Isolation control circuit and resonant converter

Abstract

The embodiment of the utility model discloses an isolation control circuit and a resonant converter. The isolation control circuit comprises a first control module and a second control module, the input end of the first control module is connected with the sampling end of the low-voltage side so as to obtain sampling data of the low-voltage side; the input end of the second control module is connected with the sampling end of the high-voltage side to obtain sampling data of the high-voltage side, and the low-voltage side and the high-voltage side are the low-voltage side and the high-voltage side of the voltage transformation module respectively; the communication end of the first control module is in communication connection with the communication end of the second control module, and sampling data interaction is carried out between the second control module and the first control module through the communication ends. According to the embodiment of the utility model, the low-voltage side and the high-voltage side of the transformation module are respectively provided with one control module so as to independently sample and drive the low-voltage side and the high-voltage side, thereby avoiding the use of an isolation driving chip and an isolation sampling chip, improving the reliability of the isolation control circuit, and reducing the cost.

Description

Technical Field

[0001] The embodiments of the utility model relate to the field of inverter isolation, and in particular to an isolation control circuit and a resonant converter. Background Art

[0002] Devices such as inverters, variable frequency drives (VFDs), uninterruptible power supplies (UPS), and various switching power supplies including LLC resonant converters require signal and control isolation between the high-voltage and low-voltage sides to ensure safety and efficiency.

[0003] The current fully isolated control scheme and the corresponding auxiliary power supply design have the following characteristics: the high-voltage side and the low-voltage side share an MCU. The driving signal and sampling signal on the high-voltage side are directly sent and received by the MCU, while the driving signal and sampling signal on the low-voltage side must be sent and received indirectly through the isolation element. The flyback transformer is used to provide power supply. In addition, the LLC resonant converter circuit also requires the use of a resonant transformer.

[0004] The above solution has the following disadvantages: the control and sampling of the low-voltage side must use an isolated driver chip and an isolated sampling chip, which have high requirements for the frequency and accuracy of the isolation components and are also expensive; the flyback transformer circuit is complex, the debugging of the auxiliary source activation circuit is time-consuming, and it is prone to failure and difficult to troubleshoot. In addition, the flyback power supply will occupy a large PCBA area. Utility Model Content

[0005] The main technical problem solved by the embodiments of the present utility model is to provide an isolation control circuit and a resonant converter, which can solve the problem caused by the necessity of using an isolation drive chip and an isolation sampling chip for control and sampling on the low-voltage side.

[0006] In order to solve the above technical problems, a technical solution adopted by the present invention is: to provide an isolation control circuit, including: a first control module and a second control module; the input end of the first control module is connected to the sampling end of the low-voltage side to obtain the sampling data of the low-voltage side; the input end of the second control module is connected to the sampling end of the high-voltage side to obtain the sampling data of the high-voltage side, wherein the low-voltage side and the high-voltage side are respectively the low-voltage side and the high-voltage side of the transformer module; the communication end of the first control module is communicatively connected to the communication end of the second control module, and the second control module and the first control module exchange sampling data through the communication end.

[0007] In some embodiments, the output end of the first control module is connected to the driving end of the low-voltage side to output a first driving signal to drive the low-voltage side; the output end of the second control module is connected to the driving end of the high-voltage side to output a second driving signal to drive the high-voltage side.

[0008] In some embodiments, the isolation control circuit also includes: an auxiliary power supply module for powering the first control module and the second control module; the first input end of the auxiliary power supply module is connected to the low-voltage side, the second input end of the auxiliary power supply module is connected to the high-voltage side, the first output end of the auxiliary power supply module is connected to the input end of the first control module, the second output end of the auxiliary power supply module is connected to the input end of the second control module, and the signal input end of the auxiliary power supply module is respectively connected to the control device, the power grid and the photovoltaic system.

[0009] In some embodiments, the first control module includes a first control unit, a first operational amplifier sampling unit, a first Hall sampling unit and a first driving unit; the communication end of the first control unit is communicatively connected to the communication end of the second control module, the first input end of the first control unit is connected to the output end of the first operational amplifier sampling unit, the second input end of the first control unit is connected to the output end of the first Hall sampling unit, and the output end of the first control unit is connected to the input end of the first driving unit; the input end of the first operational amplifier sampling unit is connected to the first sampling end of the low-voltage side, the input end of the first Hall sampling unit is connected to the second sampling end of the low-voltage side, and the output end of the first driving unit is connected to the driving end of the low-voltage side; the first operational amplifier sampling unit is used to obtain voltage sampling data of the low-voltage side, the first Hall sampling unit is used to obtain current sampling data of the low-voltage side, the first control unit is used to output a first control signal, and the first driving unit is used to output the first driving signal to the low-voltage side according to the first control signal.

[0010] In some embodiments, the second control module includes a second control unit, a second operational amplifier sampling unit, a second Hall sampling unit, a current mutual sensing unit and a second drive unit; the communication end of the second control unit is communicatively connected to the communication end of the first control module, the first input end of the second control unit is connected to the output end of the second operational amplifier sampling unit, the second input end of the second control unit is connected to the output end of the second Hall sampling unit, the third input end of the second control unit is connected to the output end of the current mutual sensing unit, and the output end of the second control unit is connected to the input end of the second drive unit; the input end of the second operational amplifier sampling unit is connected to the first sampling end of the high-voltage side, the input end of the second Hall sampling unit is connected to the second sampling end of the high-voltage side, the input end of the current mutual sensing unit is connected to the third sampling end of the high-voltage side, and the output end of the second drive unit is connected to the drive end of the high-voltage side; the second operational amplifier sampling unit is used to obtain voltage sampling data of the high-voltage side, the second Hall sampling unit and the current mutual sensing unit are used to obtain current sampling data of the high-voltage side, the second control unit is used to output a second control signal, and the second drive unit is used to output the second drive signal to the high-voltage side according to the second control signal.

[0011] In some embodiments, the second control unit includes a controller and an isolation communication chip; the first communication end of the isolation communication chip is connected to the communication end of the first control module, the second communication end of the isolation communication chip is connected to the communication end of the controller, the first input end of the controller is connected to the output end of the second op amp sampling unit, the second input end of the controller is connected to the output end of the second Hall sampling unit, the third input end of the controller is connected to the output end of the current mutual induction unit, and the output end of the controller is connected to the input end of the second drive unit.

[0012] In some embodiments, the auxiliary power supply module includes a first conversion unit, a second conversion unit and an activation unit; the first input end of the second conversion unit is connected to the low-voltage side, the second input end of the second conversion unit is connected to the high-voltage side, and the output end of the second conversion unit is connected to the input end of the second control module; the input end of the first conversion unit is connected to the low-voltage side, the output end of the first conversion unit is connected to the input end of the first control module, the controlled end of the first conversion unit is connected to the output end of the activation unit, and the signal input end of the activation unit is respectively connected to the control device, the power grid and the photovoltaic system; the second conversion unit outputs a second voltage according to the low-voltage side DC power to power the second control module; the activation unit operates under the control of the control device, and outputs an activation signal to the first conversion unit in response to the voltage input of the power grid or the photovoltaic system to conduct the power supply circuit between the low-voltage side and the first conversion unit, so that the first conversion unit outputs a first voltage according to the low-voltage side DC power to power the first control module.

[0013] In some embodiments, the first conversion unit includes a transformer component, a diode D1 and a switch tube M1; the positive input end of the transformer component is connected to the positive electrode of the low-voltage side, the negative input end of the transformer component is connected to the anode of the diode D1 and the source of the switch tube M1, the cathode of the diode D1 is connected to the drain of the switch tube M1 and the negative electrode of the low-voltage side, the gate of the switch tube M1 is connected to the output end of the activation unit, the positive output end of the transformer component is connected to the positive electrode of the input end of the first control module, and the negative output end of the transformer component is connected to the negative electrode of the input end of the second control module; the transformer component is used to convert the low-voltage side DC power into the first voltage.

[0014] In some embodiments, the second conversion unit includes a transformer T1, a diode D2, a capacitor C1, a first voltage component and a second voltage component; the primary winding of the transformer T1 is connected to the first voltage component, the first voltage component is connected to the low-voltage side, the first secondary winding of the transformer T1 is connected to the second voltage component, and the second voltage component is connected to the high-voltage side; the first end of the second secondary winding of the transformer T1 is connected to the anode of the diode D2, and the cathode of the diode D2 is connected to the first end of the capacitor C1 to output the second voltage; the second end of the capacitor C1 and the second end of the second secondary winding of the transformer T1 are grounded.

[0015] In order to solve the above technical problem, another technical solution adopted by the present invention is to provide a resonant converter, including the isolation control circuit as described above.

[0016] The beneficial effects of the embodiments of the present invention are as follows: different from the prior art, the embodiments of the present invention respectively set a control module on the low-voltage side and the high-voltage side of the transformer module to independently sample and drive the low-voltage side and the high-voltage side, thereby avoiding the use of an isolated driving chip and an isolated sampling chip, improving the reliability of the isolated control circuit and reducing the cost; in addition, by setting two transformer modules to respectively generate the power supply voltage of the control module to form an auxiliary power supply module, the construction of a flyback transformer is avoided, and the complexity of the auxiliary power supply module is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural diagram of an isolation control circuit in an existing LLC resonant converter;

[0018] Figure 2 It is a structural diagram of an auxiliary power supply module of an existing isolation control circuit;

[0019] Figure 3 This is a structural diagram of an isolation control circuit provided by an embodiment of the present utility model;

[0020] Figure 4 This is a structural diagram of an auxiliary power supply module provided by an embodiment of the present utility model;

[0021] Figure 5 This is a circuit schematic diagram of a second operational amplifier sampling unit provided by an embodiment of the present utility model;

[0022] Figure 6 This is a circuit schematic diagram of a first operational amplifier sampling unit provided in an embodiment of the present utility model. DETAILED DESCRIPTION

[0023] In order to facilitate the understanding of the present invention, the present invention is described in more detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it can be directly on the other element, or there can be one or more centered elements therebetween. When an element is described as "connected to" another element, it can be directly connected to the other element, or there can be one or more centered elements therebetween. The terms "vertical", "horizontal", "left", "right" and similar expressions used in this specification are for illustrative purposes only.

[0024] Unless otherwise defined, all technical and scientific terms used in this specification have the same meanings as those commonly understood by those skilled in the art to which this utility model belongs. The terms used in this specification and in the description of this utility model are only for the purpose of describing specific embodiments and are not intended to limit the utility model. The term "and / or" used in this specification includes any and all combinations of one or more of the relevant listed items.

[0025] Figure 1 The structure of an isolation control circuit for a conventional LLC resonant converter is shown. The low-voltage side 20 and high-voltage side 30 represent the low-voltage and high-voltage sides of the LLC resonant converter's transformer module, respectively. The isolation control circuit includes a second control unit 11, a second op amp sampling unit 12, a second Hall sampling unit 13, a current mutual sensing unit 14, a second drive unit 15, an isolation op amp sampling unit 16, a first Hall sampling unit 17, and an isolation drive unit 18.

[0026] The sampling signals obtained by the second op amp sampling unit 12, the second Hall sampling unit 13, and the current mutual inductance unit 14 on the high-voltage side 30 are directly sent to the second control unit 11, and the high-voltage side drive signal output by the second control unit 11 can also be directly sent to the second drive unit 15. However, the sampling signals obtained by the isolated op amp sampling unit 16 and the first Hall sampling unit 17 on the low-voltage side 20 need to be indirectly sent to the second control unit 11 through an isolation element, and the low-voltage side drive signal output by the second control unit 11 also needs to be indirectly sent to the second control unit 11 through an isolation element. Both the sampling signal and the drive signal need to be indirectly sent through the isolation element, which places high demands on the frequency and accuracy of the isolation element, and the isolation element is also expensive.

[0027] In order to solve the above problems, the present application provides an isolation control circuit, the structural diagram of which is shown in FIG. Figure 3 As shown, the isolation control circuit includes a first control module 100 and a second control module 200 .

[0028] The input end of the first control module 100 is connected to the sampling end of the low-voltage side 20 to obtain sampling data of the low-voltage side 20; the output end of the first control module 100 is connected to the driving end of the low-voltage side 20 to output a first driving signal to drive the low-voltage side 20.

[0029] The input end of the second control module 200 is connected to the sampling end of the high-voltage side 30 to obtain sampling data of the high-voltage side 30 , and the output end of the second control module 200 is connected to the driving end of the high-voltage side 30 to output a second driving signal to drive the high-voltage side 30 .

[0030] The low-voltage side 20 and the high-voltage side 30 are respectively the low-voltage side and the high-voltage side of the transformer module of the LLC resonant converter; the communication end of the first control module 100 is communicatively connected to the communication end of the second control module 200, and the second control module 200 and the first control module 100 exchange sampling data through the communication end.

[0031] Among them, the first control module 100 includes a first control unit 110, a first operational amplifier sampling unit 120, a first Hall sampling unit 130 and a first driving unit 140; the communication end of the first control unit 110 is communicatively connected to the communication end of the second control module 200, the first input end of the first control unit 110 is connected to the output end of the first operational amplifier sampling unit 120, the second input end of the first control unit 110 is connected to the output end of the first Hall sampling unit 130, and the output end of the first control unit 110 is connected to the input end of the first driving unit 140.

[0032] The input end of the first operational amplifier sampling unit 120 is connected to the first sampling end of the low-voltage side 20 , the input end of the first Hall sampling unit 130 is connected to the second sampling end of the low-voltage side 20 , and the output end of the first driving unit 140 is connected to the driving end of the low-voltage side 20 .

[0033] The first operational amplifier sampling unit 120 is used to obtain voltage sampling data of the low-voltage side 20, the first Hall sampling unit 130 is used to obtain current sampling data of the low-voltage side 20, the first control unit 110 is used to output a first control signal, and the first driving unit 140 is used to output a first driving signal to the low-voltage side 20 according to the first control signal.

[0034] The second control module 200 includes a second control unit 210, a second operational amplifier sampling unit 220, a second Hall sampling unit 230, a current mutual induction unit 240 and a second driving unit 250; the communication end of the second control unit 210 is communicatively connected to the communication end of the first control module 100, the first input end of the second control unit 210 is connected to the output end of the second operational amplifier sampling unit 220, the second input end of the second control unit 210 is connected to the output end of the second Hall sampling unit 230, the third input end of the second control unit 210 is connected to the output end of the current mutual induction unit 240, and the output end of the second control unit 210 is connected to the input end of the second driving unit 250.

[0035] The input end of the second operational amplifier sampling unit 220 is connected to the first sampling end of the high-voltage side 30, the input end of the second Hall sampling unit 230 is connected to the second sampling end of the high-voltage side 30, the input end of the current mutual induction unit 240 is connected to the third sampling end of the high-voltage side 30, and the output end of the second driving unit is connected to the driving end of the high-voltage side 30.

[0036] The second operational amplifier sampling unit 220 is used to obtain voltage sampling data of the high-voltage side 30, the second Hall sampling unit 230 and the current mutual inductance unit 240 are used to obtain current sampling data of the high-voltage side 30, the second control unit 210 is used to output a second control signal, and the second driving unit 250 is used to output a second driving signal to the high-voltage side 30 according to the second control signal.

[0037] In some embodiments, the first control unit 110 includes a controller, such as a single-chip microcomputer used by a panel in an energy storage system to implement functions such as control and sampling of DC / AC input and output and display screen control. This single-chip microcomputer is used to act as the first control unit 110 to avoid increasing the number of single-chip microcomputers used and increasing costs.

[0038] In some embodiments, the second control unit 210 includes a controller and an isolation communication chip; the first communication end of the isolation communication chip is connected to the communication end of the first control module 110, the second communication end of the isolation communication chip is connected to the communication end of the controller, the first input end of the controller is connected to the output end of the second op amp sampling unit 220, the second input end of the controller is connected to the output end of the second Hall sampling unit 230, the third input end of the controller is connected to the output end of the current mutual induction unit 240, and the output end of the controller is connected to the input end of the second drive unit 250.

[0039] As an example but not limitation, the isolated communication chip is a 485 / CAN isolated communication chip.

[0040] Different from the prior art, the embodiment of the present invention sets a control module on the low-voltage side and the high-voltage side of the transformer module respectively to independently sample and drive the low-voltage side and the high-voltage side respectively, thereby avoiding the use of an isolation drive chip and an isolation sampling chip, improving the reliability of the isolation control circuit and reducing the cost.

[0041] Figure 2 for Figure 1 The auxiliary power supply module of the isolation control circuit is shown as a schematic diagram. The auxiliary power supply module is used to Figure 1 The illustrated isolation control circuit provides power. The auxiliary power module includes transformer T1, transformer T2, a first control circuit 31, a second control circuit 32, and a rectifier circuit 33, forming a flyback switching power supply. BAT / PV and AC_L / N are used to activate the flyback switching power supply. However, flyback switching power supplies have complex circuitry, and debugging the BAT / PV / AC auxiliary source activation circuit is time-consuming. Faults are prone to occur and difficult to troubleshoot, and flyback switching power supplies occupy a significant amount of PCBA area.

[0042] To solve this problem, the present application proposes an auxiliary power supply module, the structural diagram of which is shown in FIG. Figure 4As shown, the auxiliary power supply module includes a first conversion unit 310 , a second conversion unit 320 and an activation unit 330 .

[0043] The first input end of the second conversion unit 320 is connected to the low-voltage side 20, the second input end of the second conversion unit 320 is connected to the high-voltage side 30, and the output end of the second conversion unit 320 is connected to the input end of the second control module 200; the input end of the first conversion unit 310 is connected to the low-voltage side 20, the output end of the first conversion unit 310 is connected to the input end of the first control module 100, the controlled end of the first conversion unit 310 is connected to the output end of the activation unit 330, and the signal input end of the activation unit 330 is respectively connected to the control device, the power grid and the photovoltaic system.

[0044] The power input end of the second conversion unit 320 outputs a second voltage according to the low-voltage side DC power to power the second control module 200; the activation unit 330 operates under the control of the switching signal output by the control device, and responds to the voltage input of the power grid or the photovoltaic system to output an activation signal to the first conversion unit 310 to connect the power supply circuit between the low-voltage side and the first conversion unit 310, so that the first conversion unit 310 outputs a first voltage according to the low-voltage side DC power to power the first control module 110.

[0045] Specifically, the first conversion unit 310 includes a voltage transformation component 311 , a diode D1 and a switch tube M1 , and the second conversion unit 320 includes a transformer T1 , a diode D2 , a capacitor C1 , a first voltage component 321 and a second voltage component 322 .

[0046] The positive input terminal of the transformer component 311 is connected to the positive electrode BAT+ on the low-voltage side, the negative input terminal of the transformer component 311 is connected to the anode of the diode D1 and the source of the switch tube M1, the cathode of the diode D1 is connected to the drain of the switch tube M1 and the negative electrode BAT- on the low-voltage side, the gate of the switch tube M1 is connected to the output terminal of the activation unit 330, the positive output terminal of the transformer component 311 is connected to the positive electrode 12V+ of the input terminal of the first control module, and the negative output terminal of the transformer component 311 is connected to the negative electrode 12V+ of the input terminal of the second control module; the transformer component 311 is used to convert the low-voltage side direct current into a first voltage.

[0047] The primary winding of the transformer T1 is connected to the first voltage component 321, the first voltage component 321 is connected to the low-voltage side, the first secondary winding of the transformer T1 is connected to the second voltage component 322, and the second voltage component 322 is connected to the high-voltage side; the first end of the second secondary winding of the transformer T1 is connected to the anode of the diode D2, and the cathode of the diode D2 is connected to the first end of the capacitor C1 to output a second voltage; the second end of the capacitor C1 and the second end of the second secondary winding of the transformer T1 are grounded.

[0048] Among them, BAT+ / BAT- is the low-voltage side DC power, BUS+ / BUS- is the high-voltage side DC power (bus voltage), 12V+ / 12V- is generated by stepping down the low-voltage side DC power and is used to power the first control module; +15V / GND is the voltage generated after the first control module controls the low-voltage side inverter circuit to work, which is used to power the second control module. In the actual circuit, +15V and BUS voltage share the same ground; PV / AC are the photovoltaic input voltage and the grid input voltage, respectively. When the PV voltage or the grid voltage is connected, the low-voltage side power supply voltage is activated by the activation circuit.

[0049] As an example and not a limitation, the present application embodiment provides a circuit principle of a second operational amplifier sampling unit, such as Figure 5 As shown, the second operational amplifier sampling unit includes a resistor R1, a resistor R5, a resistor R9, a resistor R13, a resistor R17, a capacitor C1, a capacitor C5, a capacitor C6, a capacitor C10, a capacitor C11, a capacitor C12 and an operational amplifier U1A.

[0050] Specifically, the first end of the capacitor C10 is connected to the positive electrode of the first sampling terminal I_PV in+ on the high-voltage side and the first end of the resistor R13, the first end of the capacitor C11 is connected to the negative electrode of the first sampling terminal I_PV in- on the high-voltage side and the first end of the resistor R5, and the second end of the capacitor C10 and the second end of the capacitor C11 are grounded AGND; the second end of the resistor R13 is connected to the non-inverting input terminal of the operational amplifier U1A, the first end of the resistor R17 and the first end of the capacitor C12, the second end of the resistor R17 and the second end of the capacitor C12 are connected to the low-voltage power supply terminal +0.5V; the second end of the resistor R5 is connected to the inverting input terminal of the operational amplifier U1A, the first end of the resistor R1 and the first end of the capacitor C1.

[0051] The second end of the resistor R1 is connected to the second end of the capacitor C1, the output end of the operational amplifier U1A, and the first end of the resistor R9. The positive electrode of the power input end of the operational amplifier U1A is connected to the high-voltage power supply end 5V_L and the first end of the capacitor C5. The second end of the capacitor C5 and the negative electrode of the power input end of the operational amplifier U1A are grounded AGND. The second end of the resistor R9 is connected to the first end of the capacitor C6 and the first input end I_PV in of the second control unit. The second end of the capacitor C6 is grounded AGND.

[0052] Different from the prior art, the embodiment of the present invention avoids the construction of a flyback transformer and reduces the complexity of the auxiliary power module by setting up two transformer modules to generate the supply voltage of the control module respectively to form an auxiliary power module.

[0053] As an example and not a limitation, the present application embodiment provides a circuit principle of a first operational amplifier sampling unit, such as Figure 6As shown, the first operational amplifier sampling unit includes resistor R139, resistor R140, resistor R141, resistor R142, resistor R143, resistor R144, resistor R145, resistor R146, capacitor C104, capacitor C105, capacitor C106, capacitor C107, capacitor C108, capacitor C109, capacitor C110, capacitor C111, operational amplifier U16A and isolation amplifier U15.

[0054] The first end of the resistor R140 is connected to the positive electrode V+ of the first sampling terminal on the low voltage side, the second end of the resistor R140 is connected to the first end of the resistor R144, the first end of the capacitor C108, the first end of the capacitor C110 and the input terminal IN of the isolation amplifier U15; the first end of the resistor R146 is connected to the negative electrode V- of the first sampling terminal on the low voltage side, the second end of the resistor R146 is connected to the second end of the resistor R144, the second end of the capacitor C108, the second end of the capacitor C109, the second end of the capacitor C110 and the control terminal SHTDN and the ground terminal G of the isolation amplifier U15. ND1 is connected to ground - VINS2; the first end of the capacitor C109 and the input end VDD1 of the isolation amplifier U15 are connected to the power supply end +5V.SAM, the input end VDD2 of the isolation amplifier U15 and the first end of the capacitor C106 are connected to the power supply end +5V, the positive output end OUTP of the isolation amplifier U15 is connected to the first end of the capacitor C107 and the first end of the resistor R141, the negative output end OUTN of the isolation amplifier U15 is connected to the second end of the capacitor C107 and the first end of the resistor R143, and the ground end GND2 of the isolation amplifier U15 is connected to the ground GND.

[0055] The second end of capacitor C106, the first end of resistor R139, and the first end of capacitor C104 are connected to ground GND, the second end of capacitor C104 is connected to the second end of resistor R139, the second end of resistor R141, and the non-inverting input terminal of operational amplifier U16A, the second end of resistor R143 is connected to the inverting input terminal of operational amplifier U16A, the second end of capacitor C143, the first end of resistor R145, and the first end of capacitor C111; the positive pole of the power input terminal of operational amplifier U16A and capacitor C105 are connected to the power supply terminal +12V, the second end of capacitor C105 is grounded GND, and the negative pole of the power input terminal of operational amplifier U16A is grounded GND; the output terminal of operational amplifier U16A is connected to the first end of resistor R142, the second end of resistor R142 is connected to the second end of resistor R145, the second end of capacitor C111, and the first input terminal V.PCBA of the first control unit.

[0056] It should be noted that the preferred embodiments of the present invention are given in the specification and drawings of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described in this specification. These embodiments do not serve as additional limitations on the content of the present invention. The purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive. In addition, the above-mentioned technical features continue to be combined with each other to form various embodiments not listed above, which are all considered to be within the scope of the description of the present invention; further, it is obvious to those skilled in the art that improvements or changes can be made based on the above description, and all such improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. An isolation control circuit, characterized in that: include: a first control module and a second control module; The input end of the first control module is connected to the sampling end of the low-voltage side to obtain the sampling data of the low-voltage side; The input end of the second control module is connected to the sampling end of the high-voltage side to obtain sampling data of the high-voltage side, wherein the low-voltage side and the high-voltage side are respectively the low-voltage side and the high-voltage side of the transformer module; The communication end of the first control module is communicatively connected to the communication end of the second control module, and the second control module and the first control module exchange sampling data via the communication end.

2. The circuit according to claim 1, wherein: The output end of the first control module is connected to the driving end of the low-voltage side to output a first driving signal to drive the low-voltage side; The output end of the second control module is connected to the driving end of the high-voltage side to output a second driving signal to drive the high-voltage side.

3. The circuit according to claim 1, wherein: Also includes: an auxiliary power supply module for supplying power to the first control module and the second control module; The first input end of the auxiliary power supply module is connected to the low-voltage side, the second input end of the auxiliary power supply module is connected to the high-voltage side, the first output end of the auxiliary power supply module is connected to the input end of the first control module, the second output end of the auxiliary power supply module is connected to the input end of the second control module, and the signal input end of the auxiliary power supply module is respectively connected to the control device, the power grid and the photovoltaic system.

4. The circuit according to claim 2, characterized in that The first control module includes a first control unit, a first operational amplifier sampling unit, a first Hall sampling unit and a first driving unit; The communication terminal of the first control unit is communicatively connected to the communication terminal of the second control module, the first input terminal of the first control unit is connected to the output terminal of the first operational amplifier sampling unit, the second input terminal of the first control unit is connected to the output terminal of the first Hall sampling unit, and the output terminal of the first control unit is connected to the input terminal of the first driving unit; The input end of the first operational amplifier sampling unit is connected to the first sampling end of the low-voltage side, the input end of the first Hall sampling unit is connected to the second sampling end of the low-voltage side, and the output end of the first driving unit is connected to the driving end of the low-voltage side; The first operational amplifier sampling unit is used to obtain voltage sampling data of the low-voltage side, the first Hall sampling unit is used to obtain current sampling data of the low-voltage side, the first control unit is used to output a first control signal, and the first driving unit is used to output the first driving signal to the low-voltage side according to the first control signal.

5. The circuit according to claim 2, characterized in that The second control module includes a second control unit, a second operational amplifier sampling unit, a second Hall sampling unit, a current mutual induction unit and a second driving unit; The communication terminal of the second control unit is communicatively connected to the communication terminal of the first control module, the first input terminal of the second control unit is connected to the output terminal of the second operational amplifier sampling unit, the second input terminal of the second control unit is connected to the output terminal of the second Hall sampling unit, the third input terminal of the second control unit is connected to the output terminal of the current mutual induction unit, and the output terminal of the second control unit is connected to the input terminal of the second driving unit; The input end of the second operational amplifier sampling unit is connected to the first sampling end of the high-voltage side, the input end of the second Hall sampling unit is connected to the second sampling end of the high-voltage side, the input end of the current mutual induction unit is connected to the third sampling end of the high-voltage side, and the output end of the second driving unit is connected to the driving end of the high-voltage side; The second operational amplifier sampling unit is used to obtain voltage sampling data on the high-voltage side, the second Hall sampling unit and the current mutual inductance unit are used to obtain current sampling data on the high-voltage side, the second control unit is used to output a second control signal, and the second drive unit is used to output the second drive signal to the high-voltage side according to the second control signal.

6. The circuit according to claim 5, characterized in that The second control unit includes a controller and an isolation communication chip; The first communication terminal of the isolation communication chip is connected to the communication terminal of the first control module, the second communication terminal of the isolation communication chip is connected to the communication terminal of the controller, the first input terminal of the controller is connected to the output terminal of the second operational amplifier sampling unit, the second input terminal of the controller is connected to the output terminal of the second Hall sampling unit, the third input terminal of the controller is connected to the output terminal of the current mutual induction unit, and the output terminal of the controller is connected to the input terminal of the second driving unit.

7. The circuit according to claim 3, characterized in that The auxiliary power supply module includes a first conversion unit, a second conversion unit and an activation unit; The first input end of the second conversion unit is connected to the low-voltage side, the second input end of the second conversion unit is connected to the high-voltage side, and the output end of the second conversion unit is connected to the input end of the second control module; The input end of the first conversion unit is connected to the low-voltage side, the output end of the first conversion unit is connected to the input end of the first control module, the controlled end of the first conversion unit is connected to the output end of the activation unit, and the signal input end of the activation unit is connected to the control device, the power grid and the photovoltaic system respectively; The second conversion unit outputs a second voltage based on the low-voltage side DC power to power the second control module; the activation unit operates under the control of the control device, and outputs an activation signal to the first conversion unit in response to the voltage input of the power grid or the photovoltaic system to connect the power supply circuit between the low-voltage side and the first conversion unit, so that the first conversion unit outputs a first voltage based on the low-voltage side DC power to power the first control module.

8. The circuit according to claim 7, characterized in that The first conversion unit includes a voltage transformation component, a diode D1 and a switch tube M1; The positive input terminal of the transformer component is connected to the positive electrode of the low-voltage side, the negative input terminal of the transformer component is connected to the anode of the diode D1 and the source of the switch tube M1, the cathode of the diode D1 is connected to the drain of the switch tube M1 and the negative electrode of the low-voltage side, the gate of the switch tube M1 is connected to the output terminal of the activation unit, the positive output terminal of the transformer component is connected to the positive electrode of the input terminal of the first control module, and the negative output terminal of the transformer component is connected to the negative electrode of the input terminal of the second control module; The transformer component is used to convert the low-voltage side direct current into the first voltage.

9. The circuit according to claim 7, characterized in that The second conversion unit includes a transformer T1, a diode D2, a capacitor C1, a first voltage component and a second voltage component; The primary winding of the transformer T1 is connected to the first voltage component, the first voltage component is connected to the low-voltage side, the first secondary winding of the transformer T1 is connected to the second voltage component, and the second voltage component is connected to the high-voltage side; The first end of the second secondary winding of the transformer T1 is connected to the anode of the diode D2, and the cathode of the diode D2 is connected to the first end of the capacitor C1 to output the second voltage; the second end of the capacitor C1 and the second end of the second secondary winding of the transformer T1 are grounded.

10. A resonant converter, characterized in that: include: The isolation control circuit according to any one of claims 1 to 9.

Images