Energy management circuit with dual energy sources alternately conducting

Abstract

The application discloses a dual-energy-source alternate conduction energy management circuit, and relates to the fields of energy harvesting and circuit design.The dual-energy-source alternate conduction energy management circuit has a first input end, a second input end and an output end, and comprises a selection module, a control module, a first switch tube and a second switch tube.The input end of the control module is connected with the selection module, the output end of the control module is connected with the gate of the first switch tube and the gate of the second switch tube respectively, the source of the first switch tube is connected with the first input end of the energy management circuit, the drain of the first switch tube is connected with the output end of the energy management circuit through a diode, the source of the second switch tube is connected with the second input end of the energy management circuit, and the drain of the second switch tube is connected with the output end of the energy management circuit through a diode.The application can realize dual-energy-source alternate conduction power supply, avoid the coupling influence of simultaneous operation, reduce energy transmission loss and improve energy harvesting efficiency.

Description

Technical Field

[0001] This invention relates to the fields of energy harvesting and circuit design, and in particular to an energy management circuit with alternating conduction of two energy sources. Background Technology

[0002] With the widespread application of distributed electronic devices in IoT monitoring, environmental data acquisition, and other fields, achieving self-sufficiency using environmental energy sources such as solar, wind, and vibration energy has become an important development direction. Environmental energy is intermittent and fluctuates; a single energy source may fail to provide a stable power supply continuously under conditions of insufficient sunlight, weak wind, or lack of vibration, thus affecting the system's continuous operation. To improve the stability and reliability of power supply, existing technologies are increasingly adopting dual-energy-source power supply structures. Current dual-energy-source solutions mostly employ parallel connection or simple switching methods. In actual operation, the two energy sources may interfere with each other, resulting in reverse current generation, uneven power distribution, and additional energy losses, thereby reducing overall energy utilization efficiency. Summary of the Invention

[0003] This invention provides an energy management circuit with alternating conduction of dual energy sources to reduce energy transmission loss and improve energy harvesting efficiency.

[0004] To solve the above-mentioned technical problems, the present invention provides the following technical solution: A dual-energy-source alternating conduction energy management circuit has a first input terminal, a second input terminal, and an output terminal. The energy management circuit includes a selection module, a control module, a first switching transistor, and a second switching transistor, wherein: The input terminal of the control module is connected to the selection module, and the output terminal of the control module is connected to the gate of the first switching transistor and the gate of the second switching transistor, respectively. The source of the first switching transistor is connected to the first input terminal of the energy management circuit, which is used to connect to the first energy storage capacitor of the first energy harvesting device. The drain of the first switching transistor is connected to the output terminal of the energy management circuit via a diode. The source of the second switching transistor is connected to the second input terminal of the energy management circuit, which is used to connect to the second energy storage capacitor of the second energy harvesting device. The drain of the second switching transistor is connected to the output terminal of the energy management circuit via a diode. The output terminal of the energy management circuit is used to supply power to the load via a voltage converter.

[0005] Compared with the prior art, the present invention has at least the following beneficial effects: The energy management circuit of this invention, which features alternating conduction of dual energy sources, enables power supply from both sources, avoiding coupling effects between the two power supply branches and reducing energy losses during transmission. Furthermore, by employing different conduction strategies based on the charging characteristics of the supercapacitor, the overall energy harvesting efficiency of the system is effectively improved. In addition, if a component in a single branch fails, the detection module can quickly switch to the other branch and maintain continuous conduction, ensuring stable power supply to the load. Attached Figure Description

[0006] The accompanying drawings in this application are intended to supplement the textual description in the specification with graphics, and to further explain the technical solution of this application. They do not constitute an undue limitation on this application.

[0007] Figure 1 This is a schematic diagram illustrating the application of the energy management circuit with alternating conduction of dual energy sources according to the present invention; Figure 2 This is a schematic diagram of the energy management circuit of the present invention, which features alternating conduction of dual energy sources. Figure 3 This is a circuit schematic diagram of the reference voltage module in this invention; Figure 4a The circuit schematic diagram of the selected module in this invention is shown below. Figure 4b This is a circuit schematic diagram of the control module in this invention; Figure 4c This is a circuit diagram of the detection module in this invention; Figure 5 This is a simulation result diagram of the alternating conduction of the present invention; Figure 6a This is a simulation result diagram of the high-voltage conduction mode of the present invention; Figure 6b This is a simulation result diagram of the low-voltage conduction mode of the present invention; Figure 7a This is a simulation result diagram of high-voltage branch fault switching according to the present invention; Figure 7b The figure shows the simulation results of low-voltage branch fault switching according to the present invention.

[0008] Figure label: 10. Selection module; 20. Control module; 30. Detection module; 40. Voltage converter. Detailed Implementation

[0009] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0010] In the description of this invention, it should be understood that the terms "center," "lateral," "longitudinal," "front," "rear," "left," "right," "upper," "lower," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0011] This invention is an energy management circuit with alternating dual energy sources for energy harvesting systems such as solar, wind, and vibration energy. Energy harvested by the energy harvesting device is stored in a supercapacitor and used as the circuit's energy source input. A voltage converter then generates a stable voltage to continuously power the load.

[0012] This invention provides an energy management circuit 100 with alternating conduction of dual energy sources, such as... Figure 1-2 As shown, it has a first input terminal. V C1 Second input terminal V C2 and output terminal V o The energy management circuit 100 includes a selection module 10, a control module 20, and a first switching transistor. S 1 and second switching transistors S 2, of which: The input terminal of the control module 20 is connected to the selection module 10, and the output terminal of the control module 20 is connected to the first switching transistor. S 1's gate and second switch S 2 gates; First switching transistor S The source of 1 is connected to the first input terminal of the power management circuit 100. V C1 (Used to acquire the voltage signal of the first energy source), this first input terminal V C1 The first energy storage capacitor used to connect the first energy harvesting device (i.e., energy harvesting device I) C 1. First switching transistor S The drain of 1 is connected to a diode. D a1 Connect to the output terminal of the energy management circuit 100 V o ; Second switching transistor S The source of 2 is connected to the second input terminal of the power management circuit 100. V C2 (Used to acquire the voltage signal of the second energy source), this second input terminal VC2 The second energy storage capacitor is used to connect the second energy harvesting device (i.e., energy harvesting device II). C 2. Second switching transistor S The drain of 2 is connected to a diode. D a2 Connect to the output terminal of the energy management circuit 100 V o The output terminal of the energy management circuit 100 V o For use as a load via voltage converter 40 (specifically, a DC-DC converter) Figure 1 The middle part is shown as R L Power supply. In specific implementation, the first switching transistor... S 1 and second switching transistors S Both can be P-type MOSFETs.

[0013] Figure 1 This is a schematic diagram illustrating the application of the dual-energy-source alternating conduction energy management circuit 100 of the present invention, which is also a general framework diagram of the dual-energy-harvesting system. The dual-energy-source alternating conduction energy management circuit 100 of the present invention mainly includes a selection module 10 and a control module 20. The first energy source and the second energy source are respectively derived from the energy storage capacitor of the energy harvesting device I. C 1 and the energy storage capacitor of energy harvesting device II C 2. By controlling the two PMOS switching transistors S 1 and S The alternating conduction function and conduction strategy of the circuit are achieved by using the conduction state of 2. Two diodes are placed between the source of the PMOS switch and the voltage converter 40. D a1 and D a2 This is to avoid the voltage coupling effect when the branch is turned on, and to ensure that each sub-module of the circuit works normally.

[0014] In some embodiments of the present invention, such as Figure 2 and Figure 4a As shown, the selection module 10 includes a first operational amplifier. U Operational amplifiers 1 to 4 U 4. First MOSFET Q MOSFETs 1 to 8 Q 8, of which: The first input terminal of the energy management circuit 100 V C1 Passing through the first resistor in sequence R 1 and second resistors R 2. Grounding achieves voltage division; the second input terminal of the energy management circuit 100 V C2 Passing through the fourth resistor in sequenceR 4 and the third resistor R 3. Grounding achieves voltage division; First operational amplifier U The inverting input of 1 and the second operational amplifier U The non-inverting input terminals of 2 are all connected to the first resistor. R 1 and second resistors R The connection point between 2, the first operational amplifier U The non-inverting input of 1 and the third operational amplifier U The non-inverting input terminals of all three are connected to the first reference voltage. V ref1 ; Second operational amplifier U The inverting input of 2 and the fourth operational amplifier U The inverting input terminals of 4 are all connected to a second reference voltage. V ref2 Third operational amplifier U The inverting input of 3 and the fourth operational amplifier U The non-inverting input of 4 is connected to a fourth resistor. R 4 and the third resistor R The connection point between 3; First operational amplifier U Operational amplifiers 1 to 4 U The outputs of all four terminals are connected to the intermediate control node. V a intermediate control node V a Through the fifth resistor R 5 can be connected to a high-level VCC, or it can be connected to a load terminal to achieve a passive circuit.

[0015] Furthermore, the first MOSFET Q The gate of 1 is connected to the intermediate control node. V a The drain path passes through the sixth resistor. R 6. Connect the first input terminal of the energy management circuit 100 V C1 The other path is simultaneously connected to the second MOSFET. Q 2's gate and the fifth MOS transistor Q 5's gate, the first MOS transistor Q The source of 1 is grounded; Second MOSFET Q The drain of 2 passes through the seventh resistor. R 7. Connect the first input terminal of the energy management circuit 100 V C1 The other path connects to the sixth MOSFET. Q Gate of 6, second MOSFETQ The source of 2 is grounded; Third MOSFET Q The gate of 3 is connected to the intermediate control node. V a The drain path passes through the eighth resistor. R 8 connects to the second input terminal of the energy management circuit 100 V C2 The other path is simultaneously connected to the fourth MOSFET. Q Gate of 4 and the eighth MOS transistor Q 8 gate, third MOSFET Q The source of 3 is grounded; Fourth MOSFET Q The drain of 4 passes through the ninth resistor. R 9 connects to the second input terminal of the energy management circuit 100 V C2 The other path connects to the seventh MOSFET. Q Gate of 7, fourth MOSFET Q 4's source is grounded; Fifth MOSFET Q 5's source and the sixth MOSFET Q The sources of 6 are all connected to the first input terminal of the power management circuit 100. V C1 The seventh MOSFET Q The source of 7 and the eighth MOS transistor Q The sources of 8 are all connected to the second input terminal of the power management circuit 100. V C2 Fifth MOSFET Q 5's drain and the seventh MOSFET Q The drains of all 7 are connected to the first intermediate output node. V 1. Sixth MOSFET Q The drain of 6 and the eighth MOSFET Q The drains of all 8 are connected to the second intermediate output node. V 2.

[0016] Furthermore, to prevent mutual interference between signals and improve the stability of the circuit, diodes can be installed in the control branch, i.e., intermediate control nodes. V a With the first operational amplifier U Operational amplifiers 1 to 4 U The first diode is connected between the output terminals of 4. D Diodes 1 to 4 D 4; Fifth MOSFET Q 5's drain and the seventh MOSFET Q 7's drain and the first intermediate output nodeV A fifth diode is connected between each of the 1s. D Diodes 5 and 7 D 7. Sixth MOSFET Q The drain of 6 and the eighth MOSFET Q 8 drain and second intermediate output node V A sixth diode is connected between points 2 and 3 respectively. D Diodes 6 and 8 D 8. In specific implementation, the first MOSFET Q 1 to 4 MOSFETs Q 4 can all be N-type MOSFETs, the fifth MOSFET Q 5 to 8 MOSFETs Q All 8 can be P-type MOSFETs.

[0017] Figure 2 This is a schematic diagram of the overall principle of the dual-energy-source alternating conduction energy management circuit 100 of the present invention, which specifically illustrates the wiring methods between the components and branches. The voltage signals of the first and second energy sources are compared with the first and second reference voltages set in the selection module 10, respectively. Based on the output logic of the four comparators, the control module 20 implements different alternating conduction schemes. Specifically, the voltage signals after voltage division of the two branches are... and With two reference voltages V ref1 and V ref2 The comparison is made between the voltage signals. and The following relationship must be satisfied: ; ; Preferably, the first resistor R 1 and second resistors R The ratio of 2 to the fourth resistor R 4 and the third resistor R The ratio of 3 is the same, and the energy storage capacitor C 1 and C 2 are capacitors of the same specification, first reference voltage V ref1 The voltage corresponding to the maximum energy storage power of each energy storage capacitor V m The following relationship must be satisfied: ; Second reference voltage V ref2This is the minimum operating voltage of the voltage converter 40. During charging of the energy storage capacitor, the current decreases continuously as the voltage increases, indicating a maximum energy storage power point. When the energy storage capacitor voltage is less than the voltage corresponding to the maximum energy storage power, the higher the voltage, the greater the energy storage power; conversely, when the energy storage capacitor voltage is greater than the voltage corresponding to the maximum energy storage power, the higher the voltage, the smaller the energy storage power. Therefore, when the voltage signal after voltage division from the two energy sources is greater than... V ref1 When the voltage is high, the branch should conduct, thus making Figure 1 The entire energy harvesting system shown can achieve greater energy efficiency; conversely, when the voltage signals after voltage division of the two energy sources are both less than... V ref1 The low-voltage branch should be turned on at this time. Furthermore, the voltage converter 40 has a minimum operating voltage. V ref2 A special case should also be considered: the voltage signal after voltage division by a storage capacitor is less than... V ref1 And the signal after voltage division by the other energy storage capacitor is less than V ref2 If neither branch is conducting, the energy stored in a single capacitor will be wasted. In this case, the branch with the higher voltage should be conducting.

[0018] Figure 4a The circuit schematic for module 10 in this invention demonstrates the selection of different conduction strategies based on the two energy sources. Operational amplifier. U 1. Used to compare the voltage signals after voltage division from the first energy source. and V ref1 ,in V ref1 Connect to the non-inverting input terminal. Connect to the inverting input terminal. hour, U 1. Output low level; hour, U 1. Output high level. Operational amplifier. U 2 is used for comparison and V ref2 ,in Connect to the non-inverting input terminal. V ref2 Connect to the inverting input terminal. hour, U 2. Output high level; hour, U 2. Output low level. Operational amplifier. U 3. Used to compare the voltage signal after voltage division from the second energy source. and V ref1 ,in Vref1 Connect to the non-inverting input terminal. Connect to the inverting input terminal. hour, U 3. Output low level; hour, U 3. Output high level. Operational amplifier. U 4. Used for comparison and V ref2 ,in Connect to the non-inverting input terminal. V ref2 Connect to the inverting input terminal. hour, U 4. Output high level; hour, U 4. Output high level.

[0019] operational amplifier U 1~ U The output terminals of 4 are connected to diodes respectively. D 1~ D 4 cathode, diode D 1~ D After the anodes of 4 are connected in parallel, they are connected through a pull-up resistor. R 5 is connected to the high level VCC, thus enabling intermediate control nodes. V a This forms an AND gate logic function. Specifically, it occurs if and only if... U 1~ U When all outputs of 4 are high, V a It is pulled high; in other cases, V a All are low level. That is, only when and under conditions V a Output a high-level signal, otherwise V a All outputs are low level.

[0020] when V a When it is high level, Q 1 and Q 3 is on, and Q 2 and Q 4. Turn off, making the PMOS transistor Q 5 and Q The gate of 8 is at zero potential. Q 6 and Q The gates of 7 are respectively through R 7 and R 9. Pull up to VC1 and V C2 .at this time, Q 5 and Q 8 conduction, Q 6 and Q 7. Turn off V C2 via node V 2. Connect to a subtractor (i.e., an operational amplifier) U 5. Related circuits) Non-inverting input terminal, V C1 via node V 1. Connect to the inverting input of the subtractor. Conversely, when... V a When it is low level, Q 2 and Q 4 is on, and Q 1 and Q 3. Turn off, making Q 6 and Q 7 conduction, Q 5 and Q 8. Turn off V C1 via node V 2. Connect to a subtractor (i.e., an operational amplifier) U 5. Related circuits) Non-inverting input terminal, V C2 via node V 1. Connect to the inverting input of the subtractor.

[0021] In some embodiments of the present invention, such as Figure 2 and Figure 4b As shown, the control module 20 includes a fifth operational amplifier. U 5. Sixth Operational Amplifier U 6. Ninth MOSFET Q 9 to 11 MOSFETs Q 11 ,in: Fifth operational amplifier U The inverting input of 5 goes through the tenth resistor. R 10 Connect the first intermediate output node V 1. Another path is through the eleventh resistor. R 11 Connect the fifth operational amplifier U The output of 5, the fifth operational amplifier U The non-inverting input of 5 is connected to the twelfth resistor. R 12 Connect the second intermediate output node V 2. Another path is through the thirteenth resistor. R 13Ground, fifth operational amplifier U The output of 5 is connected to the sixth operational amplifier. U The inverting input of 6; Sixth operational amplifier U The non-inverting input of 6 passes through the fourteenth resistor. R 14 Grounded, the other path goes through the fifteenth resistor. R 15 Connect the sixth operational amplifier U The output of 6, the sixth operational amplifier U The output terminal of 6 is connected to the ninth MOSFET. Q Gate of 9 and 10th MOSFET Q 10 The gate; Ninth MOSFET Q The drain of 9 passes through the sixteenth resistor. R 16 Connect the first input terminal of the energy management circuit 100 V C1 The other path is connected to the eleventh MOSFET. Q 11 The gate of the ninth MOS transistor Q 9's source is grounded; 10th MOSFET Q 10 The drain path passes through the eighteenth resistor. R 18 Connect the second input terminal of the energy management circuit 100 V C2 The other path is connected to the second switching transistor. S Gate 2, the tenth MOSFET Q 10 The source is grounded; Eleventh MOSFET Q 11 The drain path passes through the seventeenth resistor. R 17 Connect the first input terminal of the energy management circuit 100 V C1 The other path is connected to the first switching transistor. S Gate of 1, 11th MOSFET Q 11 The source is grounded. In specific implementation, the ninth MOSFET... Q 9 to 11 MOSFETs Q 11 Both can be N-type MOSFETs.

[0022] Figure 4bThis is a circuit diagram of the control module 20 in this invention. The input voltages of the two energy sources are subtracted, and the results are compared with a hysteresis condition to control the switching transistor. S 1 and S 2. Switching state. When the first energy source passes through the second intermediate output node. V 2. Operational amplifier U 5. Non-inverting input terminal, the second energy source is connected to the first intermediate output node. V 1. Connect to operational amplifier U When the inverting input is 5, the PMOS switch controlling the high-voltage branch is turned on; when the second energy source passes through the second intermediate output node... V 2. Operational amplifier U 5. Non-inverting input terminals, the first energy source outputs through the first intermediate output node. V 1. Connect to operational amplifier U When the inverting input is 5, the PMOS switch of the low-voltage branch is turned on.

[0023] Specifically, operational amplifier U 5 and R 10 ~ R 13 Construct a subtractor circuit, U 5's output voltage V b Determined by the following formula: ; in, V + , V - operational amplifiers U The non-inverting and inverting input voltages of 5; Preferably, the present invention selects Therefore, the above formula can be further simplified to: ; operational amplifier U 6 and R 14 , R 15 Together they form a hysteresis comparator circuit, based on the subtractor (i.e., operational amplifier). U 5. Related circuits) Output V b Output high level backward V OH or low level V OL The hysteresis comparator has an upper threshold voltage. V T+ and lower threshold voltage V T-The calculation formula is as follows: ; ; In the energy management circuit 100, the control envelope is controlled by an NMOS transistor. Q 9~ Q 13 With pull-up resistor R 16 ~ R 18 Together constitute Q 11 and Q 12 Common control switch S 1; Q 10 and Q 13 Common control switch S 2. Among them, Q 10 Depend on U 6 Output Signals V d Direct control, Q 11 Depend on Q 9 and R 16 The generated V d Inverse signal control, Q 12 and Q 13 This is controlled by the detection module 30. V C1 via the second intermediate output node V 2. Operational amplifier U 5. Non-inverting inputs V C2 via the first intermediate output node V 1. Under the condition of connecting the inverting input terminal, assume , U The initial output of 6 is low. At this time, the switch... S 1. Close the first branch to make it conductive. V C1 It continues to decrease. Until... , U 6 output V d The switch transitions to a high level. S 2. When the second branch is closed, it becomes conductive; when the second branch is open, it becomes conductive. V C2 It continues to decrease. Until... , U 6 outputV d The signal transitions to a low level, and the above process is repeated. All operational amplifiers in this invention embodiment can have their negative power supply terminal grounded, making... Furthermore, based on the previous formula, we can know that However, in V C1 via the first intermediate output node V 1. Connect to operational amplifier U 5. Inverting input terminal, V C2 via the second intermediate output node V 2. Under the condition of connecting the non-inverting input terminal, assume , U The initial output of 6 is low, switch S 2. Close the second branch to make it conductive. V C2 This will continue to decrease, making U Output 6 remains low until .

[0024] In specific examples, the preferred option is... Reference voltage setting: , , And the capacitor during the simulation C 1. C 2. No energy storage, overall waveform switching is as follows Figure 5 As shown. If ,but U 6. Output is high level, switch S When the second branch is closed, the second branch is open. V C2 Continuously decreasing, the waveform is as follows Figure 6a As shown; if ,but U 6. Output is low, switch S When the circuit is closed (1), the first branch is open. V C1 Continuously decreasing, the waveform is as follows Figure 6b As shown.

[0025] In some embodiments of the present invention, such as Figure 2 , Figure 4b and Figure 4c As shown, the control module 20 is also connected to the detection module 30, and the control module 20 also includes a twelfth MOSFET. Q 12 and the thirteenth MOSFET Q 13 The detection module 30 includes a seventh operational amplifier. U 7th to 10th operational amplifiers U10 ,in: Seventh Operational Amplifier U The inverting input of resistor 7 passes through the nineteenth resistor. R 19 Connect the first switching transistor S The drain of 1 (see V L1 (at the location), another path passes through the twentieth resistor. R 20 Connect the seventh operational amplifier U The output of 7, the seventh operational amplifier U The non-inverting input of 7 passes through the twenty-first resistor. R 21 Connect the first input terminal of the energy management circuit 100 V C1 Another path passes through the twenty-second resistor. R 22 Ground, seventh operational amplifier U The output of 7 is connected to the eighth operational amplifier. U The non-inverting input of 8, the eighth operational amplifier U The inverting input of 8 is connected to the third reference voltage. V ref3 Eighth operational amplifier U The output terminal of 8 is connected to the thirteenth MOSFET. Q 13 gate (see) V (4 locations), the thirteenth MOSFET Q 13 The drain is connected to the second switching transistor. S Gate 2, the thirteenth MOSFET Q 13 The source is grounded; And / or, the ninth operational amplifier U The inverting input of 9 passes through the twenty-third resistor. R 23 Connect the second switching transistor S 2's drain (see V L2 (at the location), another path passes through the twenty-fourth resistor. R 24 Connect to the ninth operational amplifier U The output of 9, the ninth operational amplifier U The non-inverting input of 9 passes through the 25th resistor. R 25 Connect the second input terminal of the energy management circuit 100 V C2 Another path passes through the twenty-sixth resistor. R 26Ground, Ninth Operational Amplifier U The output of 9 is connected to the tenth operational amplifier. U 10 The non-inverting input terminal of the tenth operational amplifier U 10 The inverting input terminal is connected to the third reference voltage. V ref3 10th operational amplifier U 10 The output terminal is connected to the twelfth MOSFET. Q 12 gate (see) V 3 locations), the twelfth MOSFET Q 12 The drain of the first switching transistor is connected. S Gate of 1, twelfth MOSFET Q 12 The source is grounded. In specific implementation, the twelfth MOSFET... Q 12 Up to the thirteenth MOSFET Q 13 Both can be N-type MOSFETs.

[0026] Figure 4c The circuit diagram of the detection module 30 in this invention shows that the detection module 30 and the control module 20 form a coordinated control envelope: when a fault occurs in the first branch, the detection module 30 immediately turns on the switch of the second branch; when a fault occurs in the second branch, it immediately turns on the switch of the first branch, ensuring stable power supply to the system. The detection module 30 includes a first detection circuit and a second detection circuit. The first detection circuit is used to compare the energy storage capacitors. C 1 and switch S 1 drain node V L1 The voltage signal is used by the second detection circuit to compare the energy storage capacitor. C 2 and switch S 2 drain nodes V L2 The voltage signal. If the difference is greater than the reference value, the branch may be faulty. Quickly switch to another branch. Due to the existence of the parallel control envelope, it will not affect the circuit's alternating conduction function.

[0027] Specifically, the first detection circuit consists of a subtractor U 7 and comparator U Composed of 8, V C1 Connected to the subtractor (i.e., operational amplifier) U 7) Non-inverting input terminal, V L1 Connect the inverting input terminal. Connect the operational amplifier. U7. Output signal and third reference voltage V ref3 If a comparison is made, Then output a high level to Q 13 The gate turns it on, thus switching the second branch. S 2. Conduction. For example... Figure 7a As shown, if the first branch fails and Under the control of the output of the first detection circuit, the second branch remains continuously conducting. Since the switch's on-state voltage is relatively small, V ref3 Choose around 1V.

[0028] Similarly, in the second detection circuit V C2 Connected to the subtractor (i.e., operational amplifier) U 9) Non-inverting input terminal, V L2 Connect to the inverting input terminal. If Then output a high level to Q 12 The gate turns it on, thus switching the first branch. S 1. Conduction. (e.g.) Figure 7b As shown, if the second branch fails and Then, under the control of the output of the second detection circuit, the first branch continues to conduct.

[0029] In the embodiment shown in the figure, Figure 5 Initial conditions: , ; Figures 6a-6b Initial conditions: (a) , (b) , ; Figures 7a-7b Initial conditions: (a) , (b) , .

[0030] In some embodiments of the present invention, the energy management circuit 100 further includes a reference voltage module, such as... Figure 3 As shown, the reference voltage module includes an eleventh operational amplifier. U 11 Zener diode D z ,in: Eleventh operational amplifier U 11 The non-inverting input terminal passes through the 27th resistor. R 27Connect to the eleventh operational amplifier U 11 One output terminal is connected to a Zener diode. D z The negative terminal, Zener diode D z The positive terminal is grounded; Eleventh operational amplifier U 11 The inverting input terminal is connected to the 28th resistor. R 28 Connect to the eleventh operational amplifier U 11 The output terminal, another path goes through the twenty-ninth resistor. R 29 Grounding; Eleventh operational amplifier U 11 The output terminal is sequentially connected to the thirtieth resistor. R 30 The thirty-first resistor R 31 and the thirty-second resistor R 32 Ground, eleventh operational amplifier U 11 Output terminal and thirtieth resistor R 30 The connection point between them outputs the first reference voltage. V ref1 The thirtieth resistor R 30 and the thirty-first resistor R 31 The connection point between them outputs a second reference voltage. V ref2 Furthermore, the thirty-first resistor R 31 and the thirty-second resistor R 32 The connection point between them outputs a third reference voltage. V ref3 .

[0031] In this embodiment, all three reference voltages in the figure can be provided by a reference voltage module, such as... Figure 3 As shown. Its expression is: ; ; ; In the formula, U DZ Zener diode D zThe voltage at both ends.

[0032] In summary, this invention proposes an energy management circuit for environmental energy harvesting systems that allows for alternating conduction of dual energy sources. This circuit enables alternating power supply from two energy sources, avoiding coupling effects between the two power supply branches and reducing energy losses during transmission. Furthermore, different conduction strategies are adopted based on the charging characteristics of the supercapacitor, effectively improving the overall energy harvesting efficiency of the system. In addition, if a component in a single branch fails, the detection module can quickly switch to the other branch and maintain continuous conduction, ensuring stable power supply to the load.

[0033] The present invention has the following beneficial effects: 1. In an environmental energy harvesting system, simultaneous conduction of two power supply branches can lead to current coupling between the branches, significantly reducing energy harvesting efficiency and increasing system energy loss. This invention addresses this by processing the terminal voltage of the energy harvesting device equipped with the energy storage capacitor via a subtractor and outputting it to a comparator. The comparator uses zero potential as a reference threshold, forming a hysteresis comparator with zero-crossing detection. Based on the output signal of this hysteresis comparator, the system dynamically controls the conduction state of the two branches, ensuring that only one power generation branch is in the conducting state at any given time. The use of the hysteresis comparator effectively prevents frequent switching back and forth when the voltages of the two branches are close, thus ensuring the stability of power supply branch switching. Coupling interference refers to the abnormal operation of branches caused by the instantaneous differences in their output characteristics when different power generation branches simultaneously supply power to the load. This reduces efficiency, causes interference, and may damage components.

[0034] 2. The selection module designed in this invention can switch the conduction strategy according to the different terminal voltages of the two branch energy storage capacitors, thereby enabling the energy harvesting device to extract more power. When the voltages of both branch energy storage capacitors are less than the maximum power point voltage, the branch with the higher voltage has a larger energy storage power and the branch with the lower terminal voltage is turned on. Conversely, when the voltages of both branch energy storage capacitors are greater than the maximum power point voltage, the branch with the lower voltage has a larger energy storage power and the branch with the higher terminal voltage is turned on.

[0035] 3. The fault protection module (i.e., detection module) designed in this invention can ensure stable power supply to another branch when a single branch fails, thus enhancing the system's anti-interference capability. This module is also applicable to other alternating conduction circuits, including alternating conduction circuits controlled by timing.

[0036] 4. By utilizing the characteristics of CMOS circuits and the voltage divider principle, this invention effectively reduces the control voltage of the switch, achieves greater passivity in the circuit, increases the practicality of the circuit, and can be widely used in dual-energy-source self-powered systems (such as environmental energy harvesting self-powered systems, or can be replaced by dual-energy-source energy storage power supply systems in other scenarios).

[0037] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. An energy management circuit with alternating conduction of dual energy sources, characterized in that, The energy management circuit, having a first input terminal, a second input terminal, and an output terminal, includes a selection module, a control module, a first switching transistor, and a second switching transistor, wherein: The input terminal of the control module is connected to the selection module, and the output terminal of the control module is connected to the gate of the first switching transistor and the gate of the second switching transistor, respectively. The source of the first switching transistor is connected to the first input terminal of the energy management circuit, which is used to connect to the first energy storage capacitor of the first energy harvesting device. The drain of the first switching transistor is connected to the output terminal of the energy management circuit via a diode. The source of the second switching transistor is connected to the second input terminal of the energy management circuit, which is used to connect to the second energy storage capacitor of the second energy harvesting device. The drain of the second switching transistor is connected to the output terminal of the energy management circuit via a diode. The output terminal of the energy management circuit is used to supply power to the load via a voltage converter.

2. The energy management circuit with alternating conduction of dual energy sources according to claim 1, characterized in that, The selection module includes a first operational amplifier to a fourth operational amplifier and a first MOSFET to an eighth MOSFET, wherein: The first input terminal of the energy management circuit is grounded via a first resistor and a second resistor in sequence, and the second input terminal of the energy management circuit is grounded via a fourth resistor and a third resistor in sequence; The inverting input terminal of the first operational amplifier and the non-inverting input terminal of the second operational amplifier are both connected to the connection point between the first resistor and the second resistor, and the non-inverting input terminal of the first operational amplifier and the non-inverting input terminal of the third operational amplifier are both connected to the first reference voltage. The inverting input terminals of the second operational amplifier and the fourth operational amplifier are both connected to the second reference voltage, and the inverting input terminal of the third operational amplifier and the non-inverting input terminal of the fourth operational amplifier are both connected to the connection point between the fourth resistor and the third resistor. The outputs of the first operational amplifier to the fourth operational amplifier are all connected to the intermediate control node, and the intermediate control node is connected to a high level via the fifth resistor.

3. The energy management circuit with alternating conduction of dual energy sources according to claim 2, characterized in that, First reference voltage V ref1 The voltage corresponding to the maximum energy storage power of each energy storage capacitor V m The following relationship must be satisfied: ； And / or, the second reference voltage is the lowest operating voltage of the voltage converter.

4. The energy management circuit with alternating conduction of dual energy sources according to claim 2, characterized in that, The gate of the first MOS transistor is connected to the intermediate control node, and its drain is connected to the first input terminal of the energy management circuit via a sixth resistor. The other drain is connected to the gate of the second MOS transistor and the gate of the fifth MOS transistor. The source of the first MOS transistor is grounded. The drain of the second MOS transistor is connected to the first input terminal of the energy management circuit via a seventh resistor, and the other path is connected to the gate of the sixth MOS transistor. The source of the second MOS transistor is grounded. The gate of the third MOS transistor is connected to the intermediate control node, and its drain is connected to the second input terminal of the energy management circuit via the eighth resistor. The other drain is connected to the gate of the fourth MOS transistor and the gate of the eighth MOS transistor. The source of the third MOS transistor is grounded. The drain of the fourth MOS transistor is connected to the second input terminal of the energy management circuit via the ninth resistor, and the other path is connected to the gate of the seventh MOS transistor. The source of the fourth MOS transistor is grounded. The source of the fifth MOSFET and the source of the sixth MOSFET are both connected to the first input terminal of the power management circuit. The source of the seventh MOSFET and the source of the eighth MOSFET are both connected to the second input terminal of the power management circuit. The drain of the fifth MOSFET and the drain of the seventh MOSFET are both connected to the first intermediate output node. The drain of the sixth MOSFET and the drain of the eighth MOSFET are both connected to the second intermediate output node.

5. The energy management circuit with alternating conduction of dual energy sources according to claim 4, characterized in that, The intermediate control node is connected to the output terminals of the first operational amplifier to the fourth operational amplifier, respectively, via the first diode to the fourth diode. And / or, a fifth diode and a seventh diode are respectively connected between the drain of the fifth MOS transistor and the drain of the seventh MOS transistor and the first intermediate output node, and a sixth diode and an eighth diode are respectively connected between the drain of the sixth MOS transistor and the drain of the eighth MOS transistor and the second intermediate output node.

6. The energy management circuit with alternating conduction of dual energy sources according to any one of claims 1-5, characterized in that, The control module includes a fifth operational amplifier, a sixth operational amplifier, and MOSFETs nine through eleven, wherein: The inverting input of the fifth operational amplifier is connected to the first intermediate output node via the tenth resistor, and to the output of the fifth operational amplifier via the eleventh resistor. The non-inverting input of the fifth operational amplifier is connected to the second intermediate output node via the twelfth resistor, and to ground via the thirteenth resistor. The output of the fifth operational amplifier is connected to the inverting input of the sixth operational amplifier. One of the non-inverting input terminals of the sixth operational amplifier is grounded through the fourteenth resistor, and the other is connected to the output terminal of the sixth operational amplifier through the fifteenth resistor. The output terminal of the sixth operational amplifier is connected to the gate of the ninth MOS transistor and the gate of the tenth MOS transistor. The drain of the ninth MOS transistor is connected to the first input terminal of the energy management circuit via the sixteenth resistor, and the other path is connected to the gate of the eleventh MOS transistor. The source of the ninth MOS transistor is grounded. The drain of the tenth MOS transistor is connected to the second input terminal of the energy management circuit via the eighteenth resistor, and the other path is connected to the gate of the second switching transistor. The source of the tenth MOS transistor is grounded. The drain of the eleventh MOS transistor is connected to the first input terminal of the energy management circuit via the seventeenth resistor, and the other path is connected to the gate of the first switching transistor. The source of the eleventh MOS transistor is grounded.

7. The energy management circuit with alternating conduction of dual energy sources according to claim 6, characterized in that, The ratio of the first resistor to the second resistor is the same as the ratio of the fourth resistor to the third resistor; And / or, the resistance values ​​of the tenth to thirteenth resistors are the same.

8. The energy management circuit with alternating conduction of dual energy sources according to claim 6, characterized in that, The control module is also connected to a detection module. The control module further includes a twelfth MOSFET and a thirteenth MOSFET. The detection module includes operational amplifiers seven through ten, wherein: The inverting input of the seventh operational amplifier has one path connected to the drain of the first switching transistor via the nineteenth resistor, and the other path connected to the output of the seventh operational amplifier via the twentieth resistor. The non-inverting input of the seventh operational amplifier has one path connected to the first input of the energy management circuit via the twenty-first resistor, and the other path connected to ground via the twenty-second resistor. The output of the seventh operational amplifier is connected to the non-inverting input of the eighth operational amplifier. The inverting input of the eighth operational amplifier is connected to the third reference voltage. The output of the eighth operational amplifier is connected to the gate of the thirteenth MOS transistor. The drain of the thirteenth MOS transistor is connected to the gate of the second switching transistor. The source of the thirteenth MOS transistor is grounded. And / or, one inverting input terminal of the ninth operational amplifier is connected to the drain of the second switching transistor via the twenty-third resistor, and the other is connected to the output terminal of the ninth operational amplifier via the twenty-fourth resistor. One non-inverting input terminal of the ninth operational amplifier is connected to the second input terminal of the energy management circuit via the twenty-fifth resistor, and the other is grounded via the twenty-sixth resistor. The output terminal of the ninth operational amplifier is connected to the non-inverting input terminal of the tenth operational amplifier. The inverting input terminal of the tenth operational amplifier is connected to the third reference voltage. The output terminal of the tenth operational amplifier is connected to the gate of the twelfth MOS transistor. The drain of the twelfth MOS transistor is connected to the gate of the first switching transistor, and the source of the twelfth MOS transistor is grounded.

9. The energy management circuit with alternating conduction of dual energy sources according to claim 8, characterized in that, The energy management circuit also includes a reference voltage module, which comprises an eleventh operational amplifier and a Zener diode, wherein: One of the non-inverting input terminals of the eleventh operational amplifier is connected to the output terminal of the eleventh operational amplifier via the twenty-seventh resistor, and the other is connected to the negative terminal of the Zener diode, with the positive terminal of the Zener diode grounded. One of the inverting input terminals of the eleventh operational amplifier is connected to the output terminal of the eleventh operational amplifier through the twenty-eighth resistor, and the other is grounded through the twenty-ninth resistor. The output terminal of the eleventh operational amplifier is grounded sequentially through the thirtieth, thirty-first, and thirty-second resistors. The connection point between the output terminal of the eleventh operational amplifier and the thirtieth resistor outputs the first reference voltage. The connection point between the thirtieth and thirty-first resistors outputs the second reference voltage. The connection point between the thirty-first and thirty-second resistors outputs the third reference voltage.

10. The energy management circuit with alternating conduction of dual energy sources according to claim 8, characterized in that, Both the first and second switching transistors are P-type MOSFETs; And / or, the first to the fourth MOSFETs are all N-type MOSFETs; And / or, the fifth to eighth MOS transistors are all P-type MOS transistors; And / or, the ninth to eleventh MOS transistors are all N-type MOS transistors; And / or, the twelfth to thirteenth MOS transistors are all N-type MOS transistors.

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