Integration of UPQC for Power Quality improvement in distributed generation network - a review <s> I. INTRODUCTION <s> Power Quality Enhancement Using Custom Power Devices considers the structure, control and performance of series compensating DVR, the shunt DSTATCOM and the shunt with series UPQC for power quality improvement in electricity distribution. ::: Also addressed are other power electronic devices for improving power quality in Solid State Transfer Switches and Fault Current Limiters. Applications for these technologies as they relate to compensating busses supplied by a weak line and for distributed generation connections in rural networks, are included. In depth treatment of inverters to achieve voltage support, voltage balancing, harmonic suppression and transient suppression in realistic network environments are also covered. New material on the potential for shunt and series compensation which emphasizes the importance of control design has been introduced. ::: Power Quality Enhancement Using Custom Power Devices is appropriate for distribution engineers, graduate engineers and designers working in the area of power electronic applications for power systems. Sections of the book on power quality issues and generation connection make for a timely reference for undergraduates studying distribution engineering. ::: Written for: ::: Distribution engineers, graduate engineers and designers working in the area of power electronic applications for power systems, students <s> BIB001 </s> Integration of UPQC for Power Quality improvement in distributed generation network - a review <s> I. INTRODUCTION <s> This paper describes analysis results of a combined operation of the unified power quality conditioner with the distributed generation. The proposed system consists of a series inverter, a shunt inverter, and a distributed generator connected in the dc link through a rectifier. The proposed system can compensate voltage sag and swell, voltage interruption, harmonics, and reactive power in both interconnected mode and islanding mode. The performance of proposed system was analyzed using simulations with power system computer aided design/electromagnetic transients dc analysis program, and experimental results with the hardware prototype. The proposed system can improve the power quality at the point of installation on power distribution systems or industrial power systems. <s> BIB002
The increasing demand of Distributed Generation (DG) in recent years, to minimize the gap between the supply and load demand, is introducing some voltage and current disturbance and harmonics due to the generator types and the interfacing power electronics converters. Therefore, quality of power supply has become an important issue with the increasing demand of DG systems either connected to the grid through grid-tie inverters or work in isolated (microgrid) mode. The need for monitoring of power quality in low voltage distribution levels and ways to mitigate the problems are also increasing due to better customer service, reasonably priced meters, telecommunication development, network planning, operation and regulation requirements  . Implementation of Custom Power Devices (CPD) like UPQC in DG or microgrid systems to improve the power quality is gaining greater importance BIB002 BIB001    . UPQC is the integration of series and shunt active filters, connected back-to-back on the dc side, sharing a common DC capacitor BIB001 as shown in Figure 1 . level; balanced and distortion free. The shunt component is responsible for mitigating the current quality problems caused by the consumer: poor power factor, load harmonic currents, load unbalance etc. It injects currents in the ac system such that the source currents become balanced sinusoids and in phase with the source voltages. This paper deals with the review of research work that has been completed so far on this issue. Emphasis has been given on incorporation techniques of UPQC in DG or microgrid system along with their advantages and disadvantages. More DGs such as Photovoltaic or Wind Energy Systems are now penetrating into the grid or microgrid. Again, numbers of nonlinear loads are also increasing. Therefore, current research on capacity enhancement techniques of UPQC to cope up with the expanding DG or microgrid system is also reviewed. 