Intelligent control system of self-coupling compensation type alternating current barostat

Abstract

The invention relates to the technical field of intelligent control of a barostat, in particular to an intelligent control system of a self-coupling compensation type alternating current barostat, which comprises a voltage signal preprocessing module, a voltage signal processing module, a voltage signal processing module and a voltage signal processing module, a voltage transformer is adopted to reduce the high-voltage AC signal from high voltage to low-voltage AC signal; setting a voltage threshold value, adjusting a converted voltage value, and recording an adjustment multiple; the low-voltage alternating-current signal direct-current conversion module receives a voltage alternating-current signal and converts the low-voltage alternating-current signal into a smooth direct-current voltage; the voltage comparison and instruction output module receives the direct-current voltage output by the low-voltage alternating-current signal direct-current conversion module, the direct-current voltage comprises the grid-side direct-current voltage and the load-side direct-current voltage, the grid-side direct-current voltage and the load-side direct-current voltage are reduced by adjusting the multiple, and the reduced grid-side direct-current voltage and the reduced load-side direct-current voltage are compared; and outputting a voltage instruction according to the comparison result.

Description

Technical Field

[0001] This invention relates to the field of intelligent control technology for constant voltage regulators, and more specifically, to an intelligent control system for an autotransformer-compensated AC constant voltage regulator. Background Technology

[0002] During the operation of the power system, the grid voltage is affected by factors such as transmission distance, load fluctuation, and the switching between peak and off-peak electricity consumption periods, often resulting in voltage that is too high, too low, or momentary fluctuations. Precision machine tools in industrial production, CT and MRI equipment in the medical field, data center servers, and precision instruments in laboratories have extremely high requirements for the stability of the power supply voltage. Voltage instability can easily lead to a decrease in the operating accuracy of equipment, frequent failures, or even damage. Therefore, it is necessary to rely on AC constant voltage transformers to ensure the quality of power supply.

[0003] Traditional autotransformer-compensated AC constant voltage transformers can regulate the output voltage through the compensation winding of the autotransformer, but their control methods are mostly manual adjustment or semi-automatic control based on simple relays, which have obvious drawbacks: On the one hand, manual adjustment relies on manual monitoring of voltage and operation of the voltage adjustment knob, resulting in a slow response speed (usually several seconds to tens of seconds), making it unable to respond to rapid fluctuations in grid voltage in a timely manner, and the adjustment accuracy is affected by the operator's experience, making it difficult to meet the power supply requirements of high-precision equipment; on the other hand, constant voltage transformers controlled by simple relays often use ordinary voltage transformers in their sampling stage, without optimizing the transformation ratio adjustment for the voltage difference between the grid side and the load side. When the voltage value after the grid side or load side conversion is too small, it is easily affected by interference signals such as electromagnetic radiation from surrounding equipment, resulting in an extremely low signal-to-noise ratio of the sampling signal, which in turn leads to misjudgment of voltage adjustment commands, resulting in problems such as false triggering of overvoltage or undervoltage protection or untimely voltage adjustment.

[0004] Meanwhile, traditional constant voltage regulators lack a complete rectification, filtering, and voltage regulation process in their signal processing stage: rectification often uses half-wave rectifier circuits, resulting in a large ripple coefficient for the output unidirectional pulsating DC signal; the filtering stage uses only small-capacity capacitors, which cannot effectively filter out pulsating components; the voltage regulation stage does not combine the synergistic design of current-limiting resistors and Zener diodes, making it difficult to maintain stable output voltage when the input voltage fluctuates or the load changes, leading to insufficient accuracy of the voltage signal obtained by the subsequent control circuit, further affecting the voltage regulation accuracy. In addition, traditional constant voltage regulators lack voltage restoration and intelligent command decision-making mechanisms, and cannot dynamically adjust the voltage regulation strategy according to the actual voltage conditions on the grid side and the load side. They can only regulate voltage according to a fixed mode, resulting in poor adaptability and difficulty in meeting the diverse voltage stability requirements in different scenarios. In view of this, we propose an intelligent control system for an autotransformer-compensated AC constant voltage regulator. Summary of the Invention

[0005] The purpose of this invention is to solve the problem that traditional autotransformer-compensated AC constant voltage transformers are unable to provide stable and accurate voltage to electrical equipment when the grid voltage fluctuates and the load changes due to insufficient voltage sampling accuracy, inaccurate signal processing, and lack of intelligent and automated voltage regulation control.

[0006] To achieve the above objectives, this invention provides an intelligent control system for an autotransformer-compensated AC constant voltage transformer, comprising a voltage signal preprocessing module, a low-voltage AC signal DC-DC conversion module, and a voltage comparison and command output module, wherein: The voltage signal preprocessing module includes a high-voltage AC signal acquisition and step-down unit and a voltage threshold adjustment and multiplier recording unit; the high-voltage AC signal acquisition and step-down unit is used to acquire high-voltage AC signals, including grid-side voltage. The voltage is then measured on the load side, and a low-voltage AC signal is set. A voltage transformer is used to step down the high-voltage AC signal from high voltage to low voltage. The voltage threshold adjustment and multiplier recording unit sets the voltage threshold. Adjust the converted voltage value and record the adjustment factor; The low-voltage AC signal DC-DC conversion module receives the low-voltage AC signal after adjusting the grid-side voltage and load-side voltage, and converts the low-voltage AC signal into a smooth DC voltage. The voltage comparison and command output module receives the DC voltage output by the low-voltage AC signal DC-DC conversion module, which includes the grid-side DC voltage and the load-side DC voltage. The grid-side DC voltage and the load-side DC voltage are restored by the corresponding adjustment multiple in the voltage threshold adjustment and multiplier recording unit. The restored grid-side DC voltage and the restored load-side DC voltage are compared, and a voltage command is output according to the comparison result.

[0007] Preferably, the voltage transformer in the high-voltage AC signal acquisition and step-down unit includes a primary winding, a secondary winding, and a closed iron core. The primary winding is connected to the high-voltage side, specifically the grid input voltage and the load output voltage. The secondary winding is connected to a high-impedance detection circuit. After the primary winding is energized, it generates an alternating excitation current, which excites a periodically changing main magnetic flux in the closed iron core. When the main magnetic flux passes through the secondary winding, according to the principle of electromagnetic induction, an alternating induced electromotive force is induced in the secondary winding. Since the secondary winding is connected to a high-impedance detection circuit, the low-voltage AC signal at the secondary end is approximately equal to its induced electromotive force. According to the transformer turns ratio, the ratio of the primary voltage of the primary winding to the secondary voltage of the secondary winding is equal to the ratio of the number of turns of the primary winding to the number of turns of the secondary winding. Then based on the ratio After analyzing the number of turns in the primary winding and the number of turns in the secondary winding, an alert signal is output to adjust the corresponding number of turns, thereby reducing the voltage on both the grid side and the load side to a low-voltage AC signal.

[0008] Preferably, when the high-voltage AC signal acquisition and step-down unit calculates the ratio of the primary voltage of the primary winding to the secondary voltage of the secondary winding, it first compares the grid voltage and the load voltage to retrieve the maximum AC signal. That is, if the grid voltage is less than the load voltage, the load voltage is the maximum AC signal. Then, the maximum AC signal is set as the primary voltage of the primary winding, and the number of turns of the primary winding and the number of turns of the secondary winding are adjusted using the maximum AC signal so that when the maximum AC signal is reduced to the low-voltage AC signal, the voltage value of the maximum AC signal is less than or equal to the voltage value of the low-voltage AC signal.

[0009] Preferably, the voltage threshold adjustment and multiplier recording unit is used to set the voltage threshold and receive the voltage value after conversion between the grid-side voltage and the load-side voltage. If the voltage value after grid-side voltage conversion is less than the voltage threshold, the converted voltage value is adjusted by multiplying itself by an adjustment factor to make the adjusted voltage value equal to the voltage threshold, and the adjustment factor is recorded; if the voltage value after load-side voltage conversion is also less than the voltage threshold, it is adjusted synchronously.

[0010] Preferably, the low-voltage AC signal DC-DC conversion module includes a bridge rectifier circuit unit, a capacitor filter circuit unit, and a three-terminal constant voltage regulator unit; the bridge rectifier circuit unit is used to rectify the low-voltage AC signal, the capacitor filter circuit unit is used to filter the rectified low-voltage AC signal, and the three-terminal constant voltage regulator unit is used to regulate and filter the low-voltage AC signal.

[0011] The bridge rectifier circuit unit uses a bridge rectifier circuit composed of four diodes to rectify low-voltage AC signals. Rectification is performed using the unidirectional conductivity of diodes to rectify low-voltage AC signals. Rectification is performed to obtain a unidirectional pulsating DC voltage. This allows the low-voltage AC signal, whose direction changes continuously over time, to be... Converted into a unidirectional pulsating DC signal with a fixed direction. ; When the AC signal is in the positive half-cycle, the two diagonally opposite diodes are forward-biased, and the current flows through the conducting diode, the load, and the other conducting diode to form a loop. At this time, the voltage across the load is a positive pulsating voltage. When the AC signal is in the negative half-cycle, the other two diagonally opposite diodes are forward-biased, and the current flows through the load in the same direction as in the positive half-cycle, so the load terminals can still receive a positive pulsating voltage.

[0012] Preferably, the capacitor filter circuit unit uses a capacitor filter circuit to filter unidirectional pulsating DC signals. The capacitor filter circuit includes electrolytic capacitors. Load resistance The rectifier circuit output terminal works as follows: the capacitor filter circuit connects the rectifier circuit output terminal with the load resistor. Large-capacity electrolytic capacitors connected in parallel The charging and discharging characteristics of a capacitor, which prevents voltage abrupt changes, are used to smooth unidirectional pulsating DC signals. ; If unidirectional pulsating DC voltage higher than the voltage across the capacitor At that time, the output control signal drives the electrolytic capacitor. When charging, the rectifier diode is forward-biased, and current flows through the rectifier diode to the electrolytic capacitor. Voltage across the capacitor Rapidly rises to the peak value of the rectified output voltage Its time-varying behavior follows the zero-state response of a first-order circuit: ,in This refers to charging time; If unidirectional pulsating DC voltage lower than the voltage across the capacitor At that time, the output control signal drives the electrolytic capacitor. When in the discharge state, the rectifier diode is reverse-biased and cut off, flowing through the load resistor. The stored electrical energy is released to maintain a stable voltage across the load, and the discharge process follows a zero-input response: and load resistance The discharge rate that releases stored electrical energy is determined by the RC time constant. Decision, if time constant The larger the value, the slower the discharge speed, the smaller the voltage fluctuation, and the better the filtering effect, resulting in a smoother output voltage. This provides a high-quality DC signal for subsequent voltage regulation, ensuring that the electrical equipment receives a stable and low-fluctuation power supply, and improving the stability and reliability of equipment operation.

[0013] Preferably, the three-terminal constant voltage regulator unit uses a unidirectional pulsating DC voltage after being regulated and filtered by a three-terminal constant voltage regulator. Receives unstable DC voltage after rectification and filtering. Unstable DC voltage > Output fixed DC voltage ; Set the actual current limiting resistor and the actual current limiting resistor When the three-terminal constant voltage regulator is connected in series with a Zener diode, if the DC voltage is unstable... Increase, load current Reduce (load resistance) When the voltage increases, the output voltage When there is an upward trend, the sampling circuit inside the three-terminal constant voltage transformer (consisting of the upper voltage divider resistor) Lower voltage divider resistor (Composition) on output voltage Voltage division yields the sampled voltage: ; Then, an error amplifier circuit is used to sample the voltage. With reference voltage Compare with reference voltage Comparison generates an error signal. Control the pressure drop of the regulating pipe Increase error signal This cancels out the output voltage. The increase; When the DC voltage is unstable Reduce, or load current When increased, the output voltage There is a decreasing trend, compared with the sampling voltage. With reference voltage The pressure drop of the adjusting pipe is controlled based on the comparison results. Reduce, thereby reducing the output voltage Increase, offset the output voltage A downward trend.

[0014] Preferably, the working principle of the three-terminal constant voltage regulator unit is to set the minimum reverse breakdown current as follows: The maximum reverse breakdown current is The minimum input voltage is The maximum value is The minimum load current is The maximum value is : When the input voltage is at its maximum and the load current is at its minimum, the current flowing through the Zener diode is at its maximum and must not exceed the maximum reverse breakdown current. At this point, the minimum value of the current-limiting resistor is: ; When the input voltage is at its minimum and the load current is at its maximum, the current flowing through the Zener diode is at its minimum, but it cannot be less than the minimum reverse breakdown current. At this time, the maximum value of the current-limiting resistor is: ; Then at the maximum value of the current-limiting resistor To the minimum value of the current limiting resistor Internally set actual current limiting resistor This ensures that the Zener diode operates within a safe current range.

[0015] Preferably, the voltage comparison and command output module receives the DC voltage output by the low-voltage AC signal DC conversion module, which includes the DC voltage on the grid side and the DC voltage on the load side, and restores the DC voltage on the grid side and the DC voltage on the load side by using the corresponding adjustment multiple in the voltage threshold adjustment and multiplier recording unit. Compare and restore the DC voltage on the grid side and the DC voltage on the load side: If the restored DC voltage on the grid side is less than the restored DC voltage on the load side, it is determined that the load side voltage is too high, and a voltage reduction command is output to reduce the restored DC voltage on the load side to the restored DC voltage on the grid side. If the restored grid-side DC voltage is greater than the restored load-side DC voltage, then the load-side voltage is determined to be too low, and a voltage increase command is output to reduce the restored grid-side DC voltage to the restored load-side DC voltage.

[0016] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall module of the present invention; Figure 2 This is a flowchart illustrating the working principle of the high-voltage AC signal acquisition and step-down unit of the present invention; Figure 3 This is a flowchart illustrating the working principle of the voltage threshold adjustment and multiplier recording unit of the present invention. Figure 4 This is a flowchart illustrating the collaborative working principle of the various modules in this invention.

[0018] The meanings of the labels in the diagram are as follows: 100. Voltage signal preprocessing module; 110. High-voltage AC signal acquisition and step-down unit; 120. Voltage threshold adjustment and multiplier recording unit; 200. Low-voltage AC signal DC-DC conversion module; 210. Bridge rectifier circuit unit; 220. Capacitor filter circuit unit; 230. Three-terminal constant voltage regulator unit; 300. Voltage comparison and command output module. Detailed Implementation

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. 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.

[0020] refer to Figures 1-4 An intelligent control system for an autotransformer-compensated AC constant voltage transformer includes a voltage signal preprocessing module 100, a low-voltage AC signal DC-DC conversion module 200, and a voltage comparison and command output module 300, wherein: The voltage signal preprocessing module 100 includes a high-voltage AC signal acquisition and step-down unit 110 and a voltage threshold adjustment and multiplier recording unit 120; the high-voltage AC signal acquisition and step-down unit 110 is used to acquire high-voltage AC signals, including grid-side voltage. and load-side voltage (Grid-side voltage) and load-side voltage Typically a high voltage value of 220V), then a low voltage AC signal is set. A voltage transformer is used to step down the high-voltage AC signal from high voltage to low-voltage AC signal. Specifically: A voltage transformer consists of a primary winding, a secondary winding, and a closed iron core, wherein the primary winding is connected to the high-voltage side (i.e., the grid input voltage). Load-side output voltage The secondary winding is connected to a high-impedance detection circuit (approximately no-load operation); after the primary winding is energized, an alternating excitation current is generated, which in turn excites a periodically changing main magnetic flux in the closed iron core. When the main magnetic flux passes through the secondary winding, according to the principle of electromagnetic induction, an alternating induced electromotive force is induced in the secondary winding. Since the secondary winding is connected to a high-impedance detection circuit (approximately operating under no-load conditions), the low-voltage AC signal at the secondary end is approximately equal to its induced electromotive force. According to the transformer turns ratio, the primary voltage of the primary winding... (i.e., grid input voltage) Load-side output voltage ) and the secondary voltage of the secondary winding (where the secondary voltage) This is a low-voltage AC signal. )ratio ,in This refers to the number of turns in the primary winding. This refers to the number of turns in the secondary winding. Then based on the ratio Analysis of the number of turns in the primary winding Number of turns in the secondary winding Then, an alert signal is output, and the corresponding number of turns is adjusted to adjust the grid-side voltage. and load-side voltage The voltage of all signals is reduced to low-voltage AC signals. ; Calculate the primary voltage of the primary winding. Secondary voltage of the secondary winding ratio At that time, the high-voltage AC signal acquisition and step-down unit 110 first compares the voltage on the grid side. and load-side voltage Adjust to the maximum AC signal That is: if the grid-side voltage <Load side voltage Then determine the load-side voltage. Maximum AC signal ; Then set the maximum AC signal. The primary voltage of the primary winding Using the maximum AC signal Adjust the number of turns of the primary winding Number of turns in the secondary winding This makes the maximum AC signal Reduced to low voltage AC signal At that time, the maximum AC signal Voltage value ≤ low voltage AC signal The voltage value (ensuring maximum AC signal under the premise of adjustable turns) The voltage value is closest to the AC signal. (voltage value), thus making both grid-side voltage Larger, or the load-side voltage Even at higher voltages, it can ensure that the corresponding voltage value is less than the AC signal. The voltage value.

[0021] Furthermore, it was taken into consideration that if the grid-side voltage... Or load-side voltage In this process, if a certain voltage value becomes very small after conversion, the proportion of interference signals (such as electromagnetic radiation from surrounding equipment) will increase significantly, resulting in an extremely low signal-to-noise ratio. This will adversely affect subsequent data acquisition, analysis, and control based on these voltage signals. For example, it may cause large errors in voltage monitoring or inaccurate judgment of the constant voltage regulator's adjustment commands, ultimately affecting the constant voltage regulator's stable control of the output voltage. Therefore, the voltage threshold adjustment and multiplier recording unit 120 is used to set the voltage threshold. Receive grid-side voltage Load side voltage Converted voltage value Voltage value ; If voltage value <Voltage threshold When that happens, adjust the voltage value. for The adjusted voltage value =Voltage threshold And record the adjustment factor. ; If voltage value <Voltage threshold If so, adjust it in the same way as described above; This enables the subsequent low-voltage AC signal DC-DC conversion module 200 to convert the low-voltage AC signal. For smooth DC voltage At that time, by changing the grid-side voltage Load side voltage Adjust to voltage threshold This effectively avoids the problems of high interference signal ratio and low signal-to-noise ratio caused by excessively low voltage values, ensuring voltage signal quality and providing a reliable signal foundation for subsequent accurate voltage acquisition, analysis, and intelligent control of the constant voltage device.

[0022] Furthermore, considering that low-voltage AC signals themselves have problems such as periodic changes in voltage direction and magnitude, and contain harmonics and interference, if used directly, they cannot provide stable and high-quality power support for subsequent circuits, which will adversely affect voltage monitoring and regulation based on the signal, and may even cause equipment to malfunction or malfunction due to voltage instability and noise. To avoid these situations, the low-voltage AC signal DC-DC conversion module 200 in this invention receives the grid-side voltage. and load-side voltage Adjusted low-voltage AC signal Convert low-voltage AC signals For smooth DC voltage Specifically, the low-voltage AC signal is regulated by a bridge rectifier circuit unit 210, a capacitor filter circuit unit 220, and a three-terminal constant voltage regulator unit 230, respectively. It performs rectification, filtering, and voltage regulation; Bridge rectifier circuit unit 210 uses a bridge rectifier circuit composed of four diodes to rectify low-voltage AC signals. Rectification is performed to ensure that regardless of whether the low-voltage AC signal is in the positive or negative half-cycle, the unidirectional conductivity of the diode allows current to flow through the load in a fixed direction. This solves the problem that AC signals with periodic changes in direction cannot directly power DC equipment or subsequent DC processing circuits. The specific working principle is as follows: The bridge rectifier circuit unit 210 utilizes the unidirectional conductivity of the diode to rectify the low-voltage AC signal... Rectification is performed to obtain a unidirectional pulsating DC voltage. This allows the low-voltage AC signal, whose direction changes continuously over time, to be... Converted into a unidirectional pulsating DC signal with a fixed direction. ; When the AC signal is in the positive half-cycle ( When the two diagonally opposite diodes are forward-biased, the current flows through the conducting diode, the load, and the other conducting diode to form a loop. At this time, the voltage across the load is a positive-direction pulsating voltage. When the AC signal is in the negative half-cycle ( The other two diagonally opposite diodes are forward-biased, and the current flows through the load in the same direction as during the positive half-cycle, so a positive pulsating voltage can still be obtained across the load. By utilizing the unidirectional conductivity of diodes, the low-voltage AC signal whose direction changes continuously over time can ultimately be converted. Converted into a unidirectional pulsating DC signal with a fixed direction. .

[0023] The capacitor filter circuit unit 220 uses a capacitor filter circuit to filter unidirectional pulsating DC signals. The capacitor filter circuit includes electrolytic capacitors. Load resistance The rectifier circuit output terminal works as follows: the capacitor filter circuit connects the rectifier circuit output terminal with the load resistor. Large-capacity electrolytic capacitors connected in parallel The charging and discharging characteristics of a capacitor, which prevents voltage abrupt changes, are used to smooth unidirectional pulsating DC signals. ; If unidirectional pulsating DC voltage higher than the voltage across the capacitor At that time, the output control signal drives the electrolytic capacitor. When charging, the rectifier diode is forward-biased, and current flows through the rectifier diode to the electrolytic capacitor. Voltage across the capacitor Rapidly rises to the peak value of the rectified output voltage Its time-varying behavior follows the zero-state response of a first-order circuit: ,in This refers to charging time; If unidirectional pulsating DC voltage lower than the voltage across the capacitor At that time, the output control signal drives the electrolytic capacitor. When in the discharge state, the rectifier diode is reverse-biased and cut off, flowing through the load resistor. The stored electrical energy is released to maintain a stable voltage across the load, and the discharge process follows a zero-input response: and load resistance The discharge rate that releases stored electrical energy is determined by the RC time constant. Decision, if time constant The larger the value, the slower the discharge speed, the smaller the voltage fluctuation, and the better the filtering effect, resulting in a smoother output voltage. This provides a high-quality DC signal for subsequent voltage regulation, ensuring that the electrical equipment receives a stable and low-fluctuation power supply, and improving the stability and reliability of equipment operation.

[0024] The three-terminal constant voltage regulator unit 230 uses the unidirectional pulsating DC voltage after voltage regulation and filtering by a three-terminal constant voltage regulator. Receives unstable DC voltage after rectification and filtering. Unstable DC voltage > (That is, the input-output pressure difference is at least) ); Output fixed DC voltage ; Specifically, by setting the actual current-limiting resistor and the actual current limiting resistor It is connected in series with a Zener diode to ensure that the Zener diode operates within a safe current range. The operating principle is based on setting a minimum reverse breakdown current of... The maximum reverse breakdown current is The minimum input voltage is The maximum value is The minimum load current is The maximum value is : When the input voltage is at its maximum and the load current is at its minimum, the current flowing through the Zener diode is at its maximum and must not exceed the maximum reverse breakdown current. At this point, the minimum value of the current-limiting resistor is: ; When the input voltage is at its minimum and the load current is at its maximum, the current flowing through the Zener diode is at its minimum, but it cannot be less than the minimum reverse breakdown current. At this time, the maximum value of the current-limiting resistor is: ; Then at the maximum value of the current-limiting resistor To the minimum value of the current limiting resistor Internally set actual current limiting resistor This ensures that the Zener diode operates within a safe current range.

[0025] When the three-terminal constant voltage regulator unit 230 is used for voltage regulation, if the DC voltage is unstable: Increase, load current Reduce (load resistance) When the voltage increases, the output voltage When there is an upward trend, the sampling circuit inside the three-terminal constant voltage transformer (consisting of the upper voltage divider resistor) Lower voltage divider resistor (Composition) on output voltage Voltage division yields the sampled voltage: ; Then, an error amplifier circuit is used to sample the voltage. With reference voltage Compare with reference voltage Comparison generates an error signal. ( (For error amplifier gain), control the voltage drop of the regulating transistor. Increase error signal This cancels out the output voltage. The increase, specifically ; When the DC voltage is unstable Reduce, or load current Increase (load resistance) When the output voltage decreases, There is a decreasing trend, compared with the sampling voltage. With reference voltage The pressure drop of the adjusting pipe is controlled based on the comparison results. Reduce, thereby reducing the output voltage Increase, offset the output voltage The downward trend: specific This enables precise voltage regulation and control of the output voltage. The beneficial effect is that it can maintain a stable output voltage under conditions such as input voltage fluctuations and load changes, providing a reliable DC power supply for subsequent circuits or electrical equipment, ensuring the normal operation of the equipment, and improving the stability and reliability of the power supply.

[0026] The voltage comparison and command output module 300 receives the DC voltage output from the low-voltage AC signal DC-DC conversion module 200, including the DC voltage from the grid side. DC voltage on the load side The voltage threshold adjustment and the corresponding adjustment multiple in the multiplier recording unit 120 are used. Adjust the multiplier Restore DC voltage on the grid side for DC voltage on the load side for ; Comparison and restoration of DC voltage on the grid side , restore the DC voltage on the load side : If the DC voltage on the grid side is restored <Restore load-side DC voltage If the load-side voltage is determined to be too high, a voltage reduction command is output to restore the DC voltage on the load side. Reduce to restore DC voltage on the grid side ; If the DC voltage on the grid side is restored >Restore the DC voltage on the load side If the load-side voltage is determined to be too low, a voltage increase command is output to restore the DC voltage on the grid side. Reduce to the DC voltage on the load side. ; Thus, the voltage comparison and command output module 300 can accurately monitor and intelligently regulate the voltage, ensuring the stability of the load-side voltage, guaranteeing the operation of electrical equipment under stable voltage, improving power reliability and equipment lifespan, and realizing automated and refined voltage management, reducing manual intervention, and improving the intelligence level and working efficiency of the constant voltage device.

[0027] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. An intelligent control system for an autotransformer-compensated AC constant voltage transformer, characterized in that, It includes a voltage signal preprocessing module (100), a low-voltage AC signal DC-DC conversion module (200), and a voltage comparison and command output module (300), wherein: The voltage signal preprocessing module (100) includes a high-voltage AC signal acquisition and step-down unit (110) and a voltage threshold adjustment and multiplier recording unit (120). The high-voltage AC signal acquisition and step-down unit (110) is used to acquire high-voltage AC signals, which include grid-side voltage and load-side voltage. Then, a low-voltage AC signal is set, and a voltage transformer is used to step down the high-voltage AC signal from high voltage to low voltage. The voltage threshold adjustment and multiplier recording unit (120) sets the voltage threshold, adjusts the converted voltage value, and records the adjustment multiplier. The low-voltage AC signal DC-DC conversion module (200) receives the low-voltage AC signal after the grid-side voltage and load-side voltage are adjusted, and converts the low-voltage AC signal into a smooth DC voltage; the voltage comparison and command output module (300) receives the DC voltage output by the low-voltage AC signal DC-DC conversion module (200), which includes the grid-side DC voltage and the load-side DC voltage restored by the corresponding adjustment multiple in the voltage threshold adjustment and multiplier recording unit (120), compares the restored grid-side DC voltage and the restored load-side DC voltage, and outputs a voltage command according to the comparison result.

2. The intelligent control system for an autotransformer-compensated AC constant voltage transformer according to claim 1, characterized in that: The voltage transformer in the high-voltage AC signal acquisition and step-down unit (110) includes a primary winding, a secondary winding, and a closed iron core. The primary winding is connected to the high-voltage side, which is specifically the grid input voltage and the load output voltage. The secondary winding is connected to a high-impedance detection circuit. After the primary winding is energized, it generates an alternating excitation current, which excites a periodically changing main magnetic flux in the closed iron core. When the main magnetic flux passes through the secondary winding, according to the principle of electromagnetic induction, an alternating induced electromotive force is induced in the secondary winding. According to the transformer turns ratio, the ratio of the primary voltage of the primary winding to the secondary voltage of the secondary winding is equal to the ratio of the number of turns of the primary winding to the number of turns of the secondary winding. Then, based on the ratio analysis, the number of turns in the primary winding and the number of turns in the secondary winding are determined, and a reminder signal is output to adjust the corresponding number of turns.

3. The intelligent control system for an autotransformer-compensated AC constant voltage transformer according to claim 2, characterized in that: When the high-voltage AC signal acquisition and step-down unit (110) calculates the ratio of the primary voltage of the primary winding to the secondary voltage of the secondary winding, it first compares the grid voltage and the load voltage to retrieve the maximum AC signal. That is, if the grid voltage is less than the load voltage, the load voltage is the maximum AC signal. Then, the maximum AC signal is set as the primary voltage of the primary winding. The number of turns of the primary winding and the number of turns of the secondary winding are adjusted using the maximum AC signal so that when the maximum AC signal is reduced to the low-voltage AC signal, the voltage value of the maximum AC signal is less than or equal to the voltage value of the low-voltage AC signal.

4. The intelligent control system for an autotransformer-compensated AC constant voltage transformer according to claim 3, characterized in that: The voltage threshold adjustment and multiplier recording unit (120) is used to set the voltage threshold and receive the voltage value after the grid side voltage and load side voltage are converted. If the voltage value after grid-side voltage conversion is less than the voltage threshold, the converted voltage value is adjusted by multiplying itself by an adjustment factor to make the adjusted voltage value equal to the voltage threshold, and the adjustment factor is recorded; if the voltage value after load-side voltage conversion is also less than the voltage threshold, it is adjusted synchronously.

5. The intelligent control system for an autotransformer-compensated AC constant voltage transformer according to claim 4, characterized in that: The low-voltage AC signal DC-DC conversion module (200) includes a bridge rectifier circuit unit (210), a capacitor filter circuit unit (220), and a three-terminal constant voltage regulator unit (230); the bridge rectifier circuit unit (210) is used to rectify the low-voltage AC signal, the capacitor filter circuit unit (220) is used to filter the rectified low-voltage AC signal, and the three-terminal constant voltage regulator unit (230) is used to regulate and filter the low-voltage AC signal. The bridge rectifier circuit unit (210) uses a bridge rectifier circuit composed of four diodes to rectify low-voltage AC signals. Rectification is performed using the unidirectional conductivity of diodes to rectify low-voltage AC signals. Rectification is performed to obtain a unidirectional pulsating DC voltage. This allows the low-voltage AC signal, whose direction changes continuously over time, to be... Converted into a unidirectional pulsating DC signal with a fixed direction. ; When the AC signal is in the positive half-cycle, the two diagonally opposite diodes are forward-biased, and the current flows through the conducting diode, the load, and the other conducting diode to form a loop. At this time, the voltage across the load is a positive pulsating voltage. When the AC signal is in the negative half-cycle, the other two diagonally opposite diodes are forward-biased, and the current flows through the load in the same direction as in the positive half-cycle, so the load terminals can still receive a positive pulsating voltage.

6. The intelligent control system for an autotransformer-compensated AC constant voltage transformer according to claim 5, characterized in that: The capacitor filter circuit unit (220) uses a capacitor filter circuit to filter unidirectional pulsating DC signals. The capacitor filter circuit includes electrolytic capacitors. Load resistance The rectifier circuit output terminal works as follows: the capacitor filter circuit connects the rectifier circuit output terminal with the load resistor. Large-capacity electrolytic capacitors connected in parallel The charging and discharging characteristics of a capacitor, which prevents voltage abrupt changes, are used to smooth unidirectional pulsating DC signals. ; If unidirectional pulsating DC voltage higher than the voltage across the capacitor At that time, the output control signal drives the electrolytic capacitor. When charging, the rectifier diode is forward-biased, and current flows through the rectifier diode to the electrolytic capacitor. Voltage across the capacitor Rapidly rises to the peak value of the rectified output voltage Its time-varying behavior follows the zero-state response of a first-order circuit: ,in This refers to charging time; If unidirectional pulsating DC voltage lower than the voltage across the capacitor At that time, the output control signal drives the electrolytic capacitor. When in the discharge state, the rectifier diode is reverse-biased and cut off, flowing through the load resistor. The stored electrical energy is released to maintain a stable voltage across the load, and the discharge process follows a zero-input response: and load resistance The discharge rate that releases stored electrical energy is determined by the RC time constant. Decision, if time constant The larger the value, the slower the discharge speed, the smaller the voltage fluctuation, and the better the filtering effect, resulting in a smoother output voltage. This provides a high-quality DC signal for subsequent voltage regulation, ensuring that the electrical equipment receives a stable and low-fluctuation power supply, and improving the stability and reliability of equipment operation.

7. The intelligent control system for an autotransformer-compensated AC constant voltage transformer according to claim 6, characterized in that: The three-terminal constant voltage regulator unit (230) uses the unidirectional pulsating DC voltage after three-terminal constant voltage regulator stabilization and filtering. Receives unstable DC voltage after rectification and filtering. Unstable DC voltage > Output fixed DC voltage ; Set the actual current limiting resistor and the actual current limiting resistor When the three-terminal constant voltage regulator is connected in series with a Zener diode, if the DC voltage is unstable... Increase, load current Reduce (load resistance) When the voltage increases, the output voltage When there is an upward trend, the sampling circuit inside the three-terminal constant voltage transformer (consisting of the upper voltage divider resistor) Lower voltage divider resistor (Composition) on output voltage Voltage division yields the sampled voltage: ； Then, an error amplifier circuit is used to sample the voltage. With reference voltage Compare with reference voltage Comparison generates error signals Control the pressure drop of the regulating pipe Increase error signal This cancels out the output voltage. The increase; When unstable DC voltage Reduce, or load current When increased, the output voltage There is a decreasing trend, compared with the sampling voltage. With reference voltage The pressure drop of the adjusting pipe is controlled based on the comparison results. Reduce, thereby reducing the output voltage Increase, offset the output voltage A downward trend.

8. The intelligent control system for an autotransformer-compensated AC constant voltage transformer according to claim 7, characterized in that: The working principle of the three-terminal constant voltage regulator unit (230) is set to a minimum reverse breakdown current of... The maximum reverse breakdown current is The minimum input voltage is The maximum value is The minimum load current is The maximum value is : When the input voltage is at its maximum and the load current is at its minimum, the current flowing through the Zener diode is at its maximum and must not exceed the maximum reverse breakdown current. At this point, the minimum value of the current-limiting resistor is: ; When the input voltage is at its minimum and the load current is at its maximum, the current flowing through the Zener diode is at its minimum, but it cannot be less than the minimum reverse breakdown current. At this time, the maximum value of the current-limiting resistor is: ; Then at the maximum value of the current-limiting resistor To the minimum value of the current limiting resistor Internally set actual current limiting resistor This ensures that the Zener diode operates within a safe current range.

9. The intelligent control system for an autotransformer-compensated AC constant voltage transformer according to claim 8, characterized in that: The voltage comparison and command output module (300) receives the DC voltage output by the low-voltage AC signal DC conversion module (200), which includes the DC voltage on the grid side and the DC voltage on the load side. The DC voltage on the grid side and the DC voltage on the load side are restored by using the corresponding adjustment multiple in the voltage threshold adjustment and multiplier recording unit (120). Compare and restore the DC voltage on the grid side and the DC voltage on the load side: If the restored DC voltage on the grid side is less than the restored DC voltage on the load side, it is determined that the load side voltage is too high, and a voltage reduction command is output to reduce the restored DC voltage on the load side to the restored DC voltage on the grid side. If the restored grid-side DC voltage is greater than the restored load-side DC voltage, then the load-side voltage is determined to be too low, and a voltage increase command is output to reduce the restored grid-side DC voltage to the restored load-side DC voltage.

Images