samppa
Newbie level 5
Hi all,
I have a simpe but very tricky problem/question regarding power measurement that I would like to share with you. I have been thinking about this for a while, and cannot achieve a solution, or even a statement that is this possible or not.
The case is, that I would need to measure a simple european style 230VAC 3-phase delta-connected load of three impedances R1, R2 and R3 only by using current and voltage meters at the line voltage supply leads V1, V2 and V3. I need to solve the power dissipation for each of the impedances R1, R2 and R3, which are not balanced and may even have different power factors. In the example picture they have been marked as 10R, 20R and 30R, but in reality these are unknown.
This would of course be trivial, if I could place the meters inside the load device between the impedances R1, R2, R2, but that is physically impossible. Also, this would be trivial, if I could somehow use the Delta-Wye tranformation, but I have reasoned that it is also impossible as the impedances are unknown.
Somehow I think that I can't be the first one to wish for this kind of solution, so all tips for prior solutions are very welcome. I have calculated the currents and powers in vector form a couple of times with different excel sheets, but always end up in a dead end. It would be great to get a somehow fresh start, or a clear indication that this is not even possible
Regards,
Samppa
I have a simpe but very tricky problem/question regarding power measurement that I would like to share with you. I have been thinking about this for a while, and cannot achieve a solution, or even a statement that is this possible or not.
The case is, that I would need to measure a simple european style 230VAC 3-phase delta-connected load of three impedances R1, R2 and R3 only by using current and voltage meters at the line voltage supply leads V1, V2 and V3. I need to solve the power dissipation for each of the impedances R1, R2 and R3, which are not balanced and may even have different power factors. In the example picture they have been marked as 10R, 20R and 30R, but in reality these are unknown.
This would of course be trivial, if I could place the meters inside the load device between the impedances R1, R2, R2, but that is physically impossible. Also, this would be trivial, if I could somehow use the Delta-Wye tranformation, but I have reasoned that it is also impossible as the impedances are unknown.
Somehow I think that I can't be the first one to wish for this kind of solution, so all tips for prior solutions are very welcome. I have calculated the currents and powers in vector form a couple of times with different excel sheets, but always end up in a dead end. It would be great to get a somehow fresh start, or a clear indication that this is not even possible
Regards,
Samppa
