CN2241339Y

CN2241339Y - Inductive coupling plasma excitation light source

Info

Publication number: CN2241339Y
Application number: CN 96202000
Authority: CN
Inventors: 夏义峰
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-02-07
Filing date: 1996-02-07
Publication date: 1996-11-27
Anticipated expiration: 2006-02-07

Abstract

The utility model relates to an inductive coupling plasma excitation light source, comprising a box body, a half saturation reactor, a high frequency oscillating circuit, a current feedback sample circuit, a thyristor, a control rectifying circuit, etc., wherein, the inductance L 1 of an oscillation slot in the high frequency oscillating circuit is connected in series with a capacitor C0 and then connected in parallel with a variable capacitor C1 for increasing frequency to 40.68 megahertz, and oscillation intensity is changed via regulating the variable resistor of the grid circuit of a triode. The oscillation circuit adopts a high stabilized device, and frequency stability is smaller than 0.1 %. The negative electrode of a main loop is connected in series with a resistor until ground, current feedback is used for controlling the output of the input of a reactor with stabilized power, and output power stability is smaller than 0.5 %.

Description

The inductively coupled plasma excitation source

The utility model relates to a kind of inductively coupled plasma excitation source.

The inductively coupled plasma excitation source is the critical component in the emission spectrographic analysis, after the sample of element to be measured is stimulated in this light source, sends its characteristic spectral line, and certain element spectral line power to be measured has just been represented the concentration of this element.Therefore, the accuracy of whether stablizing directly influence constituent content to be measured of excitation source.In addition, the frequency of operation of inductively coupled plasma excitation source height and degree of stability also will influence the quality of excitating performance.Detect requirement for adapting to, frequency stability and the output power stability to excitation source all has strict requirement at present.

The purpose of this utility model provides a kind of inductively coupled plasma excitation source, this light source adopts common electronic component just can make oscillation frequency reach 40.68 megahertzes of regulation in the world, and the degree of stability of frequency＜0.1%, the degree of stability of output power＜0.5%.

For achieving the above object, the utility model is by the following technical solutions: excitation source comprises casing and semi-saturation reactor, the current rectifying and wave filtering circuit that boosts, high-frequency oscillating circuits, current feedback sample circuit, reference voltage circuit low-voltage regulated power supply, amplifier, thyristor gating circuit, thyristor control rectification circuit, wherein: have an electric capacity to be connected in series in the tank of high-frequency oscillating circuits with inductance, another variable capacitance is in parallel with them, serial connection one variable resistor in the tickler loop; The current feedback sample circuit is to serial connection one resistance between the ground, a loop in parallel on this resistance at the major loop negative pole; Thyristor control rectification circuit and semi-saturation reactor comprise: be subjected to thyristor, the full-wave rectification loop of pulse transformer control and the direct current winding that is serially connected in semi-saturation reactor in the DC loop, this winding head is joined, reactor exchanges winding and is serially connected in the power transformer input circuit, this winding headtotail.

The utility model is described in further detail below in conjunction with accompanying drawing:

Fig. 1: the utility model circuit block diagram

Fig. 2 a: the utility model circuit theory diagrams

Fig. 2 b: the utility model circuit theory diagrams

Among Fig. 1,1 semi-saturation reactor, reactor output connects the current rectifying and wave filtering circuit 2 that boosts, filtering circuit connects high-frequency oscillating circuits 3 again, negative pole at the current rectifying and wave filtering circuit that boosts connects a feedback sample circuit 4, during this feedback signal input amplifier and the voltage of reference voltage circuit 5 make comparisons, amplify through amplifier 6,8 outputs of control thyristor gating circuit, this output is by pulse transformer control thyristor control rectification circuit 9, thereby change DC current in the semi-saturation reactor dc coil, the output AC voltage of transformer T1 also changes thereupon, has reached the purpose of regulating output power.7 is low-voltage regulated power supply among Fig. 1.

Among Fig. 2 a, the 2b, 220 alternating current input transformer T1 are elementary, T3 is elementary, at elementary half saturable reactor T4, the T5 of connecing of T1, T1 output connects the current rectifying and wave filtering circuit that boosts, it comprises D1, C10, C9, L3, its output connects sense coupling frequency modulation auto-excitation type power oscillating circuit, adopt the metallic ceramics triode, model FU-725U, L1 are the tank coils, internal diameter 26mm, 3 circles, simultaneously also be that coupling forms the working coil of plasma for quartzy torch pipe, C1 is the vacuum tunable capacitor, cooperates with L1 to form tank, wherein CO is connected in series with L1, connects C ₀After, oscillation frequency is reached more than 40 megahertzes, can make frequency adjust to 4068 megahertzes by regulating C1, the variable resistor R2 that adjusting triode grid is connected in series with tickler L2 can change oscillation intensity.Adopt the high stable device in the oscillatory circuit, for example high frequency Leaded Ceramic Disc Capacitor and adopt flat copper strips one point earth can make frequency stability＜0.1.

At the negative pole of the current rectifying and wave filtering circuit that boosts to serial connection 3 Ohmages between the ground, on 3 Ohmages and a loop, regulate feedback quantity by the R10 variable resistor, this loop comprises R10, R23, C11, C30, L8,3 pin of loop signal input proportional amplifier LM308, reference voltage of another input 3 pin is loop R25, R26, the R27 that joins with low-voltage regulated power supply output, and this loop meets a stabilivolt TL431, meets R24, L9, C31 before connecing amplifier.9013 outputs are connected to 6 pin of SDKCO5, regulate thyristor gating circuit pulse signal phase-shifted, change the size of bidirectional triode thyristor conduction angle by pulse transformer T3, thereby have changed the DC current in the thyristor control circuit.

In SDKCO5, the 16th pin is connected to transformer T3 time level (30 volts of voltages), and purpose is to make SDKCO5 output and to control in the rectification circuit thyristor synchronous.

Transformer T3 is elementary two groups of 18 volts of power supplys, and after full-wave rectification D5, D6 and voltage stabilizing 7815,7915, the output burning voltage is supplied with SDKCO5, LM308,9013 and the low tension of reference voltage circuit.

The semi-saturation reactor comprises that two exchange winding, two direct current windings.Wherein exchange the winding headtotail, their lines are in full accord through the number of turn, the direct current winding joins for the head, also be that line is in full accord through the number of turn, in this circuit, represent with T4, T5, the figure medium size represents that coil starts, the direct current winding of reactor be serially connected in thyristor control rectification circuit in the output loop of D2 rectification.T4, T5 adopt iron core: CD type 25 * 50 * 100 (mm) exchanges winding 70 circles+10 circles; Direct current winding 800 circles+100 circles.

Among Fig. 2 a, Fig. 2 b, A, B, C are the lead tie point.

Course of action:

When feeding the not perfectly straight stream voltage of alternating current, T1 primary voltage is 175 volts, can make 3000 volts of voltages of secondary output this moment, be used to light the quartzy torch of inductively coupled plasma excitation source, regulating R27 then convinces thyristor by patient analysis, T4, T5 transformer direct current winding has DC current, because T4, behind the dc magnetization of T5 iron core, output AC voltage increases, T1 just group reaches 215 volts, and secondary 3800 volts, if when output voltage or load variations, by feedback sample voltage and reference voltage relatively, difference by amplifier to thyristor automatically adjust power stability reach＜0.5%.

Claims

1, a kind of inductively coupled plasma excitation source, it comprises casing, electronic circuit, it is characterized in that described electronic circuit comprises: semi-saturation reactor, the current rectifying and wave filtering circuit that boosts, high-frequency oscillating circuits, current feedback sample circuit, reference voltage circuit low-voltage regulated power supply, amplifier, thyristor gating circuit, thyristor control rectification circuit, wherein:

(1) high-frequency oscillating circuits comprises: triode, through tank C0, C1, L1 and positive feedback coil L2, the wherein C of capacitor C 2 coupling ₀Be connected in series with L1, C1 and C0, L1 also connect, and L2 is series resistor R1, variable resistor R2 also;

(2) the current feedback sample circuit comprises: be serially connected in the major loop negative pole to the resistance R between the ground 8, and a loop that is connected in parallel on R8, this loop comprises resistance R 10, R23 inductance L 8;

(3) thyristor control rectification circuit and semi-saturation electric controller comprise: be subjected to thyristor, diode D3, the full-wave rectification D2 of pulse transformer control and the direct current winding that is connected on saturated reactor T4, T5 in the DC loop, this winding head is joined, reactor interchange winding is headtotail, and is serially connected in the input circuit of power transformer T1.