Investigation on the Arc Ignition Characteristics and Energy Absorption of Liquid Metal Current Limiter Based on Self-Pinch Effect

Abstract

The GaInSn liquid metal current limiter based on the fluid pinch effect has broad application prospects due to its particular properties. However, the limited rated current and ability of power dissipation are the critical problems for its wide application. Firstly, the temperature distribution of the liquid metal current limiter (LMCL) was obtained by experiments with a rated current of 1 kA and the arc ignition phenomenon was observed with 1.5 kA, which indicates that the rated current is mainly limited by the arc rather than the high temperature compared to the traditional switchgears. Furthermore, an improved method is proposed by adding the paralleled pure resistance, impedance or another LMCL element to protect the setup from the fault energy concentration in the setup. The problem of a slower arc voltage increasing rate can be solved by adding a paralleled impedance with suitable parameters. Finally, the current limiting properties based on the improved method were investigated and the alternating oscillating current was found between two paralleled LMCL elements owing to their deviation of arc ignition in reality.

A novel fault current limiter topology design based on liquid metal current limiter

“…Figure 2 shows the principle of the LMCL's liquid metal self-pinch effect. According to [3,8,[18][19][20], the magnetic flux density B and Lorentz force F mag in the channel cross section are greater than those outside the channel, because when the current flows through the liquid metal, the current density is not uniformly distributed along the axial direction. However, when a short-circuit fault occurs, the current and F mag of the liquid metal in the channel rise significantly, hence the column of liquid metal shrinks rapidly under the current action to form depressions.…”

“…It had taken the combination of the advantages of LMCL and the crisis of the power grid to bring about the adoption of LMCL as a new current-limiting technology with tremendous potential. Several groups have carried out a lot of research and achieved many excellent results [8][9][10].…”

“…Aiming at use in the highvoltage direct-current field, reference [7] proposed a new type of FCL and its coordination schemes with a direct-current circuit breaker. Referring to [8], a method was proposed of adding the paralleled pure resistance, impedance or another LMCL element to protect the setup from the fault energy concentration in the setup. References [11][12][13][14] analyzed the physical process of the pre-arc self-pinching mechanism by building an LMCL simulation model of the insulating wall.…”

Research on the energy consumption mechanism and characteristics of the gallium indium tin liquid metal arcing process

“…GaInSn liquid metal has excellent properties such as high conductivity, high thermal conductivity and a low melting point. In the field of electrical engineering, the research into liquid metals currently focuses on microfluidic switches [4][5][6], energy storage [7][8][9][10][11] and current limiting [12,13]. Relevant simulations and experiments have been carried out for GaInSn.…”

Study on the formation of arc plasma on the resistive wall liquid metal current limiter

“…With the rapid expansion of modern power grids and the continuous operation of large-capacity groups, the system structure has been complex, the short-circuit fault forms have become diverse, and the short-circuit current has increased. Simultaneously, the requirements for various electrical equipment are more stringent, which has become a difficult problem that restricts the development of the power grid [1][2][3][4].…”