DC transmission line voltage difference energy harvesting system and DC transmission system

Abstract

The present application relates to a DC transmission line pressure difference energy harvesting system and a DC power transmission system, wherein the DC transmission line pressure difference energy harvesting system includes a pressure difference energy collection module, a voltage stabilizing module and a starting module. The input end of the pressure difference energy harvesting module is used to connect to the DC transmission line, and the pressure difference energy harvesting module is used to convert the pressure difference of the DC transmission line into the power supply voltage of the monitoring equipment of the DC transmission line; the input end of the voltage stabilizing module is connected to the output end of the pressure difference energy harvesting module, and the output end of the voltage stabilizing module is used to connect to the monitoring equipment; the input end of the starting module is used to connect to the DC transmission line, and the output end of the starting module is connected to the power supply end of the pressure difference energy harvesting module, and the starting module is used to convert the pressure difference on the DC transmission line into the starting voltage of the pressure difference energy harvesting module; the starting voltage of the starting module is less than the starting voltage of the pressure difference energy harvesting module. The DC transmission line pressure difference energy harvesting system can stably and reliably draw power from the DC transmission line.

Description

Technical Field

[0001] The present application relates to the field of direct current (DC) power transmission technology, and in particular to a DC power transmission line voltage difference energy harvesting system and a DC power transmission system. Background Art

[0002] With the development of DC transmission systems, monitoring equipment for DC transmission lines plays a vital role in the stable operation of DC transmission systems. The autonomous power supply of DC transmission line monitoring equipment is conducive to expanding its application areas and further improving the reliability of power systems.

[0003] However, the existing autonomous power supply mode of the monitoring equipment of the DC transmission line is limited by the power supply environment and hardware requirements, making it difficult to realize the autonomous power supply of the monitoring equipment of the DC transmission line.

[0004] Therefore, providing a stable and reliable energy extraction method for monitoring equipment on DC transmission lines is an urgent problem to be solved. Summary of the Invention

[0005] Based on this, it is necessary to provide a DC transmission line voltage difference energy harvesting system and a DC transmission system that can achieve stable and reliable energy harvesting.

[0006] In a first aspect, the present application provides a DC transmission line pressure difference energy harvesting system, the DC transmission line pressure difference energy harvesting system comprising:

[0007] A pressure difference energy collection module, the input end of which is used to connect to a DC transmission line, and the pressure difference energy collection module is used to convert the voltage difference of the DC transmission line into a supply voltage for a monitoring device of the DC transmission line;

[0008] A voltage stabilizing module, wherein the input end of the voltage stabilizing module is connected to the output end of the pressure difference energy harvesting module, and the output end of the voltage stabilizing module is used to connect to the monitoring equipment;

[0009] A starting module, wherein the input end of the starting module is used to connect to the DC transmission line, the output end of the starting module is connected to the power supply end of the pressure difference energy harvesting module, and the starting module is used to convert the voltage difference on the DC transmission line into the starting voltage of the pressure difference energy harvesting module;

[0010] The starting voltage of the starting module is lower than the starting voltage of the pressure difference energy harvesting module.

[0011] In one embodiment, the startup module includes:

[0012] A first energy storage filter capacitor, wherein an input end of the first energy storage filter capacitor is used to connect to a DC transmission line;

[0013] A boost circuit, wherein an input end of the boost circuit is connected to an output end of the first energy storage filter capacitor;

[0014] An energy storage capacitor, wherein an input end of the energy storage capacitor is connected to an output end of the boost circuit;

[0015] The DC-DC conversion circuit has an input end connected to the output end of the energy storage capacitor, and an output end of the DC-DC conversion circuit is connected to the power supply end of the pressure difference energy collection module.

[0016] In one embodiment, the power supply end of the pressure difference energy harvesting module is further connected to the output end of the pressure difference energy harvesting module, and the startup module further includes:

[0017] A power supply control circuit, wherein a first input terminal of the power supply control circuit is connected to an output terminal of the pressure difference energy harvesting module, and a control terminal of the power supply control circuit is connected to a controlled terminal of the DC-DC conversion circuit;

[0018] The power supply control circuit is used to obtain the output voltage of the pressure difference energy collection module, and control the DC-DC conversion circuit to stop working when the output voltage of the pressure difference energy collection module is greater than or equal to a preset threshold.

[0019] In one embodiment, the second input terminal of the power supply control circuit is connected to the output terminal of the energy storage capacitor;

[0020] The power supply control circuit is further configured to obtain the voltage of the energy storage capacitor and control the DC-DC conversion circuit to operate when the voltage of the energy storage capacitor is greater than or equal to a preset threshold.

[0021] In one embodiment, the pressure difference energy harvesting module includes:

[0022] A second energy storage filter capacitor, wherein the input end of the second energy storage filter capacitor is used to connect to a DC transmission line;

[0023] A boost module, wherein the input end of the boost module is connected to the output end of the second energy storage filter capacitor, the output end of the boost module is used to connect to the monitoring equipment, and the power supply end of the boost module is connected to the output end of the starting module.

[0024] In one embodiment, the boost module includes:

[0025] A power circuit, wherein an input end of the power circuit is connected to an output end of the second energy storage filter capacitor, and an output end of the power circuit is used to connect to a monitoring device;

[0026] The driving control circuit has a power supply end connected to the output end of the starting module, and a control end of the driving control circuit is connected to the controlled end of the power circuit.

[0027] In one embodiment, the boost module further includes:

[0028] The diode has an anode connected to the input end of the power circuit, and a cathode connected to the power supply end of the drive control circuit.

[0029] In one embodiment, the DC transmission line voltage difference energy harvesting system further includes:

[0030] The lithium battery charge and discharge management module has an input end connected to the output end of the pressure difference energy collection module, and the output end of the lithium battery charge and discharge management module is used to connect to the monitoring equipment.

[0031] In one embodiment, the lithium battery charge and discharge management module includes:

[0032] A charging circuit, wherein an input end of the charging circuit is connected to an output end of the pressure difference energy harvesting module;

[0033] A lithium battery, wherein the input terminal of the lithium battery is connected to the output terminal of the charging circuit;

[0034] The discharge circuit has an input end connected to the output end of the lithium battery, and an output end of the discharge circuit is used to connect to a monitoring device.

[0035] In a second aspect, the present application further provides a direct current transmission system, the direct current transmission system comprising:

[0036] DC transmission lines;

[0037] Monitoring equipment, the monitoring equipment is set on the DC transmission line, and the monitoring equipment is used to monitor the DC transmission line;

[0038] And the DC transmission line voltage difference energy acquisition system in the above embodiment.

[0039] The above-mentioned DC transmission line voltage difference energy harvesting system and DC transmission system have at least the following beneficial effects:

[0040] By incorporating a startup module, the system can automatically start by harvesting energy from the DC transmission line itself, using the DC line voltage differential energy harvesting system. This system then provides power to monitoring equipment, reducing reliance on external energy sources. It operates with minimal line voltage differentials and offers strong adaptability, providing a stable power supply even under voltage fluctuations or line load variations. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the conventional technology, the following briefly introduces the drawings required for use in the embodiments or the conventional technology descriptions. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0042] Figure 1 Schematic diagram of the structure of a DC transmission line voltage difference energy extraction system in one embodiment;

[0043] Figure 2 is a schematic structural diagram of a startup module in one embodiment;

[0044] Figure 3 is a schematic structural diagram of a startup module in another embodiment;

[0045] Figure 4 Schematic diagram of the structure of a boost circuit, a DC-DC conversion circuit, and a power supply control circuit in one embodiment;

[0046] Figure 5 Schematic diagram of voltage waveforms of the APX809-46SAG-7 chip in one embodiment;

[0047] Figure 6 Schematic diagram of the structure of a pressure difference energy harvesting module in one embodiment;

[0048] Figure 7 Schematic diagram of the structure of a DC transmission line voltage difference energy extraction system in another embodiment;

[0049] Figure 8 is a schematic structural diagram of a charging circuit and a discharging circuit in one embodiment;

[0050] Figure 9 FIG. 4 is a schematic structural diagram of a voltage stabilizing module in an embodiment. DETAILED DESCRIPTION

[0051] To facilitate understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings. The accompanying drawings provide embodiments of the present application. However, the present application may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0053] It will be understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor without departing from the scope of this application. The first resistor and the second resistor are both resistors, but they are not the same resistor.

[0054] It can be understood that the “connection” in the following embodiments should be understood as “electrical connection”, “communication connection”, etc. if there is transmission of electrical signals or data between the connected circuits, modules, units, etc.

[0055] It is understood that “at least one” refers to one or more, “a plurality” refers to two or more, and “at least a portion of an element” refers to a portion or all of an element.

[0056] When used herein, the singular forms "a", "an", and "the" may also include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.

[0057] In an exemplary embodiment, Figure 1 As shown, the present application provides a DC transmission line pressure difference energy harvesting system, which includes a pressure difference energy harvesting module 2, a voltage stabilizing module 4 and a starting module 6. The input end of the pressure difference energy harvesting module 2 is used to connect to the DC transmission line 100, and the pressure difference energy harvesting module 2 is used to convert the pressure difference of the DC transmission line 100 into the power supply voltage of the monitoring device 300 of the DC transmission line 100; the input end of the voltage stabilizing module 4 is connected to the output end of the pressure difference energy harvesting module 2, and the output end of the voltage stabilizing module 4 is used to connect to the monitoring device 300; the input end of the starting module 6 is used to connect to the DC transmission line 100, and the output end of the starting module 6 is connected to the power supply end of the pressure difference energy harvesting module 2, and the starting module 6 is used to convert the pressure difference on the DC transmission line 100 into the starting voltage of the pressure difference energy harvesting module 2; the starting voltage of the starting module 6 is less than the starting voltage of the pressure difference energy harvesting module 2.

[0058] Among them, the pressure difference energy collection module 2 is used to collect the voltage difference on the DC transmission line 100 and convert it into electrical energy to provide the DC voltage required for the monitoring device 300 to work. In the initial stage of the startup of the DC transmission line pressure difference energy collection system, since the pressure difference energy collection module 2 requires a sufficiently large voltage to start, and the pressure difference on the DC transmission line 100 is not enough to start the module, the starting module 6 is required to provide this initial energy, that is, to provide a starting voltage for the pressure difference energy collection module 2 so that it can start working. When providing the DC voltage required for the monitoring device 300 to work, since the energy obtained from the transmission line may have voltage fluctuations, the voltage stabilizing module 4 is used to eliminate the above-mentioned voltage fluctuations, ensure that the voltage output to the monitoring device 300 is constant, and prevent damage to the equipment or unstable operation caused by voltage fluctuations. It should be noted that the starting voltage of the starting module 6 is lower than the starting voltage of the pressure difference energy collection module 2. Its purpose is to ensure that the starting module 6 can work normally based on the low voltage difference of the DC transmission line 100, and ensure the normal startup of the pressure difference energy collection module 2.

[0059] For example, for a DC transmission line 100 with a resistivity of ρ and a length of L, the resistance value R = ρL. According to Ohm's law, when a current I flows through the line, the resulting voltage difference V is V = IρL. Because the resistivity ρ is very small and the length L is not large, the resulting voltage difference V is generally very low. Although the resulting voltage difference V is extremely low, because the current I in the DC transmission line 100 is very large and relatively stable over a short period of time, this ultra-low voltage difference V still contains a certain amount of energy. The pressure difference energy harvesting module 2 collects the ultra-low voltage difference across the DC transmission line 100 in real time and boosts this ultra-low voltage difference to a high voltage with high power. The voltage stabilizing module 4 then converts the high voltage output by the pressure difference energy harvesting module 2 into a stable voltage to power electronic loads such as monitoring equipment 300 (e.g., sensors) on the DC transmission line 100. Because the power devices within the pressure difference energy harvesting module 2 require high power and a high startup voltage threshold, the supply voltage and power provided to the pressure difference energy harvesting module 2 must be sufficiently high to operate these power devices. However, since the value of the ultra-low voltage difference at both ends of the DC transmission line 100 is too low, in the initial stage of startup operation, it is impossible to directly power itself through the pressure difference energy collection module 2 to drive the above-mentioned power devices to work, so as to complete the self-start of the pressure difference energy collection module 2. Based on the above reasons, the ultra-low voltage difference is converted into a sub-high voltage with weak power by using the starting module 6. The sub-high voltage is sufficient to power the pressure difference energy collection module 2 to drive the above-mentioned power devices to work, so that the pressure difference energy collection module 2 can start working and output a high voltage with high power. After the pressure difference energy collection module 2 runs stably, the above-mentioned high voltage can also be used to power the pressure difference energy collection module 2 to drive the above-mentioned power devices to work normally, so that the pressure difference energy collection module 2 can work normally. It should be noted that the power level of the starting module 6 is relatively low, and it is mostly composed of micro-power consumption chips, so that it can self-start under ultra-low voltage difference power supply conditions.

[0060] The DC line voltage differential energy harvesting system, equipped with a startup module, can harvest energy from the DC line itself to self-start the system, thereby providing power to monitoring equipment and reducing reliance on external energy sources. It operates with minimal line voltage differentials and exhibits strong adaptability, providing a stable power supply to monitoring equipment even under voltage fluctuations or line load variations.

[0061] In an exemplary embodiment, Figure 2As shown, the startup module 6 includes a first energy storage filter capacitor 62, a boost circuit 64, an energy storage capacitor C5, and a DC-DC conversion circuit 66. The input end of the first energy storage filter capacitor 62 is used to connect to the DC transmission line 100; the input end of the boost circuit 64 is connected to the output end of the first energy storage filter capacitor 62; the input end of the energy storage capacitor C5 is connected to the output end of the boost circuit 64; the input end of the DC-DC conversion circuit 66 is connected to the output end of the energy storage capacitor C5, and the output end of the DC-DC conversion circuit 66 is connected to the power supply end of the pressure difference energy harvesting module 2.

[0062] Exemplarily, the first energy storage filter capacitor 62 is connected to any two contact points of the DC transmission line 100, the boost circuit 64 converts the ultra-low voltage across the first energy storage filter capacitor 62 into a sub-high voltage, and the energy of the sub-high voltage is stored in the energy storage capacitor C5. The DC-DC conversion circuit 66 converts the sub-high voltage across the energy storage capacitor C5 into a stable sub-high voltage to power the pressure difference energy collection module 2.

[0063] In this embodiment, the startup module includes an energy storage capacitor, which can store energy of the second highest voltage therein to ensure that the startup voltage of the pressure difference energy harvesting module is reached when power is subsequently supplied to the pressure difference energy harvesting module.

[0064] In an exemplary embodiment, Figure 3 As shown, the power supply end of the pressure difference energy harvesting module 2 is also connected to the output end of the pressure difference energy harvesting module 2, and the starting module 6 further includes a power supply control circuit 68. A first input end of the power supply control circuit 68 is connected to the output end of the pressure difference energy harvesting module 2, and a control end of the power supply control circuit 68 is connected to a controlled end of the DC-DC conversion circuit 66; wherein the power supply control circuit 68 is used to obtain the output voltage of the pressure difference energy harvesting module 2, and control the DC-DC conversion circuit 66 to stop working when the output voltage of the pressure difference energy harvesting module 2 is greater than or equal to a preset threshold.

[0065] Among them, such as Figure 4 As shown, the boost circuit 64 can be composed of an LTC3108 chip and its peripheral circuits; the DC-DC conversion circuit 66 can be composed of a TX4401 chip and its peripheral circuits; the power supply control circuit 68 can be composed of an APX809-46SAG-7 chip and its peripheral circuits; the preset threshold value can refer to the maximum charging voltage of the energy storage capacitor C5. Since the maximum charging voltage of the energy storage capacitor C5 is generally greater than the starting voltage of the pressure difference energy harvesting module 2, the maximum charging voltage of the energy storage capacitor C5 can be directly used as the above-mentioned preset threshold value.

[0066] For example, the maximum charging voltage of the energy storage capacitor C5 can be set to V1max through the pins VS1 and VS2 of the LTC3108 chip. In actual operation, the ultra-low voltage across the first energy storage filter capacitor 62 is used to charge the energy storage capacitor C5 through the LTC3108 chip. Figure 5 As shown in the figure, when the voltage of the energy storage capacitor C5 is higher than the threshold voltage Vth of the APX809-46SAG-7 chip, the timing starts, and after a certain delay time T Delay Afterwards, when the voltage of the energy storage capacitor C5 reaches the maximum charging voltage V1max, the reset pin of the APX809-46SAG-7 chip outputs a high level to enable the DC-DC conversion circuit 66, causing the DC-DC conversion circuit 66 to start working. The energy stored in the energy storage capacitor C5 provides a starting voltage for the pressure difference energy harvesting module 2 through the DC-DC conversion circuit 66. However, when it is detected that the output voltage of the pressure difference energy harvesting module 2 is greater than the maximum charging voltage V1max, it means that the output voltage of the pressure difference energy harvesting module 2 can meet the voltage required to drive the power devices within itself to operate normally. Therefore, the reset pin of the APX809-46SAG-7 chip can output a low level at this time to shut down the DC-DC conversion circuit 66, thereby reducing power consumption and achieving self-power supply through the pressure difference energy harvesting module 2 itself.

[0067] The relationship between the threshold voltage Vth, the maximum charging voltage V1max, the capacitance C of the energy storage capacitor C5 and the energy P required to start the pressure difference energy harvesting module 2 is:

[0068]

[0069] According to the selection of different chips of the pressure difference energy harvesting module 2, the energy p required for its startup is determined. Similarly, the threshold voltage of the power supply control circuit 68 is also determined according to the selection of its chip. Therefore, the capacitance of the energy storage capacitor C5 can be selected according to the set maximum charging voltage V1max and the above formula.

[0070] In this embodiment, through the power supply control circuit, when the output voltage of the pressure difference energy collection module is greater than or equal to the preset threshold, the DC-DC conversion circuit is controlled to stop working, and the pressure difference energy collection module itself is self-powered to achieve the effect of reducing power consumption.

[0071] In an exemplary embodiment, Figure 3 As shown, the second input end of the power supply control circuit 68 is connected to the output end of the energy storage capacitor C5; wherein, the power supply control circuit 68 is also used to obtain the voltage of the energy storage capacitor C5, and control the DC-DC conversion circuit 66 to operate when the voltage of the energy storage capacitor C5 is greater than or equal to a preset threshold.

[0072] For example, as described above, Figure 4 Taking the circuit diagram in FIG as an example, the reset pin of the APX809-46SAG-7 chip will output a high level to enable the DC-DC converter circuit 66 only when the voltage of the energy storage capacitor C5 reaches the maximum charging voltage V1max, so that the DC-DC converter circuit 66 starts to work. th When , the reset pin of the APX809-46SAG-7 chip outputs a low level to turn off the DC-DC conversion circuit 66, and the output voltage of the DC-DC conversion circuit 66 is 0.

[0073] In this embodiment, the DC-DC conversion circuit is controlled to operate only when the voltage of the energy storage capacitor is greater than or equal to a preset threshold value, thereby ensuring that the output voltage of the DC-DC conversion circuit is sufficient to start the pressure difference energy module, thereby improving the safety of the DC transmission line pressure difference energy extraction system.

[0074] In an exemplary embodiment, Figure 6 As shown, the pressure difference energy harvesting module 2 includes a second energy storage filter capacitor 22 and a boost module 24. The input end of the second energy storage filter capacitor 22 is used to connect to the DC transmission line 100; the input end of the boost module 24 is connected to the output end of the second energy storage filter capacitor 22, and the output end of the boost module 24 is used to connect to the monitoring device 300. The power supply end of the boost module 24 is connected to the output end of the starting module 6.

[0075] The boost module 24 may be a high-gain boost circuit. Compared with the boost circuit 64 in the startup module 6 , the startup voltage of the boost module 24 is higher.

[0076] For example, a connecting conductor and a connecting wire are used to direct the ultra-low voltage differential generated by a section of DC transmission line 100 to the two ends of a second energy storage filter capacitor 22. The voltage differential on DC transmission line 100 charges the second energy storage filter capacitor 22, causing the second energy storage filter capacitor 22 to obtain an ultra-low voltage. The output end of the second energy storage filter capacitor 22 is connected to the input end of a boost module 24, which converts the ultra-low voltage across the second energy storage filter capacitor 22 into a high voltage.

[0077] In an exemplary embodiment, the power supply end of the boost module 24 may also be connected to the output end of the boost module 24 so that the boost module 24 can supply power to itself.

[0078] In an exemplary embodiment, Figure 6As shown, the boost module 24 includes a power circuit 242 and a drive control circuit 244. The input end of the power circuit 242 is connected to the output end of the second energy storage filter capacitor 22, and the output end of the power circuit 242 is used to connect to the monitoring device 300; the power supply end of the drive control circuit 244 is connected to the output end of the starting module 6, and the control end of the drive control circuit 244 is connected to the controlled end of the power circuit 242.

[0079] Driver control circuit 244 controls the on / off switching of the switches in power circuit 242, enabling power circuit 242 to pump up the input ultra-low voltage to a high voltage. Power circuit 242 can utilize a Boost converter or other high-gain boost converter. Driver control circuit 244 can utilize an MSP430 series ultra-low-power control chip and its peripheral circuits.

[0080] Exemplarily, the drive control circuit 244 is powered by the second-highest voltage output by the startup module 6. In another exemplary embodiment, the drive control circuit 244 may also be powered by the high voltage output by the power circuit 242. When the voltage output by the power circuit 242 is higher than the voltage output by the startup module 6, the drive control circuit 244 is powered by the high voltage output by the power circuit 242; when the voltage output by the power circuit 242 is lower than the voltage output by the startup module 6, the drive control circuit 244 is powered by the second-highest voltage output by the startup module 6.

[0081] In this embodiment, a specific and feasible implementation method is provided for realizing the boost module.

[0082] In an exemplary embodiment, Figure 6 As shown, the boost module 24 further includes a diode D. The anode of the diode D is connected to the input end of the power circuit 242 , and the cathode of the diode D is connected to the power supply end of the drive control circuit 244 .

[0083] For example, when the voltage output by the power circuit 242 is higher than the voltage output by the starting module 6, the diode D is passed, and the drive control circuit 244 is powered by the high voltage output by the power circuit 242; when the voltage output by the power circuit 242 is lower than the voltage output by the starting module 6, the diode D is cut off, and the drive control circuit 244 is powered by the second highest voltage output by the starting module 6.

[0084] In this embodiment, the diode, based on its unidirectional conduction characteristics, automatically selects the optimal power source to power the drive control circuit under varying voltage conditions. When the voltage output by the power circuit is higher than the voltage output by the startup module, the diode conducts, allowing the high voltage from the power circuit to power the drive control circuit. Conversely, when the voltage output by the power circuit is lower than the voltage output by the startup module, the diode turns off, preventing reverse current flow. At this point, the drive control circuit is powered by the next-highest voltage provided by the startup module.

[0085] In an exemplary embodiment, Figure 7 As shown, the DC transmission line pressure difference energy harvesting system also includes a lithium battery charge and discharge management module 8. The input end of the lithium battery charge and discharge management module 8 is connected to the output end of the pressure difference energy harvesting module 2, and the output end of the lithium battery charge and discharge management module 8 is used to connect to the monitoring device 300.

[0086] For example, when the power output by the pressure difference energy collection module 2 is greater than the power required for the monitoring device 300 to operate, the remaining power is stored in the lithium battery charge and discharge management module 8 to store excess energy in the DC transmission line pressure difference energy extraction system; when the power output by the pressure difference energy collection module 2 cannot meet the power required for the monitoring device 300 to operate, the lithium battery charge and discharge management module 8 supplies energy to the monitoring device 300.

[0087] In this embodiment, by providing a lithium battery charge and discharge management module, when the output power of the pressure differential energy collection module exceeds the power required by the monitoring device, the excess energy is stored, avoiding energy waste. If the output power is insufficient to meet the monitoring device's needs, the lithium battery charge and discharge management module can provide the required energy to ensure continuous operation of the monitoring device.

[0088] In an exemplary embodiment, Figure 7 As shown, the lithium battery charge and discharge management module 8 includes a charging circuit 82, a lithium battery 84, and a discharging circuit 86. The input of the charging circuit 82 is connected to the output of the pressure difference energy harvesting module 2; the input of the lithium battery 84 is connected to the output of the charging circuit 82; the input of the discharging circuit 86 is connected to the output of the lithium battery 84, and the output of the discharging circuit 86 is connected to the monitoring device 300.

[0089] Among them, such as Figure 8 As shown, the charging circuit 82 can be composed of a TP4056 chip and its peripheral circuits to manage the charging of the lithium battery 84. The discharging circuit 86 can be composed of a PW3130 chip and its peripheral circuits and a TX4401 chip and its peripheral circuits to protect the lithium battery 84 from discharge and convert the voltage of the lithium battery 84 to meet the voltage requirements of the monitoring device 300.

[0090] For example, when the power output by the pressure difference energy collection module 2 is greater than the power required for the monitoring device 300 to operate, the remaining power is stored in the lithium battery 84, that is, the high voltage output by the pressure difference energy collection module 2 charges the lithium battery 84 through the charging circuit 82; when the power output by the pressure difference energy collection module 2 cannot meet the power required for the monitoring device 300 to operate, the lithium battery 84 supplies energy to the monitoring device 300 through the discharge circuit 86.

[0091] In an exemplary embodiment, the present application further provides a direct current (DC) power transmission system, comprising a DC transmission line, a monitoring device, and the DC transmission line voltage differential energy harvesting system of the above-described embodiment. The monitoring device is disposed on the DC transmission line and is configured to monitor the DC transmission line.

[0092] In an exemplary embodiment, Figure 9 As shown in the figure, the stabilization module can be composed of the TX4401 chip and its peripheral circuits, where V2 is the high voltage output by the pressure difference energy harvesting module. The stabilization module is used to convert the high voltage output by the pressure difference energy harvesting module into a stable voltage to meet the voltage requirements of the monitoring equipment.

[0093] In the description of this specification, reference to the terms "some embodiments" or "other embodiments" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example.

[0094] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0095] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A DC transmission line voltage difference energy harvesting system, characterized in that: The DC transmission line voltage difference energy acquisition system includes: A pressure difference energy collection module, wherein the input end of the pressure difference energy collection module is used to connect to a DC transmission line, and the pressure difference energy collection module is used to convert the pressure difference of the DC transmission line into a supply voltage for a monitoring device of the DC transmission line; A voltage stabilizing module, wherein the input end of the voltage stabilizing module is connected to the output end of the pressure difference energy collection module, and the output end of the voltage stabilizing module is used to connect to the monitoring device; A starting module, wherein the input end of the starting module is used to connect to the DC transmission line, the output end of the starting module is connected to the power supply end of the pressure difference energy harvesting module, and the starting module is used to convert the voltage difference on the DC transmission line into a starting voltage for the pressure difference energy harvesting module; The starting voltage of the starting module is lower than the starting voltage of the pressure difference energy harvesting module; Wherein, the startup module includes: a first energy storage filter capacitor, wherein an input end of the first energy storage filter capacitor is used to connect to the DC transmission line; a boost circuit, wherein an input end of the boost circuit is connected to an output end of the first energy storage filter capacitor; an energy storage capacitor, wherein an input end of the energy storage capacitor is connected to an output end of the boost circuit; A DC-DC conversion circuit, wherein the input end of the DC-DC conversion circuit is connected to the output end of the energy storage capacitor, and the output end of the DC-DC conversion circuit is connected to the power supply end of the pressure difference energy harvesting module; The power supply end of the pressure difference energy collection module is also connected to the output end of the pressure difference energy collection module, and the starting module further includes: a power supply control circuit, wherein a first input terminal of the power supply control circuit is connected to an output terminal of the pressure difference energy harvesting module, and a control terminal of the power supply control circuit is connected to a controlled terminal of the DC-DC conversion circuit; The power supply control circuit is used to obtain the output voltage of the pressure difference energy collection module, and control the DC-DC conversion circuit to stop working when the output voltage of the pressure difference energy collection module is greater than or equal to a preset threshold.

2. The DC transmission line voltage difference energy harvesting system according to claim 1, characterized in that: The second input terminal of the power supply control circuit is connected to the output terminal of the energy storage capacitor; The power supply control circuit is further configured to obtain the voltage of the energy storage capacitor and control the DC-DC conversion circuit to operate when the voltage of the energy storage capacitor is greater than or equal to the preset threshold.

3. The DC transmission line voltage difference energy harvesting system according to any one of claims 1-2, characterized in that: The pressure difference energy collection module includes: a second energy storage filter capacitor, wherein an input end of the second energy storage filter capacitor is used to connect to the DC transmission line; A boost module, wherein the input end of the boost module is connected to the output end of the second energy storage filter capacitor, the output end of the boost module is used to connect to the monitoring device, and the power supply end of the boost module is connected to the output end of the starting module.

4. The DC transmission line voltage difference energy harvesting system according to claim 3, characterized in that: The boost module comprises: a power circuit, wherein an input end of the power circuit is connected to an output end of the second energy storage filter capacitor, and an output end of the power circuit is used to connect to the monitoring device; A driving control circuit, wherein a power supply end of the driving control circuit is connected to the output end of the starting module, and a control end of the driving control circuit is connected to the controlled end of the power circuit.

5. The DC transmission line voltage difference energy harvesting system according to claim 4, characterized in that: The boost module further includes: A diode, wherein the anode of the diode is connected to the input end of the power circuit, and the cathode of the diode is connected to the power supply end of the drive control circuit.

6. The DC transmission line voltage difference energy harvesting system according to claim 1, characterized in that: The DC transmission line voltage difference energy acquisition system further includes: A lithium battery charge and discharge management module, wherein the input end of the lithium battery charge and discharge management module is connected to the output end of the pressure difference energy collection module, and the output end of the lithium battery charge and discharge management module is used to connect to the monitoring device.

7. The DC transmission line voltage difference energy harvesting system according to claim 6, characterized in that: The lithium battery charge and discharge management module includes: a charging circuit, wherein an input end of the charging circuit is connected to an output end of the pressure difference energy harvesting module; A lithium battery, wherein the input end of the lithium battery is connected to the output end of the charging circuit; A discharge circuit, wherein the input end of the discharge circuit is connected to the output end of the lithium battery, and the output end of the discharge circuit is used to connect to the monitoring device.

8. A direct current transmission system, characterized in that: The direct current transmission system comprises: DC transmission lines; A monitoring device, the monitoring device being arranged on the DC transmission line and being used to monitor the DC transmission line; And the DC transmission line voltage difference energy harvesting system according to any one of claims 1 to 7.

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