عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Since the local quench which induces electro-thermal instability if a local energy input exceeds a certain threshold called minimum quench energy (MQE), the normal zone propagates along the superconductor. Therefore, the rate of the normal zone spreading as a quench propagation velocity (νq) is an important factor in the quench detection and protection. This paper focuses on the measurement of νq as a self-protection parameter in a short sample of a high temperature superconducting Bi-2223/AgMg tape by applying the localized heat pulses, and MQE as a superconducting stability criterion. In addition, the current dependences of MQE and νq were verified in which by increasing the transport current, the rate of decreasing of MQE and the rate of increasing of νq were measured. These experiments have been done in nitrogen vapor without applying any magnetic field.
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