Direct-current power transmission line differential pressure energy taking system and direct-current power transmission system

Abstract

The invention relates to a direct-current power transmission line voltage difference energy taking system and a direct-current power transmission system. The direct-current power transmission line voltage difference energy taking system comprises a voltage difference energy collecting module, a voltage stabilizing module and a starting module. The input end of the voltage difference energy collection module is used for being connected with a direct-current power transmission line. The voltage difference energy collection module is used for converting the voltage difference of the direct-current power transmission line into power supply voltage of monitoring equipment of the direct-current power transmission line. The input end of the voltage stabilization module is connected with the output end of the differential pressure energy collection module, and the output end of the voltage stabilization module is used for being connected with monitoring equipment; the input end of the starting module is used for being connected with a direct-current power transmission line, the output end of the starting module is connected with the power supply end of the differential pressure energy collecting module, and the starting module is used for converting differential pressure on the direct-current power transmission line into starting voltage of the differential pressure energy collecting module. The starting voltage of the starting module is smaller than the starting voltage of the differential pressure energy collection module. The direct-current power transmission line differential pressure energy taking system can take power from the direct-current power transmission line stably and reliably.

Description

Technical Field

[0001] The present application relates to the technical field of direct current transmission, and in particular to a direct current transmission line pressure difference energy extraction system and a direct current transmission system. Background Art

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

[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, and it is 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 acquisition system, the DC transmission line pressure difference energy acquisition 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 pressure difference of the DC transmission line into a power supply voltage of a monitoring device of the DC transmission line;

[0008] A voltage stabilizing module, 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 the monitoring device;

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

[0010] The startup voltage of the startup module is lower than the startup voltage of the voltage 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] 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 collection module.

[0016] In one embodiment, 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 start-up 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 collection 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 of the embodiments, 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 also used to obtain the voltage of the energy storage capacitor, and control the DC-DC conversion circuit to work when the voltage of the energy storage capacitor is greater than or equal to a preset threshold.

[0021] In one of the embodiments, 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, 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 the monitoring device, and the power supply end of the boost module is connected to the output end of the start module.

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

[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 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 extraction system further includes:

[0030] 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 a monitoring device.

[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 an input terminal of the lithium battery is connected to an output terminal of a charging circuit;

[0034] 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 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 arranged 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 harvesting system in the above embodiment.

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

[0040] By setting up the startup module, it is possible to obtain energy from the DC transmission line itself to complete the self-start of the DC transmission line voltage difference energy acquisition system, thereby providing power for the monitoring equipment and reducing dependence on external energy. It works under the condition of small voltage difference of the transmission line, has strong adaptability, and can provide stable power supply for the monitoring equipment even in the case of voltage fluctuations or line load changes. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. 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 It is a structural schematic diagram of a DC transmission line voltage difference energy extraction system in one embodiment;

[0043] Figure 2 is a schematic diagram of the structure of a startup module in an embodiment;

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

[0045] Figure 4 It is a 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 waveform of APX809-46SAG-7 chip in one embodiment;

[0047] Figure 6 is a schematic structural diagram of a pressure difference energy harvesting module in an embodiment;

[0048] Figure 7 It is a structural schematic diagram of a DC transmission line voltage difference energy extraction system in another embodiment;

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

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

[0051] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is 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 belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0053] It is understood that the terms "first", "second", etc. used in this application may be used herein 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, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are 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 the connected circuits, modules, units, etc. have electrical signals or data transmission between each other.

[0055] It can be understood that “at least one” means one or more, “plurality” means two or more, and “at least a portion of an element” means a part or all of an element.

[0056] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" etc. specify the presence of stated features, wholes, steps, operations, components, parts or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, 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 collection module 2, a voltage stabilizing module 4 and a starting module 6. The input end of the pressure difference energy collection module 2 is used to connect the DC transmission line 100, and the pressure difference energy collection 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 collection module 2, and the output end of the voltage stabilizing module 4 is used to connect the monitoring device 300; the input end of the starting module 6 is used to connect 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 collection 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 collection module 2; the starting voltage of the starting module 6 is less than the starting voltage of the pressure difference energy collection 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 start-up of the DC transmission line pressure difference energy acquisition 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 equipment damage or unstable operation caused by voltage fluctuations. It should be noted that the starting voltage of the starting module 6 is less than the starting voltage of the pressure difference energy collection module 2, and 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 section of DC transmission line 100 with a resistivity of ρ and a length of L, it has a resistance value of R=ρL. According to Ohm's law, when a current I flows through the line, the voltage difference generated is V=IρL. Since the resistivity ρ is very small and the length L value is not large, the voltage difference V generated is generally ultra-low. Although the voltage difference V generated is ultra-low, since the current I on the DC transmission line 100 is very large and relatively stable in a short time, this ultra-low voltage difference V still contains a certain amount of energy. The pressure difference energy collection module 2 collects the ultra-low pressure difference at both ends of a section of DC transmission line 100 in real time, and boosts the ultra-low pressure difference to a high voltage with high power, and then converts the high voltage output by the pressure difference energy collection module 2 into a stable voltage through the voltage stabilizing module 4, and supplies power to the electronic loads such as the monitoring device 300 (such as a sensor) on the DC transmission line 100. Since the power of the power device inside the pressure difference energy collection module 2 is large and the starting voltage threshold is high, the power supply voltage and power provided to the pressure difference energy collection module 2 need to be high enough to drive these power devices to work. 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 above-mentioned DC transmission line voltage difference energy acquisition system, by setting a starting module, can obtain energy from the DC transmission line itself to complete the self-starting of the DC transmission line voltage difference energy acquisition system, thereby providing power for the monitoring equipment and reducing dependence on external energy. It works when the voltage difference of the transmission line is small, has strong adaptability, and can provide a stable power supply for the monitoring equipment even in the case of voltage fluctuations or line load changes.

[0061] In an exemplary embodiment, Figure 2As shown, the start-up 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 collection 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 collection module is reached when the pressure difference energy collection module is subsequently powered.

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

[0065] Among them, 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 collection 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 charges 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, so that the DC-DC conversion circuit 66 starts to work, and the energy stored in the energy storage capacitor C5 provides a starting voltage for the pressure difference energy collection module 2 through the DC-DC conversion circuit 66. However, when it is detected that the output voltage of the pressure difference energy collection module 2 is greater than the maximum charging voltage V1max, it means that the output voltage of the pressure difference energy collection module 2 can meet the voltage required to drive the power devices in itself to work normally. Therefore, the reset pin of the APX809-46SAG-7 chip can output a low level at this time to turn off the DC-DC conversion circuit 66 to reduce power consumption and realize self-power supply through the pressure difference energy collection 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 for starting the pressure difference energy collection module 2 is:

[0068]

[0069] According to the selection of different chips of the pressure difference energy collection 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 terminal of the power supply control circuit 68 is connected to the output terminal 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 For example, the reset pin of the APX809-46SAG-7 chip will output a high level to enable the DC-DC converter circuit 66 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, the DC-DC conversion circuit 66 is turned off, 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 work 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 collection 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, the output end of the boost module 24 is used to connect to the monitoring device 300, and the power supply end of the boost module 24 is connected to the output end of the start 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] Exemplarily, a connecting conductor and a connecting wire are used to lead the ultra-low voltage difference generated by a section of the DC transmission line 100 to both ends of the second energy storage filter capacitor 22, and the voltage difference on the DC transmission line 100 charges the second energy storage filter capacitor 22, so that the second energy storage filter capacitor 22 obtains an ultra-low voltage. The output end of the second energy storage filter capacitor 22 is connected to the input end of the boost module 24, and the boost module 24 converts the ultra-low voltage at both ends of 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 the monitoring device 300; the power supply end of the drive control circuit 244 is connected to the output end of the start module 6, and the control end of the drive control circuit 244 is connected to the controlled end of the power circuit 242.

[0079] The drive control circuit 244 is used to control the on and off of the switch tube in the power circuit 242, so that the power circuit 242 can pump the input ultra-low voltage to a high voltage. The power circuit 242 can use a Boost converter or other high-gain boost converter, and the drive control circuit 244 can be composed of an ultra-low power control chip of the MSP430 series and its peripheral circuits.

[0080] Exemplarily, the drive control circuit 244 is powered by the second highest voltage output by the start-up module 6. In an 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 start-up 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 start-up module 6, the drive control circuit 244 is powered by the second highest voltage output by the start-up 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. An anode of the diode D is connected to the input end of the power circuit 242 , and a cathode of the diode D is connected to the power supply end of the drive control circuit 244 .

[0083] Exemplarily, 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 driving 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 driving control circuit 244 is powered by the second highest voltage output by the starting module 6.

[0084] In this embodiment, by providing a diode, based on its unidirectional conduction characteristics, the best power supply can be automatically selected to power the drive control circuit under different voltage conditions. When the voltage output by the power circuit is higher than the voltage output by the startup module, the diode is turned on, allowing the high voltage of 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 is turned off to prevent reverse current from flowing, and the drive control circuit is powered by the second 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 collection module 2, and the output end of the lithium battery charge and discharge management module 8 is used to connect the monitoring device 300.

[0086] Exemplarily, 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 for the monitoring device 300.

[0087] In this embodiment, by setting up a lithium battery charge and discharge management module, when the output power of the pressure difference energy collection module is greater than the power required by the monitoring device, the excess energy is stored to avoid energy waste. When the output power is insufficient to meet the needs of the monitoring device, the lithium battery charge and discharge management module can provide the required energy to ensure the 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 end of the charging circuit 82 is connected to the output end of the pressure difference energy collection module 2; the input end of the lithium battery 84 is connected to the output end of the charging circuit 82; the input end of the discharging circuit 86 is connected to the output end of the lithium battery 84, and the output end of the discharging circuit 86 is used to connect the monitoring device 300.

[0089] Among them, Figure 8 As shown, the charging circuit 82 can be composed of a TP4056 chip and its peripheral circuits to implement charging management for 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 implement protection for the discharge of the lithium battery 84 and transform the voltage of the lithium battery 84 to meet the voltage requirement of the monitoring device 300.

[0090] Exemplarily, 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 also provides a direct current transmission system, which includes a direct current transmission line, a monitoring device, and the direct current transmission line voltage difference energy extraction system in the above embodiment. The monitoring device is arranged on the direct current transmission line, and the monitoring device is used to monitor the direct current transmission line.

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

[0093] In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", etc. 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 description of the above terms does not necessarily refer to the same embodiment or example.

[0094] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described 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 only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A DC power transmission line voltage difference energy extraction system, characterized in that: The DC transmission line voltage difference energy acquisition system comprises: 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 of 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 a DC transmission line, the output end of the starting module is connected to the power supply end of the pressure difference energy collection module, and the starting module is used to convert the pressure difference on the DC transmission line into a starting voltage of the pressure difference energy collection module; The starting voltage of the starting module is lower than the starting voltage of the pressure difference energy collection module.

2. The DC power transmission line voltage difference energy extraction system according to claim 1, characterized in that: 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 collection module.

3. The DC power transmission line voltage difference energy extraction system according to claim 2, characterized in that: 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 end of the power supply control circuit is connected to an output end of the pressure difference energy collection module, and a control end of the power supply control circuit is connected to a controlled end 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.

4. The DC power transmission line voltage difference energy extraction system according to claim 3, 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 used 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.

5. The DC power transmission line pressure difference energy harvesting system according to any one of claims 1 to 4, characterized in that: The pressure difference energy collection module comprises: 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.

6. The DC power transmission line voltage difference energy extraction system according to claim 5, 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 an output end of the starting module, and a control end of the driving control circuit is connected to a controlled end of the power circuit.

7. The DC power transmission line voltage difference energy extraction system according to claim 6, characterized in that: The boost module further comprises: 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.

8. The DC power 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.

9. The DC power transmission line voltage difference energy extraction system according to claim 8, 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 collection module; A lithium battery, wherein an input terminal of the lithium battery is connected to an output terminal 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.

10. A direct current transmission system, characterized in that: The DC transmission system comprises: DC transmission lines; A monitoring device, the monitoring device is arranged on the DC transmission line, and the monitoring device is used to monitor the DC transmission line; And a direct current transmission line pressure difference energy harvesting system as described in any one of claims 1 to 9.

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