一种轻小型四极杆质谱仪射频电源的研制

四极杆结构是四极杆质谱仪的核心结构，由射频电源分别施加两组高压高频信号进行驱动，利用电场的变化和输入离子的质荷比差异对离子进行筛选。针对四极杆质谱仪小型化的研制需求，以信号调制模块、放大模块、反馈电路和直流模块为基本构型，设计了一种应用于轻小型四极杆质谱仪的射频驱动电源。经实际测试，该电源可以在谐振频率1.33 MHz、扫描频率10 Hz的输入条件下，输出峰 峰值电压最高可达3.33 kV的调幅射频高压信号并驱动四极杆结构，扫描切换时间不高于1 ms。射频电源输出信号稳定、波动小、交直比的波动为0.1%。该射频电源相较于常规的四极杆射频电源具有更高的扫描范围，体积小巧，功耗仅30 W，接口简单，有较高的实用价值。

Development of a Miniaturized Ratio Frequency Power for Quadrupole Mass SpectrometerL

Mass spectrometer is a scientific instrument used to analyze and detect. It is widely used in scientific research fields such as physics, chemistry, geology, astronomy, etc. Most of the mass spectrometers on the market are very expensive, cumbersome and inconvenient. Quadrupole mass spectrometer selects the specific ions by the varying electric field and the different charge-to-mass between multiple ions. And because of the magnetic field constraints are not required, quadrupole mass spectrometer can be miniaturized. The miniaturized experimental equipment can be applied in the non-laboratory environment or the space science satellite. Quadrupole structure can be driven by radio frequency (RF) signals which are composed of two sets of high voltage and high frequency signals. These signals produce an alternating electric field in the quadrupole. According to the demand of miniaturized quadrupole spectrometer, an RF power supply was developed. The power supply was composed of modulation module, amplifier circuit module, feedback module, and DC module. In addition, a small transformer with specially design was used to generate high voltage. The skeleton of the transformer was PTFE whose diameter and length were 40 mm, 100 mm respectively. The amplitude signal and the sine signal were multiplied in the modulation module. An op-amp structure which could amplify signals from 0 V to the maximum with a linear envelope was used in the circuit. The feedback circuit module was used to adjust the waveform of output signals and reduced the error of the UV ratio. In a test, the power supply could output an adjustable amplitude RF high-voltage that the peak-to-peak voltage was up to 3.33 kV and the switch time was less than 1 ms. The power supply drove the quadrupole structure under the input condition of a resonant frequency of 1.33 MHz which could be changed by the input port and the scanning frequency of 10 Hz. The output of the RF power supply was observed by an oscilloscope (Tektronix-MDO3024) with a dedicated probe (Tektronix-P6015A). The RF power supply has good working stability and small interference. According to the data analysis obtained from the oscilloscope, the error of the UV ratio of the power supply is about 0.1% and the power supply can work reliably for a long time. Compared with traditional power supply, the instrument has a higher scanning range, smaller size, and lower power consumption, which is 35 W. In general, the design has high practical value and meets design requirements.