SPD在楼宇内的分布优化配置及与其他开断设备配合研究
摘要
SPD（Surge Protection Device，电涌保护器/浪涌保护器）是在建筑物配电线路中常用的保护装置，其主要作用是抑制雷电和操作过电压，它可以在不切断线路的情况下吸收冲击能量，减小冲击幅值，从而保护其保护范围内的线路和设备。
本文的研究目的是完成SPD在建筑物内配电线路上的布置优化，并考虑其与开断保护设备的配合。为了研究SPD在建筑物内的布置优化，本文主要研究了建筑物内线路及负载对于冲击的响应。根据线路及负载的冲击响应情况，SPD可以在建筑物内更有针对性的进行布置，这样可以提高SPD的安装效率。通过研究SPD与其他开断器件的配合，可以调整SPD的安装，以减少其他开断器件发生误动作的可能性。
本文研究了建筑物内的配电线路，通过使用PEEC（Partial ElementEquivalent Circuit，部分元等效电路法）方法，完成了线路在冲击状况下的PEEC方法建模，并通过与现有商业软件的计算结果对比，验证了算法正确性。
在现有楼宇内雷电研究中，很少的研究会考虑到真实有损大地对于冲击在传输线路上的影响，也还未有研究考虑到受真实有损大地影响的线路在受到感应冲击影响时的状况。因此本文在使用PEEC方法研究楼宇内线路的基础上，进一步增加考虑了大地对于冲击在线路传输中以及相互间感应的影响，建立了考虑有损大地情况下的建筑物线路PEEC模型。通过此模型，可以计算出当雷电冲击侵入到建筑物内的电力线路后，线路对于冲击的响应状况，包括冲击的传输过程以及冲击在线路间感应的过程。
当线路上有冲击存在时，建筑物中的负载同样会对冲击产生响应并反过来对冲击产生影响，因此，在考虑建筑物内电涌保护器布置的时候，必须要考虑到负载的影响。由于电子类负载（指非电阻电容电感类负载）在建筑物中的大量使用，而这类负载在冲击情况下的模型不能简单使用线性元件等效，因此这类负载在冲击情况下的建模十分有必要。本文选取了建筑物内常用的两种电子类负载（照明用日光灯及开关电源类负载），研究了其在冲击状况下的建模，完成了建模的实验验证，并将模型带入PEEC模型进行计算。
RCD（Residual Current Device，漏电流保护器），是常用的防止漏电的开断保护器件，一般安装在负载和SPD保护器之间，主要用来防止漏电事故或单相接地事故，同时也能起到一定的防止浪涌冲击的作用。RCD能够在检测到故障发生时迅速切断线路以保护负载，但也存在因为线路的扰动冲击而误动作的可能。雷电冲击可能导致RCD的动作，同时SPD保护之后的剩余冲击也可能导致RCD的误动作，因此，雷击保护为目的的电涌保护器布置优化，还需要考虑SPD与RCD之间的配合。本文研究了RCD在非工频工况下的工作状况，包括非工频正弦电流、非对称电流、冲击电流情况下的动作情况。通过以上研究，可以对SPD的安装提供参考，以保证RCD不会由于SPD保护不当而断开后部电路造成负载停电，同时也减小由于SPD和RCD安装配合失当导致RCD发生误动作的可能性。
将线路模型和负载模型结合，可以完整的分析雷电从入侵建筑物后传输、感应，直到最后对负载产生影响的过程。在此基础上，加入考虑SPD和RCD之间的配合，即可完成SPD在建筑物内的布置优化。
Surge Protection Device (SPD) is an appliance designed toprotect electrical devices from voltage spikes, SPD attempts to limitthe voltage supplied to an electric device by either blocking or byshorting to ground any unwanted voltages above a safe threshold.
In this thesis, the purpose is to research on optimize allocation ofSPD in buildings and SPD coordination with other surge protectors.Surge response of transmission line in buildings, loads impact by surgeand SPD coordination with other protectors are researched.
Transmission line theory is discussed in the thesis. Partial ElementEquivalent Circuit (PEEC) method is used in the discussion for modelingthe electromagnetic behavior of arbitrary three-dimensional electricalinterconnection structures. Numerical calculation of the PEEC is derivedin the thesis and vilified by comparing calculation result with theATP/EMTP software.
Ground effect is considered in the PEEC model. Measurement of thesoil parameters is discussed and measurement results are used in thePEEC model. PEEC transmission line theory based on Dyadic Green Function (DGF) over real ground is derived. Importance of ground effectis proved due to calculation result comparison between perfect groundsituation and real ground situation. Vertical line and horizontal line modelare derived by the author and SPD installation is discussed in each model.
Load is another important factor which may have great effect in thesurge transmission. Electric loads are now widely used in buildings,which cannot model with linear elements. Two typical electric loads(ballast and SMPS) are discussed in surge situation. Surge models of thetwo loads are given in the thesis and verified by comparing with testresult of the laboratory experiments.
Residual Current Device (RCD) is widely used in buildings toprevent accidental electrocution. Besides it can trip when fault situationdetected. Noise tripping of RCD also may happened when surge passthrough. Experimental investigations into operating characteristics ofRCD are done under unbalanced current. The unbalanced current includethee harmonic current, ground fault current, and surge current. A testingsystem is set up in the laboratory, and the minimum values of the currentcausing RCD samples to trip are recorded. The research can help with thecoordination of SPD and RCD.
Whole surge model of the building is derived and verified bycomparing with the experiment result, which can help with the SPD allocation optimization. Coordination with RCD should also beconsidered when considering the SPD allocation optimization.
本文的研究目的是完成SPD在建筑物内配电线路上的布置优化，并考虑其与开断保护设备的配合。为了研究SPD在建筑物内的布置优化，本文主要研究了建筑物内线路及负载对于冲击的响应。根据线路及负载的冲击响应情况，SPD可以在建筑物内更有针对性的进行布置，这样可以提高SPD的安装效率。通过研究SPD与其他开断器件的配合，可以调整SPD的安装，以减少其他开断器件发生误动作的可能性。
本文研究了建筑物内的配电线路，通过使用PEEC（Partial ElementEquivalent Circuit，部分元等效电路法）方法，完成了线路在冲击状况下的PEEC方法建模，并通过与现有商业软件的计算结果对比，验证了算法正确性。
在现有楼宇内雷电研究中，很少的研究会考虑到真实有损大地对于冲击在传输线路上的影响，也还未有研究考虑到受真实有损大地影响的线路在受到感应冲击影响时的状况。因此本文在使用PEEC方法研究楼宇内线路的基础上，进一步增加考虑了大地对于冲击在线路传输中以及相互间感应的影响，建立了考虑有损大地情况下的建筑物线路PEEC模型。通过此模型，可以计算出当雷电冲击侵入到建筑物内的电力线路后，线路对于冲击的响应状况，包括冲击的传输过程以及冲击在线路间感应的过程。
当线路上有冲击存在时，建筑物中的负载同样会对冲击产生响应并反过来对冲击产生影响，因此，在考虑建筑物内电涌保护器布置的时候，必须要考虑到负载的影响。由于电子类负载（指非电阻电容电感类负载）在建筑物中的大量使用，而这类负载在冲击情况下的模型不能简单使用线性元件等效，因此这类负载在冲击情况下的建模十分有必要。本文选取了建筑物内常用的两种电子类负载（照明用日光灯及开关电源类负载），研究了其在冲击状况下的建模，完成了建模的实验验证，并将模型带入PEEC模型进行计算。
RCD（Residual Current Device，漏电流保护器），是常用的防止漏电的开断保护器件，一般安装在负载和SPD保护器之间，主要用来防止漏电事故或单相接地事故，同时也能起到一定的防止浪涌冲击的作用。RCD能够在检测到故障发生时迅速切断线路以保护负载，但也存在因为线路的扰动冲击而误动作的可能。雷电冲击可能导致RCD的动作，同时SPD保护之后的剩余冲击也可能导致RCD的误动作，因此，雷击保护为目的的电涌保护器布置优化，还需要考虑SPD与RCD之间的配合。本文研究了RCD在非工频工况下的工作状况，包括非工频正弦电流、非对称电流、冲击电流情况下的动作情况。通过以上研究，可以对SPD的安装提供参考，以保证RCD不会由于SPD保护不当而断开后部电路造成负载停电，同时也减小由于SPD和RCD安装配合失当导致RCD发生误动作的可能性。
将线路模型和负载模型结合，可以完整的分析雷电从入侵建筑物后传输、感应，直到最后对负载产生影响的过程。在此基础上，加入考虑SPD和RCD之间的配合，即可完成SPD在建筑物内的布置优化。
Surge Protection Device (SPD) is an appliance designed toprotect electrical devices from voltage spikes, SPD attempts to limitthe voltage supplied to an electric device by either blocking or byshorting to ground any unwanted voltages above a safe threshold.
In this thesis, the purpose is to research on optimize allocation ofSPD in buildings and SPD coordination with other surge protectors.Surge response of transmission line in buildings, loads impact by surgeand SPD coordination with other protectors are researched.
Transmission line theory is discussed in the thesis. Partial ElementEquivalent Circuit (PEEC) method is used in the discussion for modelingthe electromagnetic behavior of arbitrary three-dimensional electricalinterconnection structures. Numerical calculation of the PEEC is derivedin the thesis and vilified by comparing calculation result with theATP/EMTP software.
Ground effect is considered in the PEEC model. Measurement of thesoil parameters is discussed and measurement results are used in thePEEC model. PEEC transmission line theory based on Dyadic Green Function (DGF) over real ground is derived. Importance of ground effectis proved due to calculation result comparison between perfect groundsituation and real ground situation. Vertical line and horizontal line modelare derived by the author and SPD installation is discussed in each model.
Load is another important factor which may have great effect in thesurge transmission. Electric loads are now widely used in buildings,which cannot model with linear elements. Two typical electric loads(ballast and SMPS) are discussed in surge situation. Surge models of thetwo loads are given in the thesis and verified by comparing with testresult of the laboratory experiments.
Residual Current Device (RCD) is widely used in buildings toprevent accidental electrocution. Besides it can trip when fault situationdetected. Noise tripping of RCD also may happened when surge passthrough. Experimental investigations into operating characteristics ofRCD are done under unbalanced current. The unbalanced current includethee harmonic current, ground fault current, and surge current. A testingsystem is set up in the laboratory, and the minimum values of the currentcausing RCD samples to trip are recorded. The research can help with thecoordination of SPD and RCD.
Whole surge model of the building is derived and verified bycomparing with the experiment result, which can help with the SPD allocation optimization. Coordination with RCD should also beconsidered when considering the SPD allocation optimization.
引文
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