rockman7892
Electrical
- Apr 7, 2008
- 1,174
I was reading an article in my latest IEEE IAS magazine discussing how "smart inverters" can be used for scheduling of loads but also can be used to provide reactive power to loads in an islanding mode as well as provide reactive compensation for voltage support at the POCC. These inverters in this discussion were said to be viewed as voltage source inverters capable of supplying reactive power.
Prior to reading this my only experience has been with grid-tied inverters that were viewed as current source inverters and not capable of supplying reactive power. My understanding of these inverters was they they were synced to the grid voltage and frequency and simply supplied current as a current source to the loads.
Can anyone explain the differences between these two inverters how they are constructed and or operated that let them operate as a voltage source or current source inverter.
With a current source inverter how is reactive power prevented from being supplied and the p.f. kept near unity? Would this mean that a motor connected to a grid tied inverter would need to pull its reactive power from the grid and if the inverter was somehow able to be islanded it would not be able to supply the reactive power to the motor?
Does the current source inverter somehow keep the current angle fixed to create a unity p.f. while the voltage source inverter is allowed to have the current angle phase shifted from the voltage?
Prior to reading this my only experience has been with grid-tied inverters that were viewed as current source inverters and not capable of supplying reactive power. My understanding of these inverters was they they were synced to the grid voltage and frequency and simply supplied current as a current source to the loads.
Can anyone explain the differences between these two inverters how they are constructed and or operated that let them operate as a voltage source or current source inverter.
With a current source inverter how is reactive power prevented from being supplied and the p.f. kept near unity? Would this mean that a motor connected to a grid tied inverter would need to pull its reactive power from the grid and if the inverter was somehow able to be islanded it would not be able to supply the reactive power to the motor?
Does the current source inverter somehow keep the current angle fixed to create a unity p.f. while the voltage source inverter is allowed to have the current angle phase shifted from the voltage?