Influence of Nonlinear Processes in Soils on the Impulse Resistance of Grounding Electrodes

The article presents the results of laboratory studies of nonlinear processes during the flow of pulsed currents into moistened soil from electrodes modelling grounding devices of electric power facilities. A methodology for studying the pulse parameters of grounding devices has been developed and a laboratory stand and a generator measuring system have been developed on which these investigation were performed. The experiments were carried out on three types of electrodes at voltages of 20 - 50 kV and pulse durations from units to hundreds of microseconds. The article presents the combined results of optical and oscillographic studies. It is shown that the cause of the formation of spark channels during the nonlinear spreading of the pulsed current in the soil, when there is a sharp decrease in the grounding resistance, is the ionization-overheating instability that occurs when the current density on the electrode is greater than the critical one. The development of instability leads to an inhomogeneous current distribution and the appearance of spark channels. On the basis of experimental data, the current-voltage characteristics of the electrodes are obtained.

Grounding Fault Model of Low Voltage Direct Current Supply and Utilization System for Analyzing the System Grounding Fault Characteristics

Grounding fault analysis is of vital importance for low voltage direct current (LVDC) supply and utilization systems. However, the existing DC grounding fault model is inappropriate for LVDC supply and utilization system. In order to provide an appropriate assessment model for the DC grounding fault impact on the LVDC supply and utilization system, an LVDC supply and utilization system grounding fault model is proposed in this paper. Firstly, the model is derived by utilizing capacitor current and voltage as the system state variable, which considers the impact of the converter switch state on the topology of the fault circuit. The variation of system state parameters under various fault conditions can be easily obtained by inputting system state data in normal conditions as the initial value. Then, a model solution algorithm for the proposed model is utilized to calculated the maximum fault current, the system maximum fault current with different grounding resistance is simple to acquired based on the solution algorithm. The calculation results demonstrate that grounding resistance and structure of LVDC supply and utilization system have remarkable impacts on the transient current. The effectiveness of the proposed model is verified in PSCAD/EMTDC. The simulation results indicate that the proposed method is appropriate for the system fault analysis under various fault conditions with different grounding resistance and the proposed model can offer theoretical guidance for system fault protection.

(In)coherent subjects? The politics of conceptualising resistance in the UK asylum system

Many accounts of resistance within systems of migration control pivot upon a coherent migrant subject, one that is imbued with political agency and posited as oppositional to particular forms of sovereign power. Drawing upon ethnographic research into the role of creativity within the UK asylum system, I argue that grounding resistance with a stable, coherent and agentic subject, aligns with oppositional narratives (of power vs resistance), and thereby risks negating the entangled politics of the (in)coherence of subject formation, and how this can contain the potential to disrupt, disturb or interrupt the practices and premise of the UK asylum system. I suggest that charity groups and subjects should not be written out of narratives of resistance apriori because they engage with ‘the state’: firstly, because to argue that there is a particular form that resistance should take is to place limits around what counts as the political; and secondly, because to ‘remain oppositional’ is at odds with an (in)coherent subject. I show how accounts which highlight a messy and ambiguous subjectivity, could be bought into understandings of resistance. This is important because as academics, we too participate in the delineation of the political and what counts as resistance. In predetermining what subjects, and forms of political action count as resistance we risk denying recognition to those within this system.

Pemanfaatan Drainase (Saluran) Air Bekas Limbah Rumah Tangga sebagai Solusi untuk Penurunan Resistansi Pentanahan (Grounding)

This study aims to anticipate a high value of grounding resistance by utilizing drainage or waste water from household waste as a planting medium to reduce the value of grounding resistance. The research method used is an experimental method of testing and measuring at field locations. In this study, a round rod electrode is coated with copper, namely testing with one electrode rod and two electrode rods that are installed in parallel or better known as the use of a driven rod. The results showed a decrease in the value of the grounding resistance where the average value for 1 grounding rod was 18.32 ohms and 11.82 ohms for the measurement of 2 grounding rods installed in parallel. From the test results, there was a decrease in the resistance value of 59.52% for 1 electrode rod and a 51.75% decrease for 2 electrode rods, where the decrease in the resistance value in the field was caused by factors of water, humidity and used water minerals from household waste. In conclusion, housing with reddish yellow podzolic soil that is clay (high soil resistance) by utilizing water drainage is a solution to reduce grounding resistance. Keywords: Resistance, Drainage, Grounding (Grounding)

The Right to Wage Private Wars of Subsistence

Some philosophers have recently argued for the revisionist just war doctrine that individuals can have the right to initiate war in defense of their human rights when their government fails in its duty to protect them. It was a central tenet of early modern just war theory, too, that when judicial recourse is not available, individuals are entitled to enforce their basic rights by force of war. How should we conceptualize such remedial rights to secure basic rights by armed force? And where to fit such rights within ethical theories of war? This chapter explores these questions by critically contrasting two ways to ground individual rights to wage so-called “private subsistence wars”: via “modern” duties of global justice and via “old” rights of necessity. I argue that the right-of-necessity model—for better or worse—can sidestep problems of indeterminate and underdetermined moral liability by grounding resistance rights in enforceable rights (of subsistence) rather than in enforceable duties (of global justice). My analysis thus charts normative implications of dispensing with the legitimate authority condition by analyzing what it means for rights and duties to be enforceable.

A novel fault section locating method based on distance matching degree in distribution network

Fault section location of a single-phase grounding fault is affected by the neutral grounding mode of the system, transition resistance, and the blind zone. A fault section locating method based on an amplitude feature and an intelligent distance algorithm is proposed to eliminate the influence of the above factors. By analyzing and comparing the amplitude characteristics of the zero-sequence current transient components at both ends of the healthy section and the faulty section, a distance algorithm with strong abnormal data immune capability is introduced in this paper. The matching degree of the amplitude characteristics at both ends of the feeder section are used as the criterion and by comparing with the set threshold, the faulty section is effectively determined. Finally, simulations using Matlab/Simulink and PSCAD/EMTDC show that the proposed section locating method can locate the faulty section accurately, and is not affected by grounding mode, grounding resistance, or the blind zone.