10kV capacitor voltage-dividing power-taking device and regulation and control method

Abstract

The invention relates to a 10kV capacitance voltage-dividing power taking device and a regulation and control method, and belongs to the technical field of power system functions, the 10kV capacitance voltage-dividing power taking device comprises a voltage acquisition device, an overvoltage protection device, a voltage conversion device and a control device, the voltage acquisition device is formed by connecting a capacitor and a transformer in series, one end of the capacitor is externally connected with a high-voltage line, and the other end of the capacitor is connected with the high-voltage end of the transformer; the low-voltage end of the transformer is sequentially connected with an overvoltage protection device, a voltage conversion device and control equipment in parallel. According to the invention, the energy utilization efficiency is improved, and the integrity and reliability of equipment are improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of power system functions, and particularly relates to a 10kV capacitor voltage division power taking device and a regulation and control method. BACKGROUND

[0002] With the development of smart grid, a large number of monitoring devices will be installed on the transmission line, and stable and reliable power supply is the key to ensure the effective operation of the monitoring device. However, the existing power supply has many shortcomings, for example: 1. Due to the long transmission distance, the line is in a harsh environment, and the operating conditions are severe, so the conventional 220V AC power supply cannot be easily obtained many times; 2. Solar power supply is easily affected by the environment and cannot provide continuous and reliable power supply; 3. CVT power taking is less distributed on the transmission line, and the volume is large; 4. The CT power taking is affected by the current on the transmission line, and for different regions and different time periods of the power grid load, the current on the transmission line is unstable, which leads to unstable power supply. The above-mentioned power supply methods have the problems of low reliability, high maintenance cost, etc., therefore, the efficient and reliable power supply of the on-line monitoring device of the transmission line has become a problem to be solved at present.

[0003] The capacitor voltage division power taking method uses a capacitor and a small power frequency transformer to divide the voltage, thereby providing a stable power supply for the load. However, due to the limitation of the power taking current and the large energy conversion loss, the device has low power taking efficiency. In addition, the primary and secondary voltages of the transformer are greatly affected by the load, and the working voltage of the transformer is limited in practice, therefore, efficient and stable power supply is crucial. SUMMARY

[0004] The present application aims to provide a 10kV capacitor voltage division power taking device and a regulation and control method to solve the technical problems of low power taking efficiency and output power affected by the load of the 10kV capacitor voltage division power taking device.

[0005] To achieve the above-mentioned purpose, the specific technical solutions of the present application are as follows: A 10kV capacitor voltage division power taking device, comprising a voltage acquisition device, an overvoltage protection device, a voltage conversion device and a control device, which are connected in series by a capacitor and a transformer, one end of the capacitor is connected to a high-voltage line, the other end is connected to the high-voltage end of the transformer, and the low-voltage end of the transformer is connected in parallel to the overvoltage protection device, the voltage conversion device and the control device in sequence.

[0006] Further, the overvoltage protection device comprises a transient suppression diode, a field effect transistor and / or a self-resetting fuse connected in series.

[0007] Further, the voltage conversion device comprises a rectifier module and a voltage stabilizing module connected in parallel between the overvoltage protection device and the control device in sequence, wherein the rectifier module is an AC / DC converter and uses a maximum power tracking (MPPT) technology.

[0008] Further, the control device is provided with a dynamic modulation mechanism.

[0009] Further, the capacitor has a capacitance value ranging from 1000 to 5000 pF, and under the premise that the power taking current is less than 10 mA, the capacitor is connected in series with a transformer to form a voltage acquisition device, and the voltage acquisition device is a voltage divider; the primary side of the transformer has a rated voltage ranging from 1000 to 4000 V AC, and the secondary side has a rated voltage ranging from 3 to 300 V AC.

[0010] Further, the capacitor has a capacitance value satisfying the following condition: C1≤5.5nF Wherein, C1 is the high-voltage power taking capacitance value.

[0011] Further, the AC / DC converter is a bridge rectifier circuit.

[0012] The application also provides a 10kV capacitor voltage division power taking regulation method, which adopts the 10kV capacitor voltage division power taking device described above for voltage division power taking, and has the following steps: Firstly, power is taken from a high-voltage line through the voltage acquisition device and converted into a lower AC voltage; Secondly, the overvoltage protection device is used to suppress overvoltage impact; Thirdly, the voltage conversion device is used in combination with the maximum power tracking (MPPT) technology to efficiently convert AC power into stable DC power; Fourthly, the dynamic modulation mechanism is used to adjust the equivalent load and output power in real time, so as to ensure stable output power under various load conditions.

[0013] Compared with the prior art, the application has the following advantages: 1. Through reasonable design and parameter selection of the voltage acquisition device, the overvoltage protection device and the voltage conversion device, and in combination with the maximum power tracking (MPPT) technology, the energy utilization efficiency is improved.

[0014] 2. Through the voltage stabilizing module and the dynamic modulation mechanism, constant voltage output of the capacitor power taking device is realized, so that the power taking device can stably and reliably provide power for the control device within the voltage ±10% fluctuation range of the power transmission line and under various load conditions (including light load or no load).

[0015] 3. Through thermal management, electromagnetic compatibility and modular design, the overall performance and reliability of the device are improved.

[0016] 4. Overvoltage protection better ensures the safety of the circuit in the event of voltage surges or transient events. Attached Figure Description

[0017] Fig. 1 This is a schematic block diagram of the power extraction device of the present invention; Fig. 2 This is a schematic diagram of the circuit principle of the power supply device of the present invention; The markings in the diagram are as follows: 1. Voltage acquisition device; 11. Capacitor; 12. Transformer; 2. Overvoltage protection device; 3. Voltage conversion device; 31. Rectifier module; 32. Voltage regulator module; 4. Control equipment. Detailed Implementation

[0018] To better understand the purpose, structure, and function of this invention, the following detailed description of a 10kV capacitor voltage divider power extraction device and its control method is provided in conjunction with the accompanying drawings.

[0019] like Figs. 1-2 As shown, the 10kV capacitor voltage divider power extraction device of the present invention includes a voltage acquisition device, an overvoltage protection device, a voltage conversion device, and a control device. The voltage acquisition device is a voltage divider, which is composed of a capacitor and a transformer connected in series. In this embodiment, the capacitor is a high-voltage power extraction capacitor, and the transformer is a low-power power frequency transformer. One end of the capacitor is connected to a high-voltage line, and the other end is connected to the high-voltage end of the transformer. The voltage acquisition device can convert high-voltage AC power into a lower AC voltage, which is used by the power extraction device to obtain a stable AC voltage from a high potential in the power grid. The overvoltage protection device, the voltage conversion device, and the control device are connected in parallel to the low-voltage end of the transformer.

[0020] Overvoltage protection devices can be installed at the front or rear end of the voltage acquisition device, or simultaneously at both ends. They include one or more of the following: transient suppression diodes, field-effect transistors, or self-resetting fuses connected in series. They can protect the power-generating device from overvoltage.

[0021] The voltage conversion device includes a rectifier module and a voltage regulator module, which are connected in parallel between the overvoltage protection device and the control equipment. In this embodiment, an AC / DC converter is used as the rectifier module, which converts AC voltage into a stable DC voltage and uses maximum power point tracking (MPPT) technology to maximize power output for use by the control equipment.

[0022] Furthermore, the control equipment is equipped with a dynamic modulation mechanism, which is achieved through dynamic reactive power compensation technology, enabling the device to stably supply power to the control equipment under various load conditions, and achieving efficient and stable power output under various load conditions.

[0023] Further, the capacitor is used for voltage division of the power supply circuit, and the capacitance value ranges from 1000 to 5000 pF, and a voltage divider is formed in series with the transformer under the condition that the power supply current is less than 10 mA; the transformer is used for voltage conversion and potential isolation of the high-voltage power system, and the rated voltage of the primary side ranges from 1000 to 4000 V AC, and the rated voltage of the secondary side ranges from 3 to 300 V AC.

[0024] Further, the high-voltage power supply capacitor value C1 is less than or equal to 5.5 nF (wherein C1 is the high-voltage power supply capacitor value).

[0025] The AC / DC converter for the rectifier module is used to convert AC into DC, and the preferred bridge rectifier circuit; the voltage stabilizing module is used to ensure stable power output when the voltage / load of the high-voltage power supply end changes suddenly. The dynamic modulation mechanism is realized by dynamic reactive power compensation technology, so that the device can stably supply power to the control equipment under various load conditions.

[0026] The application is applied to the regulation and control method of the 10kV capacitor voltage division power supply device, which comprises the following steps: Firstly, the voltage acquisition device is used to supply power from the high-voltage line and convert it into lower AC voltage, specifically: the capacitor generates stable milliamperes AC current through the high potential of the power grid, and the transformer converts the high-voltage small current into low-voltage large current; Secondly, the overvoltage protection device is used to suppress overvoltage impact; Thirdly, the voltage conversion device is used in combination with the maximum power tracking (MPPT) technology to efficiently convert AC into stable DC, specifically: the rectifier module is used to regulate the waveform of the transformer secondary side, convert AC into DC, and provide usable DC for subsequent loads; the voltage stabilizing module is used to improve the stability of the power supply device, stabilize the voltage of the power supply circuit when the load changes and the high-voltage power supply voltage fluctuates, and improve the quality of voltage output; Fourthly, the dynamic modulation mechanism is used to adjust the equivalent load and output power in real time, so as to ensure stable power output under various load conditions.

[0027] Performance test one The 10kV capacitor voltage division power supply device is used for a 10kV vacuum circuit breaker capacitor voltage division power supply device, which is installed between a 10kV line and the ground and is used for power supply of a 10kV circuit breaker.

[0028] The high-voltage power supply capacitor is a 3600 pF high-voltage capacitor. The primary and secondary voltages of the transformer are 2300 V AC / 220 V AC. The overvoltage protection module uses a bidirectional TVS tube. The rectification module uses bridge rectification, the module supports a maximum reverse working voltage of 600V, an average forward current of 1A, and has a low forward on-voltage.

[0029] The voltage stabilization module uses a DC-DC conversion chip, which has a wide input voltage range of 4.5 to 28V and an adjustable output voltage of a maximum of 28V, a maximum output continuous current of up to 3A, supports a fixed switching frequency of up to 400kHz, and has a maximum efficiency of up to 95%.

[0030] Performance test two The 10kV capacitor voltage division power taking device is used for a 10kV power transmission line monitoring system power taking device, and is installed between a 10kV power transmission line and the ground.

[0031] The high-voltage power taking capacitor is 5000pF; The primary and secondary rated voltage of the transformer is AC 2300V / 220V; The overvoltage protection module uses a TSS device; The rectification module uses bridge rectification; The voltage stabilization module uses a DC-DC conversion chip, which has a wide input voltage range of 5 to 30V and an adjustable output of 5 to 24V, and a maximum output continuous current of up to 3.5A.

[0032] Performance test three The 10kV capacitor voltage division power taking device is used for a 10kV pole-mounted switch capacitor voltage division power taking device, is installed between a 10kV line and the ground, and is used for power supply of a 10kV pole-mounted switch and an FTU thereof.

[0033] The high-voltage power taking capacitor is a high-voltage capacitor of 2400pF; The primary and secondary rated voltage of the transformer is AC 1200V / 24V.

[0034] The overvoltage protection module is a TSS device; The voltage stabilization module uses a DC-DC conversion chip, which has a wide input voltage range of 4 to 25V, an output voltage of 24V fixed, and a maximum output continuous current of 4A.

[0035] The 10kV capacitor voltage division power taking device can stably operate under different load conditions, and the application provides a 10kV capacitor voltage division power taking device and a regulation and control method, which first takes power from a high-voltage side through a voltage division capacitor, and supplies power to a load through a transformer, a rectification module and a voltage stabilization module. Combined with the maximum power point tracking technology, the maximum power output is realized. Dynamic reactive power compensation is used, so that the device can stably supply power to control equipment under various load conditions, and realize efficient and stable power output.

[0036] It is to be understood that the present application is described by way of example only, and that modifications or alterations can be made to the features and embodiments described without departing from the spirit and scope of the application. In addition, modifications can be made to the features and embodiments described to accommodate specific situations and materials without departing from the spirit and scope of the application. Accordingly, the application is not limited to the specific embodiments disclosed herein, but rather, the scope of the application includes all embodiments falling within the scope of the claims.

Claims

1. A 10kV capacitor voltage divider power extraction device, characterized in that, It includes a voltage acquisition device, an overvoltage protection device, a voltage conversion device, and a control device. It consists of a capacitor and a transformer connected in series. One end of the capacitor is connected to a high-voltage line, and the other end is connected to the high-voltage end of the transformer. The low-voltage end of the transformer is connected in parallel with the overvoltage protection device, the voltage conversion device, and the control device.

2. The 10kV capacitor voltage divider power extraction device according to claim 1, characterized in that, The overvoltage protection device includes a transient suppression diode, a field-effect transistor, and / or a resettable fuse connected in series.

3. The 10kV capacitor voltage divider power extraction device according to claim 1, characterized in that, The voltage conversion device includes a rectifier module and a voltage regulator module connected in parallel between the overvoltage protection device and the control device. The rectifier module is an AC / DC converter and uses maximum power point tracking (MPPT) technology.

4. The 10kV capacitor voltage divider power extraction device according to claim 1, characterized in that, The control device is equipped with a dynamic modulation mechanism.

5. The 10kV capacitor voltage divider power extraction device according to claim 1, characterized in that, The capacitance value of the capacitor is in the range of 1000~5000pF. Under the premise that the current draw is less than 10mA, it is connected in series with the transformer to form a voltage acquisition device, which is a voltage divider. The rated voltage range of the primary side of the transformer is AC 1000~4000V, and the rated voltage range of the secondary side is AC 3~300V.

6. The 10kV capacitor voltage divider power extraction device according to claim 5, characterized in that, The capacitance value of the capacitor satisfies the following condition: C1≤5.5nF Where C1 is the value of the high-voltage power extraction capacitor.

7. The 10kV capacitor voltage divider power extraction device according to claim 3, characterized in that, The AC / DC converter is a bridge rectifier circuit.

8. A 10kV capacitor voltage divider power extraction method, comprising using the 10kV capacitor voltage divider power extraction device according to any one of claims 1 to 7 for voltage divider power extraction, characterized in that, It includes the following steps: The first step is to draw power from the high-voltage line using the voltage acquisition device and convert it to a lower AC voltage; The second step is to use the overvoltage protection device to suppress overvoltage surges. The third step involves using the voltage conversion device, combined with maximum power point tracking (MPPT) technology, to efficiently convert AC power into stable DC power. Fourth step: Through the aforementioned dynamic modulation mechanism, the equivalent load and output power are adjusted in real time to ensure stable output power under various load conditions.

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