Pe = n × P × (εe/ε)^0.5 = 1.00 × 25.00 × (0.20 / 1.00)^0.5 = 11.18kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 0.35 × 11.18 × 1000 / (1.732 × 380 × 0.60) = 9.91A
Pjs = Kx × Pe = 0.35 × 11.18 = 3.91kW Qjs = Pjs × tgφ = 3.91 × 1.33 = 5.22kvA (5)100m高扬程水泵
Kx = 0.75，Cosφ = 0.8，tgφ = (1 - Cosφ^2)^0.5/ Cosφ = (1 - 0.8^2)^0.5 / 0.8 = 0.75 Pe = n × P × (εe/ε)^0.5 = 1.00 × 20.00 × (0.40 / 0.40)^0.5 = 20.00kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 0.75 × 20.00 × 1000 / (1.732 × 380 × 0.80) = 28.49A
Pjs = Kx × Pe = 0.75 × 20.00 = 15.00kW Qjs = Pjs × tgφ = 15.00 × 0.75 = 11.25kvA (6)白炽灯
Kx = 1，Cosφ = 1，tgφ = (1 - Cosφ^2)^0.5/ Cosφ = (1 - 1^2)^0.5 / 1 = 0.00 Pe = n × P × (εe/ε)^0.5 = 40.00 × 0.10 × (0.40 / 0.40)^0.5 = 4.00kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 1.00 × 4.00 × 1000 / (1.732 × 380 × 1.00) = 6.08A Pjs = Kx × Pe = 1.00 × 4.00 = 4.00kW Qjs = Pjs × tgφ = 4.00 × 0.00 = 0.00kvA (7)3号分箱计算负荷
用电设备同期使用系数Kx=0.80；
Ijs = Kx × ΣPe / (1.732 × Ue × Cosφ) = 0.80 × 64.37 × 1000 / (1.732 × 380 × 0.75) = 104.33A；
同时要求分箱用电负荷不得小于分箱下用电设备最大计算负荷的1.1倍，故： Ijs = max{104.33,1.1×max(0.52,0.72,51.84,9.91,28.49,6.08,)} = 104.33A 4、4号分箱设备用电负荷 (1)钢筋调直机
Kx = 0.65，Cosφ = 0.7，tgφ = (1 - Cosφ^2)^0.5/ Cosφ = (1 - 0.7^2)^0.5 / 0.7 = 1.02 Pe = n × P × (εe/ε)^0.5 = 1.00 × 11.00 × (0.40 / 0.40)^0.5 = 11.00kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 0.65 × 11.00 × 1000 / (1.732 × 380 × 0.70) = 15.52A
Pjs = Kx × Pe = 0.65 × 11.00 = 7.15kW Qjs = Pjs × tgφ = 7.15 × 1.02 = 7.29kvA
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(2)钢筋切断机
Kx = 0.65，Cosφ = 0.7，tgφ = (1 - Cosφ^2)^0.5/ Cosφ = (1 - 0.7^2)^0.5 / 0.7 = 1.02 Pe = n × P × (εe/ε)^0.5 = 2.00 × 5.50 × (0.40 / 0.40)^0.5 = 11.00kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 0.65 × 11.00 × 1000 / (1.732 × 380 × 0.70) = 15.52A
Pjs = Kx × Pe = 0.65 × 11.00 = 7.15kW Qjs = Pjs × tgφ = 7.15 × 1.02 = 7.29kvA (3)钢筋弯曲机
Kx = 0.65，Cosφ = 0.7，tgφ = (1 - Cosφ^2)^0.5/ Cosφ = (1 - 0.7^2)^0.5 / 0.7 = 1.02 Pe = n × P × (εe/ε)^0.5 = 2.00 × 3.00 × (0.40 / 0.40)^0.5 = 6.00kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 0.65 × 6.00 × 1000 / (1.732 × 380 × 0.70) = 8.47A Pjs = Kx × Pe = 0.65 × 6.00 = 3.90kW Qjs = Pjs × tgφ = 3.90 × 1.02 = 3.98kvA (4)数控钢筋调直切断机
Kx = 0.2，Cosφ = 0.65，tgφ = (1 - Cosφ^2)^0.5/ Cosφ = (1 - 0.65^2)^0.5 / 0.65 = 1.17 Pe = n × P × (εe/ε)^0.5 = 1.00 × 28.00 × (0.40 / 0.40)^0.5 = 28.00kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 0.20 × 28.00 × 1000 / (1.732 × 380 × 0.65) = 13.09A
Pjs = Kx × Pe = 0.20 × 28.00 = 5.60kW Qjs = Pjs × tgφ = 5.60 × 1.17 = 6.55kvA (5)木工圆锯
Kx = 0.65，Cosφ = 0.6，tgφ = (1 - Cosφ^2)^0.5/ Cosφ = (1 - 0.6^2)^0.5 / 0.6 = 1.33 Pe = n × P × (εe/ε)^0.5 = 1.00 × 5.50 × (0.40 / 0.40)^0.5 = 5.50kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 0.65 × 5.50 × 1000 / (1.732 × 380 × 0.60) = 9.05A Pjs = Kx × Pe = 0.65 × 5.50 = 3.58kW Qjs = Pjs × tgφ = 3.58 × 1.33 = 4.77kvA (6)木工圆锯
Kx = 0.65，Cosφ = 0.6，tgφ = (1 - Cosφ^2)^0.5/ Cosφ = (1 - 0.6^2)^0.5 / 0.6 = 1.33 Pe = n × P × (εe/ε)^0.5 = 1.00 × 3.00 × (0.40 / 0.40)^0.5 = 3.00kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 0.65 × 3.00 × 1000 / (1.732 × 380 × 0.60) = 4.94A Pjs = Kx × Pe = 0.65 × 3.00 = 1.95kW Qjs = Pjs × tgφ = 1.95 × 1.33 = 2.60kvA
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(7)木工平刨床
Kx = 0.65，Cosφ = 0.6，tgφ = (1 - Cosφ^2)^0.5/ Cosφ = (1 - 0.6^2)^0.5 / 0.6 = 1.33 Pe = n × P × (εe/ε)^0.5 = 1.00 × 3.00 × (0.40 / 0.40)^0.5 = 3.00kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 0.65 × 3.00 × 1000 / (1.732 × 380 × 0.60) = 4.94A Pjs = Kx × Pe = 0.65 × 3.00 = 1.95kW Qjs = Pjs × tgφ = 1.95 × 1.33 = 2.60kvA (8)套丝切管机
Kx = 0.2，Cosφ = 0.65，tgφ = (1 - Cosφ^2)^0.5/ Cosφ = (1 - 0.65^2)^0.5 / 0.65 = 1.17 Pe = n × P × (εe/ε)^0.5 = 6.00 × 2.00 × (0.40 / 0.40)^0.5 = 12.00kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 0.20 × 12.00 × 1000 / (1.732 × 380 × 0.65) = 5.61A
Pjs = Kx × Pe = 0.20 × 12.00 = 2.40kW Qjs = Pjs × tgφ = 2.40 × 1.17 = 2.81kvA (9)4号分箱计算负荷
用电设备同期使用系数Kx=0.80；
Ijs = Kx × ΣPe / (1.732 × Ue × Cosφ) = 0.80 × 79.50 × 1000 / (1.732 × 380 × 0.75) = 128.84A；
同时要求分箱用电负荷不得小于分箱下用电设备最大计算负荷的1.1倍，故： Ijs = max{128.84,1.1×max(15.52,15.52,8.47,13.09,9.05,4.94,4.94,5.61,)} = 128.84A
5、总箱计算负荷
总的计算负荷计算，总配电箱用电设备同期使用系数取Kx = 0.80 总的有功功率： Pjs = Kx×ΣPjs = 0.80 × 116.87 = 93.50kW 总的无功功率： Qjs = Kx×ΣQjs = 0.80 × 143.02 = 114.42kvar
总的视在功率： Sjs = (Pjs^2 + Qjs^2)^0.5 = (93.50 × 93.50 + 114.42 × 114.42)^0.5 = 147.76kVA
总的计算电流计算：Ijs = Sjs × 1000 /(1.732 × Ue) = 147.76 × 1000 / (1.732 × 380) = 224.51A 同时要求总箱下计算负荷不得小于分箱计算负荷的1.1倍，故：
Ijs = max{224.51,1.1×max(72.17,97.24,104.33,128.84,)} = 224.51A
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总分2
1、1号分箱设备用电负荷 (1)塔式起重机
Kx = 0.7，Cosφ = 0.65，tgφ = (1 - Cosφ^2)^0.5/ Cosφ = (1 - 0.65^2)^0.5 / 0.65 = 1.17 Pe = n × P × (εe/ε)^0.5 = 1.00 × 32.80 × (0.40 / 0.25)^0.5 = 41.49kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 0.70 × 41.49 × 1000 / (1.732 × 380 × 0.65) = 67.89A
Pjs = Kx × Pe = 0.70 × 41.49 = 29.04kW Qjs = Pjs × tgφ = 29.04 × 1.17 = 33.95kvA (2)1号分箱计算负荷
用电设备同期使用系数Kx=0.80；
Ijs = Kx × ΣPe / (1.732 × Ue × Cosφ) = 0.80 × 41.49 × 1000 / (1.732 × 380 × 0.75) = 67.24A；
同时要求分箱用电负荷不得小于分箱下用电设备最大计算负荷的1.1倍，故： Ijs = max{67.24,1.1×max(67.89,)} = 74.68A 2、2号分箱设备用电负荷 (1)施工升降机
Kx = 0.3，Cosφ = 0.6，tgφ = (1 - Cosφ^2)^0.5/ Cosφ = (1 - 0.6^2)^0.5 / 0.6 = 1.33 Pe = n × P × (εe/ε)^0.5 = 1.00 × 60.00 × (0.40 / 0.40)^0.5 = 60.00kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 0.30 × 60.00 × 1000 / (1.732 × 380 × 0.60) = 45.58A
Pjs = Kx × Pe = 0.30 × 60.00 = 18.00kW Qjs = Pjs × tgφ = 18.00 × 1.33 = 24.00kvA (2)2号分箱计算负荷
用电设备同期使用系数Kx=0.80；
Ijs = Kx × ΣPe / (1.732 × Ue × Cosφ) = 0.80 × 60.00 × 1000 / (1.732 × 380 × 0.75) = 97.24A；
同时要求分箱用电负荷不得小于分箱下用电设备最大计算负荷的1.1倍，故： Ijs = max{97.24,1.1×max(45.58,)} = 97.24A 3、3号分箱设备用电负荷 (1)交流电焊机
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Kx = 0.5，Cosφ = 0.4，tgφ = (1 - Cosφ^2)^0.5/ Cosφ = (1 - 0.4^2)^0.5 / 0.4 = 2.29 Pe = n × P × (εe/ε)^0.5 = 1.00 × 38.60 × (0.50 / 1.00)^0.5 = 27.29kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 0.50 × 27.29 × 1000 / (1.732 × 380 × 0.40) = 51.84A
Pjs = Kx × Pe = 0.50 × 27.29 = 13.65kW Qjs = Pjs × tgφ = 13.65 × 2.29 = 31.27kvA (2)对焊机
Kx = 0.35，Cosφ = 0.6，tgφ = (1 - Cosφ^2)^0.5/ Cosφ = (1 - 0.6^2)^0.5 / 0.6 = 1.33 Pe = n × P × (εe/ε)^0.5 = 1.00 × 25.00 × (0.20 / 1.00)^0.5 = 11.18kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 0.35 × 11.18 × 1000 / (1.732 × 380 × 0.60) = 9.91A
Pjs = Kx × Pe = 0.35 × 11.18 = 3.91kW Qjs = Pjs × tgφ = 3.91 × 1.33 = 5.22kvA (3)100m高扬程水泵
Kx = 0.75，Cosφ = 0.8，tgφ = (1 - Cosφ^2)^0.5/ Cosφ = (1 - 0.8^2)^0.5 / 0.8 = 0.75 Pe = n × P × (εe/ε)^0.5 = 1.00 × 20.00 × (0.40 / 0.40)^0.5 = 20.00kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 0.75 × 20.00 × 1000 / (1.732 × 380 × 0.80) = 28.49A
Pjs = Kx × Pe = 0.75 × 20.00 = 15.00kW Qjs = Pjs × tgφ = 15.00 × 0.75 = 11.25kvA (4)白炽灯
Kx = 1，Cosφ = 1，tgφ = (1 - Cosφ^2)^0.5/ Cosφ = (1 - 1^2)^0.5 / 1 = 0.00 Pe = n × P × (εe/ε)^0.5 = 40.00 × 0.10 × (0.40 / 0.40)^0.5 = 4.00kW
Ij1 = Kx × Pe / (1.732 × Ue × cosφ) = 1.00 × 4.00 × 1000 / (1.732 × 380 × 1.00) = 6.08A Pjs = Kx × Pe = 1.00 × 4.00 = 4.00kW Qjs = Pjs × tgφ = 4.00 × 0.00 = 0.00kvA (5)3号分箱计算负荷
用电设备同期使用系数Kx=0.80；
Ijs = Kx × ΣPe / (1.732 × Ue × Cosφ) = 0.80 × 62.47 × 1000 / (1.732 × 380 × 0.75) = 101.25A；
同时要求分箱用电负荷不得小于分箱下用电设备最大计算负荷的1.1倍，故： Ijs = max{101.25,1.1×max(51.84,9.91,28.49,6.08,)} = 101.25A
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