Object: To approach the reliability of high-frequencycurrent acting upon the devitalization of dental pulp, the safety and clinical effect for peripheral tissues of root tip.
目的：探讨高频电流对牙髓失活作用的可靠性、对根尖周围组织的安全性及临床疗效。
2
The method employed high-frequency voltage-signal injection to make motor form a high-frequencycurrent-vector, of which the negative component current contained rotor space-position information.
该方法采用高频电压载波注入方式形成高频电流矢量，其负序分量包含了转子空间位置信息。
3
The paper introduces the technique feature and the operation principle of chip CS5460A, and its application in high-accuracy power frequency voltage, current, power, power factor, frequency meter.