29-06-2012, 11:10 AM
UPQC (Unified Power Quality Conditioner)
[attachment=26035]
A Unified Power Quality Conditioner (UPQC) is a device that is similar in construction to a Unified Power Flow Conditioner (UPFC). The UPQC, just as in a UPFC, employs two voltage source inverters (VSIs) that connected to a d.c. energy storage capacitor. One of these two VSIs is connected in series with a.c. line while the other is connected in shunt with the a.c. system.
A UPQC that combines the operations of a Distribution
Static Compensator (DSTATCOM) and Dynamic Voltage Regulator (DVR) together.
One of the serious problems in electrical systems is the increasing number of electronic components of devices that are used by industry as well as residences. These devices, which need high-quality energy to work properly, at the same time, are the most responsible ones for injections of harmonics in the distribution system. Therefore, devices that soften this drawback have been developed. One of them is the unified power quality conditioner (UPQC), It consists of a shunt- active filter together with a series-active filter.
supply voltages, so that compensated current drawn from the network and the compensated supply voltage delivered to the load are sinusoidal, balanced and minimized. The series- and shunt-active filters are connected in a back-to-back configuration, in which the shunt converter is responsible for regulating the common DC-link voltage.
A UPQC is employed in a power transmission system to perform shunt and series compensation at the same time. A power distribution system may contain unbalance, distortion and even d.c. components. Therefore a UPQC operate, better than a UPFC, with all these aspects in order to provide shunt or series compensation.
The UPQC is a relatively new device and not much work
has yet been reported on it. Sometimes it has been viewed as combination of series and shunt active filters.
CASE V:
If the terminal voltage is distorted one containing several harmonics, in such cases the series APF injects voltage equal to the sum of the harmonics voltage at PCC but in opposite direction. Thus the sum of voltage injected by series APF and distorted voltage at PCC will get cancelled out. During this voltage harmonic compensation mode of operation the series APF does not consume any real power from sources since it injects only harmonics voltage. Here UPQC works in zero active power consumption mode.
[attachment=26035]
A Unified Power Quality Conditioner (UPQC) is a device that is similar in construction to a Unified Power Flow Conditioner (UPFC). The UPQC, just as in a UPFC, employs two voltage source inverters (VSIs) that connected to a d.c. energy storage capacitor. One of these two VSIs is connected in series with a.c. line while the other is connected in shunt with the a.c. system.
A UPQC that combines the operations of a Distribution
Static Compensator (DSTATCOM) and Dynamic Voltage Regulator (DVR) together.
One of the serious problems in electrical systems is the increasing number of electronic components of devices that are used by industry as well as residences. These devices, which need high-quality energy to work properly, at the same time, are the most responsible ones for injections of harmonics in the distribution system. Therefore, devices that soften this drawback have been developed. One of them is the unified power quality conditioner (UPQC), It consists of a shunt- active filter together with a series-active filter.
supply voltages, so that compensated current drawn from the network and the compensated supply voltage delivered to the load are sinusoidal, balanced and minimized. The series- and shunt-active filters are connected in a back-to-back configuration, in which the shunt converter is responsible for regulating the common DC-link voltage.
A UPQC is employed in a power transmission system to perform shunt and series compensation at the same time. A power distribution system may contain unbalance, distortion and even d.c. components. Therefore a UPQC operate, better than a UPFC, with all these aspects in order to provide shunt or series compensation.
The UPQC is a relatively new device and not much work
has yet been reported on it. Sometimes it has been viewed as combination of series and shunt active filters.
CASE V:
If the terminal voltage is distorted one containing several harmonics, in such cases the series APF injects voltage equal to the sum of the harmonics voltage at PCC but in opposite direction. Thus the sum of voltage injected by series APF and distorted voltage at PCC will get cancelled out. During this voltage harmonic compensation mode of operation the series APF does not consume any real power from sources since it injects only harmonics voltage. Here UPQC works in zero active power consumption mode.