油浸式电力变压器一般都装设有机械式瓦斯继电器作主保护使用。但是,由于存在可靠性差、速动性低以及阈值整定困难等问题,目前广泛应用的瓦斯保护不正确动作时有发生。伴随着变压器内部故障的发生,故障电能将转换为热能、动能等其他形...油浸式电力变压器一般都装设有机械式瓦斯继电器作主保护使用。但是,由于存在可靠性差、速动性低以及阈值整定困难等问题,目前广泛应用的瓦斯保护不正确动作时有发生。伴随着变压器内部故障的发生,故障电能将转换为热能、动能等其他形式能量,而油箱内部压强骤升是电气网络故障显著、快速的非电量表征。为此,建立变压器油箱内、外部故障压力特征模型,根据故障与非故障状态下油箱内部压力特征差异构造基于压力特征的变压器数字式保护。以63 MVA/220 k V变压器为例,仿真验证不同运行情况下的保护动作特性,结果表明:新原理正确可行,动作速度较传统瓦斯保护显著提高,能够灵敏甄别绕组小匝数短路故障,且本质上不受励磁涌流影响。展开更多
In this work,experimental and theoretical studies were carried out on arc-induced bubble dynamic behaviors in insulation oil.Direct experimental evidence indicated that the arc-induced bubble experiences pulsating gro...In this work,experimental and theoretical studies were carried out on arc-induced bubble dynamic behaviors in insulation oil.Direct experimental evidence indicated that the arc-induced bubble experiences pulsating growth rather than a continuous expansion.Furthermore,a theoretical model and numerical calculation method were proposed,which revealed the dynamic mechanism of bubble growth.Good agreement between the theoretical results and experimental observations verified the general correctness and feasibility of the proposed method.展开更多
文摘油浸式电力变压器一般都装设有机械式瓦斯继电器作主保护使用。但是,由于存在可靠性差、速动性低以及阈值整定困难等问题,目前广泛应用的瓦斯保护不正确动作时有发生。伴随着变压器内部故障的发生,故障电能将转换为热能、动能等其他形式能量,而油箱内部压强骤升是电气网络故障显著、快速的非电量表征。为此,建立变压器油箱内、外部故障压力特征模型,根据故障与非故障状态下油箱内部压力特征差异构造基于压力特征的变压器数字式保护。以63 MVA/220 k V变压器为例,仿真验证不同运行情况下的保护动作特性,结果表明:新原理正确可行,动作速度较传统瓦斯保护显著提高,能够灵敏甄别绕组小匝数短路故障,且本质上不受励磁涌流影响。
基金supported by National Natural Science Foundation of China(No.51807151)。
文摘In this work,experimental and theoretical studies were carried out on arc-induced bubble dynamic behaviors in insulation oil.Direct experimental evidence indicated that the arc-induced bubble experiences pulsating growth rather than a continuous expansion.Furthermore,a theoretical model and numerical calculation method were proposed,which revealed the dynamic mechanism of bubble growth.Good agreement between the theoretical results and experimental observations verified the general correctness and feasibility of the proposed method.