A medical power supply circuit

Abstract

The embodiment of the present invention discloses a medical power supply circuit, including a rectifier filter module, a PFC module, a first DC / DC module, a second DC / DC module and a drive control module; the correction input end of the PFC module is electrically connected to the rectifier output end of the rectifier filter module, and the PFC module is used to reduce the output voltage of the correction output end and correct the power factor of the output voltage; the input end of the first DC / DC module is electrically connected to the rectifier output end, and the DC voltage output from the rectifier output end is converted; the input end of the second DC / DC module is electrically connected to the correction output end, and the DC voltage at the input end is converted into an AC voltage under the control of the drive control module, and then the AC voltage is converted into a DC voltage and then output from the output end. The embodiment of the present invention can achieve double insulation between the power supply and the human body, ensure the safety of the user, and at the same time improve the insulation level of the power supply to meet the growing demand for medical power supplies.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of power supply technology, and in particular to a medical power supply circuit. Background Art

[0002] With the improvement of living standards, people have put forward higher requirements for the safety and comfort of medical treatment. In addition to biocompatibility, tertiary medical care must also ensure that the 220V AC current driven by the power adapter is sufficiently safe when it contacts human muscles and blood vessels.

[0003] The maximum insulation voltage provided by medical power supplies on the market is 4000V, which cannot meet the growing demand for medical power supplies and safety. In addition, the isolation power supply of existing technology does not have good heat dissipation and has a low cost-performance ratio. Summary of the invention

[0004] The embodiment of the present invention provides a medical power supply circuit to achieve double insulation between a power supply and a human body, thereby ensuring the safety of a user and improving the insulation level of the power supply.

[0005] The medical power supply circuit includes: a rectifier and filter module, a PFC module, a first DC / DC module, a second DC / DC module and a drive control module;

[0006] The rectification and filtering module comprises a rectification input terminal and a rectification output terminal, the rectification input terminal is connected to an AC voltage, and the rectification and filtering module is used to convert the AC voltage into a DC voltage;

[0007] The PFC module comprises a correction input terminal and a correction output terminal, the correction input terminal is electrically connected to the rectifier output terminal, and the PFC module is used to reduce the output voltage of the correction output terminal and correct the power factor of the output voltage;

[0008] The first DC / DC module includes an input end and an output end, the input end of the first DC / DC module is electrically connected to the rectifier output end, and the first DC / DC module converts a DC voltage output by the rectifier output end and outputs the DC voltage from the output end of the first DC / DC module;

[0009] The second DC / DC module comprises an input end and an output end, the input end of the second DC / DC module is electrically connected to the correction output end, and the second DC / DC module is used to convert the DC voltage of the input end into an AC voltage, and then convert the AC voltage into a DC voltage and output it from the output end;

[0010] The first power supply terminal of the drive control module is electrically connected to the correction output terminal, the second power supply terminal of the drive control module is electrically connected to the output terminal of the first DC / DC module, and the output terminal of the drive control module is electrically connected to the control terminal of the second DC / DC module.

[0011] Optionally, the PFC module includes a first control chip, a second control chip, a first resistor, a second resistor, a first transistor, a voltage divider circuit, a first capacitor, a third resistor, a first diode, a second transistor, a first switch tube, a second diode, a second capacitor and a first voltage regulator tube; wherein the first control chip includes a first power supply terminal, a second power supply terminal and a drive output terminal, and the second control chip includes a PFC control signal input terminal and a PFC control signal output terminal;

[0012] The first end of the first resistor is electrically connected to the correction output end, the second end of the first resistor is electrically connected to the first end of the first transistor, the second end of the first transistor is electrically connected to the correction output end through the second resistor, and the third end of the first transistor is electrically connected to the first power supply end;

[0013] The first end of the voltage divider circuit is electrically connected to the correction output end, the second end of the voltage divider circuit is electrically connected to the second power supply end, the first end of the first capacitor is electrically connected to the second power supply end, and the second end of the first capacitor is electrically connected to the first ground end;

[0014] The driving output end is electrically connected to the PFC control signal input end, the PFC control signal output end is electrically connected to the first end of the second triode through the third resistor, the third end of the second triode is electrically connected to the third end of the first switch tube, the second end of the first switch tube is electrically connected to the anode of the second diode, the cathode of the second diode is electrically connected to the rectifier output end, the first end of the first switch tube is electrically connected to the PFC control signal output end through the first diode, and the first diode is connected in parallel between the first end and the second end of the second triode;

[0015] The first end of the second capacitor is electrically connected to the cathode of the second diode, the second end of the second capacitor is electrically connected to the second ground terminal, and the first voltage regulator is connected in parallel to the second capacitor.

[0016] Optionally, the PFC module further includes a third control chip and a third capacitor, wherein the third control chip includes a third power supply terminal and a power supply output terminal;

[0017] The first control chip further includes a fourth power supply terminal, the fourth power supply terminal is electrically connected to the power supply output terminal of the third control chip, and the third power supply terminal is electrically connected to the first voltage output terminal of the first DC / DC module;

[0018] A first end of the third capacitor is electrically connected to a power output end of the third control chip, and a second end of the third capacitor is electrically connected to a first ground end.

[0019] Optionally, the first DC / DC module includes a voltage conversion chip, a fourth resistor, a fifth resistor, a first transformer, a fourth capacitor, a third diode, a fourth diode, a third triode, a second voltage regulator, a fifth capacitor and a sixth resistor, wherein the voltage conversion chip includes an input voltage start-up terminal, a control terminal, a current input terminal and a voltage output terminal;

[0020] The first end of the fourth resistor is electrically connected to the rectifier output end, the second end of the fourth resistor is electrically connected to the input voltage start end through the fifth resistor, the voltage output end is electrically connected to the anode of the third diode, the cathode of the third diode is electrically connected to the first end of the primary winding of the first transformer through the fourth capacitor, and the second end of the primary winding is electrically connected to the current input end;

[0021] The first end of the first secondary winding of the first transformer is electrically connected to the second end of the third triode through the fourth diode, the third end of the third triode serves as the first voltage output end of the first DC / DC module to output voltage, the first end of the third triode is electrically connected to the positive electrode of the second voltage regulator tube, the negative electrode of the second voltage regulator tube is connected to the first end of the fifth capacitor and is grounded, the second end of the fifth capacitor is electrically connected to the third end of the third triode, and the second end of the first secondary winding of the first transformer is electrically connected to the first ground end;

[0022] The first end of the sixth resistor is electrically connected to the second end of the third transistor, and the second end of the sixth resistor is electrically connected to the control end;

[0023] The second control chip also includes a fourth power supply end, and the fourth power supply end is electrically connected to the third end of the third transistor through a seventh resistor.

[0024] Optionally, the first DC / DC module further includes a fifth diode, a sixth diode, a fourth transistor, a fifth transistor, a third voltage regulator, a fourth voltage regulator and a sixth capacitor;

[0025] The first end of the second secondary winding of the first transformer is electrically connected to the anode of the fifth diode, the cathode of the fifth diode is electrically connected to the second end of the fourth transistor, and the third end of the fourth transistor serves as the output end of the first DC / DC module to output the control voltage;

[0026] The first end of the fourth triode is electrically connected to the second end of the second secondary winding of the first transformer through the third voltage regulator, the first end of the sixth capacitor is electrically connected to the third end of the fourth triode, and the second end of the sixth capacitor is grounded;

[0027] The first end of the third secondary winding of the first transformer is electrically connected to the second end of the fifth transistor through the sixth diode, the third end of the fifth transistor serves as the second voltage output end of the first DC / DC module, and the first end of the fifth transistor is electrically connected to the second ground end through the fourth voltage regulator.

[0028] Optionally, the second DC / DC module includes a seventh capacitor, an eighth resistor, a seventh diode, an eighth diode, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a second switch tube, a third switch tube, a ninth diode and a tenth diode;

[0029] The first end of the seventh capacitor is electrically connected to the correction output end, the second end of the seventh capacitor is grounded, the second end of the second switch tube is electrically connected to the first end of the seventh capacitor, the third end of the second switch tube is electrically connected to the second end of the third switch tube, and the third end of the third switch tube is electrically connected to the second ground end;

[0030] The first end of the second switch tube is electrically connected to the first end of the eighth resistor through the seventh diode, the ninth resistor is connected in parallel with the seventh diode, the first end of the tenth resistor is electrically connected to the first end of the second switch tube, and the second end of the tenth resistor is electrically connected to the third end of the second switch tube;

[0031] The first end of the third switch tube is electrically connected to the first end of the eleventh resistor through the eighth diode, the twelfth resistor is connected in parallel with the eighth diode, the first end of the thirteenth resistor is electrically connected to the first end of the third switch tube, and the second end of the thirteenth resistor is electrically connected to the third end of the third switch tube;

[0032] The cathode of the ninth diode is electrically connected to the second end of the second switch tube, the anode of the ninth diode is electrically connected to the cathode of the tenth diode, and the anode of the tenth diode is electrically connected to the second ground terminal.

[0033] Optionally, the second DC / DC module further includes a second transformer, an eleventh diode, a twelfth diode, a fourteenth resistor, a fifteenth resistor, an eighth capacitor and a ninth capacitor;

[0034] The first end of the first winding of the second transformer is electrically connected to the third end of the second switching tube, the second end of the first winding of the second transformer is electrically connected to the cathode of the tenth diode, the first end of the second winding of the second transformer is electrically connected to the anode of the eleventh diode, the anode of the twelfth diode, the first end of the fourteenth resistor and the first end of the fifteenth resistor respectively, the second end of the fourteenth resistor and the second end of the fifteenth resistor are electrically connected to the first end of the eighth capacitor, the second end of the eighth capacitor is electrically connected to the cathode of the eleventh diode and the cathode of the twelfth diode, the first end of the ninth capacitor is electrically connected to the second end of the eighth capacitor, and the second end of the ninth capacitor is electrically connected to the second end of the second winding of the second transformer.

[0035] Optionally, the drive control module includes a fourth control chip, a sixth transistor, a sixteenth resistor, a tenth capacitor, a seventeenth resistor, an eighteenth resistor, an eleventh capacitor, a nineteenth resistor and a first optocoupler, wherein the fourth control chip includes a high voltage input terminal, a drive voltage input terminal, a current drive signal output terminal, a first voltage drive signal output terminal and a second voltage drive signal output terminal;

[0036] The first end of the seventeenth resistor is electrically connected to the correction output terminal, the second end of the seventeenth resistor is electrically connected to the high voltage input terminal through the eighteenth resistor, the first end of the eleventh capacitor is electrically connected to the high voltage input terminal, and the second end of the eleventh capacitor is electrically connected to the second ground terminal;

[0037] The first end of the first optical coupler is electrically connected to the output end of the first DC / DC module, the third end of the first optical coupler is grounded, the fourth end of the first optical coupler is electrically connected to the first end of the sixth triode through the nineteenth resistor, the second end of the sixth triode is electrically connected to the second voltage output end of the first DC / DC module, the third end of the sixth triode is electrically connected to the driving voltage input end through the sixteenth resistor, the first end of the tenth capacitor is electrically connected to the driving voltage input end, and the second end of the tenth capacitor is electrically connected to the second ground end;

[0038] The first voltage drive signal output terminal is electrically connected to the first end of the eighth resistor, the second voltage drive signal output terminal is electrically connected to the first end of the eleventh resistor, and the current drive signal output terminal is electrically connected to the third end of the second switch tube.

[0039] Optionally, the drive control module further includes a twentieth resistor, a twenty-first resistor, a twenty-second resistor, a twenty-third resistor, a twenty-fourth resistor, a twelfth capacitor, a thirteenth capacitor and a second optical coupler;

[0040] The first end of the 20th resistor is electrically connected to the output end of the first DC / DC module, the second end of the 20th resistor is electrically connected to the first end of the second optocoupler, the 21st resistor is connected in parallel between the first end and the second end of the second optocoupler, the 21st resistor is electrically connected to the third ground end through the 12th capacitor, the third end of the second optocoupler is electrically connected to the first ground end, and the fourth end of the second optocoupler is electrically connected to the voltage feedback end of the fourth control chip;

[0041] The first end of the 22nd resistor is electrically connected to the first end of the 9th capacitor, the second end of the 22nd resistor is electrically connected to the first end of the 24th resistor via the 23rd resistor and the 13th capacitor in sequence, and the second end of the 24th resistor is electrically connected to the second end of the second optocoupler.

[0042] Optionally, it also includes a PFC overvoltage protection circuit, a PFC overcurrent protection circuit and a PFC overtemperature protection circuit;

[0043] The input end of the PFC over-temperature protection circuit is electrically connected to the first voltage output end of the first DC / DC module, and the output end of the PFC over-temperature protection circuit is electrically connected to the induction voltage input end of the first control chip;

[0044] The input end of the PFC overcurrent protection circuit is electrically connected to the first voltage output end of the first DC / DC module, and the output end of the PFC overcurrent protection circuit is electrically connected to the induction voltage input end of the first control chip;

[0045] The input end of the PFC overvoltage protection circuit is electrically connected to the correction output end, and the output end of the PFC overvoltage protection circuit is electrically connected to the induced voltage input end of the first control chip;

[0046] It also includes an output voltage over-temperature protection circuit, an output voltage over-current protection circuit and an output voltage over-voltage protection circuit;

[0047] The input end of the output voltage over-temperature protection circuit is electrically connected to the first voltage output end of the first DC / DC module, and the output end of the output voltage over-temperature protection circuit is electrically connected to the input end of the drive control module;

[0048] The input end of the output voltage overcurrent protection circuit is electrically connected to the output end of the first DC / DC module, and the output end of the output voltage overcurrent protection circuit is electrically connected to the input end of the drive control module;

[0049] The input end of the output voltage overvoltage protection circuit is electrically connected to the output end of the second DC / DC module, and the output end of the output voltage overvoltage protection circuit is electrically connected to the input end of the drive control module.

[0050] The technical solution provided by the embodiment of the present invention realizes insulation isolation from the grid power supply through the rectifier filter module 10 and the PFC module 20, and realizes insulation isolation of the AC / DC power supply through the second DC / DC module 40, so as to realize insulation isolation from the human body. The first DC / DC module 30 is an isolated DC / DC conversion module, which converts the DC voltage output by the rectifier filter module 10 into the DC voltage required by the drive control module 50, and provides the power supply voltage for the drive control module 50. The first DC / DC module 30 is an auxiliary insulation to realize double insulation of the medical power supply circuit, prevent safety accidents when the equipment connected to the power supply contacts the human body, and improve the safety of the isolated power supply through double insulation of the power supply, thereby improving the insulation level of the power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 A schematic diagram of the structure of a medical power supply circuit provided by an embodiment of the present invention;

[0052] Figure 2 A schematic diagram of the structure of another medical power supply circuit provided by an embodiment of the present invention;

[0053] Figure 3 A schematic diagram of the structure of another medical power supply circuit provided by an embodiment of the present invention;

[0054] Figure 4 A schematic diagram of the structure of another medical power supply circuit provided by an embodiment of the present invention;

[0055] Figure 5 A schematic diagram of the structure of another medical power supply circuit provided by an embodiment of the present invention;

[0056] Figure 6 A schematic diagram of the structure of another medical power supply circuit provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0057] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0058] Figure 1 A schematic diagram of a medical power supply circuit provided by an embodiment of the present invention, referring to Figure 1 , the medical power supply circuit includes a rectifier filter module 10, a PFC module 20, a first DC / DC module 30, a second DC / DC module 40 and a drive control module 50;

[0059] The rectifier filter module 10 includes a rectifier input terminal A1 and a rectifier output terminal A2. The rectifier input terminal A1 is connected to an AC voltage. The rectifier filter module 10 is used to convert the AC voltage into a DC voltage.

[0060] The PFC module 20 includes a correction input terminal B1 and a correction output terminal B2, the correction input terminal B1 is electrically connected to the rectifier output terminal A2, and the PFC module 20 is used to reduce the output voltage of the correction output terminal B2 and correct the power factor of the output voltage;

[0061] The first DC / DC module 30 includes an input terminal C1 and an output terminal C2. The input terminal C1 of the first DC / DC module 30 is electrically connected to the rectifier output terminal A2. The first DC / DC module 30 converts the DC voltage output by the rectifier output terminal A2 and outputs it from the output terminal C2 of the first DC / DC module 30.

[0062] The second DC / DC module 40 includes an input terminal D1 and an output terminal D2. The input terminal D1 of the second DC / DC module 40 is electrically connected to the correction output terminal B2. The second DC / DC module 40 is used to convert the DC voltage of the input terminal D1 into an AC voltage, and then convert the AC voltage into a DC voltage and output it from the output terminal D2.

[0063] The first power supply terminal E1 of the drive control module 50 is electrically connected to the correction output terminal B2, the second power supply terminal E2 of the drive control module 50 is electrically connected to the output terminal C2 of the first DC / DC module 30, and the output terminal E3 of the drive control module 50 is electrically connected to the control terminal D3 of the second DC / DC module 40.

[0064] Specifically, the rectifier and filter module 10 rectifies and filters the AC voltage input from the rectifier input terminal A1, converts the AC voltage into a DC voltage to supply power to the PFC module 20 and the first DC / DC module. The PFC module 20 converts the DC voltage input from the correction input terminal B1 into the DC voltage required by the second DC / DC module 40, and corrects the power factor of the DC voltage and outputs it from the correction output terminal B2 to improve the voltage conversion efficiency of the second DC / DC module 40. The second DC / DC module 40 can be a DC / DC conversion module with an isolation function, which can achieve isolation of the output voltage from the input voltage from the input terminal D1, that is, isolation of the AC voltage from the output voltage. The drive control module 50 is used to output a PWM signal to drive the second DC / DC module 40. Exemplarily, the medical power supply circuit can be used as a medical power supply, and insulation isolation from the grid power supply is achieved through the rectifier and filter module 10 and the PFC module 20, and insulation isolation of the AC / DC power supply is achieved through the second DC / DC module 40 to achieve insulation isolation of the patient. The first DC / DC module 30 is a DC / DC conversion module with an isolation function, which converts the DC voltage output by the rectifier and filter module 10 into the DC voltage required by the drive control module 50, and provides the power supply voltage for the drive control module 50. The drive control module 50 outputs a PWM signal to drive the second DC / DC module 40. The second DC / DC module 40 receives the PWM signal and converts the voltage output by the PFC module 20 into an AC voltage, and then rectifies the AC voltage into a DC voltage for output. Basic insulation is achieved between the mains power supply and the medical power supply circuit, and auxiliary insulation is achieved between the medical power supply circuit and the human body through the PFC module 20, the first DC / DC module 30 and the second DC / DC module 40. Therefore, the medical power supply circuit can achieve double insulation to prevent safety accidents when the equipment connected to the power supply contacts the human body, and improve the safety of the isolated power supply through double insulation of the power supply.

[0065] Figure 2 A schematic diagram of another medical power supply circuit provided by an embodiment of the present invention, referring to Figure 2 On the basis of the above embodiment, the PFC module 20 includes a first control chip U1, a second control chip U2, a first resistor R1, a second resistor R2, a first transistor Q1, a voltage divider circuit 201, a first capacitor C1, a third resistor R3, a first diode D1, a second transistor Q2, a first switch tube Q3, a second diode D2, a second capacitor C2 and a first voltage regulator tube VD1; wherein the first control chip U1 includes a first power supply terminal 1, a second power supply terminal 2 and a drive output terminal 3, and the second control chip U2 includes a PFC control signal input terminal 11 and a PFC control signal output terminal 22;

[0066] The first end of the first resistor R1 is electrically connected to the correction output terminal B2, the second end of the first resistor R1 is electrically connected to the first end of the first transistor Q1, the second end of the first transistor Q1 is electrically connected to the correction output terminal B2 through the second resistor R2, and the third end of the first transistor Q1 is electrically connected to the first power supply terminal 1;

[0067] A first end of the voltage divider circuit 201 is electrically connected to the correction output terminal B2, a second end of the voltage divider circuit 201 is electrically connected to the second power supply terminal 2, a first end of the first capacitor C1 is electrically connected to the second power supply terminal 2, and a second end of the first capacitor C1 is electrically connected to the first ground terminal;

[0068] The driving output terminal 3 is electrically connected to the PFC control signal input terminal 11, the PFC control signal output terminal 22 is electrically connected to the first end of the second triode Q2 through the third resistor R3, the third end of the second triode Q2 is electrically connected to the third end of the first switch tube Q3, the second end of the first switch tube Q3 is electrically connected to the anode of the second diode D2, the cathode of the second diode D2 is electrically connected to the rectifier output terminal A2, the first end of the first switch tube Q3 is electrically connected to the PFC control signal output terminal 22 through the first diode D1, and the first diode D1 is connected in parallel between the first end and the second end of the second triode Q2;

[0069] A first end of the second capacitor C2 is electrically connected to the cathode of the second diode D2, a second end of the second capacitor C2 is electrically connected to the second ground terminal, and the first voltage regulator tube VD1 is connected in parallel to the second capacitor C2.

[0070] Specifically, the first control chip U1, the first resistor R1, the second resistor R2, the first transistor Q1, the voltage divider circuit 201 and the first capacitor C1 together constitute a PFC control circuit 220, and the third resistor R3, the first diode D1, the second transistor Q2, the first switch tube Q3, the second diode D2, the second capacitor C2 and the first voltage regulator tube VD1 together constitute a PFC step-down circuit 210, which is used to step down the DC voltage output by the rectifier and filter module 10. Exemplarily, the second control chip U2 can be a UCC27511DBVR driver chip, the PFC control signal input terminal 11 receives the drive control signal output by the drive output terminal 3, and converts it into a PWM signal and outputs it from the PFC control signal output terminal 22, and the third resistor R3 is a current limiting resistor at the first end of the second transistor Q2 to prevent the drive current from being too large and damaging the second transistor Q2. Since the driving capability of the PWM signal output by the second control chip U2 is insufficient to drive the first switch tube Q3 to work, the current output by the second control chip U2 is amplified by the second transistor Q2 to improve the driving capability of the PWM signal output by the second control chip U2 to drive the first switch tube Q3. The first switch tube Q3, the second capacitor C2, the second diode D2 and the first inductor L1 together constitute a step-down chopper circuit, which converts the DC voltage output by the rectifier and filter module 10 into a low-voltage DC voltage V bus Output from the correction output terminal B2. The first voltage regulator VD1 is used to clamp the DC voltage output by the step-down chopper circuit to keep the output DC voltage constant. Among them, the grounding network of the first inductor L1 is the first grounding terminal GND1, and the grounding network of the first voltage regulator VD1 is the second grounding terminal GND2, that is, the DC voltage output by the rectifier and filter module 10 does not share the same grounding network with the PFC step-down circuit 210, thereby achieving insulation between the AC input voltage and the DC voltage output by the PFC module 20.

[0071] The low voltage DC voltage V can be corrected by the first control chip U1. bus Specifically, the first resistor R1 and the second resistor R2 are current limiting resistors, and the first power supply terminal 1 inputs a low voltage DC voltage V through the first transistor Q1. bus The second power supply terminal 2 inputs a low voltage DC voltage V through a voltage divider circuit 201. bus For example, the first control chip U1 may be a UCC29910APWR buck PFC chip, which can realize buck power factor correction in a wide input voltage range, and improve the low voltage DC voltage V bus The power factor of the voltage divider circuit 201 can be composed of multiple resistors.

[0072] Optional, continue to refer to Figure 2, based on the above embodiment, the PFC module 20 further includes a third control chip U3 and a third capacitor C3, wherein the third control chip U3 includes a third power supply terminal 111 and a power supply output terminal 222;

[0073] The first control chip U1 further includes a fourth power supply terminal 4, the fourth power supply terminal 1 is electrically connected to the power supply output terminal 222 of the third control chip U3, and the third power supply terminal 111 is electrically connected to the first voltage output terminal C31 of the first DC / DC module 30;

[0074] A first end of the third capacitor C3 is electrically connected to the power output terminal 222 of the third control chip U3 , and a second end of the third capacitor C3 is electrically connected to the first ground terminal.

[0075] Specifically, the third control chip U3 is a DC voltage conversion chip, which can convert a larger DC voltage into a smaller DC voltage to provide a driving voltage for the first control chip U1. The third control chip U3 and the third capacitor C3 constitute a PFC power supply circuit 230, and the PFC power supply circuit 230 provides a driving voltage for the PFC control circuit 220, and the PFC power supply circuit 230 and the PFC control circuit 220 share the same grounding network.

[0076] Optional, Figure 3 A schematic diagram of another medical power supply circuit provided by an embodiment of the present invention, referring to Figure 2 and Figure 3 On the basis of the above embodiment, the first DC / DC module 30 includes a voltage conversion chip U4, a fourth resistor R4, a fifth resistor R5, a first transformer T1, a fourth capacitor C4, a third diode D3, a fourth diode D4, a third transistor Q4, a second voltage regulator tube VD2, a fifth capacitor C5 and a sixth resistor R6, wherein the voltage conversion chip U4 includes an input voltage start terminal 41, a control terminal 44, a current input terminal 43 and a voltage output terminal 42;

[0077] A first end of a fourth resistor R4 is electrically connected to the rectifier output terminal A2, a second end of the fourth resistor R4 is electrically connected to the input voltage start terminal 41 through a fifth resistor R5, a voltage output terminal 42 is electrically connected to an anode of a third diode D3, a cathode of the third diode D3 is electrically connected to a first end of a primary winding T1-A of a first transformer T1 through a fourth capacitor C4, and a second end of the primary winding T1-A is electrically connected to a current input terminal 43;

[0078] The first end of the first secondary winding T1-B of the first transformer T1 is electrically connected to the second end of the third triode Q4 through the fourth diode D4, the third end of the third triode Q4 outputs voltage as the first voltage output terminal C31 of the first DC / DC module 30, the first end of the third triode Q4 is electrically connected to the positive electrode of the second voltage regulator tube VD2, the negative electrode of the second voltage regulator tube VD2 is connected to the first end of the fifth capacitor C5 and is grounded, the second end of the fifth capacitor C5 is electrically connected to the third end of the third triode Q4, and the second end of the first secondary winding T1-B of the first transformer T1 is electrically connected to the first grounding terminal;

[0079] A first end of the sixth resistor R6 is electrically connected to the second end of the third transistor Q4, and a second end of the sixth resistor R6 is electrically connected to the control end 44;

[0080] The second control chip U2 further includes a fourth power supply terminal 33 , and the fourth power supply terminal 33 is electrically connected to the third terminal of the third transistor Q4 through the seventh resistor R7 .

[0081] Specifically, the voltage conversion chip U4 is a DC / DC voltage conversion chip with a wide voltage input. For example, the voltage conversion chip U4 may be TNY290KG, which can realize direct current voltage conversion. The DC voltage output by the rectifier and filter module 10 is divided by the fourth resistor R4 and the fifth resistor R5 to provide an input voltage for the voltage conversion chip U4. The voltage conversion chip U4 converts the input voltage into a voltage corresponding to the primary winding T1-A. The first end of the first secondary winding T1-B is electrically connected to the collector of the third transistor Q4 through the fourth diode D4, and the collector of the third transistor Q4 is electrically connected to the control end 44 of the voltage conversion chip U4 through the sixth resistor R6. Therefore, the voltage conversion chip U4 is connected to the first secondary winding T1-B with a common collector to amplify the output current, and then outputs a DC voltage VPFC10 through the third transistor Q4. VPFC10 is used as the DC voltage output by the first voltage output end C31 of the first DC / DC module 30 and is electrically connected to the third power supply end 111 of the third control chip U3 to provide a power supply voltage for the third control chip U3.

[0082] Optionally, based on the above embodiment, continue to refer to Figure 3 , the first DC / DC module 30 further includes a fifth diode D5, a sixth diode D6, a fourth transistor Q5, a fifth transistor Q6, a third voltage regulator tube VD3, a fourth voltage regulator tube VD4 and a sixth capacitor C6;

[0083] A first end of the second secondary winding T1-C of the first transformer T1 is electrically connected to an anode of a fifth diode D5, a cathode of the fifth diode D5 is electrically connected to a second end of a fourth transistor Q5, and a third end of the fourth transistor Q5 serves as an output end C2 of the first DC / DC module 30 to output a control voltage;

[0084] A first end of the fourth transistor Q5 is electrically connected to a second end of the second secondary winding T1-C of the first transformer T1 through a third voltage regulator VD3, a first end of the sixth capacitor C6 is electrically connected to a third end of the fourth transistor Q5, and a second end of the sixth capacitor C6 is grounded;

[0085] The first end of the third secondary winding T1-D of the first transformer T1 is electrically connected to the second end of the fifth transistor Q6 through the sixth diode D6, the third end of the fifth transistor Q6 serves as the second voltage output end of the first DC / DC module 30, and the first end of the fifth transistor Q6 is electrically connected to the second ground end through the fourth voltage regulator tube VD4.

[0086] Specifically, the second secondary winding T1-C and the third secondary winding T1-D respectively sense the voltage on the main winding T1-A side to output an AC voltage. The fifth diode D5, the fourth transistor Q5, the third voltage regulator VD3 and the sixth capacitor C6 together form an inverter circuit to convert the AC voltage output by the second secondary winding T1-C into a DC voltage VS12. The sixth diode D6, the fifth transistor Q6 and the third voltage regulator VD3 form an inverter circuit to convert the AC voltage output by the third secondary winding T1-D into a DC voltage VP12. Both the DC voltages VS12 and VP12 are insulated and isolated by the first transformer T1, and the DC voltage VP12 is isolated from the low-voltage DC voltage V bus Share a common ground network.

[0087] Optional, Figure 4 A schematic diagram of another medical power supply circuit provided by an embodiment of the present invention, referring to Figure 3 and Figure 4 On the basis of the above embodiment, the second DC / DC module 40 includes a seventh capacitor C7, an eighth resistor R8, a seventh diode D7, an eighth diode D8, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a second switch tube Q7, a third switch tube Q8, a ninth diode D9 and a tenth diode D10;

[0088] A first end of the seventh capacitor C7 is electrically connected to the correction output end B2, a second end of the seventh capacitor C7 is grounded, a second end of the second switch tube Q7 is electrically connected to the first end of the seventh capacitor C7, a third end of the second switch tube Q7 is electrically connected to the second end of the third switch tube Q8, and a third end of the third switch tube Q8 is electrically connected to the second ground end;

[0089] A first end of the second switch tube Q7 is electrically connected to a first end of the eighth resistor R8 through a seventh diode D7, a ninth resistor R9 is connected in parallel to the seventh diode D7, a first end of the tenth resistor R10 is electrically connected to a first end of the second switch tube Q7, and a second end of the tenth resistor R10 is electrically connected to a third end of the second switch tube Q7;

[0090] A first end of the third switch tube Q8 is electrically connected to a first end of the eleventh resistor R11 through an eighth diode D8, a twelfth resistor R12 is connected in parallel to the eighth diode D8, a first end of the thirteenth resistor R13 is electrically connected to a first end of the third switch tube Q8, and a second end of the thirteenth resistor R13 is electrically connected to a third end of the third switch tube Q8;

[0091] The cathode of the ninth diode D9 is electrically connected to the second end of the second switch tube Q7 , the anode of the ninth diode is electrically connected to the cathode of the tenth diode D10 , and the anode of the tenth diode D10 is electrically connected to the second ground end.

[0092] The second DC / DC module 40 is used to output a DC voltage for use in medical devices such as ultrasonic scalpels. First, the second DC / DC module 40 converts the low voltage DC voltage V output by the PFC module 20 into a DC voltage. bus The push-pull circuit converts the AC voltage into AC voltage, and then steps down the voltage through the second transformer T2, and finally rectifies the output DC voltage. Exemplarily, the second switch tube Q7 and the third switch tube Q8 form a push-pull circuit, and the drive control module 50 outputs a set of complementary drive signals to drive the switches of the second switch tube Q7 and the third switch tube Q8 respectively, so that when the second switch tube Q7 is turned on, the third switch tube Q8 is turned off; or when the second switch tube Q7 is turned off, the third switch tube Q8 is turned on. The second switch tube Q7 and the third switch tube Q8 are turned on alternately to output AC voltage.

[0093] Optional, continue to refer to Figure 4 , the second DC / DC module 40 further includes a second transformer T2, an eleventh diode D11, a twelfth diode D12, a fourteenth resistor R14, a fifteenth resistor R15, an eighth capacitor C8 and a ninth capacitor C9;

[0094] A first end of the first winding T2-A of the second transformer T2 is electrically connected to the third end of the second switch tube Q7, a second end of the first winding T2-A of the second transformer T2 is electrically connected to the cathode of the tenth diode D10, a first end of the second winding T2-B of the second transformer T2 is electrically connected to the anode of the eleventh diode D11, the anode of the twelfth diode D12, the first end of the fourteenth resistor R14 and the first end of the fifteenth resistor R15 respectively, a second end of the fourteenth resistor R14 and the second end of the fifteenth resistor R15 are electrically connected to the first end of the eighth capacitor C8, a second end of the eighth capacitor C8 is electrically connected to the cathode of the eleventh diode D11 and the cathode of the twelfth diode D12, a first end of the ninth capacitor C9 is electrically connected to the second end of the eighth capacitor C8, and a second end of the ninth capacitor C9 is electrically connected to the second end of the second winding T2-B of the second transformer T2.

[0095] Specifically, the second transformer T2 is a step-down transformer, the second winding T2-B senses the AC voltage on the first winding T2-A side and steps it down, the eleventh diode D11 and the twelfth diode D12 form a half-bridge rectifier circuit, and rectify the AC voltage output by the second winding T2-B into a DC voltage, and the ninth capacitor C9 is a filter capacitor, which filters out the noise of the output voltage after rectification by the eleventh diode D11 and the twelfth diode D12.

[0096] Optional, Figure 5 A schematic diagram of another medical power supply circuit provided by an embodiment of the present invention, referring to Figure 4 and Figure 5 On the basis of the above embodiment, the driving control module 50 includes a fourth control chip U5, a sixth transistor Q9, a sixteenth resistor R16, a tenth capacitor C10, a seventeenth resistor R17, an eighteenth resistor R18, an eleventh capacitor C11, a nineteenth resistor R19 and a first optical coupler OC1, wherein the fourth control chip U5 includes a high voltage input terminal 52, a driving voltage input terminal 54, a current driving signal output terminal 53, a first voltage driving signal output terminal 51 and a second voltage driving signal output terminal 55;

[0097] A first end of a seventeenth resistor R17 is electrically connected to the correction output terminal B2, a second end of the seventeenth resistor R17 is electrically connected to the high voltage input terminal 52 via an eighteenth resistor R18, a first end of an eleventh capacitor C11 is electrically connected to the high voltage input terminal 52, and a second end of the eleventh capacitor C11 is electrically connected to the second ground terminal;

[0098] A first end of the first optical coupler OC1 is electrically connected to the output terminal C2 of the first DC / DC module 30, a third end of the first optical coupler OC1 is electrically connected to the first ground terminal, a fourth end of the first optical coupler OC1 is electrically connected to the first end of the sixth transistor 9 through a nineteenth resistor R19, a second end of the sixth transistor Q9 is electrically connected to the second voltage output terminal of the first DC / DC module 30, a third end of the sixth transistor Q9 is electrically connected to the driving voltage input terminal 54 through a sixteenth resistor R16, a first end of the tenth capacitor C10 is electrically connected to the driving voltage input terminal 54, and a second end of the tenth capacitor C10 is electrically connected to the second ground terminal;

[0099] The first voltage drive signal output terminal 51 is electrically connected to the first end of the eighth resistor R8, the second voltage drive signal output terminal 55 is electrically connected to the first end of the eleventh resistor R11, and the current drive signal output terminal 56 is electrically connected to the third end of the second switch tube Q7.

[0100] Specifically, the fourth control chip U5 can be a PWM driver chip of the L6599ADTR model, which is used to generate a PWM signal with a 50% complementary duty cycle to drive the second switch tube Q7 and the third switch tube Q8 to turn on, and when the second switch tube Q7 is turned off, the third switch tube Q8 can achieve soft switching, or when the third switch tube Q8 is turned off, the second switch tube Q7 can achieve soft switching to reduce the loss of the second DC / DC module 40. The first optical coupler OC1 is used to convert the DC voltage VS12 output by the output terminal C2 of the first DC / DC module 30 into the driving voltage of the sixth transistor Q9 to drive the sixth transistor Q9 to turn on normally, and the first optical coupler OC1 can achieve electrical isolation to ensure the insulation inside the drive control module 50. The sixth transistor Q9 is used to amplify the driving current of the fourth control chip U5 to ensure that the fourth control chip U5 can work normally. The seventeenth resistor R17 and the eighteenth resistor R18 are voltage divider resistors to ensure that the voltage input at the high-voltage input terminal 52 matches the safe working voltage of the fourth control chip U5.

[0101] Optional, continue to refer to Figure 5 On the basis of the above embodiment, the driving control module 50 further includes a twentieth resistor R20, a twenty-first resistor R21, a twenty-second resistor R22, a twenty-third resistor R23, a twenty-fourth resistor R24, a twelfth capacitor C12, a thirteenth capacitor C13 and a second optical coupler OC2;

[0102] A first end of the twentieth resistor R20 is electrically connected to the output terminal C2 of the first DC / DC module 30, a second end of the twentieth resistor R20 is electrically connected to the first end of the second optical coupler OC2, a twenty-first resistor R21 is connected in parallel between the first end and the second end of the second optical coupler OC2, the twenty-first resistor R21 is electrically connected to the third ground terminal through the twelfth capacitor C12, a third end of the second optical coupler OC2 is electrically connected to the first ground terminal, and a fourth end of the second optical coupler OC2 is electrically connected to the voltage feedback terminal 53 of the fourth control chip U5;

[0103] The first end of the twenty-second resistor R22 is electrically connected to the first end of the ninth capacitor C9, the second end of the twenty-second resistor R22 is electrically connected to the first end of the twenty-fourth resistor R24 ​​via the twenty-third resistor R23 and the thirteenth capacitor C13 in sequence, and the second end of the twenty-fourth resistor R24 ​​is electrically connected to the second end of the second optocoupler OC2.

[0104] Specifically, the DC voltage VS12 outputted from the output terminal C2 of the first DC / DC module 30 is collected by the second optical coupler OC2 via the twentieth resistor R20 and the twenty-first resistor R21, and the DC voltage US outputted from the second DC / DC module 40 is collected by the second optical coupler OC2 via the twenty-second resistor R22 and the twenty-third resistor R23, and the second optical coupler OC2 outputs the collected DC voltage US to the voltage feedback terminal 53 of the fourth control chip U5, and the fourth control chip U5 adjusts the output PWM signal according to the collected DC voltage US, and changes the duty cycle, so as to achieve the stable output of the DC voltage US outputted by the second DC / DC module 40. Since the optical coupler has the characteristics of mutual isolation between input and output, and unidirectional transmission of electrical signals, it has good electrical insulation and anti-interference capabilities, and can achieve insulation between the second DC / DC module 40 and the drive control module 50.

[0105] Optional, Figure 6 A schematic diagram of another medical power supply circuit provided by an embodiment of the present invention, referring to Figure 6 , based on the above embodiment, the medical power supply circuit further includes a PFC overvoltage protection circuit 80, a PFC overcurrent protection circuit 70 and a PFC overtemperature protection circuit 60;

[0106] The input end of the PFC over-temperature protection circuit 60 is electrically connected to the first voltage output end C31 of the first DC / DC module 30, and the output end of the PFC over-temperature protection circuit 60 is electrically connected to the induction voltage input end 5 of the first control chip U1;

[0107] The input end of the PFC overcurrent protection circuit 70 is electrically connected to the first voltage output end C31 of the first DC / DC module 30, and the output end of the PFC overcurrent protection circuit 70 is electrically connected to the induction voltage input end 5 of the first control chip U1;

[0108] The input end of the PFC overvoltage protection circuit 80 is electrically connected to the correction output end B2, and the output end of the PFC overvoltage protection circuit 80 is electrically connected to the induction voltage input end 5 of the first control chip U1;

[0109] It also includes an output voltage over-temperature protection circuit 90, an output voltage over-current protection circuit 100 and an output voltage over-voltage protection circuit 110;

[0110] The input end of the output voltage over-temperature protection circuit 90 is electrically connected to the first voltage output end C31 of the first DC / DC module 30, and the output end of the output voltage over-temperature protection circuit 90 is electrically connected to the input end E4 of the drive control module 50;

[0111] The input end of the output voltage overcurrent protection circuit 100 is electrically connected to the output end C2 of the first DC / DC module 30, and the output end of the output voltage overcurrent protection circuit 100 is electrically connected to the input end E4 of the drive control module 50;

[0112] An input end of the output voltage overvoltage protection circuit 110 is electrically connected to an output end of the second DC / DC module 40 , and an output end of the output voltage overvoltage protection circuit 110 is electrically connected to an input end of the drive control module 50 .

[0113] Specifically, the DC voltage VPFC10 outputted by the first voltage output terminal C31 of the first DC / DC module 30 provides a power supply voltage for the PFC overcurrent protection circuit 70 and the PFC overtemperature protection circuit 60. The output terminals of the PFC overcurrent protection circuit 70 and the PFC overtemperature protection circuit 60 are both electrically connected to the inductive voltage input terminal 5 of the first control chip U1 to adjust the output signal of the first control chip U1 to protect the PFC buck circuit 210. The PFC overvoltage protection circuit 80 receives the low voltage DC voltage V outputted by the correction output terminal B2. bus , according to V bus The size of the first control chip U1 is used to control the output signal to ensure that V bus The output voltage overvoltage protection circuit 110 receives the output voltage US of the second DC / DC module 40 and feeds it back to the input terminal E4 of the drive control module 50. When the voltage US is overvoltage, the duty cycle of the PWM signal is changed through the fourth control chip U5 to adjust the output voltage US, and the low voltage DC voltage V is realized through the first optical coupler OC1. bus Isolation from PWM control signal.

[0114] Continue to refer Figure 6The medical power supply circuit includes a rectifier filter module 10, a PFC module 20, a first DC / DC module 30, a second DC / DC module 40, a drive control module 50, a PFC overvoltage protection circuit 80, a PFC overcurrent protection circuit 70, a PFC overtemperature protection circuit 60, an output voltage overtemperature protection circuit 90, an output voltage overcurrent protection circuit 100 and an output voltage overvoltage protection circuit 110. The specific working principle is as follows:

[0115] The rectifier and filter module 10 suppresses common-mode interference through the common-mode inductors L2, L3, and L4, and then rectifies the AC voltage output by the mains power supply through the rectifier bridge BR. On the basis of converting the AC voltage into a DC voltage, the electromagnetic compatibility problem of the medical power supply circuit can be reduced. The PFC module 20 steps down the output voltage after rectification by the rectifier and filter module 10, and increases the output low-voltage DC voltage V of the PFC module 20. bus The power factor is reduced to improve the voltage conversion efficiency of the second DC / DC module 40. The DC voltage output by the rectifier and filter module 10 and the PFC step-down circuit 210 do not share the same grounding network, thus achieving insulation between the AC input voltage and the DC voltage output by the PFC module 20. The second DC / DC module 40 is a push-pull DC / DC voltage conversion module. The second DC / DC module 40 first converts the low voltage DC voltage V bus The push-pull circuit converts the AC voltage into an AC voltage, which is then stepped down by the second transformer T2. Finally, the output AC voltage after the step-down by the second transformer T2 is converted into a DC voltage output by a half-bridge rectifier circuit, and the output voltage overvoltage protection circuit 110 protects the medical power supply circuit from overvoltage.

[0116] The first DC / DC module 30 converts the low voltage DC voltage V output by the PFC module 20 into bus The first DC / DC module 30 converts the control voltage into a control voltage corresponding to the drive control module 50, and realizes electrical isolation between the control voltage and the output voltage of the medical power supply circuit through the first transformer, thereby improving the insulation capacity of the circuit.

[0117] The technical solution provided by the embodiment of the present invention realizes insulation isolation from the grid power supply through the rectifier filter module 10 and the PFC module 20, and realizes insulation isolation of the AC / DC power supply through the second DC / DC module 40, so as to realize insulation isolation from the human body. The first DC / DC module 30 is an isolated DC / DC conversion module, which converts the DC voltage output by the rectifier filter module 10 into the DC voltage required by the drive control module 50, and provides the power supply voltage for the drive control module 50. The drive control module 50 outputs a PWM signal to drive the second DC / DC module 40, and the second DC / DC module 40 receives the PWM signal to convert the voltage output by the PFC module 20 into an AC voltage first, and then rectifies the AC voltage into a DC voltage output. Basic insulation is achieved between the grid power supply and the medical power supply circuit, and auxiliary insulation is achieved between the medical power supply circuit and the human body through the PFC module 20, the first DC / DC module 30 and the second DC / DC module 40, so that the medical power supply circuit can achieve double insulation, prevent the equipment connected to the power supply, such as medical equipment such as ultrasonic scalpels, from causing safety accidents when contacting the human body, and improve the safety of the isolated power supply through double insulation of the power supply.

[0118] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A medical power supply circuit, characterized in that: include: Rectification and filtering module, PFC module, first DC / DC module, second DC / DC module and drive control module; The rectification and filtering module comprises a rectification input terminal and a rectification output terminal, the rectification input terminal is connected to an AC voltage, and the rectification and filtering module is used to convert the AC voltage into a DC voltage; The PFC module comprises a correction input terminal and a correction output terminal, the correction input terminal is electrically connected to the rectifier output terminal, and the PFC module is used to reduce the output voltage of the correction output terminal and correct the power factor of the output voltage; The first DC / DC module includes an input end and an output end, the input end of the first DC / DC module is electrically connected to the rectifier output end, and the first DC / DC module converts a DC voltage output by the rectifier output end and outputs the DC voltage from the output end of the first DC / DC module; The second DC / DC module comprises an input end and an output end, the input end of the second DC / DC module is electrically connected to the correction output end, and the second DC / DC module is used to convert the DC voltage of the input end into an AC voltage, and then convert the AC voltage into a DC voltage and output it from the output end; The first power supply terminal of the drive control module is electrically connected to the correction output terminal, the second power supply terminal of the drive control module is electrically connected to the output terminal of the first DC / DC module, and the output terminal of the drive control module is electrically connected to the control terminal of the second DC / DC module.

2. The medical power supply circuit according to claim 1, characterized in that: The PFC module includes a first control chip, a second control chip, a first resistor, a second resistor, a first transistor, a voltage divider circuit, a first capacitor, a third resistor, a first diode, a second transistor, a first switch tube, a second diode, a second capacitor and a first voltage regulator tube; wherein the first control chip includes a first power supply terminal, a second power supply terminal and a drive output terminal, and the second control chip includes a PFC control signal input terminal and a PFC control signal output terminal; The first end of the first resistor is electrically connected to the correction output end, the second end of the first resistor is electrically connected to the first end of the first transistor, the second end of the first transistor is electrically connected to the correction output end through the second resistor, and the third end of the first transistor is electrically connected to the first power supply end; The first end of the voltage divider circuit is electrically connected to the correction output end, the second end of the voltage divider circuit is electrically connected to the second power supply end, the first end of the first capacitor is electrically connected to the second power supply end, and the second end of the first capacitor is electrically connected to the first ground end; The driving output end is electrically connected to the PFC control signal input end, the PFC control signal output end is electrically connected to the first end of the second triode through the third resistor, the third end of the second triode is electrically connected to the third end of the first switch tube, the second end of the first switch tube is electrically connected to the anode of the second diode, the cathode of the second diode is electrically connected to the rectifier output end, the first end of the first switch tube is electrically connected to the PFC control signal output end through the first diode, and the first diode is connected in parallel between the first end and the second end of the second triode; The first end of the second capacitor is electrically connected to the cathode of the second diode, the second end of the second capacitor is electrically connected to the second ground terminal, and the first voltage regulator is connected in parallel to the second capacitor.

3. The medical power supply circuit according to claim 2, characterized in that: The PFC module further includes a third control chip and a third capacitor, wherein the third control chip includes a third power supply terminal and a power supply output terminal; The first control chip further includes a fourth power supply terminal, the fourth power supply terminal is electrically connected to the power supply output terminal of the third control chip, and the third power supply terminal is electrically connected to the first voltage output terminal of the first DC / DC module; A first end of the third capacitor is electrically connected to a power output end of the third control chip, and a second end of the third capacitor is electrically connected to a first ground end.

4. The medical power supply circuit according to claim 3, characterized in that: The first DC / DC module includes a voltage conversion chip, a fourth resistor, a fifth resistor, a first transformer, a fourth capacitor, a third diode, a fourth diode, a third triode, a second voltage regulator, a fifth capacitor and a sixth resistor, wherein the voltage conversion chip includes an input voltage start-up terminal, a control terminal, a current input terminal and a voltage output terminal; The first end of the fourth resistor is electrically connected to the rectifier output end, the second end of the fourth resistor is electrically connected to the input voltage start end through the fifth resistor, the voltage output end is electrically connected to the anode of the third diode, the cathode of the third diode is electrically connected to the first end of the primary winding of the first transformer through the fourth capacitor, and the second end of the primary winding is electrically connected to the current input end; The first end of the first secondary winding of the first transformer is electrically connected to the second end of the third triode through the fourth diode, the third end of the third triode serves as the first voltage output end of the first DC / DC module to output voltage, the first end of the third triode is electrically connected to the positive electrode of the second voltage regulator tube, the negative electrode of the second voltage regulator tube is connected to the first end of the fifth capacitor and is grounded, the second end of the fifth capacitor is electrically connected to the third end of the third triode, and the second end of the first secondary winding of the first transformer is electrically connected to the first ground end; The first end of the sixth resistor is electrically connected to the second end of the third transistor, and the second end of the sixth resistor is electrically connected to the control end; The second control chip also includes a fourth power supply end, and the fourth power supply end is electrically connected to the third end of the third transistor through a seventh resistor.

5. The medical power supply circuit according to claim 4, characterized in that: The first DC / DC module further includes a fifth diode, a sixth diode, a fourth transistor, a fifth transistor, a third voltage regulator, a fourth voltage regulator and a sixth capacitor; The first end of the second secondary winding of the first transformer is electrically connected to the anode of the fifth diode, the cathode of the fifth diode is electrically connected to the second end of the fourth transistor, and the third end of the fourth transistor serves as the output end of the first DC / DC module to output the control voltage; The first end of the fourth triode is electrically connected to the second end of the second secondary winding of the first transformer through the third voltage regulator, the first end of the sixth capacitor is electrically connected to the third end of the fourth triode, and the second end of the sixth capacitor is grounded; The first end of the third secondary winding of the first transformer is electrically connected to the second end of the fifth transistor through the sixth diode, the third end of the fifth transistor serves as the second voltage output end of the first DC / DC module, and the first end of the fifth transistor is electrically connected to the second ground end through the fourth voltage regulator.

6. The medical power supply circuit according to claim 5, characterized in that: The second DC / DC module includes a seventh capacitor, an eighth resistor, a seventh diode, an eighth diode, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a second switch tube, a third switch tube, a ninth diode and a tenth diode; The first end of the seventh capacitor is electrically connected to the correction output end, the second end of the seventh capacitor is grounded, the second end of the second switch tube is electrically connected to the first end of the seventh capacitor, the third end of the second switch tube is electrically connected to the second end of the third switch tube, and the third end of the third switch tube is electrically connected to the second ground end; The first end of the second switch tube is electrically connected to the first end of the eighth resistor through the seventh diode, the ninth resistor is connected in parallel with the seventh diode, the first end of the tenth resistor is electrically connected to the first end of the second switch tube, and the second end of the tenth resistor is electrically connected to the third end of the second switch tube; The first end of the third switch tube is electrically connected to the first end of the eleventh resistor through the eighth diode, the twelfth resistor is connected in parallel with the eighth diode, the first end of the thirteenth resistor is electrically connected to the first end of the third switch tube, and the second end of the thirteenth resistor is electrically connected to the third end of the third switch tube; The cathode of the ninth diode is electrically connected to the second end of the second switch tube, the anode of the ninth diode is electrically connected to the cathode of the tenth diode, and the anode of the tenth diode is electrically connected to the second ground terminal.

7. The medical power supply circuit according to claim 6, characterized in that: The second DC / DC module further includes a second transformer, an eleventh diode, a twelfth diode, a fourteenth resistor, a fifteenth resistor, an eighth capacitor and a ninth capacitor; The first end of the first winding of the second transformer is electrically connected to the third end of the second switching tube, the second end of the first winding of the second transformer is electrically connected to the cathode of the tenth diode, the first end of the second winding of the second transformer is electrically connected to the anode of the eleventh diode, the anode of the twelfth diode, the first end of the fourteenth resistor and the first end of the fifteenth resistor respectively, the second end of the fourteenth resistor and the second end of the fifteenth resistor are electrically connected to the first end of the eighth capacitor, the second end of the eighth capacitor is electrically connected to the cathode of the eleventh diode and the cathode of the twelfth diode, the first end of the ninth capacitor is electrically connected to the second end of the eighth capacitor, and the second end of the ninth capacitor is electrically connected to the second end of the second winding of the second transformer.

8. The medical power supply circuit according to claim 7, characterized in that: The drive control module includes a fourth control chip, a sixth triode, a sixteenth resistor, a tenth capacitor, a seventeenth resistor, an eighteenth resistor, an eleventh capacitor, a nineteenth resistor and a first optical coupler, wherein the fourth control chip includes a high voltage input terminal, a drive voltage input terminal, a current drive signal output terminal, a first voltage drive signal output terminal and a second voltage drive signal output terminal; The first end of the seventeenth resistor is electrically connected to the correction output terminal, the second end of the seventeenth resistor is electrically connected to the high voltage input terminal through the eighteenth resistor, the first end of the eleventh capacitor is electrically connected to the high voltage input terminal, and the second end of the eleventh capacitor is electrically connected to the second ground terminal; The first end of the first optical coupler is electrically connected to the output end of the first DC / DC module, the third end of the first optical coupler is electrically connected to the first ground end, the fourth end of the first optical coupler is electrically connected to the first end of the sixth transistor through the nineteenth resistor, the second end of the sixth transistor is electrically connected to the second voltage output end of the first DC / DC module, the third end of the sixth transistor is electrically connected to the driving voltage input end through the sixteenth resistor, the first end of the tenth capacitor is electrically connected to the driving voltage input end, and the second end of the tenth capacitor is electrically connected to the second ground end; The first voltage drive signal output terminal is electrically connected to the first end of the eighth resistor, the second voltage drive signal output terminal is electrically connected to the first end of the eleventh resistor, and the current drive signal output terminal is electrically connected to the third end of the second switch tube.

9. The medical power supply circuit according to claim 8, characterized in that: The drive control module further includes a twentieth resistor, a twenty-first resistor, a twenty-second resistor, a twenty-third resistor, a twenty-fourth resistor, a twelfth capacitor, a thirteenth capacitor and a second optical coupler; The first end of the 20th resistor is electrically connected to the output end of the first DC / DC module, the second end of the 20th resistor is electrically connected to the first end of the second optocoupler, the 21st resistor is connected in parallel between the first end and the second end of the second optocoupler, the 21st resistor is electrically connected to the third ground end through the 12th capacitor, the third end of the second optocoupler is electrically connected to the first ground end, and the fourth end of the second optocoupler is electrically connected to the voltage feedback end of the fourth control chip; The first end of the 22nd resistor is electrically connected to the first end of the 9th capacitor, the second end of the 22nd resistor is electrically connected to the first end of the 24th resistor via the 23rd resistor and the 13th capacitor in sequence, and the second end of the 24th resistor is electrically connected to the second end of the second optocoupler.

10. The medical power supply circuit according to claim 9, characterized in that: It also includes a PFC overvoltage protection circuit, a PFC overcurrent protection circuit and a PFC overtemperature protection circuit; The input end of the PFC over-temperature protection circuit is electrically connected to the first voltage output end of the first DC / DC module, and the output end of the PFC over-temperature protection circuit is electrically connected to the induction voltage input end of the first control chip; The input end of the PFC overcurrent protection circuit is electrically connected to the first voltage output end of the first DC / DC module, and the output end of the PFC overcurrent protection circuit is electrically connected to the induction voltage input end of the first control chip; The input end of the PFC overvoltage protection circuit is electrically connected to the correction output end, and the output end of the PFC overvoltage protection circuit is electrically connected to the induced voltage input end of the first control chip; It also includes an output voltage over-temperature protection circuit, an output voltage over-current protection circuit and an output voltage over-voltage protection circuit; The input end of the output voltage over-temperature protection circuit is electrically connected to the first voltage output end of the first DC / DC module, and the output end of the output voltage over-temperature protection circuit is electrically connected to the input end of the drive control module; The input end of the output voltage overcurrent protection circuit is electrically connected to the output end of the first DC / DC module, and the output end of the output voltage overcurrent protection circuit is electrically connected to the input end of the drive control module; The input end of the output voltage overvoltage protection circuit is electrically connected to the output end of the second DC / DC module, and the output end of the output voltage overvoltage protection circuit is electrically connected to the input end of the drive control module.

Images