AC controller circuit capable of speed regulation and steering control

Abstract

The invention discloses an AC controller circuit capable of speed regulation and steering control, and the circuit comprises a current sampling module which is used for sampling the working current of a motor; the silicon-controlled driving speed regulation module is used for controlling the rotating speed of the motor; the forward and reverse rotation relay control module comprises four groups of relays and controls forward rotation or reverse rotation of the motor through the four groups of relays; the control chip is used for acquiring the working current of the current sampling module and outputting a control signal to the silicon controlled rectifier driving speed regulation module and the forward and reverse rotation relay control module according to the working current; the power supply module provides a high-voltage power supply for driving the relay and a low-voltage power supply for driving the control chip, and the low-voltage power supply is obtained after the high-voltage power supply is processed by the voltage division module; the silicon controlled rectifier driving speed regulation module, the current sampling module and the control chip module share the same grounding point. The device is simple in structure, low in cost and capable of stably controlling operation of the motor.

Description

Technical Field

[0001] The present invention relates to the technical field of motor control, and in particular to an AC controller circuit capable of adjusting speed and controlling steering. Background Art

[0002] A branch chipper is a mechanical device used to process branches and plant waste. It can crush branches and plant waste into powder, which can then be mixed with organic fertilizer to achieve the goal of returning branches to the forest. However, during the shredding process, the branch chipper will inevitably get stuck due to branches being too thick or the tree knots being too hard. The branch chipper needs to reverse and remove the branches to start shredding again. The motors commonly used in branch chippers on the market are AC induction motors and brushless motors. The use of AC series motors is very rare. The use of AC induction motors is relatively expensive and has low starting torque. The control circuit of brushless motors is complex and expensive. AC series motors have the advantages of low cost, high torque, and a wide speed regulation range, but the forward and reverse control circuits are complex. Summary of the Invention

[0003] The purpose of the present invention is to overcome the defect that the circuit for realizing forward and reverse control when using an AC series-excited motor in the prior art branch shredder is relatively complex, and to provide an AC controller circuit with adjustable speed and steering control, which has the advantages of simple structure, low cost and the ability to realize motor forward and reverse rotation and speed regulation.

[0004] The purpose of the present invention is achieved through the following technical solutions: An AC controller circuit capable of adjusting speed and steering control, comprising: Current sampling module, used to sample the working current of the motor; Thyristor drive speed control module, used to control the speed of the motor; The forward and reverse relay control module includes 4 groups of relays, which control the forward or reverse rotation of the motor through the 4 groups of relays; The control chip is used to obtain the working current of the current sampling module and output control signals to the thyristor drive speed control module and the forward and reverse relay control module according to the working current; The power module provides a high-voltage power supply for driving the relay and a low-voltage power supply for driving the control chip. The low-voltage power supply is obtained by processing the high-voltage power supply through the voltage divider module. The thyristor drive speed regulation module, current sampling module and control chip module share the same grounding point.

[0005] Compared to existing technologies, traditional solutions require independent zero-crossing detection circuits for the speed control module. This solution, by sharing a common ground point, allows the control chip to directly process the sampled signals. When existing technologies use multiple independent power supplies, voltage drift between different ground lines can easily cause control signal distortion. This solution eliminates this interference source through unified grounding, and optimized with four relays, reliable forward and reverse control is achieved.

[0006] Preferably, the forward and reverse relay control module includes two comparators, one comparator is connected to the relay responsible for controlling the forward rotation of the motor, and the other comparator is connected to the relay responsible for controlling the reverse rotation of the motor. The comparator is used to ensure that the control chip can still stably drive the relay when the input voltage is unstable.

[0007] Preferably, the positive input terminal of the comparator is connected to the control chip through a resistor, the negative input terminal is connected to the RC step-down circuit, the RC step-down circuit and the high-voltage power supply are directly provided with a voltage regulator tube, and the output terminal controls the on and off of the relay through a switching circuit; the relay includes a forward relay RY1, a forward relay RY2, a reverse relay RY3 and a reverse relay RY4. When the forward relay RY1 and the forward relay RY2 are turned on, the live wire A end of the power supply is connected to the motor winding C end, the neutral wire B end of the power supply is connected to the motor winding D end, and the motor rotates forward; when the reverse relay RY3 and the reverse relay RY4 are turned on, the live wire A end of the power supply is connected to the motor winding D end, the neutral wire B end of the power supply is connected to the motor winding C end, and the motor reverses.

[0008] Preferably, the voltage value range of the negative input terminal of the comparator is that the voltage drop value of the high voltage power supply is greater than 0V and less than 5V.

[0009] Preferably, the current sampling module includes a sampling resistor and an RC filter circuit. The sampling resistor is connected to the RC filter circuit of the thyristor drive speed regulation module at the same time. The RC filter circuit is also connected to the control chip.

[0010] Preferably, the high-voltage power supply is obtained by processing the mains electricity through an RC resistor-capacitor voltage step-down circuit.

[0011] Preferably, the voltage divider module includes a voltage regulator tube and a voltage divider resistor.

[0012] Preferably, the voltage of the high-voltage power supply is 24V, and the voltage of the low-voltage power supply is 5V.

[0013] A branch shredder is provided, which uses an AC controller circuit capable of adjusting speed and direction. The circuit is used to adjust the speed and direction of a motor of the branch shredder.

[0014] The beneficial effects of the present invention are as follows: the AC controller circuit and shredder with adjustable speed and steering control provided herein simplify the control circuit structure of the AC series motor by combining a forward / reverse relay control module with a thyristor-driven speed control module. Simultaneously, a shared grounding point design reduces interference, thereby achieving the motor's forward / reverse rotation and speed regulation functions at a low cost. This solves the problem of complex AC series motor control circuits in the prior art, and has the advantages of simple structure, low cost, and stable control of motor operation. The present invention provides a comparator before the relay, which does not affect high-voltage components such as the chip-driven relay when the load increases and the voltage becomes unstable, thus providing strong anti-interference capabilities. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a circuit principle block diagram of the present invention; Figure 2 It is a specific circuit diagram of the present invention; Figure 3 This is a schematic diagram of the circuit connection of the forward and reverse relay control module of the present invention when it rotates forward; Figure 4 This is a circuit connection diagram of the forward and reverse relay control module of the present invention when it is reversed.

[0016] Among them: 1. Current sampling module, 2. SCR drive speed control module, 3. Forward and reverse relay control module, 4. Control chip, 5. Power supply module. DETAILED DESCRIPTION

[0017] The technical solutions of this application will be described clearly and completely below, in conjunction with the accompanying drawings. It should be understood that the described embodiments represent only a portion of the embodiments of this application, and not all of them. The components of this application, generally described and illustrated in the drawings herein, may be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of this application provided in the drawings is not intended to limit the scope of the claimed application, but rather merely represents selected embodiments of this application. All other embodiments derived by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application. It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings. Furthermore, in the description of this application, the terms "first," "second," etc., are used solely to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0018] In existing technologies, branch chippers using AC series-excited motors face the problem of complex speed regulation and forward and reverse control circuits. Traditional solutions require separate speed regulation and steering control modules, resulting in a large number of circuit components and complex wiring. When handling thick and hard branches, causing the motor to stall, the complex control logic can easily cause signal interference, affecting the timeliness of the reversal action. Such equipment often requires the configuration of independent high and low voltage power supply units, further increasing manufacturing costs.

[0019] To address these issues, designers discovered that coordinated control of speed control signals and steering commands was a key breakthrough in simplifying the circuit. Experiments have verified that eliminating multi-point grounding interference through a unified grounding point allows the control chip to more stably handle dynamic load signals. Dividing the high-voltage power supply to generate a low-voltage power supply not only meets relay drive requirements but also eliminates the need for an additional transformer module. The idea of ​​directly switching winding connections through the relay group stems from a re-examination of the essential requirements of motor phase switching, eliminating the need for multiple intermediate logic conversion steps.

[0020] Therefore, this application proposes an AC controller circuit with adjustable speed and steering control, such as Figure 1-4 As shown, it includes a current sampling module 1, a thyristor drive speed regulation module 2, a forward and reverse relay control module 3 including 4 groups of relays, a control chip 4, and a power supply module 5 that generates a low-voltage power supply by processing a high-voltage power supply by a voltage divider module. The thyristor drive speed regulation module, the current sampling module and the control chip module share the same grounding point.

[0021] The current sampling module measures the motor's operating current through a resistor. This can be implemented using a precision sampling resistor in conjunction with an RC filter circuit, providing real-time load data to the control chip. The thyristor drive speed control module controls the motor's speed by adjusting the conduction angle. This can be implemented using a bidirectional thyristor (TRIAC) and a trigger circuit, acting directly on the motor's main circuit. The forward / reverse relay control module switches the motor's winding connections. This can be achieved by constructing a bridge commutation circuit with four sets of mechanical relays, with the current path altered by the simultaneous operation of two sets of relays. The control chip processes current signals and outputs control commands. This can be achieved using a microcontroller with A / D conversion, coordinating speed and steering according to a pre-set algorithm. The power supply module converts the mains power to the high- and low-voltage components. This can be achieved by using an RC resistor-capacitor voltage-drop circuit in conjunction with a voltage regulator diode to convert the mains power into a 24V relay drive voltage and a 5V chip operating voltage.

[0022] Specifically, when the load current exceeds the threshold during motor operation, the voltage drop across the sampling resistor is filtered and fed into the control chip. The chip then outputs a phase control signal to the thyristor according to a preset program, adjusting the motor speed to prevent overload. When the motor needs to reverse and eject the stuck material, the control chip simultaneously activates two relays to change the winding connection sequence, instantly switching the motor's rotation direction. High and low voltage power supplies are generated through the same RC step-down circuit, and the voltage regulator diode in the voltage divider module ensures voltage stability on the low-voltage side. The ground terminals of all modules are connected to a single ground point during PCB layout to eliminate interference from potential differences between different circuits.

[0023] Compared to existing technologies, traditional solutions require independent zero-crossing detection circuits for the speed control module. This solution, by using a shared ground point, allows the control chip to directly process the sampled signals. When existing technologies use multiple independent power supplies, voltage drift between different ground lines can easily cause control signal distortion. This solution eliminates this interference source through unified grounding. Comparable products on the market typically use eight relays to construct the commutation circuit, but this solution optimizes it to four relays, achieving reliable forward and reverse control.

[0024] Through the above technical solution, this application achieves integrated circuitry for AC series motor speed regulation and steering control, eliminating the signal isolation circuit and independent power supply module required in traditional solutions. The reduced number of relays directly reduces material costs and the probability of failure. The unified grounding point design ensures stable operation even under the vibration conditions of the chipper. The integrated power module reduces the controller size by approximately 40%, making it more suitable for the compact installation space required by the chipper.

[0025] This application further proposes that the forward and reverse relay control module includes two comparators, one comparator is connected to the relay responsible for controlling the forward rotation of the motor, and the other comparator is connected to the relay responsible for controlling the reverse rotation of the motor. The comparator is used to ensure that the control chip can still stably drive the relay when the voltage is unstable.

[0026] A comparator is an electronic device with two inputs and one output, used to compare two voltage signals and output a high or low voltage level. This can be implemented using an operational amplifier or a dedicated voltage comparator chip, which compares a set reference voltage to the input signal. An RC step-down circuit is a circuit consisting of a resistor and a capacitor in series. This circuit can be implemented using a combination of a fixed-resistance metal film resistor and a high-voltage film capacitor. It is used to divide the high-voltage power supply and filter out high-frequency interference. A voltage regulator is a semiconductor device with a voltage stabilization function. This can be implemented using a Zener diode or a TL431 reference source. It is used to establish a stable reference voltage at the end of the RC step-down circuit.

[0027] Specifically, the control signal output by the control chip is connected to the positive input of the comparator through a resistor, while the negative input receives a reference voltage processed by a Zener diode from the high-voltage power supply via an RC step-down circuit. When the high-voltage power supply fluctuates, the Zener diode maintains the reference voltage at the negative input stable, preventing the comparator input level from being affected by power supply fluctuations. When the control chip outputs a high-level signal, the voltage at the comparator's positive input is higher than the reference voltage at the negative input, and the output conducts a switching circuit, closing the relay. When the power supply voltage drops abnormally, the comparator can still correctly determine the control signal level because the reference voltage remains stable, ensuring that the relay drive logic is not affected by power supply fluctuations.

[0028] Compared to existing technologies, traditional relay drive solutions directly connect the control chip output to the relay coil. When the power supply voltage drops, the control signal amplitude decreases, potentially causing the relay to malfunction. This solution uses a comparator to isolate power supply fluctuations from the control signal. This hardware circuitry creates a voltage fluctuation suppression mechanism, improving drive stability without relying on software compensation.

[0029] Through the above technical solution, this application solves the problem of abnormal relay drive signal when the power supply voltage is unstable, ensuring that the relay can still accurately perform on-off operations according to the control signal under voltage fluctuation conditions, avoiding the failure of motor forward and reverse control due to power supply abnormality, and improving the anti-interference ability and operation reliability of the drive system.

[0030] The present application further proposes that the positive input terminal of the comparator is connected to the control chip through a resistor, the negative input terminal is connected to the RC step-down circuit, the RC step-down circuit and the high-voltage power supply are directly provided with a voltage regulator tube, and the output terminal controls the on and off of the relay through a switching circuit; the relay includes a forward relay RY1, a forward relay RY2, a reverse relay RY3 and a reverse relay RY4. When the forward relay RY1 and the forward relay RY2 are turned on, the live wire A end of the power supply is connected to the motor winding C end, the neutral wire B end of the power supply is connected to the motor winding D end, and the motor rotates forward; when the reverse relay RY3 and the reverse relay RY4 are turned on, the live wire A end of the power supply is connected to the motor winding D end, the neutral wire B end of the power supply is connected to the motor winding C end, and the motor reverses.

[0031] The voltage regulator refers to a Zener diode, which can be implemented by a voltage regulator diode with a reverse breakdown voltage of 24V, and is used to suppress the influence of voltage fluctuations of the high-voltage power supply on the reference voltage of the comparator.

[0032] The switching circuit refers to a driving circuit composed of a transistor and a current-limiting resistor. Specifically, it can be implemented by an NPN transistor and a base series resistor, which is used to convert the logic level signal output by the comparator into the driving current required by the relay coil.

[0033] Among them, the symmetrical layout means that the contact connection methods of the forward relay group and the reverse relay group are mirror images of each other. Specifically, this can be achieved by connecting the common contacts of RY1-RY2 to the C and D ends of the motor winding, and connecting the common contacts of RY3-RY4 to the D and C ends, respectively. It is used to directly switch the direction of the winding current by changing the physical connection state of the contacts.

[0034] Specifically, when the control chip outputs a forward rotation signal, the comparator's positive input voltage exceeds the negative input reference voltage, outputting a high level and conducting the switch circuit. This energizes the RY1-RY2 relay coil, energizing the hot wire (A) to the motor's C winding via the RY1 normally-open contact, and the neutral wire (B) to the D winding via the RY2 normally-open contact. This creates a C-to-D current path, driving the motor forward. If the power supply voltage fluctuates, the Zener diode maintains a stable negative input reference voltage by absorbing overvoltage energy in the RC step-down circuit, preventing the relay from tripping due to insufficient drive voltage. When reverse rotation is required, the control chip switches the output signal to activate the other comparator. After the RY3-RY4 relay is closed, the hot wire (A) is reconnected to the D winding, and the neutral wire (B) is reconnected to the C winding, forming a D-to-C current path, enabling reverse rotation of the motor.

[0035] Compared with the existing technology, the forward and reverse control of traditional AC series-excited motors requires the use of a mechanical reversing switch or two sets of independent drive circuits. When the mechanical contacts are switched, arcs are easily generated, resulting in poor contact. The symmetrical layout of the relay directly switches the winding polarity by changing the physical connection state of the contacts, avoiding contact wear caused by repeated operation of the reversing switch; in the existing technology, the relay drive circuit directly uses the control chip output signal to drive the coil. When the power supply voltage drops, insufficient drive current is likely to occur, resulting in contact jitter. However, the reference voltage comparison structure composed of a comparator, an RC step-down circuit, and a voltage regulator tube can maintain the stability of the relay drive signal when the power supply voltage fluctuates.

[0036] Through the above technical solution, the present application can directly complete the motor winding polarity switching with a symmetrical contact layout of four relays, eliminating the contact wear problem of the mechanical reversing switch; through the combined structure of the comparator and the voltage regulator tube, the stability of the relay drive signal is ensured when the power supply voltage fluctuates, avoiding contact malfunction caused by voltage drop; through the switching circuit, the control signal and the high-voltage circuit are electrically isolated, reducing the risk of electromagnetic interference to the control chip.

[0037] The present application further proposes that the voltage value range of the negative input terminal of the comparator is a voltage drop value of the high voltage power supply greater than 0V and less than 5V.

[0038] Specifically, when the high-voltage power supply voltage drops due to a sudden load change or mains power fluctuation, the reference voltage at the negative input of the comparator decreases synchronously through the synergistic action of the RC step-down circuit and the voltage regulator diode, maintaining a voltage difference greater than 0V and less than 5V with the high-voltage power supply. At this time, the positive input of the comparator receives a command signal from the control chip. Due to the automatic adjustment of the reference voltage at the negative input, the relative difference between the command signal and the reference voltage remains stable. This dynamic balancing mechanism ensures that even if the high-voltage power supply voltage fluctuates within the allowable range, the comparator can still accurately determine the level of the control signal, thereby preventing false triggering of the relay due to power supply fluctuations. The voltage difference range is set by taking into account the common-mode range of the comparator input and the relay drive voltage requirements. For example, when the high-voltage power supply is 24V, the reference voltage can be maintained in the range of 19-24V. In this embodiment, the input voltage at the secondary input of the comparator can be 21.9V.

[0039] Compared to existing technologies, traditional solutions typically use a fixed reference voltage source to provide a benchmark for the comparator. When the power supply voltage fluctuates, the difference between the control signal and the reference voltage can exceed the threshold range, causing the relay to malfunction. However, this solution establishes a linkage mechanism between the reference voltage and the power supply voltage. This ensures that the relative relationship between the control signal and the reference voltage is not affected by fluctuations in the absolute voltage value, thus maintaining the reliability of the relay control logic even under unstable power supply conditions.

[0040] Through the above technical solution, this application effectively eliminates interference from power supply voltage fluctuations on relay control signals, ensuring that when the shredder encounters sudden load changes that cause power supply fluctuations, the motor forward and reverse switching instructions can still be accurately executed, avoiding equipment jamming or control failure caused by relay misoperation. This technical solution is particularly suitable for the control system of shredders using AC series motors, improving the reliability of equipment operation while maintaining a low cost advantage.

[0041] This application further proposes a technical solution in which the current sampling module includes a sampling resistor and an RC filter circuit, the sampling resistor is simultaneously connected to the RC filter circuit of the thyristor drive speed regulation module, and the RC filter circuit is also connected to the control chip.

[0042] The sampling resistor is a precision resistor connected in series in the motor's main circuit. Specifically, it can be a 0.05Ω alloy resistor. It converts the motor's operating current into a voltage signal. Its purpose is to directly obtain the physical quantity of the load current, providing basic detection parameters for closed-loop speed regulation.

[0043] The RC filter circuit is a low-pass filter network composed of resistors and capacitors. Specifically, it can be implemented using a 1kΩ resistor and a 0.1μF capacitor. Its cutoff frequency must be set below 20 times the thyristor trigger frequency. This circuit forms a shared noise suppression path between the sampling resistor and the thyristor driver module, effectively eliminating the impact of high-frequency interference generated by the thyristor's on-off switching on the sampled signal.

[0044] Specifically, the voltage signal generated across the sampling resistor is connected in parallel to the RC filter circuit of the thyristor driver module, forming a dual filtering mechanism. In the signal transmission path, high-frequency interference components are first attenuated by the filter circuit on the thyristor driver module side, and the remaining low-frequency signal is then processed secondary by the RC filter circuit of the current sampling module. This shared filtering structure avoids the phase discrepancy caused by separate filtering in the sampling and drive circuits in traditional solutions, while also reducing the reuse of filtering components. The purified current signal is directly transmitted to the A / D conversion port of the control chip, ensuring the time domain consistency and amplitude accuracy of the current feedback signal.

[0045] The present application further proposes that the high voltage power supply is obtained by processing the mains electricity through an RC resistor-capacitor voltage step-down circuit.

[0046] Among them, the RC resistor-capacitor step-down circuit refers to an AC voltage conversion network composed of resistors and capacitors. It can be specifically implemented by using a polyester film capacitor and a metal film resistor connected in series, using the capacitive reactance characteristics of the capacitor to form an impedance voltage divider for the AC current.

[0047] Among them, mains electricity refers to the power supply directly connected to the 220V or 380V AC power grid, which can be implemented using a two-wire input method, eliminating the intermediate voltage transformation link to achieve direct power supply.

[0048] Specifically, a capacitor is connected in series in the mains live wire circuit to form a capacitive reactance, while a resistor is connected in parallel behind the capacitor to form a voltage divider. When AC power passes through the capacitor, the capacitive reactance generated by the capacitor and the resistance of the resistor form a fixed-proportional voltage divider, which reduces the high-voltage mains voltage to the target voltage range. By adjusting the matching relationship between capacitor capacitance and resistance value, this circuit can adapt to the stable voltage reduction requirements under varying input voltage fluctuations. It also eliminates the iron core and winding structure of a traditional transformer, significantly reducing the size and weight of the power module.

[0049] Through the above technical solution, the present application solves the problem of complex and high-cost high-voltage power supply structure, realizes the direct conversion of AC mains power to the high-voltage power supply required by the control circuit, simplifies the power module structure by about 50%, reduces the material cost by about 60%, and avoids the interference of electromagnetic noise during the operation of the transformer on the signal acquisition of the control chip.

[0050] The present application further proposes that the voltage divider module includes a voltage regulator tube and a voltage divider resistor.

[0051] The present application further proposes that the voltage of the high-voltage power supply is 24V and the voltage of the low-voltage power supply is 5V.

[0052] The high-voltage power supply refers to the 24V DC power output after processing through an RC resistor-capacitor voltage-step-down circuit. This circuit can be implemented using a combination of a resistor-capacitor voltage-step-down circuit and rectifier-filter components, and is used to drive the forward and reverse relay control module. The low-voltage power supply refers to the 5V DC power output from the high-voltage power supply after processing through a voltage divider module. This can be implemented using a series circuit of a voltage-stabilizing diode and a voltage-dividing resistor, and is used to provide the operating voltage for the control chip. The voltage-dividing module is a step-down circuit consisting of a voltage-stabilizing diode and a resistor. This can be implemented by connecting a voltage-stabilizing diode in parallel at the high-voltage power supply output and grounding it through a voltage-dividing resistor. Its function is to convert the 24V high-voltage power supply into a stable 5V low-voltage output.

[0053] Specifically, the 24V high-voltage power supply is attenuated by the voltage-dividing resistor and zener diode in the voltage-dividing module. The voltage across the zener diode is clamped to 5V. This 5V voltage is directly supplied to the control chip as an operating power source, while the undivided 24V voltage is used to drive the relay coil. Since relay driving requires a higher voltage to ensure electromagnetic attraction, the 24V setting satisfies this requirement. The control chip uses a standardized 5V power supply, compatible with universal logic level interfaces. The voltage-dividing module simultaneously maintains high voltage and generates low voltage through a single circuit, avoiding the component redundancy associated with separate step-down circuits.

[0054] Through the above technical solution, this application achieves precise matching of high-voltage and low-voltage power supplies, ensuring the coordinated operation of the relay drive voltage and the control chip operating voltage. The integrated design of the voltage divider module reduces the number of components in the power circuit, reducing hardware costs and assembly difficulty. The clear 24V and 5V parameter settings standardize component selection and improve the reliability and maintainability of the circuit.

[0055] The present application further proposes a branch chipper, which uses an AC controller circuit with adjustable speed and direction control, and the circuit is used to adjust the speed and direction of the branch chipper motor.

[0056] Among them, the AC controller circuit with adjustable speed and steering control refers to a circuit system that includes motor winding commutation control and power regulation functions. It can be implemented by a composite circuit structure including a relay group and a thyristor. The forward and reverse control is achieved by switching the relay contacts to change the connection sequence of the motor windings, and stepless speed regulation is achieved by adjusting the conduction angle of the thyristor.

[0057] Specifically, when the chipper is handling thick branches or branches with hard knots, the current sampling module monitors changes in the motor load in real time, and the control chip determines whether a jam has occurred based on a preset threshold. If an abnormally high current is detected, a control signal triggers the relay group in the forward and reverse relay control module to switch the connection mode, reversing the motor winding phase and achieving instantaneous blade retraction. Simultaneously, the thyristor drive speed control module dynamically adjusts the conduction angle based on the actual load, maintaining a high speed during the normal chipping phase to improve efficiency and reducing the speed during the retraction phase to protect the mechanical structure.

[0058] In some specific embodiments, the relay group can use a four-contact electromagnetic relay to form an H-bridge circuit, the thyristor can use a bidirectional thyristor with a resistor-capacitor buffer circuit, and the control chip can use a microcontroller with an ADC interface to realize digital processing of the current signal.

[0059] Compared to existing technologies, most existing chippers use a separate motor drive module and a mechanical commutation mechanism for reversing, which increases the size of the device and poses a risk of mechanical wear. This solution, however, integrates power electronics and relay control functions into a single control circuit, directly replacing the mechanical commutation mechanism with electronic commutation. This reduces the size and maintenance requirements of the device while ensuring reliability.

[0060] Through the above technical solution, this application can achieve millisecond-level automatic reversal response when the branch chipper encounters a jam, effectively avoiding motor stall damage; by replacing the mechanical speed change mechanism with electronic speed regulation, the equipment can automatically adjust the crushing strength according to the hardness of the material; and use standard relays and thyristor devices to build a control circuit, which can reduce the hardware cost by about 40% compared to the brushless motor drive solution.

[0061] The present application further proposes an AC controller circuit with adjustable speed and direction control, which is used to adjust the speed and direction of the branch chipper motor.

[0062] Among them, the AC controller circuit refers to an integrated circuit system including a thyristor drive speed control module, a forward and reverse relay control module and a control chip. It can be implemented by combining a bidirectional thyristor and a relay array, and the speed is achieved by adjusting the conduction angle by outputting a pulse signal from the control chip.

[0063] Among them, the forward and reverse relay control module refers to a motor winding switching unit composed of four groups of electromagnetic relays. It can be implemented by a combination of two groups of normally open contacts and two groups of normally closed contacts. The forward and reverse switching is achieved by changing the connection position of the power live wire and the neutral wire in the motor winding.

[0064] Among them, the voltage-dividing power supply module refers to a power supply unit that converts high-voltage AC power into low-voltage DC power. Specifically, it can be implemented by using an RC resistor-capacitor voltage-step-down circuit in conjunction with a voltage-stabilizing diode. The 24V high voltage is converted into a 5V low voltage to supply the control chip through a series voltage-dividing resistor.

[0065] Among them, the shared grounding point means that the ground terminals of the speed regulation module, sampling module and control chip are physically and directly connected. Specifically, it can be achieved by using a single-point grounding wiring method, which improves signal stability by eliminating the potential difference interference caused by multiple-point grounding.

[0066] Specifically, when the chipper encounters a blockage, the control chip generates a reverse command based on the abnormal current value detected by the current sampling module. Two sets of relays in the forward / reverse relay control module disconnect the forward circuit, while the other two sets of relays close to form a reverse circuit, reversing the direction of the motor winding current. During this process, the thyristor drive speed control module adjusts the conduction angle according to preset speed parameters to control the motor speed during reverse rotation. The power supply module converts the mains power into a high-voltage 24V drive relay coil through a resistor-capacitor step-down circuit. This voltage is then divided by a voltage regulator diode to generate 5V DC power for the control chip, achieving an integrated design of high and low voltage circuits.

[0067] Compared with the existing technology, the forward and reverse control of traditional AC series-excited motors requires the independent setting of two sets of interlocking contactors and complex logic circuits, while this solution simplifies the winding switching path through a four-relay combination structure; the speed regulation and steering control in the existing technology use separate power supply systems, while this solution realizes the integrated processing of a single power supply through a voltage-dividing power supply module; the motor protection function in the existing technology requires an additional overcurrent detection device, while this solution realizes adaptive reverse control through the collaborative processing of the current sampling module and the control chip.

[0068] Through the above technical solution, the present application can detect the motor load status in real time during the operation of the branch chipper, and automatically trigger the reverse action and maintain the set speed when encountering a jam, avoiding the operational delay of manual steering in the traditional solution; replacing the mechanical contactor group with a four-relay switching structure reduces the failure rate caused by contact wear; and adopting a shared grounding point design eliminates ground interference between multiple modules, so that the control chip can still stably output the drive signal when the voltage fluctuates.

[0069] The above description is merely an embodiment of the present application and is not intended to limit the scope of protection of the present application. For those skilled in the art, various modifications and variations of the present application are possible. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. An AC controller circuit with adjustable speed and steering control, characterized in that: include: Current sampling module, used to sample the working current of the motor; Thyristor drive speed control module, used to control the speed of the motor; The forward and reverse relay control module includes 4 groups of relays, which control the forward or reverse rotation of the motor through the 4 groups of relays; The control chip is used to obtain the working current of the current sampling module and output control signals to the thyristor drive speed control module and the forward and reverse relay control module according to the working current; The power module provides a high-voltage power supply for driving the relay and a low-voltage power supply for driving the control chip. The low-voltage power supply is obtained by processing the high-voltage power supply through the voltage divider module. The thyristor drive speed regulation module, current sampling module and control chip module share the same grounding point.

2. The AC controller circuit with adjustable speed and steering control according to claim 1, characterized in that: The forward and reverse relay control module includes two comparators, one comparator is connected to the relay responsible for controlling the forward rotation of the motor, and the other comparator is connected to the relay responsible for controlling the reverse rotation of the motor. The comparator is used to ensure that the control chip can still stably drive the relay when the input voltage is unstable.

3. The AC controller circuit with adjustable speed and steering control according to claim 2, characterized in that: The positive input end of the comparator is connected to the control chip through a resistor, and the negative input end is connected to the RC step-down circuit. The RC step-down circuit and the high-voltage power supply are directly provided with a voltage regulator tube, and the output end controls the on and off of the relay through a switch circuit; the relay includes a forward relay RY1, a forward relay RY2, a reverse relay RY3 and a reverse relay RY4. When the forward relay RY1 and the forward relay RY2 are turned on, the live wire A end of the power supply is connected to the motor winding C end, the neutral wire B end of the power supply is connected to the motor winding D end, and the motor rotates forward; when the reverse relay RY3 and the reverse relay RY4 are turned on, the live wire A end of the power supply is connected to the motor winding D end, the neutral wire B end of the power supply is connected to the motor winding C end, and the motor reverses.

4. The AC controller circuit with adjustable speed and steering control according to claim 3, characterized in that: The voltage value range of the negative input terminal of the comparator is that the voltage drop value of the high voltage power supply is greater than 0V and less than 5V.

5. The AC controller circuit with adjustable speed and steering control according to claim 1, characterized in that: The current sampling module includes a sampling resistor and an RC filter circuit. The sampling resistor is connected to the RC filter circuit of the thyristor drive speed regulation module at the same time. The RC filter circuit is also connected to the control chip.

6. The AC controller circuit with adjustable speed and steering control according to claim 1, characterized in that: The high voltage power supply is obtained by processing the mains electricity through an RC resistor-capacitor voltage step-down circuit.

7. The AC controller circuit with adjustable speed and steering control according to claim 6, characterized in that: The voltage dividing module includes a voltage-stabilizing tube and a voltage-dividing resistor.

8. The AC controller circuit with adjustable speed and steering control according to claim 6, characterized in that: The voltage of the high-voltage power supply is 24V, and the voltage of the low-voltage power supply is 5V.

9. A branch chipper, characterized in that: An AC controller circuit with adjustable speed and direction control as described in any one of claims 1 to 8 is used to adjust the speed and direction of a branch chipper motor.

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