Some studies of distributed series FACTS controller to control active power flow through transmission line

Power flow control is important in power systems and recently becomes more urgent because of the deregulation. This paper presents a novel configuration of unified power flow controller and performance of UPFC intended for installation on transmission line. When no UPFC is installed, any interruption in the line due to fault reduces the active power flow through the line. Installing the UPFC makes it possible to control an amount of active power flow through the line. Simulations were carried out using Matlab to validate the performance of UPFC. Keywords: FACTS Devices, UPFC, Transient stability, Matlab, Fault simulation.

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Parameter Determination for Back-to-Back Converters in Power Systems to Enhance Interface Flow Margins

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.433-440.3964 ◽

2012 ◽

Vol 433-440 ◽

pp. 3964-3968

Author(s):

Sung Min Ohn ◽

Hwa Chang Song ◽

Byong Hoon Jang

Keyword(s):

Power Systems ◽

Power Flow ◽

Optimization Problem ◽

Active Power ◽

Current Level ◽

Parameter Determination ◽

Fault Current ◽

Load Demand ◽

Active Power Flow ◽

Flow Through

This paper presents a method to determine parameters of BTB (back-to-back) converters in terms of the enhancement of interface flow margins. Interface flow margin is by definition a measure of how much active power can be transferred from the external areas to the study area with the fixed load demand, and it is mainly constrained by system voltage stability. BTB converters are controllable equipments with the active power flow through them, and its DC link in fact can divide the AC systems at the location and hence can reduce the fault current level. This paper first calculates margin enhancement sensitivities at the nose point of F-V curves and formulates an optimization problem to update the BTB parameters to improve the margins. This procedure is repeated performed until the required margin enhancement is achieved.

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TOTAL HARMONIC DISTORTION REDUCTION BY USING SSSC WITH AND WITHOUT BVSI

International Journal of Power System Operation and Energy Management ◽

10.47893/ijpsoem.2014.1124 ◽

2014 ◽

pp. 54-64

Author(s):

SURYA PRAKASH ◽

KAMTA PRASAD VERMA ◽

BRIJESH SINGH

Keyword(s):

Transmission Line ◽

Power Flow ◽

Power Transmission ◽

Harmonic Distortion ◽

Phase Relationship ◽

Active Power ◽

Voltage Source ◽

Positive System ◽

Voltage Source Inverter ◽

Active Power Flow

This electronic document is a “live” template. The various In present a new Static Synchronous Series Compensator (SSSC) for the control of active power flow on a transmission line is proposed and its effectiveness is investigated. The new SSSC is based on injecting a voltage in a given line to counter or augment the voltage &Power produced by the inductive reactance of the line. The resulting compensator, therefore, emulates the control of transmission line reactance and thus, it assists in control by the power transmission capacity. The voltage to be injected in a line is produced by a Binary Voltage Source Inverter (BVSI). BVSI is an attractive recently proposed Voltage Source Inverter. Its output contains very little harmonics and it utilizes very few dc sources unlike conventional multi-level VSIs. The % phase output of the BVSI is synchronized to the line frequency and its phase is arranged to be in or out of phase with the Line reactance drop. The proposed BVSI-SSSC is realized by using three binary proportioned dc sources, which may be appropriately dimensioned capacitors. The resulting output of a BVSI-SSSC is a 15-step ac voltage waveform. The BVSISSSC has a sophisticated set of coordinated controlled which ensure: BVSI frequency is in synchronism with the system frequency, firing pulses are regulated for inverter valves to ensure minimum harmonic content, the selection of Modulation Index and arrangement regulates an appropriate phase relationship to create the desired change in the power flow, and adjustment of firing angles to ensure that the capacitors creating dc binary proportioned sources maintain desired charge on them. Armillary controls may be added to create positive system damping through active power control, and voltage dependent controllers may be added to limit over and under voltage (charging) of capacitors during fault conditions.

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