A closed-loop regulated high-voltage power supply and method of use thereof

Abstract

This invention discloses a closed-loop regulated high-voltage power supply and its usage method, belonging to the field of high-voltage electrical technology. The power supply includes a power module, an energy storage capacitor module, an electrode module, an electromagnetic drive module, and a microcontroller control module. The power module converts DC power into high-frequency AC power, which is then boosted and rectified before outputting a high-voltage DC voltage. The energy storage capacitor module stores electrical energy. The electromagnetic drive module adjusts the electrode spacing via an electromagnetic coil. The microcontroller control module samples the capacitor voltage in real time and adjusts the PWM duty cycle to stabilize the capacitor voltage within a set range. The usage method includes initialization, voltage conversion, capacitor charging, voltage regulation control, electrode adjustment, and discharge steps. This invention features high voltage stability and high electrode spacing adjustment accuracy.

Description

Technical Field

[0001] This invention relates to the field of high-voltage electrical technology, specifically to a closed-loop regulated high-voltage power supply and its usage method. Background Technology

[0002] Partial discharge is an important research method for studying the insulation characteristics of high-voltage equipment, and it is widely used in the detection of high-voltage power systems, electronic equipment, and insulating materials. Most existing partial discharge experimental setups use direct power supply and trigger discharge by adjusting the electrode spacing. However, the stability of the power supply has always plagued the accuracy of the experiment, because factors such as power fluctuations, environmental interference, and load changes can all lead to unstable electrode voltages, making the experimental results of partial discharge unrepeatable or containing significant deviations.

[0003] Furthermore, traditional methods of adjusting electrode spacing mostly rely on manual or mechanical adjustments, which are characterized by low precision and cumbersome operation. They also fail to accurately control the electric field strength between the electrodes, leading to unstable or inaccurate discharge voltages. To improve the stability and accuracy of experiments, a device capable of providing a stable voltage output and precisely adjusting the electrode spacing is urgently needed. Summary of the Invention

[0004] The purpose of this invention is to provide a sludge drying device, comprising a mains power supply, a rectifier and filter circuit, a DC-DC converter, a DSP processor, a microcontroller control system, a PWM amplifier circuit, a full-bridge inverter circuit, and electrodes. The mains power supply provides power to the sludge drying device. The rectifier and filter circuit converts the mains power into DC power. The DC-DC converter, connected to the rectifier and filter circuit, transforms and stabilizes the voltage. The DSP processor assesses the sludge state based on signals from a humidity sensor and generates pulse signals with corresponding pulse widths according to the sludge state. The microcontroller control system generates control signals. The PWM amplifier circuit amplifies the PWM waveform. The full-bridge inverter circuit, connected to the PWM amplifier circuit, converts the DC voltage into a bipolar pulse voltage to prevent electrode electrolytic corrosion. The electrodes, connected to the full-bridge inverter circuit, apply an alternating electric field to the sludge to accelerate moisture polarization migration.

[0005] Furthermore, the DC-DC converter employs a full-bridge LLC resonant converter to achieve wide voltage range regulation; the DSP processor dynamically tracks the optimal dry point through resistivity-frequency closed-loop optimization; the full-bridge inverter circuit consists of four sets of power switching transistors, which achieve DC-to-AC voltage conversion through alternating switching.

[0006] Furthermore, the frequency range of the bipolar pulse is 1kHz to 50kHz, and the amplitude range is 12V to 60V; the target resistivity of the drying device is greater than 200Ω·m, corresponding to a target humidity of 40%.

[0007] Furthermore, the method of using the sludge drying device is characterized by comprising the following steps:

[0008] Step S100: Place the sludge to be treated between the electrodes, ensuring good contact between the electrodes and the sludge;

[0009] Step S200: Start the device. The grid power is converted into DC power by the rectifier and filter circuit. The DC-DC converter transforms and regulates the voltage.

[0010] Step S300: The humidity sensor detects the humidity parameters of the sludge in real time and transmits the detection signal to the DSP processor;

[0011] Step S400: The DSP processor evaluates the sludge state based on the signal from the humidity sensor, dynamically tracks the optimal drying point through resistivity-frequency closed-loop optimization, and generates a pulse signal with a corresponding pulse width based on the evaluation results.

[0012] Step S500: The microcontroller control system receives instructions from the DSP processor and generates a PWM control signal;

[0013] Step S600: The PWM amplifier circuit amplifies the PWM signal to the required drive level;

[0014] Step S700: The full-bridge inverter circuit converts the DC voltage into a bipolar pulse voltage and outputs it to the electrodes;

[0015] Step S800: The electrodes generate an alternating electric field that acts on the sludge, accelerating the polarization and migration of water, thereby achieving sludge drying;

[0016] Step S900: Repeat steps S300 to S800 until the resistivity of the sludge is greater than 200 Ω·m and the corresponding moisture content reaches 40%, thus completing the drying process.

[0017] Furthermore, the resistivity-frequency closed-loop optimization in step S400 specifically includes: setting an initial frequency of 1kHz, continuously monitoring the resistivity and water content of the sludge, and when the resistivity is ≤200Ω·m or the water content is >40%, increasing the frequency in steps of 500Hz, waiting for 30 minutes after each increase, until the resistivity is >200Ω·m and the water content reaches 40%, and outputting the current frequency as the optimal drying frequency.

[0018] Furthermore, the frequency range of the bipolar pulse in step S700 is 1kHz to 50kHz, and the amplitude range is 12V to 60V.

[0019] Furthermore, when the resistivity of the sludge in step S900 is greater than 200 Ω·m and the corresponding humidity reaches 40%, the system automatically stops drying or maintains a heat preservation state.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] (1) The present invention uses a microcontroller to sample the capacitor voltage in real time and dynamically adjust the PWM duty cycle. When the capacitor voltage approaches the target value, the charging rate is gradually reduced and the trickle charging mode is entered, so that the capacitor voltage is stabilized within the set range. This effectively avoids the problem of voltage instability caused by power fluctuations when the traditional power supply is directly powered.

[0022] (2) The present invention uses electromagnetic drive to adjust the electrode spacing and precisely controls the position of the movable electrode through electromagnetic coil. Compared with the traditional manual adjustment method, it significantly improves the adjustment accuracy and operation efficiency, and ensures that the electrode conducts and discharges stably under the set voltage.

[0023] (3) By combining capacitor energy storage with closed-loop voltage regulation control, the present invention can still provide a stable voltage to the electrodes after the power supply is disconnected, thereby improving the repeatability and accuracy of partial discharge experiments.

[0024] The present invention will now be further described with reference to the accompanying drawings. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the system structure of a closed-loop regulated high-voltage power supply according to an embodiment of the present invention.

[0026] Figure 2 This is a structural diagram of a full-bridge inverter circuit according to an embodiment of the present invention.

[0027] Figure 3 This is a schematic diagram of the power supply circuit according to an embodiment of the present invention.

[0028] Figure 4 This is a schematic diagram of the electromagnetic drive module structure according to an embodiment of the present invention.

[0029] Figure 5 This is a schematic diagram of the electrode module in an embodiment of the present invention.

[0030] Figure 6 This is a circuit diagram of the microcontroller control module in an embodiment of the present invention. Detailed Implementation

[0031] Reference Figure 1 The closed-loop regulated high-voltage power supply in this embodiment mainly includes a power supply module, an energy storage capacitor module, an electrode module, an electromagnetic drive module, and a microcontroller control module.

[0032] Reference Figure 2 and Figure 3 The power module provides a stable DC voltage. It connects to a 24V DC power supply and converts the DC power to 15kHz high-frequency AC power via a full-bridge inverter circuit. Figure 2As shown, the full-bridge inverter circuit uses four high-frequency switching elements to convert DC power into high-frequency AC power through rapid switching and closing. This design results in high conversion efficiency and low energy loss. After passing through the inverter circuit, the high-frequency AC power is stepped up by a step-up transformer and further converted into DC power by a voltage doubler rectifier circuit. Figure 3 As shown, the voltage multiplier rectifier circuit adopts a six-stage voltage multiplier structure, using a combination of diodes and capacitors to progressively increase the amplitude of the AC current, ultimately outputting a 35kV DC high voltage. Figure 3 As shown, a protective resistor is connected in series between the power module and the energy storage capacitor module to limit the current during the charging process.

[0033] Reference Figure 6 The microcontroller control module uses an STM32F103C8T6 microcontroller, whose circuitry includes a crystal oscillator circuit, a reset circuit, and a power supply circuit. The microcontroller features PWM output, ADC sampling, and serial communication functions, responsible for real-time sampling of the capacitor voltage and adjusting the PWM duty cycle. The microcontroller samples the capacitor voltage in real time through the ADC module, converts the sampling results into digital signals for processing, and dynamically adjusts the PWM signal duty cycle based on the difference between the capacitor voltage and the target voltage, thereby regulating the charging rate. During the charging phase, when the capacitor voltage is low, the duty cycle is large, and the charging rate is high; as the capacitor voltage approaches the target value, the duty cycle gradually decreases, and the charging rate slows down, thus avoiding overcharging.

[0034] Reference Figure 4 The electromagnetic drive module includes an electromagnetic coil, an iron core, and a spring structure, used to drive the movable electrode to move and adjust the electrode spacing. When the electromagnetic coil is energized, it generates electromagnetic force, pushing the movable electrode to move axially, thus achieving precise adjustment of the electrode spacing. When the electromagnetic coil is energized, the movable electrode moves under the action of electromagnetic force; when the coil is de-energized, the electromagnet is demagnetized, and the movable electrode returns to its initial position under the action of the spring restoring force. The current of the electromagnetic coil is controlled by a microcontroller via a PWM signal, and the electrode spacing adjustment range is 0.1mm to 5mm, with an adjustment accuracy of 0.1mm.

[0035] Reference Figure 5 The electrode module includes fixed electrodes and movable electrodes. The fixed electrodes are fixed to the experimental platform by a bracket, while the movable electrodes are adjusted by an electromagnetic drive module. The voltage between the electrodes is supplied by an energy storage capacitor, and the electrode spacing is precisely adjusted by the electromagnetic drive module to ensure that the electrodes can stably conduct and discharge under the set voltage.

[0036] The energy storage capacitor module stores the energy supplied by the power source. The capacitors are metallized polypropylene film capacitors with capacitance ranging from 100nF to 500nF and a rated voltage of 35kV. In high-voltage experiments, the capacitors store the electrical energy output by the power source and continue to provide a stable voltage to the electrodes after the power is disconnected. When the capacitor voltage approaches the target value, the microcontroller control module adjusts the charging rate of the power source through the PWM duty cycle to prevent capacitor voltage overshoot. Specifically, when the capacitor voltage approaches 35kV, the PWM duty cycle gradually decreases, eventually entering a fine-tuning mode with a very small duty cycle, stabilizing the capacitor voltage within the range of 30kV±50V.

[0037] This invention also proposes a method for using a closed-loop regulated high-voltage power supply, comprising the following steps:

[0038] Step S100: The system is powered on and initialized. The microcontroller control module reads the preset parameters and sets the target voltage and current protection thresholds.

[0039] Step S200: The power module converts 24V DC power into 15kHz high-frequency AC power through a full-bridge inverter circuit. After being stepped up by a step-up transformer, it outputs 35kV DC high voltage through a six-stage voltage multiplier rectifier circuit.

[0040] Step S300: The energy storage capacitor module starts charging. The microcontroller control module samples the capacitor voltage in real time through the ADC and dynamically adjusts the PWM duty cycle according to the difference between the capacitor voltage and the target voltage to control the charging rate.

[0041] Step S400: When the capacitor voltage approaches the target value, the microcontroller control module gradually reduces the PWM duty cycle, successively decreasing from a high duty cycle to a low duty cycle, and finally enters trickle charging mode to stabilize the capacitor voltage within the set range.

[0042] Step S500: The electromagnetic drive module adjusts the electrode spacing according to the instruction, controls the current intensity of the electromagnetic coil through the PWM signal, and the electromagnetic force pushes the movable electrode to move along the axis to achieve precise adjustment of the electrode spacing.

[0043] Step S600: When the electrode spacing reaches the set value, the system enters the discharge mode, and the energy storage capacitor provides a stable voltage to the electrodes.

[0044] Step S700: Repeat steps S300 to S600 until a stop command is received.

[0045] The system also features multiple safety protection mechanisms: when the capacitor voltage exceeds a set threshold, the microcontroller will automatically stop charging to prevent overcharging; when the current exceeds a set threshold, the system will automatically shut down the power to avoid circuit overload; when the system temperature is too high, the system will automatically adjust the power supply or shut down the power; and when the power is off, the system will automatically reduce the capacitor voltage to a safe value to prevent high voltage residue.

Claims

1. A closed-loop regulated high-voltage power supply, characterized in that, include: The power module uses DC power input, which is converted into high-frequency AC power through a full-bridge inverter circuit. After being stepped up by a step-up transformer, it outputs high-voltage DC power through a voltage doubler rectifier circuit. An energy storage capacitor module is connected in parallel with the output terminal of the power supply module to store electrical energy; An electrode module includes fixed electrodes and movable electrodes, and the voltage between the electrodes is supplied by an energy storage capacitor. An electromagnetic drive module, comprising an electromagnetic coil, an iron core, and a spring structure, is used to drive the movable electrodes to move in order to adjust the electrode spacing. The microcontroller control module is used to sample the capacitor voltage in real time and control the charging rate by adjusting the PWM duty cycle, so that the capacitor voltage is stabilized within the set range.

2. The closed-loop regulated high-voltage power supply according to claim 1, characterized in that, The voltage multiplier rectifier circuit is a six-stage voltage multiplier circuit, which achieves voltage multiplication through a series and parallel combination of multiple diodes and capacitors.

3. The closed-loop regulated high-voltage power supply according to claim 1, characterized in that, The energy storage capacitor module includes metallized polypropylene film capacitors with a capacitance of 100nF to 500nF and a rated voltage of 35kV.

4. The closed-loop regulated high-voltage power supply according to claim 1, characterized in that, A protective resistor is connected in series between the power module and the energy storage capacitor module to limit the charging current.

5. The closed-loop regulated high-voltage power supply according to claim 1, characterized in that, The microcontroller control module uses an STM32F103C8T6 microcontroller, which has PWM output, ADC sampling and serial communication functions, and can adjust the PWM duty cycle in real time according to the capacitor voltage.

6. The closed-loop regulated high-voltage power supply according to claim 1, characterized in that, The electrode spacing of the electromagnetic drive module can be adjusted from 0.1 mm to 5 mm.

7. The closed-loop regulated high-voltage power supply according to claim 1, characterized in that, The electromagnetic drive module generates a magnetic field through an electromagnetic coil and an iron core. When the coil is energized, the movable electrode moves axially; when the coil is de-energized, the movable electrode returns to its initial position under the action of the spring restoring force.

8. The closed-loop regulated high-voltage power supply according to claim 1, characterized in that, It also includes a temperature protection module that automatically adjusts the power input or shuts off the power when the system temperature exceeds a set threshold.

9. A method of using a closed-loop regulated high-voltage power supply as described in any one of claims 1 to 8, characterized in that, Includes the following steps: Step S100: The system is powered on and initialized. The microcontroller control module reads the preset parameters and sets the target voltage and current protection thresholds. Step S200: The power module converts DC power into high-frequency AC power through a full-bridge inverter circuit, and after being stepped up by a step-up transformer, it outputs high-voltage DC power through a voltage doubler rectifier circuit; Step S300: The energy storage capacitor module starts charging. The microcontroller control module samples the capacitor voltage in real time and controls the charging rate by adjusting the PWM duty cycle. Step S400: When the capacitor voltage approaches the target value, the microcontroller control module gradually reduces the PWM duty cycle and enters trickle charging mode to stabilize the capacitor voltage within the set range. Step S500: The electromagnetic drive module adjusts the electrode spacing according to the instruction. By controlling the current intensity of the electromagnetic coil, it pushes the movable electrode to move, thereby achieving precise adjustment of the electrode spacing. Step S600: When the electrode spacing reaches the set value, the system enters the discharge mode, and the energy storage capacitor provides a stable voltage to the electrodes; Step S700: Repeat steps S300 to S600 until a stop command is received.

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