Electronic expansion valve controller with fluid control algorithm

Abstract

The utility model provides an electronic expansion valve controller with a fluid control algorithm. The electronic expansion valve controller comprises a signal acquisition module, a control processing module and an output driving module, wherein the signal acquisition module comprises a sensor interface and is used for acquiring corresponding temperature signals and pressure signals and transmitting the acquired signals to the control processing module; the control processing module is connected with the signal acquisition module and is used for calling a proportion-integration-differentiation (PID) control algorithm to generate a target control signal based on the temperature signal and the pressure signal acquired by the signal acquisition module and target control parameters corresponding to different refrigerants and control modes; and the output driving module is in signal connection with the control processing module and is used for receiving the target control signal output by the control processing module and converting the target control signal into a driving signal for driving an electronic expansion valve.

Description

Technical Field

[0001] This utility model relates to an electronic expansion valve controller equipped with a fluid control algorithm. Background Technology

[0002] In many industries, such as HVAC, refrigeration systems, and water treatment facilities, there are stringent requirements for the stability and efficiency of fluid systems. Traditional electronic expansion valve controllers, due to their limited control precision, struggle to achieve ideal control results when facing complex operating conditions.

[0003] Therefore, there is an urgent need for a new type of electronic expansion valve controller that can adapt to various working conditions and achieve precise adjustment. Summary of the Invention

[0004] To address the technical problem of limited control accuracy in existing traditional electronic expansion valve controllers, which makes it difficult to achieve ideal control results under complex operating conditions, an electronic expansion valve controller with a fluid control algorithm is proposed. By collecting various temperature and pressure signals and calling a PID algorithm corresponding to the refrigerant and control mode to generate control signals to drive the electronic expansion valve, dynamic control requirements that can adapt to different refrigerants and control modes are achieved. This improves the response speed and control accuracy of the electronic expansion valve opening adjustment and is suitable for various operating scenarios such as single system, dual system, and liquid / air injection.

[0005] The technical solution of this utility model is: an electronic expansion valve controller with a fluid control algorithm, characterized in that it includes: a signal acquisition module, a control processing module, and an output drive module; wherein:

[0006] The signal acquisition module includes a sensor interface, which includes at least one of an intake temperature interface, a low-pressure interface, and an exhaust temperature interface, for acquiring corresponding temperature and pressure signals and transmitting the acquired signals to the control processing module.

[0007] The control processing module is connected to the signal acquisition module and is used to generate a target control signal by calling the proportional-integral-derivative PID control algorithm based on the temperature signal and pressure signal acquired by the signal acquisition module and the target control parameters corresponding to different refrigerants and control modes.

[0008] The output drive module is signal-connected to the control processing module and is used to receive the target control signal output by the control processing module and convert the target control signal into a drive signal for driving the electronic expansion valve.

[0009] In one optional embodiment, the signal acquisition module further includes analog signal channels corresponding one-to-one with the sensor interfaces, used to transmit the output signals of the corresponding sensors;

[0010] The analog signal channel includes a signal filtering unit and an anti-interference unit;

[0011] The signal filtering unit includes at least one low-pass filter;

[0012] The anti-interference unit includes an isolation power supply, a transient voltage suppression TVS diode, and / or a common-mode inductor.

[0013] In one optional embodiment, the sensor interface employs a hot-swappable connection structure, including a multi-pin socket with resilient contacts and a corresponding plug;

[0014] The signal filtering unit and the anti-interference unit are integrated in the same signal conditioning circuit board, which is connected to the sensor interface via a plug-in method.

[0015] In an optional embodiment, the signal acquisition module further includes an identification control unit, which is used to detect the identification parameters of the sensor when the sensor is connected, convert the identification parameters into a corresponding sensor type identifier, and output the sensor type identifier to the control processing module;

[0016] After receiving the sensor type identifier, the control processing module calls the signal processing path that matches the sensor to obtain the temperature signal and pressure signal.

[0017] In one optional embodiment, the signal acquisition module further includes an expansion interface unit for connecting to an external analog-to-digital converter, frequency-to-voltage converter, and / or serial protocol adapter for accessing sensors of different standards.

[0018] In one optional embodiment, the output drive module includes two electronic expansion valve control channels for connecting to two electronic expansion valves respectively.

[0019] The electronic expansion valve control channel includes a feedback detection unit and a drive signal switching unit;

[0020] The feedback detection unit is used to detect the voltage or current feedback value corresponding to the target control signal;

[0021] The drive signal switching unit is at least one of a DIP switch, a jumper structure, or an automatic switching mechanism controlled by the control processing module.

[0022] In one optional embodiment, the control processing module includes a control mode register unit and a mode invocation unit;

[0023] The control mode register unit is used to register parameter groups of preset multiple control modes, including at least one of pressure control mode, temperature and pressure combined control mode, constant temperature balance control mode, liquid injection control mode and jet injection control mode.

[0024] The mode calling unit is used to call the parameter group of the corresponding control mode according to the analog quantity type and system pipeline unit type obtained by the signal acquisition module.

[0025] In one optional embodiment, the controller further includes a display interaction module, comprising a number display unit and an input unit;

[0026] The display unit includes a digital tube and / or a liquid crystal display;

[0027] The input unit includes buttons, knobs, and / or dials.

[0028] In an optional embodiment, the controller further includes a communication module for communicating with external devices, including at least one of an RS485 communication unit, a controller area network (CAN) communication unit, an Ethernet communication unit, and a 4G communication unit.

[0029] In one optional embodiment, the controller includes a controller housing and a control board disposed inside the housing;

[0030] The controller housing is made of fire-resistant material and supports rail mounting. The front panel of the controller housing is made of acrylic material, and the exterior of the housing is equipped with a heat dissipation structure.

[0031] The control board is powered by an isolated power supply.

[0032] The beneficial effects of this utility model are as follows:

[0033] 1. The control processing module of this utility model can call the target control parameters corresponding to different refrigerants and control modes, execute the proportional-integral-derivative PID control algorithm, improve the adaptability and accuracy of control, and adapt to a variety of complex operating conditions.

[0034] 2. By setting up multiple sensor interfaces, including temperature and pressure acquisition interfaces, and combining them with filtering and anti-interference structures in the analog signal channel, the stability and anti-interference capability of signal acquisition are improved.

[0035] 3. The output drive module supports a dual-channel structure. Each channel is equipped with a feedback detection and drive switching unit, which can control two electronic expansion valves respectively. It is suitable for single-system or dual-system pipeline configurations.

[0036] 4. The controller has multiple control modes, including pressure control, combined temperature and pressure control, constant temperature balance control, liquid spray control and jet spray control, which can flexibly match the system operating status and application requirements.

[0037] 5. The display and interaction module includes a digital tube display and input structures such as buttons and knobs, which facilitates parameter configuration and status reading for users.

[0038] 6. The controller integrates multiple communication methods, including RS485, CAN, Ethernet and 4G communication modules, enhancing compatibility with external devices and system integration capabilities.

[0039] 7. The controller housing is made of fire-resistant material, supports rail mounting, and is equipped with a heat dissipation structure. The front panel is made of acrylic material, and the internal control board is powered by an isolated power supply. The overall safety and reliability are high, making it suitable for long-term operation in industrial environments. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the structure of an electronic expansion valve controller with a fluid control algorithm according to the present invention.

[0041] Figure 2 This is another structural schematic diagram of an electronic expansion valve controller with a fluid control algorithm according to the present invention.

[0042] Figure 3 This is a topology diagram of an electronic expansion valve controller with a fluid control algorithm according to the present invention. Detailed Implementation

[0043] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. This embodiment is based on the technical solution of the present invention and provides detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following embodiments.

[0044] In this invention, the terms "in one possible embodiment," "exemplary," or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "in one possible embodiment," "exemplary," or "for example" in this invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "in one possible embodiment," "exemplary," or "for example" is intended to present the relevant concepts in a specific manner.

[0045] In many industries, such as HVAC, refrigeration systems, and water treatment facilities, there are stringent requirements for the stability and efficiency of fluid systems. Traditional electronic expansion valve controllers, due to their limited control precision, struggle to achieve ideal control results under complex operating conditions. Therefore, developing a new type of electronic expansion valve controller capable of adapting to various operating conditions and achieving precise adjustment has become an urgent need.

[0046] like Figure 1 As shown, an electronic expansion valve controller 10 with a fluid control algorithm includes: a signal acquisition module 101, a control processing module 102, and an output drive module 103; wherein:

[0047] The signal acquisition module includes a sensor interface, which includes at least one of an intake temperature interface, a low-pressure interface, and an exhaust temperature interface, for acquiring corresponding temperature and pressure signals and transmitting the acquired signals to the control processing module.

[0048] The control processing module is connected to the signal acquisition module and is used to generate a target control signal by calling the proportional-integral-derivative PID control algorithm based on the temperature signal and pressure signal acquired by the signal acquisition module and the target control parameters corresponding to different refrigerants and control modes.

[0049] The output drive module is signal-connected to the control processing module and is used to receive the target control signal output by the control processing module and convert the target control signal into a drive signal for driving the electronic expansion valve.

[0050] For example, the control processing module can have refrigerant identification and pressure-enthalpy diagram matching functions, and can automatically convert the current pressure to saturation temperature and calculate superheat according to different types of refrigerants. The controller can have a segmented superheat control algorithm, which can set different target superheats according to the ambient temperature zones to adapt to complex scenarios such as high or low temperatures. In addition, the controller can have high superheat alarm and low superheat alarm functions, and the alarm logic is based on the time when the superheat continuously exceeds the threshold.

[0051] In addition, in the PID control algorithm, the proportional, integral, and derivative coefficients can be set via the front panel buttons and stored in the controller's built-in EEPROM register area.

[0052] In one optional embodiment, the signal acquisition module further includes analog signal channels corresponding one-to-one with the sensor interfaces, used to transmit the output signals of the corresponding sensors;

[0053] The analog signal channel includes a signal filtering unit and an anti-interference unit;

[0054] The signal filtering unit includes at least one low-pass filter;

[0055] The anti-interference unit includes an isolation power supply, a transient voltage suppression TVS diode, and / or a common-mode inductor.

[0056] For example, the signal filtering unit can be used to filter out interference components such as electrical noise, high-frequency jitter, or transient spikes in the acquired signal, improving the stability and accuracy of the sampled data. The anti-interference unit can be used to suppress external electromagnetic interference, crosstalk introduced by sensor wiring, and other interference sources, ensuring the integrity and identifiability of the weak current analog signal during transmission. This ensures that the temperature and pressure signals read by the controller have a high signal-to-noise ratio, avoids control misjudgments, improves the accuracy of the PID control algorithm response, prevents frequent output changes or abnormal opening due to error jitter, and meets the basic requirements for anti-interference capability and operational stability in industrial environments.

[0057] For example, the signal filtering unit may include an RC low-pass filter or an inductor-capacitor composite filter network, and the anti-interference unit may include an optocoupler isolator, a common-mode choke, or a shielded grounding structure, which may be located between each sensor interface and the input terminal of the signal acquisition module.

[0058] In one optional embodiment, the sensor interface employs a hot-swappable connection structure, including a multi-pin socket with resilient contacts and a corresponding plug;

[0059] The signal filtering unit and the anti-interference unit are integrated in the same signal conditioning circuit board, which is connected to the sensor interface via a plug-in method.

[0060] For example, a hot-swappable connection structure may include a multi-pin socket with resilient contacts and a corresponding plug, and the plug structure has a ground pin priority contact design to improve interface connection reliability.

[0061] In an optional embodiment, the signal acquisition module further includes an identification control unit, which is used to detect the identification parameters of the sensor when the sensor is connected, convert the identification parameters into a corresponding sensor type identifier, and output the sensor type identifier to the control processing module;

[0062] After receiving the sensor type identifier, the control processing module calls the signal processing path that matches the sensor to obtain the temperature signal and pressure signal.

[0063] For example, when a user inserts a temperature or pressure sensor, its model, signal output type (analog / digital), and electrical standard (voltage / current) can be automatically identified, and the controller can automatically select or adjust the sampling rate, filtering parameters, PID coefficients, etc. accordingly.

[0064] In one optional embodiment, the signal acquisition module further includes an expansion interface unit for connecting to an external analog-to-digital converter, frequency-to-voltage converter, and / or serial protocol adapter for accessing sensors of different standards.

[0065] For example, the expansion interface unit can be used to identify the sensor type based on the resistance, voltage level, or communication handshake signal of the connected sensor and invoke the corresponding acquisition strategy. It can support compatible connections with external analog-to-digital converters, frequency-to-voltage converters, or serial protocol adapters. For instance, when a user inserts a temperature or pressure sensor, if it is a third-party non-standard interface sensor, the expansion interface unit works in conjunction with an external protocol conversion module to complete the connection.

[0066] In one optional embodiment, the output drive module includes two electronic expansion valve control channels for connecting to two electronic expansion valves respectively.

[0067] The electronic expansion valve control channel includes a feedback detection unit and a drive signal switching unit;

[0068] The feedback detection unit is used to detect the voltage or current feedback value corresponding to the target control signal;

[0069] The drive signal switching unit is at least one of a DIP switch, a jumper structure, or an automatic switching mechanism controlled by the control processing module.

[0070] For example, the electronic expansion valve control channel may also include a pulse drive circuit for receiving the target opening signal output by the control processing module and converting the control signal into a pulse signal (e.g., a step signal). For example, the target opening signal may be converted into current pulses of a corresponding number, frequency, and direction, thereby controlling the step forward or backward movement of the electronic expansion valve opening, precisely adjusting the valve opening, and driving the stepping electronic expansion valve.

[0071] The feedback detection unit can be used to detect the structure of the actual output signal and the actuator feedback value. It can be a combination of current loop feedback, voltage monitoring, Hall effect devices, etc. It can collect the execution status of the drive signal in real time, such as: whether the actual output current reaches the target; whether the control signal is transmitted normally; whether the valve is stuck or locked. It provides feedback data to the control processing module or for human-machine interaction display, forming part of the closed-loop control.

[0072] The drive signal switching unit can manually or automatically switch the drive signal type or output mode settings. Hardware-wise, it can be configured as a DIP switch / jump switch, or the control processing module can automatically switch between them. This allows the controller to adapt to electronic expansion valves of different brands and signal standards, selecting voltage drive mode in some situations and current drive mode in others, or switching between unidirectional / bidirectional drive and different control logics.

[0073] In one optional embodiment, the control processing module includes a control mode register unit and a mode invocation unit;

[0074] The control mode register unit is used to register parameter groups of preset multiple control modes, including at least one of pressure control mode, temperature and pressure combined control mode, constant temperature balance control mode, liquid injection control mode and jet injection control mode.

[0075] The mode calling unit is used to call the parameter group of the corresponding control mode according to the analog quantity type and system pipeline unit type obtained by the signal acquisition module.

[0076] For example, the controller may be adaptable to different refrigerants and have multiple control modes, such as pressure control, combined temperature and pressure control, constant temperature balance control, liquid injection control, and jet injection control.

[0077] In one optional embodiment, the controller further includes a display interaction module, comprising a number display unit and an input unit;

[0078] The display unit includes a digital tube and / or a liquid crystal display;

[0079] The input unit includes buttons, knobs, and / or dials.

[0080] For example, the display unit can be a standard 7-segment 4-digit LED display, supporting the display of parameters, menus, fault codes, and operating status switching. The input unit can be equipped with 3 function buttons and 1 parameter knob or selection dial. Through the combination of the digital display, buttons, and knob or dial, a user-friendly human-machine interface is achieved.

[0081] In addition, the display unit may be equipped with buttons and menus for selecting refrigerant type and control mode. The control processing module calls preset parameter groups according to the selection results to adapt to different refrigerants and control logic.

[0082] In an optional embodiment, the controller further includes a communication module for communicating with external devices, including at least one of an RS485 communication unit, a controller area network (CAN) communication unit, an Ethernet communication unit, and a 4G communication unit.

[0083] In addition, the controller can support multiple control protocols such as Modbus RTU (Modbus Remote Terminal Unit Protocol) and Modbus TCP / IP (Modbus Transmission Control Protocol / Internet Protocol).

[0084] In one optional embodiment, the controller includes a controller housing and a control board disposed inside the housing;

[0085] The controller housing is made of fire-resistant material and supports rail mounting. The front panel of the controller housing is made of acrylic material, and the exterior of the housing is equipped with a heat dissipation structure.

[0086] The control board is powered by an isolated power supply.

[0087] For example, the controller housing can be a metal structure with fireproof, waterproof, and dustproof functions, and the communication and power interfaces are arranged on different sides to avoid crosstalk. In addition, the controller can be installed on a DIN rail, the control board uses an isolated power supply, the housing has a heat dissipation structure, and the front panel is made of acrylic material to improve display clarity.

[0088] In this embodiment, through the above structure, the control processing module of this utility model can call the target control parameters corresponding to different refrigerants and control modes, execute the proportional-integral-derivative PID control algorithm, improve the adaptability and accuracy of the control, and adapt to various complex operating conditions. By setting multiple sensor interfaces, including temperature and pressure acquisition interfaces, and combining the filtering and anti-interference structure in the analog signal channel, the stability and anti-interference capability of signal acquisition are improved. The output drive module supports a dual-channel structure, with each channel equipped with a feedback detection and drive switching unit, which can control two electronic expansion valves separately, suitable for single-system or dual-system pipeline configurations. The controller has multiple control modes, including pressure control, temperature and pressure combined control, constant temperature balance control, liquid injection control, and air jet control, which can flexibly match the system operating status and application requirements. The display and interaction module includes a digital tube display and input structures such as buttons and knobs, which facilitates parameter configuration and status reading for users. The controller integrates multiple communication methods, including RS485, CAN, Ethernet, and 4G communication modules, enhancing compatibility with external devices and system integration capabilities. The controller housing is made of fire-resistant material, supports rail mounting, and is equipped with a heat dissipation structure. The front panel is made of acrylic material, and the internal control board is powered by an isolated power supply. It has high overall safety and reliability and is suitable for long-term operation in industrial environments.

[0089] Figure 2 This is another structural schematic diagram of an electronic expansion valve controller with a fluid control algorithm according to the present invention. Figure 3This is a topology diagram of an electronic expansion valve controller with a fluid control algorithm according to this utility model. In one possible implementation, such as... Figure 2 , Figure 3 As shown, the controller body consists of multiple functional modules, which work together to control flow.

[0090] The controller features multi-channel analog signal acquisition, capable of acquiring multiple key temperature points on the pipeline, such as intake temperature and low-pressure. The controller acquires information through multiple sensor interfaces, such as… Figure 2 The diagram shows pressure acquisition modules, temperature acquisition modules, current acquisition modules, and voltage acquisition modules. Sensor interfaces may include intake temperature, low-pressure, and exhaust temperature acquisition modules, and the acquired information is used in the controller software to calculate control variables. The controller employs multi-variable collaborative control, which can combine the inherent relationships between various controlled objects to find the globally optimal solution.

[0091] The controller can drive peripheral devices (such as electronic expansion valves, relays, etc.) through output modules for actual control. Output modules can include electronic expansion valve start modules, output relay modules, analog output modules, etc. Specifically, the controller controls fluid flow by adjusting the opening of the electronic expansion valves in the pipeline, and can control up to two electronic expansion valves simultaneously, meeting the needs of most single / dual system pipelines.

[0092] The controller can employ a proportional-integral-derivative (PID) control algorithm for pipeline fluid control, enabling rapid response to setpoint changes while minimizing overshoot and steady-state error. Specifically, the controller offers two PID control algorithms: typical PID control and adaptive gain-adjustable PID. Typical PID control involves manually setting the proportional, integral, and derivative parameters, providing greater control over the system. Adaptive gain-adjustable PID dynamically adjusts the P, I, and D parameters based on current operating conditions, maintaining good control performance under varying conditions. For example, a larger proportional gain can be used during startup to accelerate response, while the proportional gain can be reduced and the integral action increased as the system approaches the setpoint to eliminate residual error.

[0093] Specifically, in the proportional terminator, the deviation signal of the control system is reflected proportionally in a timely manner. Once a deviation occurs, the controller immediately generates a control action to reduce the deviation. When the deviation is 0, the control action is also 0. In the integral term, the error is memorized, mainly used to eliminate steady-state error and improve the system's error tolerance. In the derivative term, the trend of the deviation signal is reflected, and an effective early correction signal is introduced into the system before the deviation signal value becomes too large, thereby accelerating the system's response speed and reducing settling time. The PID calculation formula can be expressed as follows:

[0094]

[0095] Where u(t) is the controller output, which is the final adjusted value of the system;

[0096] e(t) is the current system error, which is usually the difference between the set value and the actual value;

[0097] Δt is the sampling time interval, representing the time step for each calculation of the control quantity;

[0098] K p It is the proportional coefficient, which determines the degree of influence of the current error on the controller output;

[0099] K i It is the integral coefficient, which determines the impact of historical error accumulation on the controller output;

[0100] K d These are the differential coefficients, which determine the impact of the error rate of change on the controller output;

[0101] This represents the cumulative error from time 0 to the current time t (discrete integral).

[0102] Represents the current rate of change of the error (the differential in discrete form).

[0103] The controller can support three modes for driving the electronic expansion valve, driving the electronic expansion valve to the corresponding number of steps.

[0104] The controller is compatible with various refrigerants and features adaptive control, allowing it to manage different refrigerant types. It provides corresponding fluid control algorithms for different refrigerants, converting the current pressure into the corresponding saturation temperature using the refrigerant's pressure-enthalpy diagram. Based on the collected temperature and pressure signals, it calculates superheat and uses a PID algorithm to calculate and control the expansion valve opening, adjusting the refrigerant flow rate to maximize system efficiency. Furthermore, it features a segmented superheat control algorithm, allowing multiple target superheat levels to be set for different ambient temperature ranges. This effectively improves the overall cooling / heating efficiency of the system in scenarios with large ambient temperature variations. It also includes high and low superheat alarm algorithms, triggering an alarm when the system superheat remains below the alarm threshold for an extended period.

[0105] The controller provides multiple control modes based on the different analog quantities collected, such as pressure control, simultaneous temperature and pressure control, and constant temperature balance control. It can also provide liquid spray control and air jet control modes depending on the system pipeline, adapting to various working conditions.

[0106] The controller's information interaction can be primarily achieved through the display module. For example, it can display the information needed by the user through an LCD screen or digital tube. Furthermore, in terms of information interaction, the circuit board has a digital tube button driver module for information display, allowing users to configure the controller's system parameters or query collected information via buttons. For instance, a classic human-machine interaction method combining digital tubes and mechanical buttons can be used, making the parameters more intuitive and easier to operate.

[0107] The controller can communicate with other peripheral devices (such as programmable logic controllers, PLCs, etc.) to exchange information. It can integrate various communication modules, including RS485, CAN, Ethernet, 4G, Bluetooth, and WiFi, to meet the needs of most application scenarios. Specifically, the controller supports multiple control protocols such as Modbus RTU (Modbus Remote Terminal Unit Protocol) and Modbus TCP / IP (Modbus Transmission Control Protocol / Internet Protocol), and supports multiple connection methods such as RS485, CAN, Ethernet, and 4G, allowing for convenient and quick switching. It also enables real-time monitoring of expansion valve steps, system evaporation pressure, intake temperature, downstream temperature, and system parameters on various terminals.

[0108] In summary, this embodiment features a controller with multiple control schemes, including temperature, pressure, and communication control, which can be automatically switched with a single button. Furthermore, it can automatically switch to other acquired signals to continue control after a certain control signal is disconnected. The controller can provide corresponding fluid control algorithms for different refrigerants and uses a PID algorithm to calculate and control the opening of the expansion valve, adjusting the refrigerant flow rate in the system to maximize system efficiency. The controller can provide two PID control algorithms, ensuring good control performance under different operating conditions. The controller supports multiple control protocols and connection methods, allowing for convenient and quick switching and real-time monitoring of multiple parameters on various terminals. Multivariable collaborative control considers the inherent relationships between various controlled objects, aiming to find the globally optimal solution. The segmented superheat control algorithm can effectively improve the overall cooling / heating efficiency of the system in scenarios with large ambient temperature variations.

[0109] The embodiments described above have been illustrated with reference to specific examples. However, this disclosure is not limited to these specific examples. Design modifications appropriate to those skilled in the art, provided the features of this disclosure are present in these specific examples, are also included within the scope of this disclosure. The elements, their configurations, conditions, shapes, etc., in the above-described specific examples are not limited to the illustrated elements and can be appropriately modified. The combination of the elements in the above-described specific examples can be appropriately changed as long as it does not create a technical contradiction.

Claims

1. An electronic expansion valve controller with a fluid control algorithm, characterized in that, include: The module comprises a signal acquisition module, a control processing module, and an output driver module; among which: The signal acquisition module includes a sensor interface, which includes at least one of an intake temperature interface, a low-pressure interface, and an exhaust temperature interface, for acquiring corresponding temperature and pressure signals and transmitting the acquired signals to the control processing module. The control processing module is connected to the signal acquisition module and is used to generate a target control signal by calling the proportional-integral-derivative PID control algorithm based on the temperature signal and pressure signal acquired by the signal acquisition module and the target control parameters corresponding to different refrigerants and control modes. The output drive module is signal-connected to the control processing module and is used to receive the target control signal output by the control processing module and convert the target control signal into a drive signal for driving the electronic expansion valve.

2. The electronic expansion valve controller with fluid control algorithm according to claim 1, characterized in that, The signal acquisition module also includes analog signal channels that correspond one-to-one with the sensor interfaces, used to transmit the output signals of the corresponding sensors; The analog signal channel includes a signal filtering unit and an anti-interference unit; The signal filtering unit includes at least one low-pass filter; The anti-interference unit includes an isolation power supply, a transient voltage suppression TVS diode, and / or a common-mode inductor.

3. The electronic expansion valve controller with fluid control algorithm according to claim 2, characterized in that, The sensor interface adopts a hot-swappable connection structure, including a multi-pin socket with flexible contacts and a corresponding plug; The signal filtering unit and the anti-interference unit are integrated in the same signal conditioning circuit board, which is connected to the sensor interface via a plug-in method.

4. The electronic expansion valve controller with fluid control algorithm according to claim 1, characterized in that, The signal acquisition module also includes an identification control unit, which is used to detect the identification parameters of the sensor when the sensor is connected, convert the identification parameters into a corresponding sensor type identifier, and output the sensor type identifier to the control processing module; After receiving the sensor type identifier, the control processing module calls the signal processing path that matches the sensor to obtain the temperature signal and pressure signal.

5. The electronic expansion valve controller with fluid control algorithm according to claim 1, characterized in that, The signal acquisition module also includes an expansion interface unit for connecting to external analog-to-digital converters, frequency-to-voltage converters, and / or serial protocol adapters to access sensors of different standards.

6. The electronic expansion valve controller with fluid control algorithm according to claim 1, characterized in that, The output drive module includes two electronic expansion valve control channels for connecting to two electronic expansion valves respectively. The electronic expansion valve control channel includes a feedback detection unit and a drive signal switching unit; The feedback detection unit is used to detect the voltage or current feedback value corresponding to the target control signal; The drive signal switching unit is at least one of a DIP switch, a jumper structure, or an automatic switching mechanism controlled by the control processing module.

7. The electronic expansion valve controller with fluid control algorithm according to claim 1, characterized in that, The control processing module includes a control mode register unit and a mode calling unit; The control mode register unit is used to register parameter groups of preset multiple control modes, including at least one of pressure control mode, temperature and pressure combined control mode, constant temperature balance control mode, liquid injection control mode and jet injection control mode. The mode calling unit is used to call the parameter group of the corresponding control mode according to the analog quantity type and system pipeline unit type obtained by the signal acquisition module.

8. The electronic expansion valve controller with fluid control algorithm according to claim 1, characterized in that, The controller also includes a display interaction module, comprising a number display unit and an input unit; The display unit includes a digital tube and / or a liquid crystal display; The input unit includes buttons, knobs, and / or dials.

9. The electronic expansion valve controller with fluid control algorithm according to claim 1, characterized in that, The controller also includes a communication module for communicating with external devices, including at least one of an RS485 communication unit, a controller area network (CAN) communication unit, an Ethernet communication unit, and a 4G communication unit.

10. The electronic expansion valve controller with fluid control algorithm according to claim 1, characterized in that, The controller includes a controller housing and a control board disposed inside the housing; The controller housing is made of fire-resistant material and supports rail mounting. The front panel of the controller housing is made of acrylic material, and the exterior of the housing is equipped with a heat dissipation structure. The control board is powered by an isolated power supply.

Images