在托卡马克装置中，等离子体环向电流是托卡马克放电运行的最基本参数之一。目前在EAST装置上，用于测量等离子体电流的是罗柯线圈加积分器组合，经由罗柯线圈测量由电流引起的磁通变化率，进行积分处理后得到等离子体电流。对于稳态运行装置，稳态等离子体电流和长时间积分器累计漂移均成该方法无法克服的问题。为了实现托卡马克以及今后聚变堆长时间稳态运行的目标，有必要发展新的等离子体电流测量系统。 光纤电流传感器是近年来随着光纤技术的发展而产生的一种新型电流测量装置，相对原有 的罗柯线圈系统，其最大的优势就是能够实现等离子体电流的稳态测量，同时具有更高的测量 精度，更大的测量范围，更强的抗干扰能力，是托卡马克以及聚变堆稳态运行等离子体电流测 量发展的方向。本项目的研究目标就是在EAST超导托卡马克上研发测量准稳态等离子体电流的 光纤电流传感器系统。

Plasma current is one of basic parameters in tokamak operation. At present, the Rogowski coil is used to measure plasma current on EAST tokamak. The signal obtained from Rogowski coil is sent into integrator, then the output from the integrator is the plasma current. For steady-state or DC plasma current, there is no induced voltage from the Rogowski coil. The drift of integrator will be increased when work for long tiome. So the method cannot be used to measure steady-state or long pulse current. The fibre optic current sensor system will use optical fibres placed around the vacuum vessel to measure the plasma current by means of the Faraday Effect. Compare Rogowski coil, the most advantage of fibre optic current sensor is that it can measure steady-state or DC current. In addition, this kind of sensor has higher measurement accuracy, wider measurement range, better anti-interference ability. The goal of this project is to develop a fibre optic current sensor system on EAST tokamak.