1.1 本试验方法涵盖在施加的试验电压下检测和测量绝缘系统端子处的局部放电（电晕）脉冲，包括在试验电压升高和降低时确定局部放电（电晕）起始电压和熄灭电压。该测试方法在确定视在电荷和脉冲重复率等量以及平均电流、二次速率和功率等积分量时也很有用。该测试方法适用于频率从零（直流电压）到2000左右的测试电压 赫兹。 1.2 本试验方法直接适用于可表示为双端电容器的简单绝缘系统 ( 1. ) , ( 2. ) . 2. 1.3 本试验方法也适用于（分布参数）绝缘系统，如高压电缆。必须考虑这种系统中的衰减和反射现象。 有关电缆、变压器和旋转机械的分布参数系统的更多信息，请参见参考文献 ( 1- 9 ) . （见AEIC CS5-87、IEEE C57 113-1991、IEEE C57 124-1991和IEEE 1434-2005。） 1.4 该测试方法可应用于多端绝缘系统，但精度有一定损失，尤其是在涉及感应绕组绝缘的情况下。 1.5 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 第节给出了具体的预防说明 8. 和 14 . 1.6 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 绝缘系统中工作电压下局部放电（电晕）的存在有可能导致绝缘材料寿命显著缩短。一些材料比其他材料更容易受到此类放电损伤。可以使用测试方法研究该特性 D2275 . 5.2 表面上固体绝缘中局部放电（电晕）的存在可能表明存在内腔。局部放电试验在设计和检查模制、层压和复合绝缘以及电缆、电容器、变压器、套管、定子线棒和旋转机器等样品时非常有用 ( 1- 9 ) , ( 13 ) , ( 12 ) . 另见AEIC CS5-87、ICEA T-24-380、IEEE 48、IEEE C57 113-1991、IEEE C57 124-1991和IEEE 1434-2005。 5.3 局部放电（电晕）起始电压和熄灭电压用于确定绝缘系统在没有此类放电的情况下运行的极限电压。熄灭电压通常大大低于起始电压。当工作电压低于起始电压但高于熄灭电压时，瞬态过电压可能会引发放电，然后继续放电，直到电压降至熄灭电压以下。起始电压和熄灭电压取决于许多因素，包括温度和电压变化的速率。在电压下一段时间后，放电可能以不均匀和不可预测的方式开始和停止，特别是对于某些材料中空腔内的放电，尤其是如果形成的放电降解产物是导电的 ( 1. ) , ( 5. ) . 5.4 局部放电的幅值（脉冲高度）表示其在绝缘系统中耗散的能量量。局部放电幅值和脉冲率有助于估计劣化产生的速率或速率变化。 5.5 一般来说，局部放电的发生与固体绝缘材料的基本特性没有直接关系，但通常是由于气体遮挡或绝缘系统中类似缺陷或不连续性的应力过大引起的。局部放电可能发生在导线或端子等位置，而不会对绝缘系统的主要部分造成任何危险。

1.1 This test method covers the detection and measurement of partial discharge (corona) pulses at the terminals of an insulation system under an applied test voltage, including the determination of partial discharge (corona) inception and extinction voltages as the test voltage is raised and lowered. This test method is also useful in determining quantities such as apparent charge and pulse repetition rate together with such integrated quantities as average current, quadratic rate, and power. This test method is useful for test voltages ranging in frequency from zero (direct voltage) to approximately 2000 Hz. 1.2 This test method is directly applicable to a simple insulation system that can be represented as a two-terminal capacitor ( 1 ) , ( 2 ) . 2 1.3 This test method is also applicable to (distributed parameter) insulation systems such as high-voltage cable. Consideration must be given to attenuation and reflection phenomena in this type of system. Further information on distributed parameter systems of cables, transformers, and rotating machines will be found in Refs ( 1- 9 ) . (See AEIC CS5-87, IEEE C57 113-1991, IEEE C57 124-1991, and IEEE 1434-2005.) 1.4 This test method can be applied to multi-terminal insulation systems, but at some loss in accuracy, especially where the insulation of inductive windings is involved. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precaution statements are given in Sections 8 and 14 . 1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 The presence of partial discharges (corona) at operating voltage in an insulation system has the potential to result in a significant reduction in the life of the insulating material. Some materials are more susceptible to such discharge damage than others. This characteristic can be investigated using Test Method D2275 . 5.2 The presence of partial discharges (corona) in an apparently solid insulation is a potential indication of the existence of internal cavities. Partial discharge tests have been useful in the design and inspection of molded, laminated, and composite insulation, as well as specimens in the form of cables, capacitors, transformers, bushings, stator bars, and rotating machines ( 1- 9 ) , ( 13 ) , ( 12 ) . See also AEIC CS5-87, ICEA T-24-380, IEEE 48, IEEE C57 113-1991, IEEE C57 124-1991, and IEEE 1434-2005. 5.3 Partial discharge (corona) inception and extinction voltages are used in the determination of the limiting voltage at which an insulation system will operate free of such discharges. The extinction voltage is often substantially lower than the inception voltage. Where the operating voltage is below the inception voltage but above the extinction voltage, it is possible that a transient over-voltage will initiate discharges which then continue until the voltage is lowered below the extinction voltage. Inception and extinction voltages depend upon many factors, including temperature and the rate at which the voltage is changed. After a time at a voltage, it is possible that discharges will start and stop in a nonuniform and unpredictable fashion, especially for discharges within cavities in certain materials, in particular if the discharge degradation products formed are conductive ( 1 ) , ( 5 ) . 5.4 The magnitude (pulse height) of a partial discharge is an indication of the amount of energy that it dissipates in the insulation system. Partial discharge magnitude and pulse rate are useful in estimating the rate, or change of rate, at which deterioration is produced. 5.5 In general, the occurrence of partial discharges is not directly related to the basic properties of a solid insulating material, but usually results from overstressing of gaseous occlusions or similar imperfections or discontinuities in an insulating system. It is possible that partial discharges will originate at locations such as on the leads or terminals without resulting in any hazard within the main part of the insulation system.