Intrinsic safety power supply adjusting circuit and adjusting method

Abstract

The invention discloses an intrinsic safety power supply adjusting circuit and an adjusting method. The circuit comprises an electronic current-limiting switch and an electronic shunt switch, the electronic current-limiting switch is connected in series between the cathode of a load and the cathode of an intrinsically safe power supply, and the electronic shunt switch is connected in parallel with the load; the reference source module is provided with reference source output ends with different voltage levels and converts an intrinsic safety power supply into different reference levels; the voltage detection module is provided with a plurality of reference control ends, and controls the reference source module to output a corresponding reference level according to the voltage grade of the intrinsic safety power supply; the power input end of the sampling adjusting module is connected with a corresponding reference level, and the opening degree of the electronic current limiting switch and the opening degree of the electronic shunt switch are controlled according to the corresponding reference level, the feedback of the electronic current limiting switch and the feedback of the electronic shunt switch. The adjusting circuit provided by the invention can adapt to loads with different power supply voltages according to different voltage grades, has a function of balancing line current, and meets the condition of minimum working current of a special line.

Description

Technical Field

[0001] The present invention relates to the technical field of intrinsically safe power supply, and in particular to an intrinsically safe power supply regulating circuit and regulating method. Background Art

[0002] Intrinsically safe power supply is an intrinsically safe power supply, which is an explosion-proof electrical equipment used in dangerous environments with explosive gases. Intrinsically safe power supply requires that under normal working conditions and specified fault conditions, the sparks, arcs and heat generated cannot ignite the specified explosive gas environment. It is suitable for use in scenes with explosion hazards and can provide uninterrupted intrinsically safe DC regulated power supply.

[0003] In order to ensure the safe operation of the intrinsically safe power supply and the load connected to it, a regulating circuit needs to be set up for current regulation. The existing technology generally limits the circuit power by a fixed voltage. For loads with different power supply voltage levels, the regulating circuit cannot adapt to different voltage levels, and the current regulation is limited, which cannot meet the requirements of the minimum working current for special line transmission. Summary of the invention

[0004] The present invention provides an intrinsically safe power supply regulation circuit and regulation method to adapt to loads with different power supply voltage levels, and can also balance line currents to meet the minimum operating current conditions of special lines.

[0005] According to one aspect of the present invention, there is provided an intrinsically safe power supply regulation circuit, comprising:

[0006] An electronic current limiting switch and an electronic shunt switch, wherein the electronic current limiting switch is connected in series between the negative electrode of the load and the negative electrode of the intrinsically safe power supply, and the electronic shunt switch is connected in parallel with the load;

[0007] A reference source module, the input end of which is connected to the intrinsically safe power supply, the reference source module has reference source output ends with different voltage levels, and the reference source module is used to convert the intrinsically safe power supply into reference levels of different segments;

[0008] A voltage detection module, wherein the detection input terminal of the voltage detection module is connected to the intrinsically safe power supply, and the voltage detection module has a plurality of reference control terminals, and the reference control terminals of the voltage detection module are used to control the reference source module to output a corresponding reference level according to the voltage level of the intrinsically safe power supply;

[0009] A sampling and regulating module, wherein the power input terminal of the sampling and regulating module is connected to the corresponding reference level, the current limiting sampling terminal of the sampling and regulating module is coupled to the electronic current limiting switch, the shunt sampling terminal of the sampling and regulating module is coupled to the electronic shunt switch, the current limiting output terminal of the sampling and regulating module is coupled to the control input terminal of the electronic current limiting switch, and the shunt output terminal of the sampling and regulating module is coupled to the control input terminal of the electronic shunt switch; the sampling and regulating module is used to control the opening of the electronic current limiting switch and the opening of the electronic shunt switch according to the corresponding reference level, the feedback of the electronic current limiting switch and the feedback of the electronic shunt switch.

[0010] Optionally, the reference source module includes:

[0011] A first operational amplifier unit includes a first operational amplifier, a first resistor, a second resistor, a third resistor and a fourth resistor, wherein a first input terminal of the first operational amplifier is grounded through the first resistor, a second input terminal of the first operational amplifier is connected to a positive electrode of the intrinsically safe power supply through the second resistor, the third resistor is connected between the first input terminal and an output terminal of the first operational amplifier, the output terminal of the first operational amplifier is coupled to a first terminal of the fourth resistor, and a second terminal of the fourth resistor serves as an output terminal of the first operational amplifier unit;

[0012] A first voltage stabilizer, wherein a positive terminal of the first voltage stabilizer is grounded, a negative terminal of the first voltage stabilizer is coupled to a regulating terminal, and the negative terminal of the first voltage stabilizer is coupled to an output terminal of the first operational amplifier unit; and the regulating terminal of the first voltage stabilizer is coupled to a second input terminal of the first operational amplifier;

[0013] The voltage divider units of multiple channels have an input end coupled to the output end of the first operational amplifier unit, an output end of each voltage divider unit coupled to the power input end of the sampling and regulating module, and a control end of the voltage divider unit coupled to the corresponding reference control end of the voltage detection module.

[0014] Optionally, the voltage dividing unit includes:

[0015] a fifth resistor and a sixth resistor, wherein the fifth resistor and the sixth resistor are connected in series between the positive terminal and the negative terminal of the first voltage regulator;

[0016] A first switch tube and a seventh resistor, wherein the control electrode of the first switch tube serves as the control end of the voltage divider unit, the first electrode of the first switch tube is coupled to the connection node between the fifth resistor and the sixth resistor, and the second electrode of the first switch tube serves as the output end of the voltage divider unit.

[0017] Optionally, the voltage detection module includes:

[0018] Multiple window comparison units, the first voltage input terminal of each window comparison unit is used as the detection input terminal of the voltage detection module, the second voltage input terminal of each window comparison unit is connected to the lower limit reference voltage of the corresponding voltage level, the third voltage input terminal of each window comparison unit is connected to the corresponding upper limit reference voltage, and the output terminals of each window comparison unit are respectively used as the reference control terminals of the voltage detection module.

[0019] Optionally, the window comparison unit includes:

[0020] a first comparator and an eighth resistor, wherein the first input terminal of the first comparator is coupled to the second voltage input terminal of the window comparison unit through the eighth resistor, and the second input terminal of the first comparator is coupled to the first voltage input terminal of the window comparison unit;

[0021] a second comparator and a ninth resistor, wherein a first input terminal of the second comparator is coupled to a first voltage input terminal of the window comparison unit, and a second input terminal of the second comparator is coupled to a third voltage input terminal of the window comparison unit through the ninth resistor;

[0022] A tenth resistor, wherein a first end of the tenth resistor is connected to a control power supply, and a second end of the tenth resistor, an output end of the first comparator and an output end of the second comparator are all coupled to an output end of the window comparison unit.

[0023] Optionally, the sampling and regulating module includes a current limiting sampling and regulating unit, and the current limiting sampling and regulating unit includes:

[0024] A sampling subunit, wherein a sampling terminal of the sampling subunit is coupled to the electronic current limiting switch, and a comparison terminal of the sampling subunit is connected to a corresponding reference level;

[0025] A first current limiting regulating subunit, wherein a power input terminal of the first current limiting regulating subunit is connected to the corresponding reference level, a feedback terminal of the first current limiting regulating subunit is coupled to a sampling terminal of the sampling subunit, a control terminal of the first current limiting regulating subunit is coupled to an output terminal of the sampling subunit, and an output terminal of the first current limiting regulating subunit is coupled to a control terminal of the electronic current limiting switch;

[0026] A second current limiting regulating subunit, wherein the control end of the second current limiting regulating subunit is coupled to the output end of the sampling subunit, and the output end of the second current limiting regulating subunit is coupled to the control end of the electronic current limiting switch.

[0027] Optionally, the sampling subunit includes an eleventh resistor, a second operational amplifier, a twelfth resistor, a thirteenth resistor, a third operational amplifier, a fourteenth resistor, a fifteenth resistor, and a third comparator; the first end of the eleventh resistor is coupled to the electronic current limiting switch and serves as a sampling end of the sampling subunit; the second end of the eleventh resistor is grounded; the first input end of the second operational amplifier is connected to the corresponding reference level through the twelfth resistor and serves as a comparison end of the sampling subunit; the second input end of the second operational amplifier is coupled to its output end through the thirteenth resistor; the first input end of the third operational amplifier is coupled to the first end of the eleventh resistor through the fourteenth resistor, and the second input end of the third operational amplifier is coupled to its output end through the fifteenth resistor; the first input end and the second input end of the third comparator are respectively coupled to the output ends of the second operational amplifier and the third operational amplifier, and the output end of the third comparator serves as the output end of the sampling subunit;

[0028] And / or, the first current limiting regulation subunit includes a fourth operational amplifier and a first MOS tube, the first input end of the fourth operational amplifier is connected to the corresponding reference level, the second input end of the fourth operational amplifier is coupled to the sampling end of the sampling subunit, the output end of the fourth operational amplifier is coupled to the first electrode of the first MOS tube, the gate of the first MOS tube is coupled to the output end of the sampling subunit, and the second electrode of the first MOS tube is coupled to the control end of the electronic current limiting switch;

[0029] And / or, the second current limiting regulation subunit includes a first transistor, a second MOS transistor and a sixteenth resistor, the base of the first transistor is coupled to the output end of the sampling subunit, the first electrode of the first transistor is connected to the control power supply, the second electrode of the first transistor is grounded through the sixteenth resistor and coupled to the gate of the second MOS transistor; the first electrode of the second MOS transistor is connected to the control power supply, and the second electrode of the second MOS transistor is coupled to the control end of the electronic current limiting switch.

[0030] Optionally, the sampling and regulating module includes a shunt sampling and regulating unit, and the shunt sampling and regulating unit includes:

[0031] a fifth operational amplifier and a seventeenth resistor, wherein the first input terminal of the fifth operational amplifier is connected to the corresponding reference level, and the second input terminal of the fifth operational amplifier is coupled to the negative terminal of the load; and the output terminal of the fifth operational amplifier is coupled to the control terminal of the electronic shunt switch through the seventeenth resistor;

[0032] An eighteenth resistor, a first end of the eighteenth resistor is coupled to the first input end of the fifth operational amplifier, and a second end of the eighteenth resistor is grounded.

[0033] Optionally, the sampling and regulating module includes a current limiting sampling and regulating unit and a current dividing sampling and regulating unit;

[0034] The current limiting sampling and adjustment unit and the current shunt sampling and adjustment unit share the reference source module; or, the reference source module includes a first reference source unit and a second reference source unit with the same circuit structure, the first reference source unit is used to provide a reference level to the current limiting sampling and adjustment unit, and the second reference source unit is used to provide a reference level to the current shunt sampling and adjustment unit.

[0035] According to another aspect of the present invention, there is provided an intrinsically safe power supply regulation method, which is applied to the intrinsically safe power supply regulation circuit as described in any embodiment of the present invention.

[0036] The technical solution provided by the embodiment of the present invention can convert the intrinsically safe power supply into reference levels of different segments according to different voltages in the adjustment circuit by setting a voltage detection module and a reference source module, and control the electronic current limiting switch and the electronic shunt switch through the sampling adjustment module, thereby realizing current regulation and power regulation of the load, and also has the function of balancing the line current, meeting the minimum working current conditions of special lines. Therefore, for loads with different voltage levels, the adjustment circuit provided by the present application can automatically perform voltage matching and has good applicability. It can also automatically adapt the reference levels of different segments according to different voltage levels, thereby realizing effective control of the electronic current limiting switch and the electronic shunt switch under different voltage levels, and then realizing the regulation of the current and power of the load, with good regulation effect.

[0037] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0039] Figure 1 is a structural schematic diagram of an intrinsically safe power supply regulation circuit provided according to an embodiment of the present invention;

[0040] Figure 2 is a circuit diagram of a reference source module provided according to an embodiment of the present invention;

[0041] Figure 3is a circuit diagram of a voltage detection module provided according to an embodiment of the present invention;

[0042] Figure 4 is a circuit diagram of another reference source module provided according to an embodiment of the present invention;

[0043] Figure 5 is a circuit diagram of an intrinsically safe power supply regulation circuit provided according to an embodiment of the present invention;

[0044] Figure 6 is a circuit diagram of another intrinsically safe power supply regulation circuit provided according to an embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0046] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0047] An embodiment of the present invention provides an intrinsically safe power supply regulating circuit. Figure 1 A schematic diagram of the structure of an intrinsically safe power supply regulation circuit provided by an embodiment of the present invention. Figure 1The intrinsically safe power supply regulation circuit includes: an electronic current limiting switch 2, an electronic shunt switch 1, a reference source module 4, a voltage detection module 3 and a sampling and regulation module 5. The electronic current limiting switch 2 is connected in series between the negative electrode of the load 6 and the negative electrode of the intrinsically safe power supply, and the electronic shunt switch 1 is connected in parallel with the load 6. The input end of the reference source module 4 is connected to the intrinsically safe power supply, and the reference source module 4 has a reference source output end with different voltage levels. The reference source module 4 is used to convert the intrinsically safe power supply into reference levels of different segments. The detection input end of the voltage detection module 3 is connected to the intrinsically safe power supply, and the voltage detection module 3 has multiple reference control ends. The reference control end of the voltage detection module 3 is used to control the reference source module 4 to output the corresponding reference level according to the voltage level of the intrinsically safe power supply. The power input terminal of the sampling and regulating module 5 is connected to the corresponding reference level, the current limiting sampling terminal of the sampling and regulating module 5 is coupled to the electronic current limiting switch 2, the shunt sampling terminal of the sampling and regulating module 5 is coupled to the electronic shunt switch 1, the current limiting output terminal of the sampling and regulating module 5 is coupled to the control input terminal of the electronic current limiting switch 2, and the shunt output terminal of the sampling and regulating module 5 is coupled to the control input terminal of the electronic shunt switch 1; the sampling and regulating module 5 is used to control the opening of the electronic current limiting switch 2 and the opening of the electronic shunt switch 1 according to the corresponding reference level, the feedback of the electronic current limiting switch 2 and the feedback of the electronic shunt switch 1.

[0048] Among them, the intrinsically safe power supply has output voltages of different sizes, which are used to adapt to loads 6 that require different supply voltages. The voltage detection module 3 can be used to detect the output voltage of the intrinsically safe power supply, so as to obtain the output voltage level of the intrinsically safe power supply. Exemplarily, the reference source module 4 can provide different voltage intervals. When the output voltage of the intrinsically safe power supply is within one of the voltage intervals, the voltage level of the intrinsically safe power supply can be obtained. The voltage detection module 3 controls the reference source module 4 to output a reference level corresponding to the voltage level according to the output voltage of the intrinsically safe power supply. Therefore, for intrinsically safe power supplies of different voltage levels, the reference source module 4 can generate different reference levels according to different voltage levels, thereby realizing the control of the sampling and adjustment module 5 on the electronic current limiting switch 2 and the electronic shunt switch 1. Exemplarily, the load 6 can be an APL (Advanced Physical Layer, Ethernet Advanced Physical Layer) switch.

[0049] The electronic shunt switch 1 is used to adjust the power of the load 6. Specifically, the electronic shunt switch 1 can feed back the sampled voltage of the load 6 into the sampling and adjusting module 5, and the sampling and adjusting module 5 controls the opening of the electronic shunt switch 1 according to the reference level output by the reference source module 4 and the sampled voltage fed back. Exemplarily, the sampling and adjusting module 5 can generate a voltage signal to adjust the output current of the electronic shunt switch 1. Through the shunting of the electronic shunt switch 1, the sampled voltage fed back by the electronic shunt switch 1 can be kept consistent with the reference level, thereby achieving power balance of the load 6, keeping the voltage and current of the load 6 in a stable state, thereby ensuring the stable operation of the load 6.

[0050] The electronic current limiting switch 2 is used for current regulation. Specifically, the electronic current limiting switch 2 is connected to the negative electrode of the load 6, and the sampling voltage of the negative electrode of the load 6 can be fed back into the sampling and regulating module 5. The sampling and regulating module 5 controls the opening of the electronic current limiting switch 2 according to the reference level output by the reference source module 4 and the sampling voltage of the negative electrode of the load 6. The current of the load 6 is regulated by the electronic current limiting switch 2, thereby adjusting the voltage of the load 6, so that the reference level and the sampling voltage of the negative electrode of the load 6 are kept consistent, thereby achieving the regulation and limitation of the current, so that when a short circuit occurs in the load 6, the short-circuit current can be limited by the electronic current limiting switch 2, thereby achieving the safe operation of the load 6, so that the current of the load 6 is in a safe current range.

[0051] For some loads 6 with special requirements for working conditions, the transmission current of the line may need to reach the minimum working current of the load 6 to ensure the stable operation of the load 6. Exemplarily, the minimum input current of the load 6 needs to be greater than or equal to 20mA. The embodiment of the present invention sets an electronic shunt switch 1 and an electronic current limiting switch 2, and balances the line current so that the current input to the load 6 is always within a stable range greater than or equal to the minimum working current, thereby ensuring the stable operation of the load 6.

[0052] The technical solution provided in the embodiment of the present invention can convert the intrinsically safe power supply into reference levels of different segments according to different voltages in the adjustment circuit by setting a voltage detection module 3 and a reference source module 4, and control the electronic current limiting switch 2 and the electronic shunt switch 1 through the sampling adjustment module 5, thereby realizing current regulation and power regulation of the load 6, and also has the function of balancing the line current, satisfying the minimum working current condition of the special line. Therefore, for loads 6 with different voltage levels, the adjustment circuit provided in the present application can automatically perform voltage matching and has good applicability. It can also automatically adapt the reference levels of different segments according to different voltage levels, thereby realizing effective control of the electronic current limiting switch 2 and the electronic shunt switch 1 under different voltage levels, and then realizing the regulation of the current and power of the load 6, with good regulation effect.

[0053] Figure 2 A circuit diagram of a reference source module provided by an embodiment of the present invention. Figure 1 and Figure 2 On the basis of the above embodiments, optionally, the reference source module 4 includes: a first operational amplifier unit 41, a first voltage regulator VD1 and a voltage divider unit 42 of multiple channels. The first operational amplifier unit 41 includes a first operational amplifier U1, a first resistor R1, a second resistor R2, a third resistor R3 and a fourth resistor R4. The first input terminal of the first operational amplifier U1 is grounded through the first resistor R1, the second input terminal of the first operational amplifier U1 is connected to the positive electrode of the intrinsically safe power supply through the second resistor R2, the third resistor R3 is connected between the first input terminal and the output terminal of the first operational amplifier U1, the output terminal of the first operational amplifier U1 is coupled to the first terminal of the fourth resistor R4, and the second terminal of the fourth resistor R4 is used as the output terminal of the first operational amplifier unit 41. The first voltage regulator VD1, the positive terminal of the first voltage regulator VD1 is grounded, the negative terminal of the first voltage regulator VD1 is coupled to the adjustment terminal, and the negative terminal of the first voltage regulator VD1 is coupled to the output terminal of the first operational amplifier unit 41; the adjustment terminal of the first voltage regulator VD1 is coupled to the second input terminal of the first operational amplifier U1. The input end of each voltage divider unit 42 is coupled to the output end of the first operational amplifier unit 41 , the output end of each voltage divider unit 42 is coupled to the power input end of the sampling and regulating module 5 , and the control end of the voltage divider unit 42 is coupled to the corresponding reference control end of the voltage detection module 3 .

[0054] Among them, the first operational amplifier U1 is connected to the positive pole of the intrinsically safe power supply for accessing the intrinsically safe power supply, and the first voltage regulator VD1 can adjust the voltage output by the first operational amplifier U1. Exemplarily, the first voltage regulator VD1 can stabilize the output voltage of the intrinsically safe power supply to 1.5V. In order to ensure that the reference source module 4 can effectively adjust the electronic current limiting switch 2 and the electronic shunt switch 1 under different output voltages of the intrinsically safe power supply, the voltage adjusted by the first voltage regulator VD1 needs to be converted into reference levels of different segments according to different output voltages of the intrinsically safe power supply, so as to meet the level requirements of the sampling and adjustment module 5 under different output voltages of the intrinsically safe power supply.

[0055] The voltage divider unit 42 may be provided with a plurality of channels, and the intrinsically safe power supply may be converted into reference levels of different segments through different channels of the voltage divider unit 42, and each reference level corresponds to a different output voltage of the intrinsically safe power supply. By judging the output voltage of the intrinsically safe power supply, a channel in the voltage divider unit 42 may be turned on according to the output voltage, so as to input the reference level to the sampling and adjusting module 5.

[0056] Continue to refer Figure 2On the basis of the above embodiments, optionally, the voltage dividing unit 42 includes: a fifth resistor R5, a sixth resistor R6, a first switch tube Q1 and a seventh resistor R7, and the fifth resistor R5 and the sixth resistor R6 are connected in series between the positive terminal and the negative terminal of the first voltage regulator VD1. The control electrode of the first switch tube Q1 serves as the control end of the voltage dividing unit 42, the first electrode of the first switch tube Q1 is coupled to the connection node of the fifth resistor R5 and the sixth resistor R6, and the second electrode of the first switch tube Q1 serves as the output end of the voltage dividing unit 42.

[0057] The fifth resistor R5 and the sixth resistor R6 are used to divide the voltage between the positive terminal and the negative terminal of the first voltage stabilizer VD1. Figure 2 The voltage divider unit 42 with 6 channels is shown by way of example, and the second channel of the voltage divider unit 42 includes a 19th resistor R19, a 20th resistor R20, a second switch tube Q2, and a 21st resistor R21. The third channel of the voltage divider unit 42 includes a 22nd resistor R22, a 23rd resistor R23, a third switch tube Q3, and a 24th resistor R24. The fourth channel of the voltage divider unit 42 includes a 25th resistor R25, a 26th resistor R26, a fourth switch tube Q4, and a 27th resistor R27. The fifth channel of the voltage divider unit 42 includes a 28th resistor R28, a 29th resistor R29, a fifth switch tube Q5, and a 30th resistor R30. The sixth channel of the voltage divider unit 42 includes a 31st resistor R31, a 32nd resistor R32, a 6th switch tube Q6, and a 33rd resistor R33. Different channels in the voltage divider unit 42 have resistors with different resistance values, so the voltage adjusted by the first voltage regulator VD1 can be divided into six different reference levels.

[0058] Figure 3 A circuit diagram of a voltage detection module provided by an embodiment of the present invention. Figure 1 and Figure 3 On the basis of the above embodiments, optionally, the voltage detection module 3 includes: a plurality of window comparison units 31, the first voltage input terminal of each window comparison unit 31 is used as the detection input terminal of the voltage detection module, the second voltage input terminal of each window comparison unit 31 is connected to the lower limit reference voltage of the corresponding voltage level, the third voltage input terminal of each window comparison unit 31 is connected to the corresponding upper limit reference voltage, and the output terminals of each window comparison unit 31 are respectively used as the reference control terminals of the voltage detection module 3.

[0059] Among them, according to the output voltage of the intrinsically safe power supply, the output voltage can be divided into multiple voltage intervals, and each voltage interval corresponds to a different upper limit reference voltage and lower limit reference voltage. Figure 4 The circuit diagram of another reference source module is shown as an example. Figure 3 and Figure 4, illustratively, the reference source module 4 can be used to divide the output voltage into 6 voltage level intervals. The interval of the first voltage level is divided by the thirty-fourth resistor R34, the thirty-fifth resistor R35 and the thirty-sixth resistor R36, and the lower limit reference voltage V1 and the upper limit reference voltage V2 of the voltage level are output. The interval of the second voltage level is divided by the thirty-seventh resistor R37, the thirty-eighth resistor R38 and the thirty-ninth resistor R39, and the lower limit reference voltage V3 and the upper limit reference voltage V4 of the voltage level are output. The interval of the third voltage level is divided by the fortieth resistor R40, the forty-first resistor R41 and the forty-second resistor R42, and the lower limit reference voltage V5 and the upper limit reference voltage V6 of the voltage level are output. The interval of the fourth voltage level is divided by the forty-third resistor R43, the forty-fourth resistor R44 and the forty-fifth resistor R45, and the lower limit reference voltage V7 and the upper limit reference voltage V8 of the voltage level are output. The interval of the fifth voltage level is divided by the 46th resistor R46, the 47th resistor R47 and the 48th resistor R48, and the lower limit reference voltage V9 and the upper limit reference voltage V10 of the voltage level are output. The interval of the sixth voltage level is divided by the 49th resistor R49, the 50th resistor R50 and the 51st resistor R52, and the lower limit reference voltage V11 and the upper limit reference voltage V12 of the voltage level are output.

[0060] For example, when the output voltage of the intrinsically safe power supply is 9-15V, the lower limit reference voltage V1 can be 9V, and the upper limit reference voltage V2 can be 10V; the lower limit reference voltage V3 can be 10V, and the upper limit reference voltage V4 can be 11V; the lower limit reference voltage V3 can be 11V, and the upper limit reference voltage V4 can be 12V; the lower limit reference voltage V5 can be 12V, and the upper limit reference voltage V6 can be 13V; the lower limit reference voltage V7 can be 13V, and the upper limit reference voltage V8 can be 14V; the lower limit reference voltage V9 can be 14V, and the upper limit reference voltage V10 can be 15V.

[0061] Each window comparison unit 31 is connected to an upper limit reference voltage and a lower limit reference voltage of a voltage interval. When the voltage detected by the first voltage input terminal of one of the window comparison units 31 is exactly within the range of the upper limit reference voltage and the lower limit reference voltage, the window comparison unit 31 controls the channel corresponding to the voltage divider unit 42 to be turned on.

[0062] Figure 5 A circuit diagram of an intrinsically safe power supply regulation circuit provided by an embodiment of the present invention. Figure 5On the basis of the above embodiments, optionally, the window comparison unit 31 includes: a first comparator UA1, an eighth resistor R8, a second comparator UA2, a ninth resistor R9 and a tenth resistor R10. The first input terminal of the first comparator U1A is coupled to the second voltage input terminal of the window comparison unit 31 through the eighth resistor R8, and the second input terminal of the first comparator UA1 is coupled to the first voltage input terminal of the window comparison unit 31. The first input terminal of the second comparator UA2 is coupled to the first voltage input terminal of the window comparison unit 31, and the second input terminal of the second comparator UA2 is coupled to the third voltage input terminal of the window comparison unit 31 through the ninth resistor R9. The first terminal of the tenth resistor R10 is connected to the control power supply, and the second terminal of the tenth resistor R10, the output terminal of the first comparator UA1 and the output terminal of the second comparator UA2 are all coupled to the output terminal of the window comparison unit 31.

[0063] The window comparison unit 31 is used to control the on and off of each switch tube in the voltage divider unit. Therefore, the number of window comparison units 31 is the same as the number of switch tubes, and each window comparison unit 31 controls one switch tube. Each window comparison unit 31 has the same structure. For example, the window comparison unit 31 for controlling the second switch tube Q2 includes a fourth comparator UA4, a fifty-second resistor R52, a fifth comparator UA5, a fifty-third resistor R53, and a fifty-fourth resistor R54. Figure 5 The case of six switch tubes is exemplarily shown, and two window comparison units 31 are shown, and the structures of the remaining four window comparison units 31 are the same as the structure of the window comparison unit 31 shown.

[0064] Exemplarily, when the voltage input to the first comparator UA1 at the second voltage input terminal of the window comparison unit 31 is 10V, and the voltage input to the second comparator UA2 at the third voltage input terminal of the window comparison unit 31 is 11V, if the input voltage at the first voltage input terminal of the window comparison unit 31 is not within the range of 10-11V, the output terminal of the window comparison unit 31 outputs a control signal to control the first switch tube Q1 to be turned off. If the input voltage at the first voltage input terminal of the window comparison unit 31 is just within the range of 10-11V, the output terminal of the window comparison unit 31 outputs a control signal to control the first switch tube Q1 to be turned on, and the reference source module 4 inputs the reference level of the segment to the sampling and adjustment module through the first switch tube Q1.

[0065] Continue to refer Figure 5On the basis of the above embodiments, optionally, the sampling and regulating module includes a current limiting sampling and regulating unit 51, and the current limiting sampling and regulating unit 51 includes: a sampling subunit 511, a first current limiting regulating subunit 512, and a second current limiting regulating subunit 513. The sampling end of the sampling subunit 511 is coupled to the electronic current limiting switch 2, and the comparison end of the sampling subunit 511 is connected to the corresponding reference level. The power input end of the first current limiting regulating subunit 512 is connected to the corresponding reference level, the feedback end of the first current limiting regulating subunit 512 is coupled to the sampling end of the sampling subunit 511, the control end of the first current limiting regulating subunit 512 is coupled to the output end of the sampling subunit 511, and the output end of the first current limiting regulating subunit 512 is coupled to the control end of the electronic current limiting switch 2. The control end of the second current limiting regulating subunit 513 is coupled to the output end of the sampling subunit 511, and the output end of the second current limiting regulating subunit 513 is coupled to the control end of the electronic current limiting switch 2.

[0066] Among them, the current limiting sampling and adjustment unit 51 is used to control the opening of the electronic current limiting switch 2. The sampling subunit 511 can compare the reference level with the sampling voltage fed back by the electronic current limiting switch 2. When the sampling voltage of the electronic current limiting switch 2 is less than the reference level, it means that the current flowing through the load 6 does not exceed the set value, and there is no fault in the intrinsically safe power supply and the load 6. The sampling subunit 511 can output a control signal and enable the second current limiting adjustment subunit 513 to adjust the opening of the electronic current limiting switch 2 to increase the opening of the electronic current limiting switch 2 so that the current of the load 6 is maintained in a better state.

[0067] When the feedback level of the electronic current limiting switch 2 is greater than the reference level, it indicates that the current flowing through the load 6 is too large, and the load 6 may be short-circuited, and the output current of the electronic current limiting switch 2 needs to be controlled to reduce the current. The sampling subunit 511 can output a control signal and turn on the first current limiting adjustment subunit 512, and the first current limiting adjustment subunit 512 adjusts the opening of the electronic current limiting switch 2 and reduces the opening of the electronic current limiting switch 2, thereby reducing the current in the circuit.

[0068] Continue to refer Figure 5On the basis of the above embodiments, optionally, the sampling subunit 511 includes an eleventh resistor R11, a second operational amplifier U2, a twelfth resistor R12, a thirteenth resistor R13, a third operational amplifier, a fourteenth resistor R14, a fifteenth resistor R15 and a third comparator U3. The first end of the eleventh resistor R11 is coupled to the electronic current limiting switch 2 and serves as the sampling end of the sampling subunit 511; the second end of the eleventh resistor R11 is grounded; the first input end of the second operational amplifier U2 is connected to the corresponding reference level through the twelfth resistor R12 and serves as the comparison end of the sampling subunit 511; the second input end of the second operational amplifier U2 is coupled to its output end through the thirteenth resistor R13; the first input end of the third operational amplifier U3 is coupled to the first end of the eleventh resistor R11 through the fourteenth resistor R14, and the second input end of the third operational amplifier U3 is coupled to its output end through the fifteenth resistor R15; the first input end and the second input end of the third comparator UA3 are coupled to the output ends of the second operational amplifier U2 and the third operational amplifier U3 respectively, and the output end of the third comparator UA3 serves as the output end of the sampling subunit 511.

[0069] Among them, the second operational amplifier U2 is used to sample the reference level and input it into the first input terminal of the third comparator UA3, and the third operational amplifier U3 is used to obtain the actual voltage of the sampling terminal and input it into the second input terminal of the third comparator UA3. The third comparator UA3 can judge whether the current flowing through the load 6 is normal according to the relationship between the reference level and the actual voltage. When the actual voltage is greater than the reference level, the load 6 has an overcurrent, and the third comparator UA3 controls the first current limiting adjustment subunit 512 to adjust the opening of the electronic current limiting switch 2 and reduce the opening of the electronic current limiting switch 2. When the actual voltage is less than the reference level, the load 6 does not have an overcurrent, and the third comparator UA3 controls the second current limiting adjustment subunit 513 to adjust the opening of the electronic current limiting switch 2 and increase the opening of the electronic current limiting switch 2.

[0070] Continue to refer Figure 5 On the basis of the above embodiments, optionally, the first current limiting regulating subunit 512 includes a fourth operational amplifier U4 and a first MOS tube M1, the first input end of the fourth operational amplifier U4 is connected to the corresponding reference level, the first input end of the fourth operational amplifier U4 is also connected to the fifty-fifth resistor R55, the second input end of the fourth operational amplifier U4 is coupled to the sampling end of the sampling subunit 511, the output end of the fourth operational amplifier U4 is coupled to the first electrode of the first MOS tube M1, the gate of the first MOS tube M1 is coupled to the output end of the sampling subunit 511 through the fifty-seventh resistor R57, and the gate of the first MOS tube M1 is also connected to the fifty-eighth resistor R58. The second electrode of the first MOS tube M1 is coupled to the control end of the electronic current limiting switch 2 through the fifty-sixth resistor R56.

[0071] Exemplarily, when the load 6 has an overcurrent, the third comparator UA3 generates a high level signal and inputs it to the gate of the first MOS tube M1, which may be an NMOS tube. The first MOS tube M1 is turned on according to the high level signal. The fourth operational amplifier U4 generates different output voltages according to the reference level of the first input terminal and the actual voltage obtained by the second input terminal, thereby reducing the opening of the electronic current limiting switch 2, thereby limiting the output current of the electronic current limiting switch 2.

[0072] When there is no overcurrent in the load 6, the third comparator UA3 generates a low level signal and inputs it to the gate of the first MOS tube M1. The first MOS tube M1 is turned off according to the low level signal. The output voltage of the fourth operational amplifier U4 cannot be input into the electronic current limiting switch 2, and the fourth operational amplifier U4 cannot control the electronic current limiting switch 2.

[0073] Continue to refer Figure 5 On the basis of the above embodiments, optionally, the second current limiting regulating subunit 513 includes a first transistor D1, a second MOS transistor M2 and a sixteenth resistor R16, the base of the first transistor D1 is coupled to the output end of the sampling subunit 511, the first electrode of the first transistor D1 is connected to the control power supply, the second electrode of the first transistor D1 is grounded through the sixteenth resistor R16, and is coupled to the gate of the second MOS transistor M2; the first electrode of the second MOS transistor M2 is connected to the control power supply, and the second electrode of the second MOS transistor M2 is coupled to the control end of the electronic current limiting switch 2.

[0074] Exemplarily, when the load 6 has an overcurrent, the third comparator UA3 generates a high-level signal and inputs it to the gate of the first MOS transistor M1. At the same time, the signal is input to the base of the first transistor D1. The first transistor D1 can be a PNP transistor, and the second MOS transistor M2 can be an NMOS transistor. The first transistor D1 is turned off according to the high-level signal, and the gate of the second MOS transistor M2 is converted from a high level to a low level, so that the second MOS transistor M2 turns off the control of the electronic current limiting switch 2.

[0075] When the load 6 does not have overcurrent, the third comparator UA3 generates a low-level signal and inputs it to the gate of the first MOS tube M1. At the same time, the signal is input to the base of the first transistor D1. The first transistor D1 is turned on according to the low-level signal, and the gate of the second MOS tube M2 is also turned on at a high level, thereby increasing the opening of the electronic current limiting switch 2, thereby achieving balanced regulation of the current.

[0076] Continue to refer Figure 5On the basis of the above embodiments, the sampling and regulating module may optionally include a shunt sampling and regulating unit 52, and the shunt sampling and regulating unit 52 includes: a fifth operational amplifier U5, a seventeenth resistor R17, and an eighteenth resistor R18. The first input terminal of the fifth operational amplifier U5 is connected to the corresponding reference level, and the second input terminal of the fifth operational amplifier U5 is coupled to the negative terminal of the load 6; the output terminal of the fifth operational amplifier U5 is coupled to the control terminal of the electronic shunt switch 1 through the seventeenth resistor R17. The first terminal of the eighteenth resistor R18 is coupled to the first input terminal of the fifth operational amplifier U5, and the second terminal of the eighteenth resistor R18 is grounded.

[0077] The first input terminal of the fifth operational amplifier U5 is used to sample the reference level, and the second input terminal of the fifth operational amplifier U5 is used to sample the voltage at the negative terminal of the load 6. The fifth operational amplifier U5 uses its own virtual short and virtual open characteristics to adjust the output voltage of the fifth operational amplifier U5, thereby controlling the output current of the electronic shunt switch 1. When the voltages at the first input terminal and the second input terminal of the fifth operational amplifier U5 are the same, the power of the load 6 is balanced, and the fifth operational amplifier U5 completes the adjustment of the power of the load 6.

[0078] Continue to refer Figure 5 On the basis of the above embodiments, optionally, the sampling and regulating module includes a current limiting sampling and regulating unit 51 and a current shunt sampling and regulating unit 52. The current limiting sampling and regulating unit 51 and the current shunt sampling and regulating unit 52 share the reference source module 4. Figure 6 The circuit diagram of another intrinsically safe power supply regulation circuit is shown as an example. Figure 6 The reference source module 4 includes a first reference source unit 401 and a second reference source unit 402 with the same circuit structure. The first reference source unit 401 is used to provide a reference level to the current limiting sampling and adjustment unit 51, and the second reference source unit 402 is used to provide a reference level to the current shunt sampling and adjustment unit 52.

[0079] An embodiment of the present invention further provides an intrinsically safe power supply regulation method, which is applied to an intrinsically safe power supply regulation circuit provided by any embodiment of the present invention and has similar beneficial effects as the intrinsically safe power supply regulation circuit provided by any of the above embodiments, and will not be described in detail here.

[0080] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0081] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An intrinsically safe power supply regulation circuit, characterized in that: include: An electronic current limiting switch and an electronic shunt switch, wherein the electronic current limiting switch is connected in series between the negative electrode of the load and the negative electrode of the intrinsically safe power supply, and the electronic shunt switch is connected in parallel with the load; A reference source module, the input end of which is connected to the intrinsically safe power supply, the reference source module has reference source output ends with different voltage levels, and the reference source module is used to convert the intrinsically safe power supply into reference levels of different segments; A voltage detection module, wherein the detection input terminal of the voltage detection module is connected to the intrinsically safe power supply, and the voltage detection module has a plurality of reference control terminals, and the reference control terminals of the voltage detection module are used to control the reference source module to output a corresponding reference level according to the voltage level of the intrinsically safe power supply; A sampling and regulating module, wherein the power input terminal of the sampling and regulating module is connected to the corresponding reference level, the current limiting sampling terminal of the sampling and regulating module is coupled to the electronic current limiting switch, the shunt sampling terminal of the sampling and regulating module is coupled to the electronic shunt switch, the current limiting output terminal of the sampling and regulating module is coupled to the control input terminal of the electronic current limiting switch, and the shunt output terminal of the sampling and regulating module is coupled to the control input terminal of the electronic shunt switch; the sampling and regulating module is used to control the opening of the electronic current limiting switch and the opening of the electronic shunt switch according to the corresponding reference level, the feedback of the electronic current limiting switch and the feedback of the electronic shunt switch.

2. The intrinsically safe power supply regulating circuit according to claim 1, characterized in that: The reference source module comprises: A first operational amplifier unit includes a first operational amplifier, a first resistor, a second resistor, a third resistor and a fourth resistor, wherein a first input terminal of the first operational amplifier is grounded through the first resistor, a second input terminal of the first operational amplifier is connected to a positive electrode of the intrinsically safe power supply through the second resistor, the third resistor is connected between the first input terminal and an output terminal of the first operational amplifier, the output terminal of the first operational amplifier is coupled to a first terminal of the fourth resistor, and a second terminal of the fourth resistor serves as an output terminal of the first operational amplifier unit; A first voltage stabilizer, wherein a positive terminal of the first voltage stabilizer is grounded, a negative terminal of the first voltage stabilizer is coupled to a regulating terminal, and the negative terminal of the first voltage stabilizer is coupled to an output terminal of the first operational amplifier unit; and the regulating terminal of the first voltage stabilizer is coupled to a second input terminal of the first operational amplifier; The voltage divider units of multiple channels have an input end coupled to the output end of the first operational amplifier unit, an output end of each voltage divider unit coupled to the power input end of the sampling and regulating module, and a control end of the voltage divider unit coupled to the corresponding reference control end of the voltage detection module.

3. The intrinsically safe power supply regulating circuit according to claim 2, characterized in that: The voltage dividing unit comprises: a fifth resistor and a sixth resistor, wherein the fifth resistor and the sixth resistor are connected in series between the positive terminal and the negative terminal of the first voltage regulator; A first switch tube and a seventh resistor, wherein the control electrode of the first switch tube serves as the control end of the voltage divider unit, the first electrode of the first switch tube is coupled to the connection node between the fifth resistor and the sixth resistor, and the second electrode of the first switch tube serves as the output end of the voltage divider unit.

4. The intrinsically safe power supply regulating circuit according to claim 1, characterized in that: The voltage detection module comprises: Multiple window comparison units, the first voltage input terminal of each window comparison unit is used as the detection input terminal of the voltage detection module, the second voltage input terminal of each window comparison unit is connected to the lower limit reference voltage of the corresponding voltage level, the third voltage input terminal of each window comparison unit is connected to the corresponding upper limit reference voltage, and the output terminals of each window comparison unit are respectively used as the reference control terminals of the voltage detection module.

5. The intrinsically safe power supply regulating circuit according to claim 4, characterized in that: The window comparison unit comprises: a first comparator and an eighth resistor, wherein the first input terminal of the first comparator is coupled to the second voltage input terminal of the window comparison unit through the eighth resistor, and the second input terminal of the first comparator is coupled to the first voltage input terminal of the window comparison unit; a second comparator and a ninth resistor, wherein a first input terminal of the second comparator is coupled to a first voltage input terminal of the window comparison unit, and a second input terminal of the second comparator is coupled to a third voltage input terminal of the window comparison unit through the ninth resistor; A tenth resistor, wherein a first end of the tenth resistor is connected to a control power supply, and a second end of the tenth resistor, an output end of the first comparator and an output end of the second comparator are all coupled to an output end of the window comparison unit.

6. The intrinsically safe power supply regulating circuit according to claim 1, characterized in that: The sampling and regulating module includes a current limiting sampling and regulating unit, and the current limiting sampling and regulating unit includes: A sampling subunit, wherein a sampling terminal of the sampling subunit is coupled to the electronic current limiting switch, and a comparison terminal of the sampling subunit is connected to a corresponding reference level; A first current limiting regulating subunit, wherein a power input terminal of the first current limiting regulating subunit is connected to the corresponding reference level, a feedback terminal of the first current limiting regulating subunit is coupled to a sampling terminal of the sampling subunit, a control terminal of the first current limiting regulating subunit is coupled to an output terminal of the sampling subunit, and an output terminal of the first current limiting regulating subunit is coupled to a control terminal of the electronic current limiting switch; A second current limiting regulating subunit, wherein the control end of the second current limiting regulating subunit is coupled to the output end of the sampling subunit, and the output end of the second current limiting regulating subunit is coupled to the control end of the electronic current limiting switch.

7. The intrinsically safe power supply regulating circuit according to claim 6, characterized in that: The sampling subunit includes an eleventh resistor, a second operational amplifier, a twelfth resistor, a thirteenth resistor, a third operational amplifier, a fourteenth resistor, a fifteenth resistor, and a third comparator; a first end of the eleventh resistor is coupled to the electronic current limiting switch and serves as a sampling end of the sampling subunit; a second end of the eleventh resistor is grounded; a first input end of the second operational amplifier is connected to a corresponding reference level through the twelfth resistor and serves as a comparison end of the sampling subunit; The second input terminal of the second operational amplifier is coupled to the output terminal thereof through the thirteenth resistor; the first input terminal of the third operational amplifier is coupled to the first terminal of the eleventh resistor through the fourteenth resistor, and the second input terminal of the third operational amplifier is coupled to the output terminal thereof through the fifteenth resistor; the first input terminal and the second input terminal of the third comparator are coupled to the output terminals of the second operational amplifier and the third operational amplifier, respectively, and the output terminal of the third comparator serves as the output terminal of the sampling subunit; And / or, the first current limiting regulation subunit includes a fourth operational amplifier and a first MOS tube, the first input end of the fourth operational amplifier is connected to the corresponding reference level, the second input end of the fourth operational amplifier is coupled to the sampling end of the sampling subunit, the output end of the fourth operational amplifier is coupled to the first electrode of the first MOS tube, the gate of the first MOS tube is coupled to the output end of the sampling subunit, and the second electrode of the first MOS tube is coupled to the control end of the electronic current limiting switch; And / or, the second current limiting regulation subunit includes a first transistor, a second MOS transistor and a sixteenth resistor, the base of the first transistor is coupled to the output end of the sampling subunit, the first electrode of the first transistor is connected to the control power supply, the second electrode of the first transistor is grounded through the sixteenth resistor and coupled to the gate of the second MOS transistor; the first electrode of the second MOS transistor is connected to the control power supply, and the second electrode of the second MOS transistor is coupled to the control end of the electronic current limiting switch.

8. The intrinsically safe power supply regulating circuit according to claim 1, characterized in that: The sampling and regulating module includes a shunt sampling and regulating unit, and the shunt sampling and regulating unit includes: a fifth operational amplifier and a seventeenth resistor, wherein the first input terminal of the fifth operational amplifier is connected to the corresponding reference level, and the second input terminal of the fifth operational amplifier is coupled to the negative terminal of the load; and the output terminal of the fifth operational amplifier is coupled to the control terminal of the electronic shunt switch through the seventeenth resistor; An eighteenth resistor, a first end of the eighteenth resistor is coupled to the first input end of the fifth operational amplifier, and a second end of the eighteenth resistor is grounded.

9. The intrinsically safe power supply regulating circuit according to claim 1, characterized in that: The sampling and regulating module includes a current limiting sampling and regulating unit and a current dividing sampling and regulating unit; The current limiting sampling and adjustment unit and the current shunt sampling and adjustment unit share the reference source module; or, the reference source module includes a first reference source unit and a second reference source unit with the same circuit structure, the first reference source unit is used to provide a reference level to the current limiting sampling and adjustment unit, and the second reference source unit is used to provide a reference level to the current shunt sampling and adjustment unit.

10. A method for regulating an intrinsically safe power supply, characterized in that: Applicable to the intrinsically safe power supply regulation circuit as described in any one of claims 1 to 9.

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