CN2084252U - Field effect power tube type high voltage dc-to ac converting power supper for mine - Google Patents

Abstract

The utility model provides a field effect power tube type high voltage DC-to AC converting power supply for mines, which is composed of a power conversion circuit, a controlling circuit, a timing starting circuit, and a latching protection circuit. The power conversion circuit, the controlling circuit, the timing starting circuit, and the latching protection circuit are assembled in a hermetically sealed housing. The utility model carries out a new design for critical circuits, in particular to the circuits which adopt field effect power tubes, so the design of the circuits of the utility model is reasonable and compact, the size is small, the weight is light, the reliability is high, and failure rate is low. The utility model adopts the hermetically sealed housing, so the utility model can effectively prevent dust and damp, avoid sparking which is caused by short circuits, etc.

Description

Field effect power tube type high voltage DC-to AC converting power supper for mine

The utility model belongs to the potential device technical field that is transformed to low-voltage dc power supply by high-voltage DC power supply.

Under the present domestic coal mine on the stringing electrical locomotive for used D.C. regulated power supplies of electric equipment such as illuminations, electric whistle, carrier communication, all be that high voltage direct current from the overhead wire is through the inverter conversion.The used high-voltage inverted power supply of current mine is owing to be subjected to the influence of factors such as circuit design, key components and process structure, ubiquity failure rate height, and poor reliability, fault-free continuous operating time are shorter, and shortcoming such as dust and moisture poor performance.This has brought a lot of difficulties to ordinary maintenance, has a strong impact on downhole safety production.

The objective of the invention is to develop a kind of reliability height, failure rate is low, easy to maintenance, can dust and moisture, guarantee the novel high-pressure inverter of Safety of Coal Mine Production.

The high-voltage inverted power supply complete machine of mining fet power cast is by high pressure input circuit, power conversion circuit, control circuit, timing starting circuit, current rectifying and wave filtering circuit, sampling circuit of pressure-stabilizing, latch-up protection circuit be formed by connecting (seeing accompanying drawing 1).

Below just relevant Key Circuit division with the present invention as follows.

1, power conversion circuit

This circuit is the hinge that connects hi-lo circuit, and continuous operation is under high voltage, high-power state.What select for use in the existing high-voltage inverted power translation circuit is that the high back-pressure transistor of high frequency is as power switch pipe, because this pipe power less (less than 50 watts), desire obtains high-power output, need two in parallel uses, its driving, apolegamy be difficulty relatively, and secondary-breakdown phenomenon takes place easily, and this is one of emphasis that causes existing inverter potential faults.Adopted high frequency, high withstand voltage, high-power (single power 125 watts) in the power conversion circuit of the present invention, from the fet power pipe of ballast (no secondary-breakdown phenomenon) as power switch pipe.Use the low leakage inductance of the well-designed coiling of EC type magnetic core of high saturation magnetic induction, the switch transformer B of anti-saturation simultaneously ₁Replaced existing leakage inductance big, efficient is low, start moment or at high temperature occur magnetic saturation easily and then jeopardize the switch transformer of the common FERRITE CORE coiling of power switch pipe.Selecting for use of above key components and parts for improving whole aircraft reliability, reduced fault and played key effect.In order to control two fet power pipes, this circuit has been introduced driving transformer B ₂This transformer directly connects control circuit and power conversion circuit, and the ALT pulse of control circuit output is through transformer B ₂Isolated variable directly drives two fet power pipes and takes turns conducting.

This circuit is by fet power pipe T ₂, T ₃, switch transformer B ₁, driving transformer B ₂And capacitor C ₁₄～C ₂₂, R ₂₇～R ₃₃Semibridge system power conversion circuit Deng the element composition.(seeing accompanying drawing 2).Its operation principle is by driving transformer B ₂Be connected with control circuit and controlled by it.Integrated pulse width modulator IC in control circuit ₁11 pin, 14 pin alternately export driving pulse after, by driving transformer B ₂Isolation drive makes T ₂, T ₃Conducting in turn.Like this at B ₁Primary coil produces the high voltage pulse of alternate, through switch transformer B ₁Isolated variable is at B ₁Secondary coil obtains required pulse low pressure and supplies with current rectifying and wave filtering circuit output dc low-voltage, has just finished thus and will import the function that high direct voltage is transformed into dc low-voltage.

2, control circuit

This circuit is the emphasis circuit that direct relation circuitry structure and complete machine performance.Adopted the novel integrated PWM controller IC that is suitable for Driving Field effect power tube in this circuit ₁This circuit also has except that having the required various basic circuits of separated exciting pulse-width modulation switching power supply: the control of (1) adjustable dead time has prevented the common-mode conducting of power switch pipe effectively; (2) both-end output Driving Field effect power tube makes complete machine have switching speed faster; (3) protection of pulse one by one of voltage control cut-out makes the design of complete machine protective circuit very simple.

This circuit is mainly by an integrated PWM controller IC who is suitable for Driving Field effect power tube ₁And peripheral cell is formed (seeing accompanying drawing 3).IC ₁9 pin meet R ₄, C ₁Constitute the error amplifier compensating circuit; R ₈Be output pulse Dead Time control element; C ₇Be submissive starting capacitance; 16 pin output reference voltages 5.1V; 15 pin are IC ₁Input supply terminal; R ₁₁, D ₁, D ₂, C ₈With after the output voltage voltage stabilizing as IC ₁Supply voltage; 10 pin are overvoltage g-load sampling voltage input, and after 10 pin voltages were greater than 1 volt, the output pulse of 11 pin, 14 pin just was cut off.The operation principle of this circuit is, by timing element C ₆, R ₉With IC ₁Internal oscillator produces the higher-order of oscillation, handles through internal circuit, alternately exports modulating pulse at 11 pin, 14 pin, is used for the driving power translation circuit.Sampling circuit of pressure-stabilizing adds to IC after output voltage is taken a sample ₁1 pin, compare with inner precision voltage reference, amplification and a series of processing, the modulating pulse of exporting the corresponding pulsewidth opposite with the sampling voltage variation tendency at output 11 pin, 14 pin at last in order to the ON time of change power switch pipe, and then is regulated output voltage.

3, timing starting circuit

Still can reliably start in order to adapt to the variation of down-hole frequent starting and input voltage wide region, this high-voltage inverted power supply has designed timing starting circuit.Promptly connect input voltage, start-up circuit work about 3 seconds, output starting resistor supply control circuit is started working, and is so that the output voltage after starting returns the supply control circuit steady operation, then in these three seconds, start-up circuit quits work, and waits for that start next time.

Regularly starting circuit is by fet power pipe T ₁, one-way SCR CR ₂, CR ₃Voltage-stabiliser tube D ₈, D ₉And resistance R ₁₉-R ₂₆, capacitor C ₁₁～C ₁₂Form (seeing accompanying drawing 4).When the high pressure input circuit is connected, capacitor C ₁₁Begin charging, T ₁Saturation conduction, the output starting resistor is through D ₁₂Add to IC ₁Power end is started working control circuit, this process about 3 seconds, this moment C ₁₁On voltage be charged to D ₉Puncture voltage, make it conducting after, trigger CR ₂, CR ₃Conducting.CR ₂Conducting with C ₁₁On electric charge discharge very soon, for starting the preparation that resets, CR next time ₃Conducting make T ₁End,, finished initiating task so starting resistor disappears.

Except above-mentioned Key Circuit, this high-voltage inverted power supply complete machine has also designed quick output overvoltage overload protecting circuit.During work, in case the output overvoltage g-load occurs, protective circuit triggers the driving pulse of governor circuit rupturing duty translation circuit, and then output voltage is disappeared, and this moment, control circuit lost power supply voltage supplying.And start-up circuit quit work the output of no starting resistor therefore control circuit also quit work, make complete machine enter the latch-up protection state.This blocking protection mode has been avoided the endless loop of the sort of startup-g-load in the general high voltage inverter-protection-startup, can protect power device effectively, avoids the generation of serious accident.

The high-voltage inverted power supply of mining fet power cast has been owing to carried out new design to Key Circuit wherein, and particularly suitable proper for the key components and parts in the circuit makes that this power supply circuitry is reasonable in design, and compactness, reliability are high, and failure rate is low.Through the on-the-spot commerical test that carry out in Datong District mineral bureau four ore deposits April in October, 1989 to nineteen ninety, proved that this machine is fit to the down-hole, produce practical, the reliability height, failure rate is low, and accumulative total is moved more than 140 day, the fault-free continuous operating time reaches more than 90 day, and the user is reflected fine.This power supply complete machine is placed in the hermetic casing, has played the dust and moisture effect effectively.In a word, the output voltage stability height of this supply unit, the electric current and voltage regulating power is strong, good reliability, the fault-free continuous operating time is long, and efficient height, in light weight, and volume is little, is expected to become the renewal product of similar type.

Description of drawings:

Fig. 1 is the high-voltage inverted power supply circuitry of a mining fet power cast block diagram.

Fig. 2 is a power conversion circuit schematic diagram in the high-voltage inverted power supply of mining fet power cast

Among the figure:

C ₁₄、C ₁₅－100μ／400V，C ₁₆、C ₁₇－0.1μ／400V，C ₁₈、C ₁₉－5600P／100V。C ₂₀、C ₂₁－0.01μ／630V，C ₂₂－0.01μ／1kv，

R ₂₇、R ₂₈－200k，R ₂₉、R ₃₀－20Ω，R ₃₁、R ₃₂－100Ω，R ₃₃－47Ω，

T ₂、T ₃－BVZ380，D ₁、D ₂－FR107

Fig. 3 is a control circuit schematic diagram in the high-voltage inverted power supply of mining fet power cast.

Among the figure:

C ₁－3300P／100V，C ₂－0。1μ／100VC ₄－100μ／16V，C ₅－0。1μ／100V，C ₆－0。1μ／100V，C ₇－0。47μ／16V。

R ₄－160k，R ₅－200Ω，R ₆－10k，R ₇－10k，R ₈－20Ω，R ₉－4。3k，R ₁₀－100Ω，R ₁₁－100Ω。

D ₁、D ₂－1N4001，D ₂－2CW58。

Fig. 4 is a timing starting circuit schematic diagram in the high-voltage inverted power supply of mining fet power cast

Among the figure:

C ₁₁－10μ／25V，C ₁₂－0。033μ／100v

R ₁₉－200kΩ，R ₂₀－56Ω，R ₂₁－82k，R ₂₂－100Ω，R ₂₄－240kΩ，R ₂₅－20k，R ₂₆－36k。

D ₈－2CW66，D ₉－2CW60，D ₁₁－2CW58D ₁₂－1N4001，CR ₂－1AM3，CR ₃－1AM3。

T ₁－BUZ331。

Claims (1)

1, the high-voltage inverted power supply of a kind of mining fet power cast is by the high pressure input circuit, and power changes circuit, and control circuit, start-up circuit and current rectifying and wave filtering circuit constitute, and it is characterized in that:

(1) in the power conversion circuit, with high back-pressure, high-power, from ballast fet power pipe as power switch pipe;

(2) introduce switch transformer in the power conversion circuit by the low leakage inductance anti-saturation of the EC type magnetic core coiling of R2KB material;

(3) adopted the integrated PWM controller that is suitable for Driving Field effect power tube in the control circuit;

(4) starting circuit mainly is made of fet power pipe and one-way SCR.

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