Firts of all i want to apologize for the gramatical errors, i'm not a native english speaker, but i really need help with this topic.
I'm an intern in the electrical company of my country, at the present time the company is focusing its efforts to reduce tha technical and non technical loses in the distribution system, i was assigned the task of look into the behavior of star-delta connection transformers banks of high consumers, my job is basically use a amperimetric clamp and measure the currents of MV side, LV side and circulating currents, also power factor, impedancy of the bank and position of the tap's selector. The electrical system in my country has been left behind for decades making it a non-regulated system until now, i often find customers with circulating currents in the LV side, 8 times higher than the most high line current, note that almost all clients have unbalanced loads and power factor up to 0.9, what makes this to happen? if you see how much current enters in the primary and how much is out trought the secondary you can see heavy losses, what makes de banks to have this kind of behavior? the currents between phases shouldn't be line currents/√3 ? an unbalanced bank in delta will have phase currents higher than tha line currents in an effort to "balance" the loads? I know that for a real analysis we need the angles of the currents, but with the information avaliable, what conclusions can we obtain?
This is a short list of the costumers that I've inspected, the blue was de only one with a "theoretical" behavior, the others seems to have a erratical demeanor.
I'm an intern in the electrical company of my country, at the present time the company is focusing its efforts to reduce tha technical and non technical loses in the distribution system, i was assigned the task of look into the behavior of star-delta connection transformers banks of high consumers, my job is basically use a amperimetric clamp and measure the currents of MV side, LV side and circulating currents, also power factor, impedancy of the bank and position of the tap's selector. The electrical system in my country has been left behind for decades making it a non-regulated system until now, i often find customers with circulating currents in the LV side, 8 times higher than the most high line current, note that almost all clients have unbalanced loads and power factor up to 0.9, what makes this to happen? if you see how much current enters in the primary and how much is out trought the secondary you can see heavy losses, what makes de banks to have this kind of behavior? the currents between phases shouldn't be line currents/√3 ? an unbalanced bank in delta will have phase currents higher than tha line currents in an effort to "balance" the loads? I know that for a real analysis we need the angles of the currents, but with the information avaliable, what conclusions can we obtain?
This is a short list of the costumers that I've inspected, the blue was de only one with a "theoretical" behavior, the others seems to have a erratical demeanor.
| Client | Primary Voltage | Secundary Voltage | Total KVA of the bank | Impedancy's % | Primary Current A | Primary Current B | Primary Current C | Secundary Current A | Secundary Current B | Secundary Current C | Neutral Current | AB Current | BC Current | CA Current |
| FARAJ JESUS | 13,8 | 120/240 | 225 | 2,32 | 0,4 | 1 | 1,7 | 62,1 | 28,1 | 47,2 | 15,9 | 28,8 | 58 | 61,3 |
| CANAHUATI MOURRA ISSA ABDALA | 13,8 | 240 | 225 | 2,39 | 0,2 | 4,1 | 5,5 | 94,9 | 185 | 74,8 | 27,9 | 104,3 | 153,2 | 89,1 |
| MINISTERIO EDUC CTHA | 13,8 | 240 | 225 | 1,7 | 1,1 | 0,1 | 1,1 | 58,9 | 65,2 | 8 | 6 | 40,9 | 2,8 | 38,7 |
| ZIPPERS DE HONDURAS S A | 13,8 | 120/240 | 225 | 1,8 | 1,7 | 2,9 | 2 | 11,2 | 15,9 | 0,3 | 10,7 | 84,9 | 105,3 | 89,7 |
| COMERCIAL MADERERA NORIEGA | 13,8 | 240/480 | 501 | 2,8 | 2,7 | 5,8 | 5,4 | 48,7 | 76 | 67,7 | 0,9 | 51,4 | 94,8 | 54 |
| AGUA DE CHOLOMA | 13,8 | 240/480 | 300 | 1,84 | 8,2 | 11,8 | 3,7 | 205 | 211 | 208 | 7,3 | 149,9 | 181,3 | 69 |
| CORDOBA RODOLFO | 13,8 | 240/480 | 225 | NV | 7,5 | 7,3 | 7,2 | 22,1 | 10,1 | 15,8 | 34,3 | 230 | 215 | 225 |
| EXA S A | 34,5 | 240 | 55 | NV | 0,3 | 0,5 | 0,3 | 66 | 91 | 27,8 | 23,6 | 63,1 | 44,3 | 36,1 |
| INVERSIONES MONSOL | 34,5 | 240 | 225 | NV | 1,25 | 0,3 | 0,6 | 24,2 | 20,6 | 22 | 2,7 | 86,1 | 88,7 | 99,4 |
| BABUN SIKAFFY ROBERTO RAMIRO | 34,5 | 240 | 250 | NV | 1,4 | 1,7 | 0,1 | 76,8 | 73,7 | 63,1 | 9 | 2,3 | 65 | 74,1 |
| PRODUCTOS MINERALES VENTURA | 34,5 | 240 | 300 | 2,3 | 0,5 | 12,6 | 1,6 | 241 | 233 | 140,1 | 11 | 231 | 75,4 | 73 |
| COMPAÑÍA AZUCARERA CHUMBAGUA | 34,5 | 480 | 501 | 3,1 | 1,4 | 2,4 | 1,4 | 3,3 | 0,2 | 1,6 | *** | 53,6 | 50,9 | 55,2 |
| COOPROLAVE | 34,5 | 240 | 225 | 2,18 | 0,3 | 0,4 | 0,3 | 19,6 | 29 | 16,9 | 3,3 | 21,3 | 28,9 | 34,9 |
| MOLINA ROSALES JOSE ANTONIO | 34,5 | 240 | 300 | 2,28 y2,23 | 3,4 | 3,9 | 3 | 456 | 436 | 422 | *** | 252 | 286 | 253 |
| FUNDACION ESCUELA MHOTIVO | 13,8 | 120/240 | 501 | 2 | 2,2 | 5,1 | 0,8 | 208 | 233 | 90,3 | 7,8 | 94,6 | 9,3 | 96,1 |
| CHAVEZ M JUAN CARLOS | 13,8 | 240/480 | 501 | 2,2 | 2,5 | 4,2 | 1,4 | 131,8 | 134,8 | 128,3 | 3,3 | 25,1 | 58,3 | 71,6 |
| BENEFICIO MENDEZ SA | 13,8 | 120/240 | 300 | 1,79 | 0,2 | 0,1 | 0,1 | 7,8 | 7,6 | 7,8 | 0,3 | 2,5 | 5,3 | 2,4 |
| INAMI | 13,8 | 120/241 | 225 | 2 | 0,1 | 0,1 | 0,1 | 4,3 | 2,8 | 0,1 | 1,3 | 4,3 | 0,2 | 0,1 |
