强场和弱场侧超声分子束注入对加料的影响

报道了HL-2A装置最新的实验结果,讨论并研究了超声分子束的注入位置对分子束在等离子体中的消融和穿透的影响,其中包括电离后的分子束粒子在磁场梯度作用和 E × B 漂移下的加速或减速及由此形成的冷通道效应.研究结果表明,磁场梯度和 E × B 漂移对于超声分子束的加料效果、消融和穿透有着重要的作用.强场侧注入可使电离后的电子和离子更深地进入等离子体芯部.这些研究对于更好地理解超声分子束与等离子体的相互作用和优化设计加料系统有一定作用.     

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2006年和2008年分别对HL-2A装置的低混杂波传输系统传输特性进行了冷测量和热测量工作。测量结果表明,冷测量传输率达到了94.05%,四个分路的最大相差为11.09°,功率分配也比较均匀;热测量传输率为76%~95%,但功率分配均匀度较差。另外,热测量功率超过230kW时,传输率有明显下降。     

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介绍了以Siemens S7-300PLC为控制核心的HL-2A装置电子回旋共振加热控制与保护系统的设计与实现。系统采用了基于工业以太网的分布式结构,使用VFC/FVC电路和光纤隔离技术传输高电压/大电流的测量与控制信号,确保了控制系统运行的电气安全性,增强了信号传输过程中的抗干扰能力;加热系统的保护采用基于CPLD/FPGA实现的快速保护技术。实验证明该控制与保护系统具有兼容装置现场强电磁干扰的能力,运行稳定可靠、功能完善并具有良好的扩充性能。     

HL-2A 装置低杂波鉴相器标定与实验研究

用低杂波鉴相器对相位测量系统各通道经进行了相位校准,得到了各通道的相位电压关系曲线,并进行了线性拟合,线性拟合误差小于3°;推导出了相位电压关系表达式,与校准得到的相位电压曲线相比平均误差小于0.7°。该系统已成功用于HL-2A 装置低杂波实验,对4 支速调管的输出相位进行了测量,并得到了放电过程中相位随阴极高压波动的曲线,得出了阴极电压波动2.2%引起相位波动13.8°的结论。     

HL-2A装置电子回旋系统弧光探测器的改进

介绍了HL-2A装置电子回旋共振加热系统打火保护装置的改进。在改进设计过程中,实测了2类光电转换模块、4种型号的运算放大器芯片,定量测量了防自激电容的性能。选择了GGOE-2型光电转换器件,OPA128LM型运算放大器,确定了防自激电容为30pF。制作了30个原型机,满足了2009年HL-2A装置的要求。实验测得响应时间平均值为1.2μs,较改进前方案的小。此弧光探测器能够在不同强度的本底光和复杂电磁环境下稳定工作。     

HL-2A装置ECRH系统的新天线设计

Using the principle of quasi-optic, the new antenna of the electron cyclotron resonant heating(ECRH) system on the tokamak HL-2A has been designed. After being focused by the elliptical mirror and reflected by the plane mirror, 4 68GHz/500kW/1s electron cyclotron wave beams would be injected into the tokamak from one Æ350mm port to accomplish heating to the plasma. Based on the propagating theory of the fundamental Gaussian beam, it is gotten that at the centre of the cross section of the tokamak, the power density of each beam is 158MW•m^-2, and the power density radius, which means that the power density is reduced by a factor 1/e² compared to the power density at the centre of the beam, is 31.7mm. On the mirror, due to the focusing and reflecting, the ohmic loss and diffraction loss of the microwave beams are 0.27% and 0.64%, respectively. By the finite element analysis software ANSYS, some thermal analysis of the mirror have been done. The result shows that the highest temperature increase would be only 0.47℃ under 1s pulse load, so there is no need of any cooling.     

HL—1M装置LHCD系统双管运行及长脉冲实验

通过对ＨＬ－１Ｍ装置的ＬＨＣＤ工程系统的微波耦合天线,传输线,高压调制电源,激励电源,辅电源,冷却系统的改进,实现了双管并联动行和单管长脉冲输,双管输出微波功率８５０ＫＷ,单管长脉冲宽度１０５０ｍｓ,耦合效率达到８５％     

微波激励源方案设计

在托卡马克实验装置上进行等离子体低杂波电流驱动和加热实验，需要输入兆瓦量级的微波功率。这是由多只大功率速调管并联运行而实现的，而这些速调管需要前级微波激励源进行驱动。我们目前使用的微波激励源经过十几年的使用，元器件老化和磨损严重，导致了整个设备工作性能的明显下降，不能满足低杂波电流驱动和加热实验的多管并联运行的实验要求。因此有必要设计一个新的微波激励源，工作部件全部采用固态微波器件，稳幅控制。模块化设计采用多路输出，新增加微波相位多路控制，以满足以后实验中低杂波电流驱动和加热两种不同工作方式的需求。     

The first results of divertor discharge and supersonic molecular beam injection on the HL-2A tokamak

HL-2A tokamak is the first tokamak with divertors in China. The plasma boundary and the position of the striking point on the target plates of the HL-2A closed divertor were simulated by the current filament code and they were in agreement with the diagnostic results in the divertor. Supersonic molecular beam injection (SMBI) system was first installed and tested on the HL-2A tokamak in 2004. In the present experiment low pressure SMBI fuelling on the HL-2A closed divertor was carried out. The experimental results indicate that the divertor was operated in the `linear regime' and during the period of SMB pulse injection into the HL-2A plasma the power density convected at the target plate surfaces was 0.4 times of that before or after the beam injection. It is a useful fuelling method for decreasing the heat load on the neutralizer plates of the divertor.