Electrical calculation of VL-0.38kV using the reduced cost method.

Drawing up design schemes and calculation of lines of VL-0.38 kV.

Figure 5.1. Calculation scheme of the line VL-0.38kV for KTP-1

Electrical calculation of VL-0.38kV using the reduced cost method.

We choose the line routes so as not to clutter up the roadway and do without additional supports when arranging entrances to buildings.

In accordance with the selected line routes, we will draw up a design scheme in Figure 5.1, indicating the active power factor of consumers, the number of calculated sections, and the length of the sections.

The calculation of outgoing lines is carried out by the method of additions. The essence of this method is to determine the active design power, reactive and equivalent apparent powers. Then, by equivalent power, we determine the cross section of the wires of the line. We determine the voltage loss in the line, given its length. The design power on the line sections is determined by summing the design power passing through this section.

KP.110.302.51.32.014.PZ Sheet K.P. Change Sheet Document No. Signed the date The summation of loads is performed by the method of additions using table 4.4 [RUM, p. 30, table 4.4]. The power factor is taken according to the prevailing load in the design section according to table 4.5 [RUM, p. 31, table 4.5]. Let’s execute for the prevailing maximum loads P В . Total design power of the line section: s= ; (5.1) where: – active design power of the line section, kW; – load power factor. Equivalent power: ; (5.2) where: – coefficient of growth dynamics; for agricultural consumers = 0.7; Having determined the equivalent power, according to the table of economic loads for the main and additional wire sections of the 0.4 kV overhead line [RUM, pp. 123-124, adj. 4], we select the cross-sectional area and the number of wires for each section of the line, for the II climatic region on ice (the thickness of the ice wall is b = 10 mm). We check the accepted brands of wires according to the condition of permissible voltage loss. The voltage loss in the line sections is determined by the formula: L∙ (5.3) where: – specific voltage loss, % per 1 kV×A×m×10 [RUM, p. 32, Table 4.6] L is the length of the estimated section of the line, m; KP.110.302.51.32.014.PZ Sheet K.P. Change Sheet Document No. Signed the date Line – 1 Section 3-2: Determine the linear value in section 3-2: =2.74 [kW] Determine the calculated maximum load in section 2-3: [kVA]; Determine the equivalent load [kVA]; We determine the number, brand and cross-section of the wires F main in section 2-3 (Appendix 4, RUM p. 125): we accept the wire F main = 3A25 + A25; We determine the specific voltage loss DU ud in section 3-2 (Table 4.6, RUM p. 32): = 0.9085[% per 1 kV×A×m×10 ]; We determine the voltage loss DU uch at account 3-2, with the selected sections: =0.9085∙ 2.946∙40∙10 -3 =0.107[%]. Plot 5-3: =2.74+1.645=4.385 [kW] [kVA]; [kVA]; We accept the wire F main = 3A ∙ 25 + A ∙ 25; = 0.9085[% per 1 kV×A×m×10 ]; determine the voltage loss in this section: =0.9085∙4.715∙68∙10 -3 =0.291[%]. KP.110.302.51.32.014.PZ Sheet K.P. Change Sheet Document No. Signed the date Plot 7-5: =6.702+2.631+3.702=13.03 [kW] [kVA]; [kVA]; we accept the wire F main u003d 3A ∙ 25 + A ∙ 25; = 0.9085[% per 1 kV×A×m×10 ]; determine the voltage loss in this section: =0.9085∙14.01∙50∙10 -3 =0.636[%]. Plot 9-7: =13.03+3.702+3.6=20.332 [kW] [kVA]; [kVA]; accept wire F main = 3A∙25 + A∙25; = 0.9085[% per 1 kV×A×m×10 ]; determine the voltage loss in this section: =0.9085∙21.86∙20∙10 -3 =0.397[%]. Plot 10-9: =20.332+0.6=20.93 [kW] [kVA]; [kVA]; accept wire F main = 3A∙25 + A∙25; = 0.9085[% per 1 kV×A×m×10 ]; determine the voltage loss in this section: =0.9085∙22.5∙70∙10 -3 =1.43[%]. KP.110.302.51.32.014.PZ Sheet K.P. Change Sheet Document No. Signed the date Plot L1-10 =20.93+4.2=25.13 [kW] [kVA]; [kVA]; accept wire F main = 3A∙25 + A∙25; = 0.899[% per 1 kV×A×m×10 ]; determine the voltage loss in this section: =0.899∙27.9∙110∙10 -3 =2.76[%]. Check: We determine the value of the voltage loss from the power source to the most remote point, that is, on account L1-10: DU L1 = + + + + + ; ; – satisfies the condition. KP.110.302.51.32.014.PZ Sheet K.P. Change Sheet Document No. Signed the date Line-2 Section 16-15 =50 [kW] [kVA]; [kVA]; we accept the wire F main = 3A ∙ 50 + A ∙ 50; = 0.486[% per 1 kV×A×m×10 ]; determine the voltage loss in this section: =0.486∙64.1∙40∙10 -3 =1.246[%]. Plot L2-15 =50+30.2=80.2 [kW] [kVA]; [kVA]; we accept the wire F main = 3A ∙ 50 + A ∙ 50; = 0.495[% per 1 kV×A×m×10 ]; determine the voltage loss in this section: =0.495∙94.35∙40∙10 -3 =1.866[%]. Check: We determine the value of the voltage loss from the power source to the most remote point, that is, on account L2-15: DU L1 = + ; ; ; – satisfies the condition. KP.110.302.51.32.014.PZ Sheet K.P. Change Sheet Document No. Signed the date Line-3 Section 6-1 =2.74 [kW] [kVA]; [kVA]; accept wire F main = 3A∙16 + A∙16; = 1.359[% per 1 kV×A×m×10 ]; determine the voltage loss in this section: =1.359∙2.94∙70∙10 -3 =0.279[%]. Plot 13-6 + =8+3.702+1.645=13.195 [kW] [kVA]; [kVA]; accept wire F main = 3A∙16 + A∙16; = 1.359[% per 1 kV×A×m×10 ]; determine the voltage loss in this section: =1.359∙14.188∙56∙10 -3 =1.079[%]. Plot 14-13 + =50+8.017+3=61.01 [kW] [kVA]; [kVA]; we accept the wire F main = 3A ∙ 50 + A ∙ 50; = 0.444[% per 1 kV×A×m×10 ]; determine the voltage loss in this section: =0.444∙61.63∙50∙10 -3 =1.368[%]. KP.110.302.51.32.014.PZ Sheet K.P. Change Sheet Document No. Signed the date Plot L3-14 =61.01+1.2=62.21 [kW] [kVA]; [kVA]; we accept the wire F main = 3A ∙ 50 + A ∙ 50; = 0.444[% per 1 kV×A×m×10 ]; determine the voltage loss in this section: =0.444∙62.83∙15∙10 -3 =0.418[%]. Check: We determine the value of the voltage loss from the power source to the most remote point, that is, on account L3-14: DU L3 = + ; ; ; – satisfies the condition. KP.110.302.51.32.014.PZ Sheet K.P. Change Sheet Document No. Signed the date Table 5.1 – The results of the electrical calculation of the wires of the overhead line – 0.38 kV.

Line section Design parameters Quantity mark and wire section Section length Voltage loss
R cos phi S S E NF Ф + F 0 L ΔU UD ΔU UCH
kW kVA kVA mm 2 m %/kV∙A m 10 -3
TP type KTP-160/10/0.4-90-U1
Line – 1
2-3 2.74 0.93 2.946 2.06 3А-25+А-25 0.9085 0.107
5-3 4.385 0.93 4.715 3.3 3А-25+А-25 0.9085 0.291
7-5 12.1 0.93 13.01 9.1 3А-25+А-25 0.9085 0.590
9-7 19.25 0.93 20.698 14.49 3А-25+А-25 0.9085 0.376
10-9 19.85 0.93 21.344 14.94 3А-25+А-25 0.9085 1.357
L1-10 24.05 0.9 26.72 18.7 3А-25+А-25 0.9085 2.67
Line – 2
15-16 0.78 64.1 44.87 3А-50+А-50 0.486 1.246
L2-15 80.2 0.85 94.35 66.05 3А-50+А-50 0.495 1.866
Line – 3
6-1 2.74 0.93 2.94 2.06 3A-16+A-16 1.359 0.195
13-6 13.195 0.93 14.188 9.93 3A-16+A-16 1.359 1.079
14-13 61.01 0.99 61.63 43.14 3А-50+А-50 0.444 1.368
L3-14 62.21 0.99 62.83 43.98 3А-50+А-50 0.444 0.418

KP.110.302.51.32.014.PZ Sheet K.P. Change Sheet Document No. Signed the date CONTENTS Introduction. 1. Characteristics of the power supply facility; substantiation of the category of consumers in terms of reliability of power supply (according to a given plan). 2. Determination of electrical loads at the inputs to the premises and objects. 3. Assessing the quality of voltage from consumers. 3.1 Calculation of permissible voltage losses in the electrical network, the adopted power supply system. 4. Choice of quantity and installation location of TS 10/0.4 kV. 4.1 Rationale for choosing the type of TP, 4.2 Design of TP. 4.3 Electrical diagram of the TP and the functional purpose of the elements of the TP circuit. 5. Electrical calculation of lines 380/220 V (0.38/0.22 kV). 5.1 Selection of the number and routes of 0.38 / 0.22 kV lines. 5.2 Drawing up design schemes for 0.38 kV overhead lines. 5.3 Electrical calculation of 0.38 kV overhead lines using the reduced cost method. 5.3.1 Determination of the calculated equivalent powers for sections of overhead lines. 5.3.2 Selection of cross-sectional area and number of wires. 5.3.3 Calculation of voltage losses in the wires of VL-0.38 kV. 5.4 Calculation of outdoor lighting wires. 6. The design of the 380/220 V network. 7. The choice of protection for 0.38/0.22 kV lines and checking its operation in case of short circuits. 8. Reliability of power supply of objects. 8.1 Reservation (specifically for the objects of the plan). 9. Measures for labor protection during the construction of a 0.38 / 0.22 kV network. 10. Issues of ecology and environmental protection during the construction of a 0.38 / 0.22 kV network. 11. Conclusion and conclusions. 12. List of references. KP.110.302.51.32.014.PZ Sheet K.P. Change Sheet Document No. Signed the date

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