Screw water-cooling water chilling unit

Abstract

The utility model provides a screw water-cooling water chilling unit which comprises a screw compressor, a screw water-cooling water chilling unit body and a screw water-cooling water chilling unit body. The main control module is at least used for driving the screw compressor to operate; one or more expansion modules, wherein the expansion modules are arranged independently from the main control module; the main control module and the expansion module are respectively in communication connection with the differential communication bus through the communication driving module; the communication driving module is used for generating a differential signal and sending the differential signal to the differential communication bus, and is used for receiving the differential signal from the differential communication bus. According to the application, the modular design, the differential communication bus and the communication driving module are adopted, the cooperative work between the main control module and the expansion module is ensured, the expandability and the communication stability are better, and the communication cost is remarkably reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of air conditioning, in particular to a screw water-cooled chiller. Background Art

[0002] A screw water-cooled chiller primarily consists of a screw compressor, condenser, throttling element, and evaporator. It follows the refrigeration cycle, with the screw compressor as the key component. It compresses low-temperature, low-pressure refrigerant into high-temperature, high-pressure refrigerant. Heat is then dissipated through the condenser, reduced by the expansion valve, and finally absorbed by the evaporator, completing the refrigeration cycle. Screw compressors typically compress gas through the rotation of two screws.

[0003] Controlling a screw water-cooled chiller through a PLC (Programmable Logic Controller) is an intelligent approach that allows for more precise and flexible control of the refrigeration system. The PLC's input module is configured to receive information from sensors, such as temperature sensors and pressure sensors, and the PLC's output module is configured to control actuators, such as the screw compressor, cooling water pump, condenser fan, and throttling element 14. This allows the system to collect data from various sensors, monitor the system's operating status, and control the operation of various actuators, such as adjusting the operating frequency of the screw compressor, controlling the start and stop of the cooling water pump, and adjusting the speed of the condenser fan to meet the current load demand.

[0004] Because PLCs from different manufacturers use different communication protocols and standards, connecting a PLC to another device (such as a sensor, actuator, or other PLC) using different communication protocols requires a communication conversion module to perform protocol conversion. This requires each PLC to be equipped with a separate communication conversion module for signal transmission, resulting in a complex control system, high equipment purchase price, and high subsequent maintenance costs. Utility Model Content

[0005] For the existing screw water-cooled chillers, PLC is used as the control core. Since PLCs from different manufacturers use different communication protocols and standards, each PLC needs to be equipped with a separate communication conversion module for signal transmission, resulting in a complex control system and high cost. This application designs and provides a screw water-cooled chiller.

[0006] A screw water-cooled chiller comprises: a screw compressor for compressing refrigerant; and a main control module for at least driving the operation of the screw compressor.

[0007] In one or more embodiments of the present application, the screw water-cooled chiller also includes: one or more extension modules, which are independently arranged from the main control module; a differential communication bus, and the main control module and the extension module are respectively connected to the differential communication bus through a communication driver module; the communication driver module is used to generate a differential signal and send the differential signal to the differential communication bus, and is used to receive a differential signal from the differential communication bus.

[0008] In one or more embodiments of the present application, the differential communication bus is a HomeBUS communication bus; and the communication driver module includes an HBS-compatible transceiver chip.

[0009] In one or more embodiments of the present application, the communication driving module further includes: a signal sending circuit, which is arranged between the signal sending end and the HBS-compatible transceiver chip; the signal sending circuit includes: a first transistor, whose base is electrically connected to the signal sending end and the emitter is grounded; a second transistor, whose base is electrically connected to the clock signal end and the emitter is grounded; and a third transistor, whose base is electrically connected to the collector of the first transistor and the collector of the second transistor, the emitter is grounded, and the collector is electrically connected to the input pin of the HBS-compatible transceiver chip; the base of the third transistor is connected to the power supply via a first resistor, and the collector of the third transistor is connected to the power supply via a second resistor; a first capacitor is arranged between the emitter and the base of the third transistor.

[0010] In one or more embodiments of the present application, the communication driving module further includes: a transmitting side coupling circuit, one end of which is electrically connected to the transmitting pin of the HBS compatible transceiver chip, and the other end of which is electrically connected to the HomeBUS communication bus.

[0011] In one or more embodiments of the present application, the communication driving module further includes: a receiving-side coupling circuit, one end of which is electrically connected to the HomeBUS communication bus and the other end of which is electrically connected to a receiving pin of the HBS-compatible transceiver chip.

[0012] In one or more embodiments of the present application, the communication driving module also includes: a signal receiving circuit, which is arranged between the HBS-compatible transceiver chip and the signal receiving end; the signal receiving circuit includes: a common anode diode, the anode of the common anode diode is electrically connected to the output pin of the HBS-compatible transceiver chip, and one cathode is electrically connected to the power supply via a third resistor; a fourth transistor, the base of the fourth transistor is electrically connected to the other cathode of the common anode diode, the emitter is grounded, and the collector is electrically connected to the power supply via a fourth resistor; and a fifth transistor, the base of the fifth transistor is electrically connected to the base of the fourth transistor, the emitter is grounded, and the collector is connected to the power supply via a fifth resistor.

[0013] In one or more embodiments of the present application, the signal receiving circuit further includes: a sixth resistor, a first end of the sixth resistor being electrically connected to a power supply; a first light-emitting diode, an anode of the first light-emitting diode being electrically connected to the second end of the sixth resistor, and a cathode thereof being electrically connected to the signal receiving end; and a second capacitor, the second capacitor being arranged between the signal receiving end and the ground end.

[0014] In one or more embodiments of the present application, the differential communication bus includes: a first differential signal end and a second differential signal end; the communication driving module also includes: a first protection circuit, which is arranged between the sending side coupling circuit, the receiving side coupling circuit and the differential communication bus; the first protection circuit includes: a fuse, one end of the fuse is electrically connected to the first differential signal end; a first diode, the anode of the first diode is electrically connected to the other end of the fuse; a first varistor, the first end of the first varistor is connected to the cathode of the first diode, the second end of the first varistor is electrically connected to the second differential signal end, one end is electrically connected to the sending side coupling circuit, and the other end is electrically connected to the receiving side coupling circuit; a second varistor, the first end of the second varistor is electrically connected to the other end of the fuse; a second diode, the cathode of the second diode is electrically connected to the second end of the second varistor, the anode of the second diode is electrically connected to the second differential signal end, one end is electrically connected to the sending side coupling circuit, and the other end is electrically connected to the receiving side coupling circuit.

[0015] In one or more embodiments of the present application, the communication driving module also includes: a second protection circuit, which is arranged between the sending side coupling circuit and the ground end; it includes: a first Zener diode, whose anode is electrically connected to the sending side coupling circuit; a second Zener diode, whose cathode is electrically connected to the cathode of the first Zener diode, and the anode is grounded; a third Zener diode, whose anode is electrically connected to the sending side coupling circuit; and a fourth Zener diode, whose cathode is electrically connected to the cathode of the first Zener diode, and the anode is grounded.

[0016] In one or more embodiments of the present application, the communication driver module further includes: a HomeBUS driver circuit, comprising: a first driver transistor, a base of which is electrically connected to a first driver pin of the HBS-compatible transceiver chip, an emitter is grounded, and a collector is electrically connected to the transmission pin and the transmission-side coupling circuit; and a second driver transistor, a base of which is electrically connected to a second driver pin of the HBS-compatible transceiver chip, an emitter is grounded, and a collector is electrically connected to the transmission pin and the transmission-side coupling circuit.

[0017] This application adopts a modular design, which improves the system flexibility of the screw water-cooled chiller and is easy to upgrade and maintain. A differential communication bus is introduced in the screw water-cooled chiller. The main control module and the expansion module communicate through the differential communication bus, which can provide reliable data transmission, reduce interference, and improve communication stability. The communication driver module realizes the sending and receiving of differential signals, which helps to achieve efficient data exchange and ensure the coordinated operation between the main control module and the expansion module. This application has better scalability and communication stability, and significantly reduces communication costs.

[0018] After reading the specific embodiments of the present invention in conjunction with the accompanying drawings, other features and advantages of the present invention will become more clear. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0020] Figure 1 A schematic diagram of the structure of a screw water-cooled chiller provided in one or more embodiments of the present application;

[0021] Figure 2 A schematic block diagram of the structure of a screw water-cooled chiller provided in one or more embodiments of the present application;

[0022] Figure 3 A schematic block diagram of the structure of a communication drive module in a screw water-cooled chiller provided in one or more embodiments of the present application;

[0023] Figure 4 A circuit diagram of a communication drive module in a screw water-cooled chiller provided in one or more embodiments of the present application;

[0024] Figure 5A circuit diagram of a communication drive module in a screw water-cooled chiller provided in one or more embodiments of the present application;

[0025] Figure 6 for Figure 5 A partial enlarged view of point A in the middle;

[0026] Figure 7 for Figure 5 A partial enlarged view of point B in the middle;

[0027] Figure 8 for Figure 5 A partial enlarged view of point C in the middle;

[0028] Figure 9 for Figure 5 A partial enlarged view of point D in the middle;

[0029] Figure 10 for Figure 5 A partial enlarged view of point E in the middle;

[0030] Figure 11 for Figure 5 A partial enlarged view of point F in the middle;

[0031] Figure 12 for Figure 5 A partial enlarged view of point G in the middle;

[0032] Figure 13 for Figure 5 A partial enlarged view of the H in the middle;

[0033] Figure 14 A communication timing diagram of a communication drive module in a screw water-cooled chiller provided by one or more embodiments of the present application;

[0034] In the figure: 10, compressor; 11, condenser; 12, cooling tower; 13, cooling water pump; 14, throttling element; 15, evaporator; 16, chilled water pump; 17, terminal; 20, main control module; 21, communication driver module; 22, differential communication bus; 23, extension module; 201, HBS-compatible transceiver chip; 202, signal sending circuit; 203, signal receiving circuit; 204, receiving side coupling circuit; 205, sending side coupling circuit. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0036] In the description of this application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0037] The terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, features specified as "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0038] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0039] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes the first feature being directly below and obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0040] The disclosure below provides many different embodiments or examples for realizing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. In addition, the present invention may repeat reference numbers and / or reference letters in different examples. Such repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides examples of various specific processes and materials, but a person of ordinary skill in the art will recognize the application of other processes and / or the use of other materials.

[0041] For the existing screw water-cooled chillers, PLC (Programmable Logic Controller) is used as the control core. Since PLCs from different manufacturers use different communication protocols and standards, each PLC needs to be equipped with a separate communication module for signal transmission, resulting in complex control systems and high costs. Figure 1 As shown, the present application designs and provides a screw water-cooled chiller.

[0042] Water-cooled chillers are specialized refrigeration equipment used primarily in large commercial buildings, industrial process cooling, and other applications requiring efficient cooling. Water-cooled chillers utilize a water condensation process, where water absorbs and dissipates heat in the condenser 11. This process offers higher efficiency in high-temperature environments compared to traditional air condensation.

[0043] A refrigeration cycle is integrated into a water-cooled chiller. This cycle is primarily implemented by a refrigerant circuit, which utilizes a compressor 10, a condenser 11, a throttling element 14, and an evaporator 15. The refrigeration cycle involves a series of processes, including compression, condensation, expansion, and evaporation.

[0044] In principle, low-temperature, low-pressure refrigerant enters compressor 10, which compresses it into high-temperature, high-pressure refrigerant gas and discharges the compressed refrigerant gas. The discharged refrigerant gas flows into condenser 11. Condenser 11 condenses the compressed refrigerant into a liquid phase, releasing heat into the surrounding environment through the condensation process.

[0045] In a water-cooled chiller, a water-cooled condenser 11 replaces a traditional air-cooled condenser. Water is used as a medium to cool the high-temperature, high-pressure refrigerant, converting it into a high-pressure liquid. A cooling water pump 13 circulates the cooling water between the condenser 11 and a cooling tower 12, which lowers the temperature of the cooling water in the water-cooled condenser 11. For example, the cooling tower 12 exposes the hot water after heat exchange to the air, utilizing natural convection to lower the water temperature.

[0046] The throttle element 14 expands the high-temperature and high-pressure liquid-phase refrigerant condensed in the condenser 11 into a low-pressure liquid-phase refrigerant.

[0047] The evaporator 15 evaporates the refrigerant expanded in the throttling element 14 and returns the low-temperature, low-pressure refrigerant gas to the compressor 10. The evaporator 15 can achieve a cooling effect by utilizing the latent heat of evaporation of the refrigerant to exchange heat with the material to be cooled. For example, the evaporator 15 can be used to change the temperature of the chilled water, which can then be further used to reduce the temperature within the room or system at a terminal 17 (e.g., a fan coil unit). The chilled water can be driven by a chilled water pump 16.

[0048] In one or more embodiments of the present application, the compressor 10 is a screw compressor 10. The screw compressor 10 compresses the gas through the movement of two screws (or helical gears). Typically, one screw is fixed and the other screw rotates around it, forming a closed chamber for the gas between the two screws. As the screws rotate, the gas is gradually compressed between the two screws and eventually discharged to the high-pressure end. By adjusting the speed of the screw operation, the actual system requirements of the screw water-cooled chiller can be more effectively matched, thereby achieving energy savings.

[0049] The screw water-cooled chiller is equipped with a main control module 20, which is used to at least drive the operation of the screw compressor 10. In one or more embodiments of the present application, the main control module 20 can also be used to drive the operation of the cooling water pump 13 and the chilled water pump 16. The operation of the screw compressor 10 includes starting, stopping, and adjusting the operating speed of the screw compressor 10; the operation of the cooling water pump 13 and the chilled water pump 16 includes starting, stopping, and adjusting the operating speed of the cooling water pump 13 and the chilled water pump 16. The main control module 20 is pre-installed with a control algorithm to perform the above functions. The control algorithm is well known in the prior art and is not protected by the present invention. It will not be further described here.

[0050] In one or more embodiments of the present application, the main control module 20 adopts a microcontroller (MCU), which is a single-chip microprocessor that integrates functions such as a central processing unit (CPU), memory (RAM, Flash, etc.), input / output interface (I / O), timer (Timer) and communication interface (UART, SPI, I2C, etc.).

[0051] like Figure 2As shown, in one or more embodiments of the present application, the screw water-cooled chiller further includes one or more expansion modules 23, which are independently configured from the main control module 20. In addition to actuators such as the screw compressor 10, cooling water pump 13, and chilled water pump 16, the expansion modules 23 may also be sensor modules, such as temperature sensors for measuring various temperature parameters, including but not limited to temperature sensors for monitoring the cooling water inlet and outlet temperatures, the temperature of the condenser 11, and the temperature of the evaporator 15. They may also include pressure sensors for measuring system pressure changes, flow sensors for monitoring the cooling water flow rate, and water level sensors for monitoring the water level. In addition to sensor modules, the expansion modules 23 may also be early warning modules for generating alarms when abnormalities or faults are detected. The expansion modules 23 may also be human-computer interaction modules, such as display screens or human-machine interfaces, providing a user with a visual interface displaying the system's operating status, parameters, and alarm information. These expansion modules 23 are independently configured from the main control module 20 and communicate with it to enable comprehensive monitoring of the screw water-cooled chiller. Each expansion module 23 may be integrated with a microcontroller.

[0052] In one or more embodiments of the present application, the screw water-cooled chiller is further provided with a differential communication bus 22. The main control module 20 and the expansion module 23 are respectively connected to the differential communication bus 22 via a communication driver module 21. The communication driver module 21 is configured to generate differential signals and transmit the differential signals to the differential communication bus 22, and to receive differential signals from the differential communication bus 22.

[0053] Specifically, the main control module 20 and multiple expansion modules 23 (taking multiple expansion modules 23 as an example) communicate through the communication driver module 21 and the differential communication bus 22. The main control module 20 and the multiple expansion modules 23 are connected together through the differential communication bus 22. The main control module 20 and the expansion module 23 are both provided with a communication driver module 21, thereby realizing data transmission and reception. When the main control module 20 sends data, the communication driver module 21 connected to the main control module 20 transmits the data to be sent to the differential communication bus 22, and the communication driver module 21 connected to the expansion module 23 returns the data on the differential communication bus 22 to the expansion module 23. When the expansion module 23 sends data, the communication driver module 21 connected to the expansion module 23 transmits the data to be sent to the differential communication bus 22, and the communication driver module 21 connected to the main control module 20 returns the data on the differential communication bus 22 to the main control module 20, thereby achieving stable data transmission. Compared with the PLC communication module, the cost is significantly reduced.

[0054] The differential communication bus 22 communicates data by transmitting differential signals. It uses twisted, paired wires as the physical carrier, with signal differences (e.g., voltage differences) between the wires carrying the communication data. This differential communication bus 22 can cancel common-mode noise at the receiving end, providing improved interference immunity and ensuring signal quality over long distances. This makes it particularly suitable for screw-type water-cooled chillers used in industrial control applications, often in harsh environments.

[0055] In one or more embodiments of the present application, the differential communication bus 22 is a HomeBUS communication bus. The communication driver module 21 includes an HBS-compatible transceiver chip 201. For example, the HBS-compatible transceiver chip 201 can be the MM1192 chip produced by Mitsumi Corporation of Japan, or a similar chip produced by other companies, such as the HomeBUS TxRx chip produced by Analog Devices (ADI), such as the MAX22288. The communication driver module 21 provided with the HBS-compatible transceiver chip 201 can also be referred to as a Hilink communication circuit.

[0056] It should be noted that the HomeBUS communication bus is a home bus system developed in Japan. It uses a power carrier to transmit differential signals onto two bus lines, enabling simultaneous power supply and communication. The HomeBUS communication bus uses differential signaling to transmit data, suppressing common-mode interference and improving communication reliability. It is suitable for multi-node, long-distance communication systems for water-cooled chillers. The interface protocol of the HomeBUS communication bus is not the subject of this invention and will not be discussed here.

[0057] The following uses the chip MM1192 of Mitsumi Corporation of Japan as the HBS compatible transceiver chip 201 as an example. Figure 3 The circuit design of the communication driver module 21 provided in one or more embodiments of the present application is introduced.

[0058] In one or more embodiments of the present application, reference is made to Figure 3 、 Figure 4 、 Figure 5 and Figure 6 The communication driving module 21 includes a signal sending circuit 202 , which is arranged between the signal sending terminal TXD and the HBS compatible transceiver chip 201 .

[0059] In one or more embodiments of the present application, reference is made to Figure 4 、 Figure 5 and Figure 6The signal transmission circuit 202 includes a first transistor Q4, a second transistor Q7, and a third transistor Q6. The base of the first transistor Q4 is electrically connected to the signal transmission terminal TXD, and the emitter is grounded. The base of the second transistor Q7 is electrically connected to the clock signal terminal SCK, and the emitter is grounded. The base of the third transistor Q6 is electrically connected to the collector of the first transistor Q4 and the collector of the second transistor Q7, the emitter is grounded, and the collector is electrically connected to the input pin IN of the HBS-compatible transceiver chip 201. The base of the third transistor Q6 is connected to the power supply +5V via a first resistor R24, and the collector of the third transistor Q6 is connected to the power supply +5V via a second resistor R21. A first capacitor C11 is provided between the emitter and base of the third transistor Q6.

[0060] The signal after the logic operation of the first transistor Q4, the second transistor Q7 and the third transistor Q6 enters the input pin IN of the HBS-compatible transceiver chip 201, is converted into a differential signal by the transmitting circuit inside the MM1192 chip, and is output from the transmitting pins of the HBS-compatible transceiver chip 201, such as the Out / A and Out / B pins of the MM1192 chip.

[0061] In one or more embodiments of the present application, reference is made to Figure 3 、 Figure 4 、 Figure 5 and Figure 7 As shown, the communication driver module 21 further includes a transmitting side coupling circuit 205. One end of the transmitting side coupling circuit 205 is electrically connected to the transmitting pins Out / A and Out / B of the HBS compatible transceiver chip 201, and the other end is electrically connected to the HomeBUS communication bus.

[0062] In one or more embodiments of the present application, reference is made to Figure 4 、 Figure 5 and Figure 7 As shown, the transmitting-side coupling circuit 205 exemplarily includes a resistor R17 and a capacitor C9 connected in parallel, as well as a resistor R15 and a capacitor C7 connected in parallel. The two independent parallel resistors and capacitors together form a coupling network that can improve the signal's anti-interference performance, suppress common-mode noise, and enhance the quality of the differential signal, ensuring that the differential signal is transmitted in an efficient, stable, and reliable manner.

[0063] The signal transmission circuit 202 realizes logic and operation through the combination of the first transistor Q4, the second transistor Q7 and the third transistor Q6. The signal transmission terminal TXD is the data signal to be transmitted. An example of the data signal is as follows: Figure 14 As shown in the first row ① in the figure; the clock signal terminal SCK is the clock signal. An example of a clock signal is as follows Figure 14As shown in the second row ② in the figure. When any one of the data signal and the clock signal is at a high level, the corresponding first transistor Q4 and / or second transistor Q7 is turned on, current flows into the base of the third transistor, the third transistor Q6 is turned on, and the output is a high level; only when the data signal and the clock signal are both at a low level, the corresponding first transistor Q4 and second transistor Q7 are turned off, current cannot flow into the third transistor Q6, and the output is a low level. An example of the signal at the collector of the third transistor is shown as follows: Figure 14 This is shown in the third row ③ of the diagram. After performing a logical operation on the data and clock signals, the 100% duty signal is converted into a 50% duty signal. This means that the duty cycle of the original signal is changed from a permanently high state to one where the high and low times are equal. This is square wave encoding, which achieves a more balanced duty cycle and prevents the accumulation of DC components on the decoupling capacitors, which would otherwise degrade communication quality.

[0064] Similarly, in the reverse communication path, the differential signal on the HomeBus bus enters from the transmit pin of the HBS-compatible transceiver chip 201 (e.g., the IN1 and IN2 pins of the MM1192), is converted into a digital signal by the receiving circuit inside the chip, and is sent out from the output pin of the HBS-compatible transceiver chip 201 (e.g., the Out pin of the MM1192). For the MM1192, after the differential signal enters the MM1192 chip, the digital signal conversion is performed by comparing the difference of the differential signal with the receiving sensitivity VRS; more specifically, when the difference of the differential signal |V IN1 -V IN2 |>VRS, the output pin Out of the HBS compatible transceiver chip 201 outputs a signal of 0; when the difference of the differential signal |V IN1 -V IN2 When |<VRS, the output pin Out of the HBS compatible transceiver chip 201 outputs a signal 1. The working principle of MM1192 is not the subject of protection of the present invention and is omitted for clarity.

[0065] In one or more embodiments of the present application, reference is made to Figure 3 、 Figure 4 、 Figure 5 and Figure 8 As shown, the communication driver module 21 further includes a receiving side coupling circuit 204. One end of the receiving side coupling circuit 204 is electrically connected to the transmitting pins of the HBS compatible transceiver chip 201 (eg, IN1 and IN2 pins of MM1192), and the other end is electrically connected to the HomeBUS communication bus.

[0066] In one or more embodiments of the present application, reference is made to Figure 4 、 Figure 5 and Figure 8As shown, the receiving side coupling circuit 204 includes a resistor R10 and a capacitor C2 arranged in series, and a resistor R13 and a capacitor C5 arranged in series. The two independent resistors and capacitors arranged in series together form a coupling network, which can help adjust the input impedance of the receiving side to ensure impedance matching with the transmission line or other receiving equipment. For example, an example of a signal at the HomeBUS bus end is as follows: Figure 14 As shown in the fourth row ④ and the fifth row ⑤.

[0067] In one or more embodiments of the present application, reference is made to Figure 3 、 Figure 4 、 Figure 5 and Figure 9 As shown, the communication driving module 21 further includes a signal receiving circuit 203. The signal receiving circuit 203 is provided between the HBS compatible transceiver chip 201 and the signal receiving terminal RXD.

[0068] In one or more embodiments of the present application, reference is made to Figure 4 、 Figure 5 and Figure 9 As shown, the signal receiving circuit 203 includes a common-anode diode VD2, a fourth transistor Q2, and a fifth transistor Q1. In the signal receiving circuit, the anode of the common-anode diode VD2 is electrically connected to an output pin of the HBS-compatible transceiver chip 201 (e.g., the Out pin of the MM1192 chip), and one cathode is electrically connected to the +5V power supply via a third resistor R3. The base of the fourth transistor Q2 is electrically connected to the other cathode of the common-anode diode VD2, the emitter is grounded, and the collector is electrically connected to the +5V power supply via a fourth resistor R5. The base of the fifth transistor Q1 is electrically connected to the base of the fourth transistor Q2, the emitter is grounded, and the collector is connected to the +5V power supply via a fifth resistor R4. The signal receiving circuit 203 is used to filter out noise from the waveform of the HBS-compatible transceiver chip 201 and transmit the signal intact to the expansion module 23 or the main control module 20. An RC filter circuit consisting of a resistor R6 and a capacitor C1 is also provided between the common-anode diode VD2 and the fourth transistor Q2.

[0069] In one or more embodiments of the present application, reference is made to Figure 4 、 Figure 5 and Figure 10As shown, the signal receiving circuit 203 also includes a sixth resistor R2, a first light-emitting diode LED2, and a second capacitor C4. The first end of the sixth resistor R2 is electrically connected to the power supply +5V, the anode of the first light-emitting diode LED2 is electrically connected to the second end of the sixth resistor R2, and the cathode is electrically connected to the signal receiving terminal RXD. The second capacitor C4 is arranged between the signal receiving terminal RXD and the ground terminal. Based on the RC delay circuit, the 50% duty signal is delayed and processed by the signal receiving circuit 203 and converted into a 100% duty signal. An example of the delayed signal is shown as follows: Figure 14 The 100% duty signal can be transmitted to the MCU of the main control module 20 or the MCU of the expansion module 23, for example, through a UART interface.

[0070] In one or more embodiments of the present application, reference is made to Figure 4 、 Figure 5 and Figure 11 As shown, the differential communication bus 22 includes a first differential signal terminal HLINK-1 and a second differential signal terminal HLINK-2. The communication driver module 21 also includes a first protection circuit, which is provided between the transmitting-side coupling circuit 205, the receiving-side coupling circuit 204, and the differential communication bus 22. The first protection circuit includes a fuse F1, a first diode VD4, a first varistor Z2, a second varistor Z1, and a second diode VD3. One end of the fuse F1 is electrically connected to the first differential signal terminal HLINK-1, the anode of the first diode VD4 is electrically connected to the other end of the fuse F1, the first end of the first varistor Z2 is connected to the cathode of the first diode VD4, the second end of the first varistor Z2 is electrically connected to the second differential signal terminal HLINK-2, one path is electrically connected to the transmitting side coupling circuit 205, and the other path is electrically connected to the receiving side coupling circuit 204, the first end of the second varistor Z1 is electrically connected to the other end of the fuse F1, the cathode of the second diode VD3 is electrically connected to the second end of the second varistor Z1, the anode of the second diode VD3 is electrically connected to the second differential signal terminal HLINK-2, one path is electrically connected to the transmitting side coupling circuit 205, and the other path is electrically connected to the receiving side coupling circuit 204.

[0071] The first protection circuit is used to protect the communication circuit when a 220V voltage is mistakenly connected. When a 220V voltage is applied, the first varistor Z2 and the second varistor Z1 are activated due to overvoltage protection, causing the impedance to drop rapidly, the circuit to instantly overcurrent, and the fuse F1 to melt, disconnecting the circuit. Because the voltage on the communication circuit side is clamped by the first varistor Z2 and the second varistor Z1 at this time, overvoltage will not occur in the communication circuit. It is preferable to configure a dip switch in the first protection circuit. After the fuse F1 melts, the dip switch can be used to restore the communication circuit to normal.

[0072] In one or more embodiments of this application, see Figure 4 、 Figure 5 and Figure 12 As shown, the communication driver module 21 also includes a second protection circuit. The second protection circuit is disposed between the transmitting-side coupling circuit 205 and the ground terminal. The second protection circuit includes a first Zener diode VZ1, a second Zener diode VZ3, a third Zener diode VZ2, and a fourth Zener diode VZ4. The anode of the first Zener diode VZ1 is electrically connected to the transmitting-side coupling circuit 205, the cathode of the second Zener diode VZ3 is electrically connected to the cathode of the first Zener diode VZ1, and the anode is grounded. The anode of the third Zener diode VZ2 is electrically connected to the transmitting-side coupling circuit 205, and the cathode of the fourth Zener diode VZ4 is electrically connected to the cathode of the first Zener diode VZ1, and the anode is grounded. The second protection circuit is a negative voltage protection circuit. When negative voltage appears on the HomeBUS bus, the first Zener diode VZ1, the second Zener diode VZ3, the third Zener diode VZ2, and the fourth Zener diode VZ4 can clamp the MM1192 chip to prevent malfunction caused by the negative voltage.

[0073] In one or more embodiments of this application, see Figure 4 、 Figure 5 and Figure 13 As shown, the communication driver module 21 further includes a HomeBUS driver circuit, which includes a first driver transistor Q5 and a second driver transistor Q8. The first driver transistor Q5 has a base electrically connected to a first driver pin of the HBS-compatible transceiver chip 201 (e.g., the Out / a pin of the MM1192 chip), an emitter grounded, and a collector electrically connected to a transmit pin (e.g., the Out / A pin of the MM1192 chip) and the transmit-side coupling circuit 205. The second driver transistor Q8 has a base electrically connected to a second driver pin of the HBS-compatible transceiver chip 201 (e.g., the Out / b pin of the MM1192 chip), an emitter grounded, and a collector electrically connected to a transmit pin (e.g., the Out / B pin of the MM1192 chip) and the transmit-side coupling circuit 205.

[0074] In one or more embodiments of this application, see Figure 4 and Figure 5 As shown, for the MM1192 chip, a capacitor C6 is further provided between its C1 and C2 pins, an electrolytic capacitor E1 and a capacitor C14 are further provided on the Vcc pin, and the Coll / a, GND and Coll / b pins are grounded.

[0075] In the description of the above embodiments, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0076] The above are only specific embodiments of the present invention, but the scope of protection of the present invention is not limited to them. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this utility model should be included in the scope of protection of the present utility model. Therefore, the scope of protection of the present utility model should be based on the scope of protection of the claims.

Claims

1. Screw water-cooled chiller, including: A screw compressor, wherein the screw compressor is used to compress a refrigerant; and A main control module, the main control module is at least used to drive the operation of the screw compressor; It is characterized by further comprising: One or more expansion modules, wherein the expansion modules are independently arranged from the main control module; A differential communication bus, wherein the main control module and the expansion module are respectively connected to the differential communication bus through a communication driver module; the communication driver module is used to generate a differential signal and send the differential signal to the differential communication bus, and is used to receive a differential signal from the differential communication bus.

2. The screw water-cooled chiller according to claim 1, characterized in that: The differential communication bus is a HomeBUS communication bus; and the communication driver module includes an HBS compatible transceiver chip.

3. The screw water-cooled chiller according to claim 2, characterized in that: The communication driver module also includes: A signal transmission circuit is provided between the signal transmission end and the HBS compatible transceiver chip; the signal transmission circuit comprises: A first triode, a base of which is electrically connected to the signal sending end and an emitter is grounded; A second triode, a base of which is electrically connected to the clock signal terminal and an emitter of which is grounded; and A third triode, whose base is electrically connected to the collector of the first triode and the collector of the second triode, whose emitter is grounded, and whose collector is electrically connected to the input pin of the HBS-compatible transceiver chip; the base of the third triode is connected to the power supply via a first resistor, and the collector of the third triode is connected to the power supply via a second resistor; a first capacitor is arranged between the emitter and the base of the third triode.

4. The screw water-cooled chiller according to claim 3, characterized in that: The communication driver module also includes: A transmitting side coupling circuit, one end of which is electrically connected to a transmitting pin of the HBS compatible transceiver chip, and the other end of which is electrically connected to the HomeBUS communication bus.

5. The screw water-cooled chiller according to claim 4, characterized in that: The communication driver module also includes: A receiving-side coupling circuit, one end of which is electrically connected to the HomeBUS communication bus, and the other end of which is electrically connected to a receiving pin of the HBS-compatible transceiver chip.

6. The screw water-cooled chiller according to claim 5, characterized in that: The communication driver module also includes: A signal receiving circuit is arranged between the HBS compatible transceiver chip and the signal receiving end; the signal receiving circuit comprises: A common anode diode, wherein an anode of the common anode diode is electrically connected to an output pin of the HBS-compatible transceiver chip, and a cathode of the common anode diode is electrically connected to a power supply via a third resistor; a fourth triode, wherein the base of the fourth triode is electrically connected to the other cathode of the common anode diode, the emitter is grounded, and the collector is electrically connected to the power supply via a fourth resistor; and A fifth transistor, wherein the base of the fifth transistor is electrically connected to the base of the fourth transistor, the emitter is grounded, and the collector is connected to the power supply via a fifth resistor.

7. The screw water-cooled chiller according to claim 6, characterized in that: The signal receiving circuit also includes: a sixth resistor, wherein a first end of the sixth resistor is electrically connected to a power supply; a first light emitting diode, wherein an anode of the first light emitting diode is electrically connected to the second end of the sixth resistor, and a cathode of the first light emitting diode is electrically connected to the signal receiving end; A second capacitor is arranged between the signal receiving end and the ground end.

8. The screw water-cooled chiller according to claim 7, characterized in that: The differential communication bus comprises: a first differential signal terminal and a second differential signal terminal; The communication driver module also includes: A first protection circuit is provided between the transmitting side coupling circuit, the receiving side coupling circuit and the differential communication bus; the first protection circuit comprises: a fuse, one end of which is electrically connected to the first differential signal end; a first diode, wherein an anode of the first diode is electrically connected to the other end of the fuse; a first varistor, wherein a first end of the first varistor is connected to a cathode of the first diode, a second end of the first varistor is electrically connected to the second differential signal end, one end is electrically connected to the transmitting side coupling circuit, and another end is electrically connected to the receiving side coupling circuit; a second varistor, wherein a first end of the second varistor is electrically connected to the other end of the fuse; A second diode, a cathode of the second diode is electrically connected to the second end of the second varistor, an anode of the second diode is electrically connected to the second differential signal end, one path is electrically connected to the transmitting side coupling circuit, and the other path is electrically connected to the receiving side coupling circuit.

9. The screw water-cooled chiller according to claim 8, characterized in that: The communication driver module also includes: A second protection circuit, wherein the second protection circuit is arranged between the transmission side coupling circuit and the ground terminal; It includes: a first Zener diode, an anode of which is electrically connected to the transmission-side coupling circuit; a second Zener diode, a cathode of which is electrically connected to the cathode of the first Zener diode and an anode of which is grounded; a third Zener diode, an anode of which is electrically connected to the transmission-side coupling circuit; and The fourth Zener diode has a cathode electrically connected to the cathode of the first Zener diode and an anode grounded.

10. The screw water-cooled chiller according to claim 9, characterized in that: The communication driver module also includes: HomeBUS driving circuit, comprising: A first driving transistor, a base of which is electrically connected to a first driving pin of the HBS compatible transceiver chip, an emitter is grounded, and a collector is electrically connected to the transmitting pin and the transmitting-side coupling circuit; and The second driving transistor has a base electrically connected to the second driving pin of the HBS compatible transceiver chip, an emitter grounded, and a collector electrically connected to the sending pin and the sending side coupling circuit.

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