Abstract: The present application relates to tunnel monitoring and measuring, more particularly, to a quick fixing device for measuring a tunnel peripheral convergence and an application method thereof. A right-angle steel sheet includes a first steel sheet and a second steel sheet which are vertically fixed with each other. The fastener vertically penetrates the first steel sheet, and an explosive powder loading portion on a rear end of the fastener is arranged at a side of the second steel sheet. The reinforcing steel sheet is respectively connected to the first steel sheet and the second steel sheet as a reinforcing bar. A through hole is provided on the reinforcing spacer, through which the reinforcing spacer is sleeved on the fastener. The reinforcing spacer is arranged between the explosive powder loading portion on the rear end of the fastener and the first steel sheet.

Abstract: The present application relates to tunnel monitoring and measuring, more particularly, to a quick fixing device for measuring a tunnel peripheral convergence and an application method thereof. A right-angle steel sheet includes a first steel sheet and a second steel sheet which are vertically fixed with each other. The fastener vertically penetrates the first steel sheet, and an explosive powder loading portion on a rear end of the fastener is arranged at a side of the second steel sheet. The reinforcing steel sheet is respectively connected to the first steel sheet and the second steel sheet as a reinforcing bar. A through hole is provided on the reinforcing spacer, through which the reinforcing spacer is sleeved on the fastener. The reinforcing spacer is arranged between the explosive powder loading portion on the rear end of the fastener and the first steel sheet.

Abstract: The present provided a novel protection method of direct current converter valve thyristor in discontinuous current mode. In normal operation, the thyristor of converter valve will be triggered normally when thyristor anode and cathode voltage is positive, and thyristor electronics (TE) send pulse. If the discontinuous current happens, the current will over zero and the thyristor will cut off. After that if the forward voltage appears again, the voltage will be too great, more than the thyristor voltage capability. If the thyristor is not triggered immediately, the thyristor will be damaged probably. To ensure converter valve work normally in discontinuous current mode of the direct current transmission system, TE design has automatic re-trigger function to protect thyristor in discontinuous current mode; in triggering interval when forward voltage is up to +100V the thyristor will be re-triggered to ensure thyristor and system work safely and reliably.