Self-adaptive switching device for supplying power to high-voltage dust removal plate

Abstract

The invention discloses a self-adaptive switching device powered by a high-voltage dust removal plate. The self-adaptive switching device comprises a voltage regulation execution assembly, a dust concentration acquisition assembly, a physical isolation switch assembly and a control module, the voltage regulation execution assembly comprises a first rectifying circuit, an inverter circuit, a high-frequency boosting transformer and a second rectifying circuit which are electrically connected in sequence to form an electric energy conversion link from power frequency alternating current to high-voltage direct current; the physical isolation switch assembly comprises a high-voltage isolation switch and a state indicating lamp. The physical isolation switch assembly and the voltage regulation execution assembly are connected in series in a power supply loop of the high-voltage dust removal plate; a control module with a built-in concentration-voltage mapping algorithm receives a smoke concentration signal of the dust concentration acquisition unit, the control module outputs a corresponding PWM (Pulse Width Modulation) control instruction to an inverter circuit according to the smoke concentration, and the duty ratio is adjusted to change the power supply voltage of the dust removal plate. The self-adaptive switching device powered by the high-voltage dust removal plate has the beneficial effects that the voltage of the dust removal plate is self-adaptive to the working condition and the response speed is high.

Description

Technical Field

[0001] This invention relates to the field of environmental protection equipment technology, specifically to an adaptive switching device for power supply to a high-voltage dust collector plate. Background Technology

[0002] In the field of electrostatic precipitators (ESPs) in power plants, traditional ESPs have long suffered from insufficient voltage regulation capabilities, making them unsuitable for complex and variable operating conditions. On one hand, early power supply devices often employed a fixed voltage output mode, where the plate voltage remained constant after being preset, failing to respond to fluctuations in flue gas dust concentration caused by boiler load variations and changes in coal quality. For example, when the boiler is operating at full load, a sudden increase in dust concentration occurs, and the electric field strength under a fixed voltage is insufficient to fully charge and adsorb a large amount of dust, easily leading to dust escape. Conversely, under low-load, low-dust conditions, a fixed high voltage results in significant energy waste. On the other hand, while some improved devices support voltage regulation, they are mostly manually controlled independently of a single electric field, lacking a coordinated control mechanism. When the dust concentration changes, the voltage setpoint must be manually adjusted, which is not only labor-intensive but also suffers from adjustment lag, often resulting in excessive flue gas turbidity. Summary of the Invention

[0003] To overcome the above-mentioned shortcomings in the prior art, the present invention provides an adaptive switching device for power supply of high-voltage dust collectors that adapts to different operating conditions and has a fast response speed.

[0004] The technical solution of this invention is as follows: An adaptive switching device powered by a high-voltage dust collector includes a voltage regulation actuator, a dust concentration acquisition actuator, a physical isolation switch assembly, and a control module; The voltage regulation execution component includes a first rectifier circuit, an inverter circuit, a high-frequency step-up transformer, and a second rectifier circuit that are connected in sequence to form a power conversion link from power frequency AC to high-voltage DC. The physical disconnect switch assembly includes a high-voltage disconnect switch and a status indicator light, the status indicator light being used to indicate the position of the high-voltage disconnect switch; The physical isolation switch assembly and the voltage regulating actuator assembly are connected in series in the power supply circuit of the high-voltage dust collector plate; The control module has a built-in concentration-voltage mapping algorithm. The control module receives the dust concentration signal from the dust concentration acquisition unit and outputs a corresponding PWM control command to the inverter circuit according to the dust concentration to adjust the duty cycle and change the power supply voltage of the dust collector.

[0005] Preferably, it also includes a current acquisition component, which is used to acquire the current of the power supply circuit of the dust collector and feed it back to the control module. When the current of the power supply circuit exceeds a specified threshold, the control module triggers an alarm.

[0006] In any of the above solutions, it is preferred that the control module acquires the current change rate of the dust collector plate. ; When the load current change rate is positive and exceeds the threshold, the control module reduces the PWM duty cycle output to the inverter circuit and lowers the supply voltage. When the load current change rate is negative and exceeds the threshold, the control module increases the PWM duty cycle output to the inverter circuit and raises the supply voltage.

[0007] In any of the above schemes, it is preferred that the concentration-voltage mapping algorithm presets several dust concentration thresholds, each dust concentration threshold corresponding to a reference power supply voltage, and the control module outputs a PWM control command to make the power supply voltage match the corresponding reference voltage according to the threshold range in which the dust concentration signal is located.

[0008] In any of the above schemes, it is preferred that the inverter circuit is composed of IGBT switching transistors forming a full-bridge inverter topology, and the frequency of the PWM control command output by the control module is 10-20kHz.

[0009] In any of the above schemes, it is preferred that the high voltage DC voltage output by the voltage regulating actuator ranges from 0 to 72 kV.

[0010] In any of the above embodiments, it is preferred that the dust concentration acquisition component includes a laser scattering sensor, and the dust concentration acquisition component is disposed in front of the high-pressure dust collector plate.

[0011] In any of the above embodiments, it is preferred that the physical disconnect switch assembly further includes an arc suppression unit, which is an RC absorption circuit or a zinc oxide surge arrester, used to suppress the high-voltage arc generated during the switching process.

[0012] In any of the above solutions, it is preferred to further include a communication module, wherein the control module is connected to the host computer via the communication module, and the communication module is used to realize data interaction between the control module and the host computer.

[0013] In any of the above solutions, it is preferred that the communication module uses any one of Bluetooth, WIFI, 4G, 5G, ZigBee, LoRa, or NB-IoT as its communication method.

[0014] The adaptive switching device for high-voltage dust collector power supply of the present invention forms a closed-loop control by setting up a dust concentration acquisition component, a current acquisition component, a control module, and a voltage regulation execution component. The dust concentration acquisition component detects the dust concentration in the flue gas in real time and feeds it back to the control module. The control module automatically generates PWM control commands adapted to the current operating conditions based on a preset concentration-voltage mapping logic, driving the voltage regulation execution component to dynamically adjust the output voltage. The dust concentration acquisition component, control module, and voltage regulation execution component can achieve millisecond-level signal reception, transmission, and voltage regulation action execution, thus realizing adaptive voltage operation of the dust collector and providing a fast response speed. Attached Figure Description

[0015] Figure 1 A circuit connection diagram of the adaptive switching device for powering the high-voltage dust collector plate of the present invention.

[0016] Figure 2 A schematic diagram of the first rectifier circuit of the adaptive switching device for powering the high-voltage dust collector plate of the present invention.

[0017] Figure 3 A schematic diagram of the circuit connection of the four-position switch and indicator light of the adaptive switching device for powering the high-pressure dust collector plate of the present invention. Detailed Implementation

[0018] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] In the description of this invention, terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used solely for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, terms such as "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0020] Example 1: In this embodiment, the high-voltage electrostatic precipitator power supply adaptive voltage switch assembly is integrated and installed in the power supply control cabinet of the electrostatic precipitator system, and the control cabinet is fixed to one side of the high-voltage dust removal equipment.

[0021] like Figure 1As shown, the adaptive switching device for powering the high-voltage dust collector plate of the present invention converts 380V AC power into high-voltage DC power via a voltage regulating actuator, and then supplies power to the high-voltage dust collector plate through a physical isolation switch. A dust concentration acquisition component collects the dust concentration at the high-voltage dust collector plate and generates an electrical signal, which is transmitted to the control module. A preset mapping relationship between dust concentration and target voltage is built into the module, which is derived from experiments with the dust collection equipment. When the dust concentration acquisition component transmits the real-time collected dust concentration electrical signal to the control module, the control module first analyzes and processes the signal to determine the specific value of the current dust concentration in the flue gas. Subsequently, based on the built-in mapping relationship, the control module matches the target high-voltage DC voltage value corresponding to the current dust concentration and performs reverse derivation calculations using the turns ratio of the primary and secondary windings of the high-frequency step-up transformer to determine the effective value of the AC output required by the inverter circuit. Finally, the control module generates corresponding PWM control commands. By adjusting the duty cycle of the PWM signal, it drives the IGBT switching transistors of the inverter circuit to switch on and off at a preset frequency, ensuring that the effective value of the AC output from the inverter circuit accurately matches the voltage value at the dust collector plate under the current dust concentration. To ensure both simple algorithm logic and ease of implementation, without requiring complex calculations, the concentration-voltage mapping algorithm presets several dust concentration thresholds, each corresponding to a reference supply voltage.

[0022] To ensure phase-to-phase balance of the 380V AC input, the first rectifier circuit adopts a three-phase full-bridge uncontrolled rectifier topology combined with a three-phase input reactor. The full-bridge topology achieves 120° balanced conduction of the three-phase current through six symmetrically arranged diodes, while the input reactor suppresses current surges and harmonic distortion. Together, they ensure balanced amplitude and phase distribution of the three-phase current, maintaining phase-to-phase balance.

[0023] The inverter circuit consists of a full-bridge inverter topology composed of IGBT switching transistors, and the PWM control command frequency output by the control module is 10-20kHz.

[0024] Considering the characteristics of dust in power plant flue gas—dust concentrations reaching 100-300 g / m³, containing submicron-sized fine particulate matter (PM2.5), and high resistivity components such as SiO2 and Al2O3—the standard distance between the dust collector plate and the corona electrode in power plant electrostatic precipitators is typically 200-350 mm. This also aligns with national environmental standards for pollutant emissions. Furthermore, considering the requirements for adsorbing high dust concentrations and suppressing back corona discharge from high resistivity components, the high-voltage DC output of the voltage regulating actuator ranges from 0-72 kV.

[0025] The 380V power frequency AC is rectified by the first rectifier circuit, inverted by the inverter circuit, and stepped up by the high-frequency step-up transformer, becoming single-phase AC. Therefore, the second rectifier circuit can use a single-phase full-bridge rectifier topology. The core components are high-voltage silicon stack and high-voltage filter capacitor. The AC is converted into pulsating DC through full-wave rectification, and then filtered to output a stable high-voltage DC to meet the power supply requirements of the dust collector.

[0026] A physical disconnect switch assembly is connected in series between the output terminal of the second rectifier circuit and the power supply terminal of the high-voltage dust collector. The physical disconnect switch assembly includes a high-voltage disconnect switch and a status indicator light. The high-voltage disconnect switch has an arc-extinguishing function.

[0027] The status indicator light is dual-color (red and green). One optional linkage between the status indicator light and the high-voltage disconnect switch is achieved through auxiliary contacts. Specifically, the high-voltage disconnect switch has several auxiliary contacts, each mechanically linked to the main circuit of the disconnect switch. The status indicator light is powered by a 220V auxiliary power supply within the control cabinet. The red and green lights are connected in parallel to the 220V auxiliary power supply via their respective built-in auxiliary contacts. When the high-voltage disconnect switch is in the connected position, the green light illuminates; when it is in the electric field position, the red light illuminates; and when the high-voltage disconnect switch is between the connected and electric field positions, neither light illuminates, thus providing direct feedback on the position of the high-voltage disconnect switch.

[0028] like Figure 3 As shown, another optional form for further linking the status indicator and the high-voltage disconnect switch is to add a four-position switch, wherein each position includes a local connection position, a local electric field position, a remote connection position, and a remote electric field position.

[0029] For the local connection voltage boost test, the four-position switch is set to the "local connection position", the high-voltage disconnect switch is set to the connection position, the status indicator light is green, and local operation is achieved through the panel buttons.

[0030] For the local electric field voltage boost test, the four-position switch is set to the "local electric field position", the high-voltage disconnect switch is set to the electric field position, the status indicator light is red, and local operation is achieved through the panel buttons.

[0031] For the remote connection voltage boost test, the four-position switch is set to the "remote connection position", the high-voltage disconnect switch is switched to the connection position, the status indicator light turns green, and the host computer operation is realized.

[0032] For the remote electric field voltage boost test (this is also the normal operating position), switch the four-position switch to the "remote electric field position", switch the high-voltage disconnect switch to the electric field position, and the status indicator light will turn red, enabling the host computer operation.

[0033] By selecting the above four positions, normal operation can be ensured, and the fault can be quickly and accurately determined whether it is in the dust removal electric field or the control cabinet, which is very convenient. In addition, because this invention is equipped with a position switch interlocking circuit and a status indicator circuit, when the high-voltage disconnect switch is between the electric field position and the ground position, the status indicator of the high-voltage disconnect switch will not light up, and the control cabinet will also be unable to start, thereby avoiding damage to the high-voltage disconnect switch by arc discharge.

[0034] Example 2: Based on Example 1, such as Figure 1 As shown, this embodiment adds a current acquisition component. This component uses a Hall effect current sensor and is located in the circuit between the physical isolation switch assembly and the dust collector plate. It is used to acquire the voltage in the dust collector plate circuit. When the power supply circuit current exceeds a specified threshold at a certain concentration, it indicates that the following situations may exist at the dust collector plate: 1. When there is excessive dust accumulation on the dust collector plate, the electric field conductivity between the dust collector plate and the accumulated dust increases, leading to an increase in the power supply circuit current. 2. When an arcing fault occurs in the circuit, the electric field breaks down the air, forming a momentary conductive channel. At this time, the control module triggers an alarm and adjusts the PWM duty cycle to reduce the power supply voltage between the dust collector plates or cuts off the power supply to prevent the fault from escalating.

[0035] Example 3: Based on Example 2, the control module acquires the current change rate of the dust collector plate. The control module adjusts the PWM duty cycle based on the rate of change of current, thereby dynamically regulating the power supply voltage at the dust collector plate and maximizing dust removal efficiency while saving energy.

[0036] Specifically, when the rate of change of current is positive and exceeds the threshold, it indicates increased dust accumulation on the dust collector plate or the occurrence of momentary arcing. Increased dust accumulation can lead to saturation of the dust collector plate, allowing excess dust to easily penetrate the electric field. Arcing generates a localized strong electric field, interfering with the overall adsorption effect and potentially damaging the dust collector plate. In this situation, adjusting the PWM duty cycle to reduce the supply voltage can weaken the excessively strong electric field, restoring its uniformity and ensuring continuous and stable dust removal efficiency.

[0037] When the rate of change of current is negative and exceeds the threshold, it indicates a sudden decrease in the concentration of dust in the flue gas. At this time, the electric field conductivity weakens and the adsorption force is insufficient. The electric field force obtained by the charged dust particles is insufficient to overcome the airflow resistance, making them prone to escape and leading to a decrease in dust removal efficiency. In this case, adjusting the PWM duty cycle to increase the voltage enhances the electric field between the dust removal plates, thus preventing dust escape due to insufficient adsorption force.

[0038] Example 4: Based on any of the embodiments 1-3, in this embodiment, the dust concentration acquisition component includes a laser scattering sensor. The laser scattering sensor has many advantages, such as high detection accuracy, fast response speed, strong anti-interference ability (the laser scattering signal is not affected by flue gas temperature (-20~85℃), humidity and common industrial electromagnetic interference), and wide measurement range (it can cover the concentration range of 0~1000mg / m³).

[0039] The dust concentration acquisition component is positioned in front of the high-voltage dust collector plate. This serves two purposes: firstly, it allows for advance prediction of operating conditions, enabling the control module to acquire data and adjust the power supply voltage accordingly, thus preventing a decrease in dust removal efficiency due to sudden concentration changes; secondly, the circuitry of the dust concentration acquisition component is located away from the dust collector plate to avoid interference from the plate's high electric field.

[0040] Example 5: Based on any of the embodiments 1-4, such as Figure 1 As shown, a communication module is added in this embodiment. The control module is connected to the host computer via the communication module, and the communication module is used to realize data interaction between the control module and the host computer.

[0041] The host computer can acquire data such as dust concentration, power supply voltage, circuit current, and equipment operating status in real time, allowing maintenance personnel to monitor equipment conditions without on-site supervision, thus reducing inspection costs.

[0042] The host computer stores historical operating data such as concentration change curves, voltage adjustment records, and fault logs, which can trace the trend of dust removal efficiency changes and provide data support for equipment maintenance, such as dust removal plate cleaning cycle and sensor calibration. When equipment malfunctions, the host computer can receive alarm signals and push notifications. Maintenance personnel can remotely issue control commands such as shutdown and voltage reduction to quickly respond to faults and reduce downtime.

[0043] The communication module uses any one of Bluetooth, WIFI, 4G, 5G, ZigBee, LoRa, and NB-IoT as its communication method. Chips based on these communication methods have many advantages, such as strong signal transmission reliability, wide adaptability and ability to connect with various control units, high ease of operation, low power consumption, and controllable cost.

[0044] The above-described embodiments are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An adaptive switching device powered by a high-voltage dust collector plate, characterized in that, It includes a voltage regulating actuator, a dust concentration acquisition component, a physical isolation switch component, and a control module; The voltage regulation execution component includes a first rectifier circuit, an inverter circuit, a high-frequency step-up transformer, and a second rectifier circuit that are connected in sequence to form a power conversion link from power frequency AC to high-voltage DC. The physical disconnect switch assembly includes a high-voltage disconnect switch and a status indicator light, the status indicator light being used to indicate the position of the high-voltage disconnect switch; The physical isolation switch assembly and the voltage regulating actuator assembly are connected in series in the power supply circuit of the high-voltage dust collector plate; The control module has a built-in concentration-voltage mapping algorithm. The control module receives the dust concentration signal from the dust concentration acquisition unit and outputs a corresponding PWM control command to the inverter circuit according to the dust concentration to adjust the duty cycle and change the power supply voltage of the dust collector.

2. The adaptive switching device for high-voltage dust collector power supply as described in claim 1, characterized in that, It also includes a current acquisition component, which is used to acquire the current of the power supply circuit of the dust collector and feed it back to the control module. When the current of the power supply circuit exceeds a specified threshold, the control module triggers an alarm.

3. The adaptive switching device for high-voltage dust collector power supply as described in claim 2, characterized in that, The control module acquires the current change rate of the dust collector plate. ; When the load current change rate is positive and exceeds the threshold, the control module reduces the PWM duty cycle output to the inverter circuit and lowers the supply voltage. When the load current change rate is negative and exceeds the threshold, the control module increases the PWM duty cycle output to the inverter circuit and raises the supply voltage.

4. The adaptive switching device for high-voltage dust collector plate power supply as described in any one of claims 1-3, characterized in that, The concentration-voltage mapping algorithm presets several dust concentration thresholds, each of which corresponds to a reference power supply voltage. The control module outputs PWM control commands based on the threshold range in which the dust concentration signal is located, so that the power supply voltage matches the corresponding reference voltage.

5. The adaptive switching device for high-voltage dust collector power supply as described in claim 4, characterized in that, The inverter circuit consists of a full-bridge inverter topology composed of IGBT switching transistors, and the PWM control command frequency output by the control module is 10-20kHz.

6. The adaptive switching device for high-voltage dust collector plate power supply as described in any one of claims 1-3 and 5, characterized in that, The high voltage output of the voltage regulating actuator ranges from 0 to 72 kV.

7. The adaptive switching device for high-voltage dust collector power supply as described in claim 6, characterized in that, The dust concentration acquisition component includes a laser scattering sensor, and the dust concentration acquisition component is positioned in front of the high-pressure dust collector plate.

8. The adaptive switching device for high-voltage dust collector power supply as described in claim 7, characterized in that, The physical disconnect switch assembly also includes an arc suppression unit, which is an RC absorption circuit or a zinc oxide surge arrester, used to suppress the high-voltage arc generated during the switching process.

9. The adaptive switching device for high-voltage dust collector power supply as described in claim 8, characterized in that, It also includes a communication module, through which the control module is connected to the host computer, and the communication module is used to realize data interaction between the control module and the host computer.

10. The adaptive switching device for high-voltage dust collector plate power supply as described in claim 9, characterized in that, The communication module can communicate using any one of the following methods: Bluetooth, WIFI, 4G, 5G, ZigBee, LoRa, or NB-IoT.

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