effects of the Reverse Current Caused by the Series Compensation on the Current Differential Protection

2014 ◽  
Vol 2014 ◽  
pp. 1-6
Author(s):  
Cui Tang ◽  
Xianggen Yin ◽  
Xuanwei Qi ◽  
Zhe Zhang ◽  
Minghao Wen
Keyword(s):  
Transmission Lines ◽  
Power Transmission ◽  
Operation Mode ◽  
Reverse Current ◽  
Engineering Practice ◽  
Differential Protection ◽  
Power Transmission Lines ◽  
Long Distance ◽  
Series Compensation ◽  
Current Differential Protection

The series capacitor compensation is one of the key technologies in the EHV and UHV long distance power transmission lines. This paper analyzes the operation characteristics of the main protection combined with the engineering practice when the transmission line overcompensation due to the series compensation system is modified and analyzes the influence of the transition resistance and the system operation mode on the current differential protection. According to the simulation results, it presents countermeasure on improving the sensitivity of differential current protection.

Novel transient stability analysis of grid connected hybrid wind/PV system using UPFC

2021 ◽  
pp. 002072092110032
Author(s):  
S Arockiaraj ◽  
BV Manikandan
Keyword(s):  
Fuzzy Logic ◽  
Transient Stability ◽  
Fuzzy Logic Controller ◽  
Power Transmission ◽  
Dynamic Performance ◽  
Wind Farms ◽  
Pv System ◽  
Turbine Generator ◽  
Series Compensation ◽  
Wind Turbine System

In transmission line, the series compensation is used to improve stability and increases the power transmission capacity. It generates sub synchronous resonance (SSR) at turbine-generator shaft due to the interaction between the series compensation and wind turbine system. To solve this, several methods have been presented. However, these provide less performance during contingency period. Therefore, to mitigate the SSR and also to improve the dynamic performance of hybrid wind and PV system connected with series compensated wind farms, the adaptive technique of the Black Widow Optimization algorithm based Fuzzy Logic Controller (BWO-FLC) with UPFC is proposed in this paper. Here, the objective function is solved optimally using BWO technique. Based on this, the Fuzzy Logic Controller is designed. The results proved that the proposed controller performs the mitigation of SSR. The damping ratios of proposed controller to mitigation of SSR are 0.0098, 0.0139, and 0.0195 for wind speed of 6, 8 and 10 m/s respectively.

Study on the characteristics of secondary arc current of UHV high compensation degree TCSC line under the fine-tuning mode

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Baina He ◽  
Yadi Xie ◽  
Jingru Zhang ◽  
Nirmal-Kumar C. Nair ◽  
Xingmin He ◽  
...  
Keyword(s):  
Transmission Line ◽  
Transmission Lines ◽  
Stability Margin ◽  
Transmission Capacity ◽  
Fine Tuning ◽  
Series Compensation ◽  
Arc Current ◽  
Compensation Device ◽  
The Stability ◽  
Recovery Voltage

Abstract In the transmission line, the series compensation device is often used to improve the transmission capacity. However, when the fixed series capacitor (FSC) is used in high compensation series compensation device, the stability margin cannot meet the requirements. Therefore, thyristor controlled series compensator (TCSC) is often installed in transmission lines to improve the transmission capacity of the line and the stability of the system. For cost considerations, the hybrid compensation mode of FSC and TCSC is often adopted. However, when a single-phase grounding fault occurs in a transmission line with increased series compensation degree, the unreasonable distribution of FSC and TCSC will lead to the excessive amplitude of secondary arc current, which is not conducive to rapid arc extinguishing. To solve this problem, this paper is based on 1000 kV Changzhi-Nanyang-Jingmen UHV series compensation transmission system, using PSCAD simulation program to established UHV series compensation simulation model, The variation law of secondary arc current and recovery voltage during operation in fine tuning mode after adding TCSC to UHV transmission line is analyzed, and the effect of increasing series compensation degree on secondary arc current and recovery voltage characteristics is studied. And analyze the secondary arc current and recovery voltage when using different FSC and TCSC series compensation degree schemes, and get the most reasonable series compensation configuration scheme. The results show that TCSC compensation is more beneficial to arc extinguishing under the same series compensation. Compared with several series compensation schemes, it is found that with the increase of the proportion of TCSC, the amplitude of secondary arc current and recovery voltage vary greatly. Considering various factors, the scheme that is more conducive to accelerating arc extinguishing is chosen.

LOW-POWER, PARALLEL INTERFACE WITH CONTINUOUS-TIME ADAPTIVE PASSIVE EQUALIZER AND CROSSTALK CANCELLATION

2005 ◽  
Vol 15 (02) ◽  
pp. 459-476
Author(s):  
C. PATRICK YUE ◽  
JAEJIN PARK ◽  
RUIFENG SUN ◽  
L. RICK CARLEY ◽  
FRANK O'MAHONY
Keyword(s):  
Low Power ◽  
Electromagnetic Interference ◽  
Continuous Time ◽  
High Speed ◽  
High Performance ◽  
Process Variations ◽  
Cmos Process ◽  
Power Circuit ◽  
Crosstalk Cancellation ◽  
Circuit Components

This paper presents the low-power circuit techniques suitable for high-speed digital parallel interfaces each operating at over 10 Gbps. One potential application for such high-performance I/Os is the interface between the channel IC and the magnetic read head in future compact hard disk systems. First, a crosstalk cancellation technique using a novel data encoding scheme is introduced to suppress electromagnetic interference (EMI) generated by the adjacent parallel I/Os . This technique is implemented utilizing a novel 8-4-PAM signaling with a data look-ahead algorithm. The key circuit components in the high-speed interface transceiver including the receive sampler, the phase interpolator, and the transmitter output driver are described in detail. Designed in a 0.13-μm digital CMOS process, the transceiver consumes 310 mW per 10-Gps channel from a I-V supply based on simulation results. Next, a 20-Gbps continuous-time adaptive passive equalizer utilizing on-chip lumped RLC components is described. Passive equalizers offer the advantages of higher bandwidth and lower power consumption compared with conventional designs using active filter. A low-power, continuous-time servo loop is designed to automatically adjust the equalizer frequency response for the optimal gain compensation. The equalizer not only adapts to different channel characteristics, but also accommodates temperature and process variations. Implemented in a 0.25-μm, 1P6M BiCMOS process, the equalizer can compensate up to 20 dB of loss at 10 GHz while only consumes 32 mW from a 2.5-V supply.

Impact of 750kV Transmission Line Series Compensation Capacity on Power Frequency Overvoltage

2014 ◽  
Vol 986-987 ◽  
pp. 330-333
Author(s):  
Ding Jun Wen ◽  
Xiu Bin Zhang ◽  
Hong Gang Chen ◽  
Feng Jiang ◽  
Ya Ming Sun
Keyword(s):  
Transmission Line ◽  
Single Phase ◽  
Power Transmission ◽  
Series Compensation ◽  
Two Phase ◽  
Transient Model ◽  
Power Frequency ◽  
Arc Current ◽  
Recovery Voltage ◽  
Insulation Coordination

The overvoltage calculation of 750kV transmission line with series compensation has great significance on the design, insulation coordination and protection of the line. In this paper, a transient model of 750kV power transmission system with series compensation is established. Effects of different capacity on no-load capacitive rise overvoltage, single-phase grounding overvoltage, two-phase grounding overvoltage are calculated. Secondary arc current and recovery voltage of different series compensation capacity in single-phase grounding is also calculated.

scholarly journals Placement of shunt reactors in high-voltage network using fuzzy constraints

2019 ◽  
Vol 139 ◽  
pp. 01052
Author(s):  
Arif Hashimov ◽  
Huseyngulu Guliyev ◽  
Aytek Babayeva
Keyword(s):  
High Voltage ◽  
Reactive Power ◽  
Power Transmission ◽  
Operation Mode ◽  
Ease Of Use ◽  
Electrical Network ◽  
Control Voltage ◽  
Fuzzy Constraints ◽  
Definition Of ◽  
Shunt Reactors

In recent years, controlled shunt reactors (CSR) relevant to the class of FACTS facilities have been widely used to control voltage modes and reactive power flows in the high-voltage electrical network. The selection of location, as well as the definition of the law of CSR control in the conditions of stochastic variability of the operation mode of high-voltage power transmission, are associated with numerous technical and economic factors. At the same time, such constraint conditions as ease of use, performance efficiency, purpose and location in the system, as well as the period of commissioning should be taken into account. In the proposed procedure these factors are considered as fuzzy constraints. The procedure of CSR placement in the 330 kV electrical network of Azerenergy system for control of reactive power flows taking into account the mentioned fuzzy constraints is proposed. The obtained simulation results confirm the advantage of the proposed procedure.

scholarly journals Duty-Cycled Wireless Power Transmission for Millimeter-Sized Biomedical Implants

Electronics ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 2130
Author(s):  
Muhammad Abrar Akram ◽  
Kai-Wen Yang ◽  
Sohmyung Ha
Keyword(s):  
Duty Cycle ◽  
Power Transmission ◽  
Electromagnetic Coupling ◽  
System Level ◽  
Cmos Process ◽  
Biomedical Implants ◽  
Wireless Power ◽  
Wireless Power Transmission ◽  
Short Period ◽  
Circuit Components

Wireless power transmission (WPT) using an inductively coupled link is one of the most popular approaches to deliver power wirelessly to biomedical implants. As the electromagnetic wave travels through the tissue, it is attenuated and absorbed by the tissue, resulting in much weaker electromagnetic coupling than in the air. As a result, the received input power on the implant is very weak, and so is the input voltage at the rectifier, which is the first block that receives the power on the implant. With such a small voltage amplitude, the rectifier inevitably has a very poor power conversion efficiency (PCE), leading to a poor power transfer efficiency (PTE) of the overall WPT system. To address this challenge, we propose a new system-level WPT method based on duty cycling of the power transmission for millimeter-scale implants. In the proposed method, the power transmitter (TX) transmits the wave with a duty cycle. It transmits only during a short period of time and pauses for a while instead of transmitting the wave continuously. In doing so, the TX power during the active period can be increased while preserving the average TX power and the specific absorption rate (SAR). Then, the incoming voltage becomes significantly larger at the rectifier, so the rectifier can rectify the input with a higher PCE, leading to improved PTE. To investigate the design challenges and applicability of the proposed duty-cycled WPT method, a case for powering a 1 × 1-mm2-sized neural implant through the skull is constructed. The implant, a TX, and the associated environment are modeled in High-Frequency Structure Simulator (HFSS), and the circuit simulations are conducted in Cadence with circuit components in a 180-nm CMOS process. At a load resistor of 100 kΩ, an output capacitor of 4 nF, and a carrier frequency of 144 MHz, the rectifier’s DC output voltage and PCE are increased by 300% (from 1.5 V to 6 V) and by 50% (from 14% to 64%), respectively, when the duty cycle ratio of the proposed duty-cycled power transmission is varied from 100% to 5%.

Understanding the Reactive Power Problem and a Mechanical Solution Using Peaking or Retired Generators

2014 ◽  
Author(s):  
Randall M. Attix ◽  
D. M. Chamberlin
Keyword(s):  
Electric Power ◽  
Delivery System ◽  
Reactive Power ◽  
Power Delivery ◽  
Prime Mover ◽  
Power Circuit ◽  
Real Power ◽  
Circuit Components ◽  
Inherent Nature ◽  
Power Problem

Reactive power is an unwanted but unavoidable part of alternating current electric power delivery systems. Governed by the laws of physics, it occurs due to the inherent nature of the components of these systems. This article develops an understanding of reactive power and the control of it to reduce its adverse effects and to improve the efficiency of an electric power delivery system. The article begins by identifying and representing electric power circuit components, real power, and reactive power. These are then mathematically shown how they interact and affect the power delivery system. Control and mitigation of the effects of reactive power are then developed with emphasis on mechanical solutions using rotating machines. In particular, peaking or retired generators are identified for use as rotating condensers as well as new installations. A description of the gear type synchronous self-synchronizing (SSS) overrunning clutches used to connect and dis-connect a generator from the peaking prime mover or the retired generator from a starting system is included.

Sign in / Sign up

Export Citation Format

Share Document