CN202267704U - Detecting circuit for over-current shake of high-voltage pulse power supply - Google Patents

Abstract

The utility model discloses a detecting circuit for the over-current shake of high-voltage pulse power supply, which comprises a high-voltage pulse circuit and a reference signal generating circuit, wherein a discharging main loop of the high-voltage pulse circuit and the output end of the reference signal generating circuit are connected to a voltage comparator through a current mutual inductor. The detecting circuit disclosed by this utility model can detect small over-current shake generated during 0-pi/4 and 3pi/4-pi, thus, the reliability of power supply is improved.

Description

The excess current shake testing circuit that is used for high-voltage pulse power source

Technical field

The utility model belongs to simulation electronic and field of power electronics, relates to a kind of excess current shake testing circuit that is used for high-voltage pulse power source particularly.

Background technology

Existing nearly all excimer laser power supply all adopts C-L-C resonant charging mode, so the overcurrent waveform of electric current is a half-sinusoid in the switch.The common practices of holding circuit is as shown in Figure 1, and the reference signal of the sinusoidal same fixed level of actual current signal compares, and when actual current shake during greater than the level value of this reference signal, thinks that then circuital current is excessive.The shortcoming of this way is: because electric current is a sinusoidal signal; In the time of in during a less shake occurs in 0～π/4 and 3 π/4～π; Because less actual current jitter value is still less than this fixed level, therefore this manner of comparison then can't detect the shake of actual current.

The utility model content

The purpose of the utility model is to provide a kind of excess current shake testing circuit that is used for high-voltage pulse power source.

For realizing above-mentioned purpose; The excess current shake testing circuit that is used for high-voltage pulse power source that the utility model provides; Comprise a high-voltage pulse circuit and a reference signal generation circuit; Wherein, high-voltage pulse circuit discharge major loop is connected to a voltage comparator through the output terminal of a current transformer and reference signal generation circuit.

Described testing circuit, wherein voltage comparator is MAX942, LM339 or LM393.

Described testing circuit, wherein the current amplitude of high-voltage pulse circuit is the 55-65% of the current amplitude of reference signal generation circuit.

Described testing circuit, wherein the current waveform cycle of high-voltage pulse circuit is the 85-90% in the current waveform cycle of reference signal generation circuit.

Interior less excess current was shaken during the testing circuit that the utility model provides can detect and occur in 0～π/4 and 3 π/4～π, thereby the reliability of power supply is provided.

Description of drawings

Fig. 1 is the synoptic diagram of known technology.

Fig. 2 is the testing circuit structural representation of the utility model.

Fig. 3 is the embodiment that the utility model detects the electric current shake.

Fig. 4 is the periodic signal synoptic diagram that the utility model high-voltage pulse circuit C-L-C discharges and recharges.

Fig. 5 compares with reference current signal when actual current signal is shaken in the utility model detection method, and electric circuit inspection has been the synoptic diagram of dither flow.

Embodiment

Below in conjunction with accompanying drawing the utility model is described in detail.

Please combine shown in Figure 2; The testing circuit of the utility model is made up of known high-voltage pulse circuit A and known reference signal generation circuit B; High-voltage pulse circuit A discharge major loop is connected to the input end (the utility model employing be known voltage comparator, like MAX942 or LM339 or LM393 etc.) of a voltage comparator D respectively through the output terminal of a current transformer C and reference signal generation circuit B.

Two capacitor C 1 among the high-voltage pulse circuit A and the energy delivery between the C2 are the basic element circuits of output pulses generation source circuit, and the introducing of the inductance L 1 among Fig. 2 is that to produce the resonant charging process necessary.When being charged to certain voltage on the capacitor C 1, the switch closure conducting, the electric flux on the capacitor C 1 shifts to capacitor C 2 through inductance L 1.Capacitor C 1 voltage reduces, capacitor C 2 voltages risings (as shown in Figure 4).Duration of charging on the capacitor C 2 is by capacitor C 1, inductance L 1, capacitor C 2 common decisions.

The inductance value of L1 is actually the decision of pulse transformer leakage inductance, is a fixed value.Select the value of suitable capacitor C 1 and C2, through formula:

$t=\mathrm{\π}\sqrt{L1\·C}(c=\frac{C1C2}{C1+C2})$

Calculate the current waveform cycle t (being example in this example with t=4.5us) of an actual current.Current waveform on the side circuit is to be the half-sinusoid (as shown in Figure 3) about 4.5us in the cycle like this.

For reference signal generation circuit, the voltage cycle signal that discharges and recharges that utilizes C-L to form, according to formula:

$t=\mathrm{\π}\sqrt{\mathrm{CL}}$

Select the value of suitable capacitance C and inductance L, making reference signal generation circuit voltage wave period is the half-sinusoid (as shown in Figure 3) about t=5us.

The amplitude of high-voltage pulse circuit A and reference signal generation circuit B is selected as shown in Figure 3; The sinusoidal wave amplitude of reference signal generation circuit B is slightly larger than the sinusoidal wave amplitude of high-voltage pulse circuit A, gathers C-L-C discharge main circuit current (being actual current signal) through current transformer C and compares with the sinusoidal wave amplitude of reference signal generation circuit B.If less excess current shake (marking part like Fig. 5 dotted line) takes place in during 0～π/4 and 3 π/4～π; Then the output level of voltage comparator D is by high step-down; Can real-time being detected, reaching the purpose that current protection is reported to the police, thereby the reliability of power supply is provided.

Claims (4)

1. an excess current that is used for high-voltage pulse power source is shaken testing circuit; It is characterized in that; Comprise a high-voltage pulse circuit and a reference signal generation circuit; Wherein, high-voltage pulse circuit discharge major loop is connected to a voltage comparator through the output terminal of a current transformer and reference signal generation circuit.

2. testing circuit according to claim 1 is characterized in that, wherein voltage comparator is MAX942, LM339 or LM393.

3. testing circuit according to claim 1 is characterized in that, wherein the current amplitude of high-voltage pulse circuit is the 55-65% of the current amplitude of reference signal generation circuit.

4. testing circuit according to claim 1 is characterized in that, wherein the current waveform cycle of high-voltage pulse circuit is the 85-90% in the current waveform cycle of reference signal generation circuit.

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