Distribution transformer capacity sequence grade optimizing method
Distribution transformer capacity sequence grade optimizing method
 CN 101,741,097 A
 Filed: 12/29/2009
 Published: 06/16/2010
 Est. Priority Date: 12/29/2009
 Status: Active Grant
First Claim
1. distribution transformer capacity sequence grade optimizing method is characterized in that:
 Under each average load rate of same load, close capacitance grade sequence is optimized, be optimized calculating according to following formula;
${\mathrm{\β\mathrm{ik}=\frac{{S}_{n}}{{S}_{i}}times;{\mathrm{beta;\mathrm{nk}}}_{}}}_{}$(k=1 wherein, 2,3 ...) (1) P _{ik}＝
AVERAGE[P _{0i}+K _{t}β
_{ik}^{2}P _{ki}+C(Q _{0i}+K _{t}β
_{ik}^{2}Q _{ki})]????????????????????(2) In formula (1) and (2);
S _{n}The reference capacity of selecting inthe grouping;
S _{i}I inthe grouping is waited level capacity;
β
_{Ik}distribution transformer capacity is S _{i}The time relative datum capacity S _{n}Conversion load factor under each load factor;
β
_{Nk}distribution transformer capacity reference capacity S _{n}The time load factor;
P _{Ik}Average load rate β
in the combination ofdistribution transformer capacity sequence _{Nk}Under the average composite loss of transformer;
P _{0i}distribution transformer capacity is S _{i}Specified unloaded active loss, unit is;
kW;
K _{t}fluctuation of load loss factor generally gets 1.05;
P _{Ki}distribution transformer capacity is S _{i}The nominal load active loss, unit is;
kW;
Q _{Ki}distribution transformer capacity is S _{i}Specified unloaded reactive loss, unit is;
kvar;
Cis idle economic equivalent, kW/kvar;
Idle herein economy is when measuring 0.1;
Distribution transformer at certain model carries out the capacitance grade sequence optimisation, at first should begin grouping from the minimum capacity grade according to the rated capacity of relevant existing standard defined and calculate;
The grouping minimum capacity grade in the normal capacity sequence exactly begins, general 4～
6 is one group, if find in calculating that flex point does not appear in the average composite loss curve of heap(ed) capacity grade in grouping yet, can continue to increase the capacitance grade number in the grouping.Concrete computational methods can be decomposed (2) formula;
Chinese PRB Reexamination
Abstract
The invention provides a distribution transformer capacity sequence grade optimizing method, belonging to the power system distribution transformer field. Firstly grouping calculation is started at minimum capacity grade sequence according to rated capacity specified by related existing standards, the calculation is stopped until an obvious inflection point appears on transformer average comprehensive damage curve, the capacity grade at the inflection point is the optimal capacity grade with minimum average comprehensive damage of the capacity grade sequence group, then capacity grade sequence grouping is continued by taking the next capacity grade as an initial point, optimizing calculation is carried out sequentially according to the steps until the inflection point appears, and the optimal capacity grade with minimum average comprehensive damage of the group is selected. The process is repeated, and finally optimized new capacity grade sequence is formed. Initial investment cost of distribution transformer can be effectively reduced, thus being beneficial to storage and dispatching of emergency goods and materials and running goods and materials of power system, and operating cost is reduced and the overall size advantage is developed, thus being beneficial to standardization and normalization of major equipment of distribution power system.

1 Citation
Method for calculating energy saving effect of transformer  
Patent #
CN 104,170,199 A
Filed 02/20/2012

Current Assignee

No References
2 Claims

1. distribution transformer capacity sequence grade optimizing method is characterized in that:

Under each average load rate of same load, close capacitance grade sequence is optimized, be optimized calculating according to following formula; ${\mathrm{\β\mathrm{ik}=\frac{{S}_{n}}{{S}_{i}}times;{\mathrm{beta;\mathrm{nk}}}_{}}}_{}$ (k=1 wherein, 2,3 ...) (1)P _{ik}＝
AVERAGE[P _{0i}+K _{t}β
_{ik}^{2}P _{ki}+C(Q _{0i}+K _{t}β
_{ik}^{2}Q _{ki})]????????????????????(2)In formula (1) and (2); S _{n}The reference capacity of selecting inthe grouping;
S _{i}I inthe grouping is waited level capacity;
β
_{Ik}distribution transformer capacity is S _{i}The time relative datum capacity S _{n}Conversion load factor under each load factor;
β
_{Nk}distribution transformer capacity reference capacity S _{n}The time load factor;
P _{Ik}Average load rate β
in the combination ofdistribution transformer capacity sequence _{Nk}Under the average composite loss of transformer;
P _{0i}distribution transformer capacity is S _{i}Specified unloaded active loss, unit is;
kW;
K _{t}fluctuation of load loss factor generally gets 1.05;
P _{Ki}distribution transformer capacity is S _{i}The nominal load active loss, unit is;
kW;
Q _{Ki}distribution transformer capacity is S _{i}Specified unloaded reactive loss, unit is;
kvar;
Cis idle economic equivalent, kW/kvar;
Idle herein economy is when measuring 0.1;Distribution transformer at certain model carries out the capacitance grade sequence optimisation, at first should begin grouping from the minimum capacity grade according to the rated capacity of relevant existing standard defined and calculate; The grouping minimum capacity grade in the normal capacity sequence exactly begins, general 4～
6 is one group, if find in calculating that flex point does not appear in the average composite loss curve of heap(ed) capacity grade in grouping yet, can continue to increase the capacitance grade number in the grouping.Concrete computational methods can be decomposed (2) formula;


2. the method for claim 1 is characterized in that the method for claim 1 is refined as following steps:

(1) the normal capacity grade being divided into groups from low to high, is one group with 4～
6 capacitance grades, at first determines first group, is the reference capacity grade with the lowest capacity grade, can calculate payload under its different loads rate, wherein S according to formula (3) formula _{n}Be reference capacity selected in the grouping;
β
_{Nk}Be distribution transformer capacity reference capacity S _{n}The time load factor, k=1,2,3 S _{Sjnk}Be the actual load size under the reference capacity grade different loads rate;
S _{sjnk}＝
β
_{nk}S _{n}????????????????????(3)(2) calculate composite loss and the mean value thereof under the different loads rate under the reference capacity according to (4) formula; P _{nk}＝
AVERAGE[P _{0n}+K _{t}β
_{nk}^{2}P _{kn}+C(Q _{0n}+K _{t}β
_{nk}^{2}Q _{kn})]????????????(4)Wherein; P _{Nk}Reference capacity grade average load rate β
in the combination ofdistribution transformer capacity sequence _{Nk}Under average composite loss;
P _{0n}distribution transformer reference capacity S _{n}Specified unloaded active loss, unit is;
kW;
K _{t}fluctuation of load loss factor generally gets 1.05;
P _{Kn}distribution transformer reference capacity S _{n}The nominal load active loss, unit is;
kW;
Q _{Kn}distribution transformer reference capacity S _{n}Specified unloaded reactive loss, unit is;
kvar;
Cis idle economic equivalent, kW/kvar;
Idle herein economy is when measuring 0.1;(3) calculate conversion load factor in the grouping, establish that the capacity than the high grade of reference capacity grade is S in the grouping than the high capacitance grade of reference capacity grade _{N+1}, then the conversion load factor of this capacitance grade relative datum capacitance grade can be calculated according to (5) formula;

Specification(s)