A frequency converter cabinet for refrigeration room with electromagnetic interference protection

Abstract

This utility model discloses an electromagnetic interference-resistant inverter cabinet for a chiller room, comprising a cabinet, an electricity meter, an inverter, a communication module, a measurement module, an input module, and a display module. The inverter, communication module, and measurement module are housed inside the cabinet, while the electricity meter, input module, and display module are located on the cabinet door. The communication module is located at the output of the inverter, enabling communication between the inverter and the PLC controller of the water pump. The communication module includes an RS485 filter, an RS485 repeater amplifier, RS485 terminals, and an external RS485 communication terminal. The RS485 filter is connected to the inverter output via the RS485 terminals and also to the RS485 repeater amplifier. The RS485 repeater amplifier is connected to the PLC controller of the water pump via the external RS485 communication terminal. This utility model reduces signal interference and lowers signal transmission delay.

Description

Technical Field

[0001] This utility model belongs to the field of electrical control cabinet technology, and specifically relates to an anti-electromagnetic interference frequency converter cabinet for refrigeration rooms. Background Technology

[0002] Energy efficiency standards for high-efficiency data centers are typically measured by Coefficient of Performance (COP), which necessitates the use of frequency converters. Currently, high-efficiency data centers usually improve their COP values ​​through energy-saving measures such as variable frequency drives for water pumps and fans, generally keeping the COP above 5.0. With technological advancements, controllers now typically manage frequency converters via communication. Frequency converters consist of rectifier and inverter units. The rectification and inversion processes generate significant interference signals, which also lead to substantial interference during communication, especially with high-power motors. This abundant interference causes signal transmission delays, potentially rendering the system uncontrollable and causing system crashes. Existing technologies typically address interference issues only after they have emerged.

[0003] The information disclosed in this background section is intended only to enhance the understanding of the overall background of this utility model and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0004] The purpose of this utility model is to provide an electromagnetic interference-resistant frequency converter cabinet for refrigeration rooms, thereby overcoming the defects in the prior art.

[0005] To achieve the above objectives, this utility model provides an electromagnetic interference-resistant frequency converter cabinet for a chiller room, comprising a cabinet, an electricity meter, a frequency converter, a communication module, a measurement module, an input module, and a display module. The frequency converter, communication module, and measurement module are housed inside the cabinet, while the electricity meter, input module, and display module are mounted on the cabinet door. The power supply is connected to the frequency converter via a power circuit. The measurement module is located on the power circuit. A communication module is located at the output of the frequency converter. The frequency converter and the PLC controller of the water pump are connected via the communication module. The electricity meter is connected to the measurement module via a cable, and the input module is connected to the frequency converter via a circuit. The input terminal of the inverter is connected, and the display module is connected to the inverter via a circuit. The communication module includes an RS485 filter, an RS485 repeater amplifier, an RS485 terminal block, and an RS485 external communication terminal block. The RS485 filter is connected to the output terminal of the inverter via the RS485 terminal block, and the RS485 repeater amplifier is connected to the PLC controller of the water pump via the RS485 external communication terminal block. The RS485 filter filters out interference signals, and the RS485 repeater amplifier amplifies the filtered signals.

[0006] Preferably, in the technical solution, the frequency converter includes an input terminal interface DI1-6, output terminal interfaces A-, B+, R02B-C, R03A-C, and a power interface. The power supply is connected to the power interface of the frequency converter through a power circuit, and the frequency converter is connected to the RS485 terminal block through the output terminal interfaces A- and B+.

[0007] Preferably, in the technical solution, the measurement module is a current transformer, which is installed on the power supply circuit and connected to the electricity meter via a cable. The current transformer measures the inverter's operating voltage, current, power, and power consumption, and displays the measured values ​​on the electricity meter.

[0008] Preferably, in the technical solution, the input module includes a water pump operating mode knob, a manual start button, a manual stop button, a manual operation circuit, and an automatic control signal circuit; the water pump operating mode knob is connected to the input terminal interface DI4 via a line, and the water pump operating mode knob switches between manual mode and automatic mode; the manual operation circuit is connected to the input terminal interface DI1, and the manual operation circuit is provided with a manual start button and a manual stop button; the automatic control signal circuit is connected to the input terminal interface DI3.

[0009] Preferably, in the technical solution, the display module includes a three-phase power indicator, a frequency converter fault indicator, an automatic mode running indicator, and an automatic mode stop indicator. The three-phase power indicator is connected to the power circuit, the frequency converter fault indicator is connected to the output interface R03A, and the automatic mode running indicator and the automatic mode stop indicator are respectively connected to the output interface R02B.

[0010] Compared with the prior art, the present invention has the following beneficial effects: By filtering the signal output from the inverter, interference signals are removed, and then the filtered signal is amplified, signal interference is reduced, signal transmission delay is lowered, and control accuracy is improved. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the cabinet door structure of the electromagnetic interference-resistant inverter cabinet for the refrigeration room according to this utility model; Figure 2 This is a schematic diagram of the internal structure of the electromagnetic interference-resistant frequency converter cabinet for the refrigeration room of this utility model; Figure 3 This is the electrical diagram of the electromagnetic interference-resistant frequency converter cabinet for the refrigeration room of this utility model; Figure 4 This is the circuit diagram of the frequency converter of this utility model; Figure 5 This is the circuit diagram of the communication module of this utility model. Detailed Implementation

[0012] The specific embodiments of this utility model are described in detail below, but it should be understood that the protection scope of this utility model is not limited to the specific embodiments.

[0013] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0014] like Figure 1-2 As shown, a variable frequency drive (VFD) cabinet for refrigeration room with electromagnetic interference protection includes a cabinet 1, an electric meter 2, a VFD 3, a communication module 4, a measurement module 5, an input module 6, and a display module 7. The VFD 3, communication module 4, and measurement module 5 are installed inside the cabinet 1, and the electric meter 2, input module 6, and display module 7 are installed on the cabinet door of the cabinet 1. The power supply is connected to the VFD 3 through a power circuit 8, the measurement module 5 is installed on the power circuit 8, the output terminal of the VFD 3 is equipped with the communication module 4, the VFD 3 is connected to the PLC controller of the water pump 9 through the communication module 4, the electric meter 2 is connected to the measurement module 5 through a cable, the input module 6 is connected to the input terminal of the VFD 3 through a circuit, and the display module 7 is connected to the VFD 3 through a circuit. like Figure 3 As shown, the frequency converter 3 includes input terminal interface DI1-6, output terminal interfaces A-, B+, R02B-C, R03A-C, and a power interface. The power supply is connected to the power interface of the frequency converter 3 through the power circuit 8. like Figure 5 As shown, the communication module 4 includes an RS485 filter 40, an RS485 repeater amplifier 41, an RS485 terminal block 42, and an RS485 external communication terminal block 43. The RS485 filter 40 is connected to the output interfaces A- and B+ of the frequency converter 3 through the RS485 terminal block 42. The RS485 filter 40 is connected to the RS485 repeater amplifier 41. The RS485 repeater amplifier 41 is connected to the PLC controller of the water pump 9 through the RS485 external communication terminal block 43. The RS485 filter 40 filters interference signals, and the RS485 repeater amplifier 41 amplifies the filtered signals.

[0015] The measurement module 5 is a current transformer, which is installed on the power supply circuit 8. The current transformer is connected to the meter 2 via a cable. The current transformer measures the operating voltage, current, power and power consumption of the frequency converter 3 and displays the measured values ​​in the meter 1.

[0016] like Figure 1 , Figure 3-4As shown, the input module 6 includes a water pump operating mode knob 60, a manual start button 61, a manual stop button 62, a manual operation circuit 63, and an automatic control signal circuit 64. The water pump operating mode knob 60 is connected to the input interface DI4 via a line. When the water pump operating mode knob 60 is in the SA1-1 position, it is in manual mode; when the water pump operating mode knob 60 is in the SA1-0 position, it is in stop mode; and when the water pump operating mode knob 60 is in the SA1-2 position, it is in automatic mode. The manual operation circuit 63 is connected to the input interface DI1, and the manual operation circuit 63 is equipped with a manual start button 61 (PB1) and a manual stop button 62 (PB2). The automatic control signal circuit 64 is connected to the input interface DI3.

[0017] like Figure 1 , Figure 3-4 As shown, the display module 7 includes a three-phase power indicator 70, a frequency converter fault indicator 71, an automatic mode operation indicator 72, and an automatic mode stop indicator 73. The three-phase power indicator 70 is connected to the power circuit 8 and displays the status of the A, B, and C phase power supplies. The frequency converter fault indicator 71 is connected to the output interface R03A and displays yellow. The automatic mode operation indicator 72 and the automatic mode stop indicator 73 are connected to the output interface R02B respectively and display green and red respectively.

[0018] During operation, rotating the water pump operating mode knob 60 to automatic mode activates the frequency converter 3, which outputs the required frequency. The frequency signal is filtered for interference by an RS485 filter 40, amplified by an RS485 repeater amplifier 41, and then sent to the PLC controller of water pump 9 to adjust it to the appropriate frequency. This reduces signal interference, lowers signal transmission delay, and improves control accuracy. When manual operation is required, rotate the water pump operating mode knob 60 to manual mode, press the manual start button 61 to start or press the manual stop button 62 to stop, manually adjust the frequency input to the frequency converter 3, and then the frequency converter 3 sends a signal through the output module 4.

[0019] The cabinet 1 is also equipped with ventilation openings and fans to cool the inside of the cabinet 1.

[0020] The foregoing description of specific exemplary embodiments of the present invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the present invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the present invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the present invention, as well as various different choices and variations. The scope of the present invention is intended to be defined by the claims and their equivalents.

Claims

1. A frequency converter cabinet for refrigeration rooms that resists electromagnetic interference, characterized in that: The system includes a cabinet, an electricity meter, a frequency converter, a communication module, a measurement module, an input module, and a display module. The frequency converter, communication module, and measurement module are housed inside the cabinet. The electricity meter, input module, and display module are mounted on the cabinet door. A power supply is connected to the frequency converter via a power circuit. The measurement module is located on the power circuit. The communication module is located at the output of the frequency converter. The frequency converter and the PLC controller of the water pump are connected via the communication module. The electricity meter is connected to the measurement module via a cable. The input module is connected to the input of the frequency converter via a circuit. The display module is connected to the frequency converter via a circuit. The communication module includes an RS485 filter, an RS485 repeater amplifier, RS485 terminals, and an external RS485 communication terminal. The RS485 filter is connected to the output of the frequency converter via the RS485 terminals. The RS485 filter is connected to the RS485 repeater amplifier. The RS485 repeater amplifier is connected to the PLC controller of the water pump via the external RS485 communication terminal.

2. The anti-electromagnetic interference frequency converter cabinet for refrigeration rooms according to claim 1, characterized in that: The frequency converter includes input interface DI1-6, output interfaces A-, B+, R02B-C, R03A-C, and a power interface. The power supply is connected to the power interface of the frequency converter through the power circuit. The frequency converter is connected to the RS485 terminal block through the output interfaces A- and B+.

3. The anti-electromagnetic interference frequency converter cabinet for refrigeration rooms according to claim 2, characterized in that: The measurement module is a current transformer, which is installed on the power supply circuit and connected to the meter via a cable.

4. The anti-electromagnetic interference frequency converter cabinet for refrigeration rooms according to claim 2, characterized in that: The input module includes a water pump operating mode knob, a manual start button, a manual stop button, a manual operation circuit, and an automatic control signal circuit. The water pump operating mode knob is connected to the input interface DI4 via a line, and the water pump operating mode knob switches between manual and automatic modes. The manual operation circuit is connected to the input interface DI1, and the manual operation circuit is equipped with a manual start button and a manual stop button. The automatic control signal circuit is connected to the input interface DI3.

5. The anti-electromagnetic interference frequency converter cabinet for refrigeration rooms according to claim 4, characterized in that: The display module includes a three-phase power indicator, an inverter fault indicator, an automatic mode running indicator, and an automatic mode stop indicator. The three-phase power indicator is connected to the power circuit, the inverter fault indicator is connected to the output interface R03A, and the automatic mode running indicator and the automatic mode stop indicator are connected to the output interface R02B respectively.

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