一台三相降压电力变压器一二次绕组均为星形联结 U1N／U2N=10000V／400V。在二次侧做空载试验测得数据为：U2=

大学 2021-06-29 01:58:24 绕组,星形,数据已帮助人

一台三相降压电力变压器，一、二次绕组均为星形联结，U_1N/U_2N=10000V/400V。在二次侧做空载试验，测得数据为：U₂=U_2N=400V，I₂₀=60A，p₀=3800W。在一次侧做短路试验，测得数据为：U_1k=440V，I_1k=I_1N=43.3A，p_k=10900W，室温为20℃。求该变压器的参数(用标幺值表示)。

热搜：三相交流异步电动机能耗制动时定子绕组接

答案解析

难度★★☆ 搜索

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I2N=kI1N=25×43.3=1083A
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根据20℃时在额定电流下的短路试验结果，可得
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进行温度换算。换算到75℃时(铜线变压器)，有
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可近似认为
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