Abstract: One of the key aspects of power quality improvement
in power system is the mitigation of voltage sags/swells and flicker.
Custom power devices have been known as the best tools for voltage
disturbances mitigation as well as reactive power compensation.
Dynamic Voltage Restorer (DVR) which is the most efficient and
effective modern custom power device can provide the most
commercial solution to solve several problems of power quality in
distribution networks. This paper deals with analysis and simulation
technique of DVR based on instantaneous power theory which is a
quick control to detect signals. The main purpose of this work is to
remove three important disturbances including voltage sags/swells
and flicker. Simulation of the proposed method was carried out on
two sample systems by using Matlab software environment and the
results of simulation show that the proposed method is able to
provide desirable power quality in the presence of wide range of
disturbances.
Abstract: Voltage sags are the most common power quality
disturbance in the distribution system. It occurs due to the fault in the
electrical network or by the starting of a large induction motor and
this can be solved by using the custom power devices such as
Dynamic Voltage Restorer (DVR). In this paper DVR is proposed to
compensate voltage sags on critical loads dynamically. The DVR
consists of VSC, injection transformers, passive filters and energy
storage (lead acid battery). By injecting an appropriate voltage, the
DVR restores a voltage waveform and ensures constant load voltage.
The simulation and experimental results of a DVR using MATLAB
software shows clearly the performance of the DVR in mitigating
voltage sags.
Abstract: In this paper the modeling and analysis of Space
Vector Pulse Width Modulation (SVPWM) based Dynamic Voltage
Restorer (DVR) using PSCAD/EMTDC software will be presented in
details. The simulation includes full modeling of the SVPWM
technique used to control the DVR inverter. A test power system
composed of three phase voltage source, sag generator, DVR and
three phase resistive load is used to demonstrate restoration capability
of the DVR. The simulation results of the presented DVR proved
excellent voltage sag mitigation to protect sensitive loads.
Abstract: Custom power is a technology driven product and
service solution which embraces a family devices such as Dynamic
Voltage Restorer (DVR), Distributed Shunt Compensator
(DSTATCOM), Solid State Breaker (SSB) etc which will provide
power quality functions at distribution voltages. The rapid response
of these devices enables them to operate in real time, providing
continuous and dynamic control of the supply including voltage and
reactive power regulation, harmonic reduction and elimination of
voltage dips. This paper presents the benefits of multilevel inverters
when they are used for DPC based custom power devices. Power
flow control mechanism, salient features, advantages and
disadvantages of direct power control (DPC) using lookup table,
SVM, predictive voltage vector and hybrid DPC strategies are
discussed in this paper. Simulation results of three level inverter
based STATCOM, harmonic analysis of multi level inverters are
presented at the end.