A detection device for a dryer in an air compressor

Abstract

The utility model relates to a kind of detection device of dryer in air compressor, belong to air handling equipment detection technical field, including power detection component and environmental detection component, environmental detection component includes relay KA1 and several environmental detection elements, and power detection component includes monitoring relay KA2 and monitoring relay KA3;This detection device passes through monitoring relay KA2 and KA3 in power detection component, respectively to fan motor corresponding air switch QF1 and heater corresponding air switch QF2 in real time monitoring is carried out.When air open trips, monitoring relay coil loses power, its normally closed switch is closed, can timely feedback air open trip information, solves the problem that existing dryer local control cabinet cannot effectively monitor air open state.

Description

Technical Field

[0001] This utility model belongs to the field of air handling equipment testing technology, specifically relating to a testing device for the dryer in an air compressor. Background Technology

[0002] In the operation of thermal power plants, the air compressor dryer plays a crucial role in removing moisture from compressed (instrument) air, and its stable operation is directly related to the safety of the thermal power generating unit. Currently, the fan motor and heater inside the air compressor dryer are the core components ensuring the normal operation of the dryer. The fan motor is connected to the power supply in sequence through contactor KM1 and air switch QF1, and the heater is connected to the power supply in sequence through contactor KM2 and air switch QF2.

[0003] However, existing local control cabinets for dryers have serious flaws, failing to effectively monitor whether the circuit breakers (QF1 and QF2) power supply to the motors and heaters have tripped. When these circuit breakers trip, operators lack the necessary monitoring methods to detect this anomaly in a timely manner. This leads to prolonged shutdowns of the motors and heaters, preventing the dryer from performing its dehumidification function properly, and consequently causing water to carry over into the compressed (instrument) air. Water in the compressed (instrument) air can trigger a series of serious problems, such as affecting the normal operation of instrumentation equipment and damaging pneumatic actuators, ultimately severely impacting the safe and stable operation of thermal power generating units. Utility Model Content

[0004] The purpose of this invention is to address the deficiencies in existing technology by providing a detection device for the dryer in an air compressor. The fan motor inside the air compressor dryer is connected to a power source sequentially via contactor KM1 and air switch QF1, and the heater inside the air compressor dryer is connected to a power source sequentially via contactor KM2 and air switch QF2. The detection device includes a power detection component and an environmental detection component. The environmental detection component includes a relay KA1 and several environmental detection elements. The output terminals of the environmental detection elements are all connected to the input terminals of a PLC inside the air compressor dryer. The output terminal of the PLC is connected to the first terminal of the coil of relay KA1, and the second terminal of the coil of relay KA1 is connected to... The neutral wire and the normally open switch of relay KA1 are connected to the DCS system. The power detection component includes monitoring relays KA2 and KA3. The first end of the coil of monitoring relay KA2 is connected to the end of the air switch QF1 corresponding to the fan motor that is furthest from the power source. The second end of the coil of monitoring relay KA2 is connected to the neutral wire. The normally closed switch of monitoring relay KA2 is connected in parallel across the normally open switch of relay KA1. The first end of the coil of monitoring relay KA3 is connected to the end of the air switch QF2 corresponding to the heater that is furthest from the power source. The second end of the coil of monitoring relay KA3 is connected to the neutral wire. The normally closed switch of monitoring relay KA3 is connected in parallel across the normally open switch of relay KA1.

[0005] A further improvement to this technical solution is that the environmental monitoring component includes a temperature sensor BT1, which is installed at the heater to detect the temperature data of the heater; the temperature sensor BT1 is connected to the input terminal of the PLC.

[0006] A further improvement to this technical solution is that the environmental monitoring component also includes a temperature sensor BT2, which is installed at the air inlet of the dryer to detect the air inlet temperature data of the dryer; the temperature sensor BT2 is connected to the input terminal of the PLC.

[0007] A further improvement to this technical solution is that the environmental monitoring component also includes a temperature sensor BT3, which is installed at the outlet of the dryer to detect the outlet temperature data of the dryer; the temperature sensor BT3 is connected to the input terminal of the PLC.

[0008] A further improvement to this technical solution is that the environmental monitoring component also includes a temperature sensor BT4, which is installed at the fan motor of the dryer to detect the intake air temperature data of the fan motor; all temperature sensors BT4 are connected to the input terminal of the PLC.

[0009] Further improvements to this technical solution include the use of infrared temperature sensors of the AST0300 series for temperature sensors BT1, BT2, BT3, and BT4.

[0010] Further improvements to this technical solution include a display screen connected to the PLC for displaying temperature data detected by the environmental sensing element.

[0011] A further improvement to this technical solution is that a thermal relay FH1 is connected in series between the fan motor and the contactor KM1, and the normally closed switch of the thermal relay FH1 is connected in series in the power supply circuit of the contactor KM1 coil.

[0012] A further improvement to this technical solution is that the thermal relay FH1 adopts a Schneider LRD series thermal overload relay, model LRD08C.

[0013] Further improvements to this technical solution include the use of Schneider Electric RM17TA series monitoring relays, model RM17TA00, for both monitoring relays KA2 and KA3.

[0014] The beneficial effects of this utility model are as follows: This detection device uses monitoring relays KA2 and KA3 in the power supply detection component to monitor the air switch QF1 corresponding to the fan motor and the air switch QF2 corresponding to the heater in real time. When the air switch trips, the monitoring relay coil is de-energized, and its normally closed switch closes, which can promptly provide feedback on the air switch tripping information, solving the problem that the existing dryer local control cabinet cannot effectively monitor the status of the air switches.

[0015] The environmental monitoring system incorporates multiple temperature sensors. Temperature sensor BT1 is installed at the heater to monitor its temperature in real time; temperature sensor BT2 is installed at the dryer inlet to detect the inlet air temperature; temperature sensor BT3 is installed at the outlet to obtain the outlet air temperature; and temperature sensor BT4 is installed at the fan motor to detect the fan motor inlet air temperature. These multi-point temperature sensors provide crucial temperature information during dryer operation. Temperature data from different locations reflects the operational status of various parts of the dryer. For example, abnormal heater temperature may affect drying efficiency, inlet and outlet temperature changes reflect drying efficiency, and abnormal fan motor temperature may indicate motor failure. Operators can use this temperature data to promptly identify potential problems and perform maintenance and adjustments in advance to ensure stable dryer operation.

[0016] Furthermore, the design principle of this utility model is reliable, the structure is simple, and it has a very wide range of application prospects.

[0017] It is evident that this utility model has outstanding substantive features and significant progress compared with the prior art, and the beneficial effects of its implementation are also obvious. Attached Figure Description

[0018] To more clearly illustrate the technical solution of this utility model, the drawings used in the description will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is the circuit diagram of the detection device.

[0020] Figure 2 This is a connection diagram for the DCS system. Detailed Implementation

[0021] To make the objectives, features, and advantages of this utility model more apparent and understandable, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings of the specific embodiments. Obviously, the embodiments described below are only some embodiments of this utility model, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0023] In this air compressor dryer system, the core working components are the fan motor and the heater: The power supply circuit of the wind turbine motor is configured as follows: it is connected to a 380V three-phase AC power supply in sequence through contactor KM1 and air switch QF1. Contactor KM1 is used to control the start and stop of the wind turbine motor, and air switch QF1 is used as a short circuit and overload protection element for this circuit. When a short circuit or overload fault occurs in the circuit, QF1 can automatically trip and cut off the power supply to protect the wind turbine motor from damage.

[0024] The power supply circuit of the heater is configured as follows: it is connected to a 380V three-phase AC power supply in sequence through contactor KM2 and air switch QF2. Contactor KM2 is responsible for the on-off control of the heater (the heater temperature protection is connected in series in the circuit of contactor KM2 coil, which is existing technology and will not be described in detail here). Air switch QF2 provides short-circuit and overload protection for the heater circuit to ensure that the heater can be powered off in time under abnormal operating conditions.

[0025] like Figure 1 and Figure 2As shown, this utility model provides a detection device for the dryer in an air compressor, including a power detection component and an environmental detection component. The environmental detection component includes a relay KA1 and several environmental detection elements. The output terminals of the environmental detection elements are all connected to the input terminals of the PLC inside the air compressor dryer. The output terminal of the PLC is connected to the first terminal of the coil of relay KA1, and the second terminal of the coil of relay KA1 is connected to the neutral wire. The normally open switch of relay KA1 is connected to the DCS system. The power detection component includes monitoring relays KA2 and KA3. The first terminal of the coil of monitoring relay KA2 is connected to the end of the air switch QF1 corresponding to the fan motor away from the power source, and the second terminal of the coil of monitoring relay KA2 is connected to the neutral wire. The normally closed switch of monitoring relay KA2 is connected in parallel across the two ends of the normally open switch of relay KA1. The first terminal of the coil of monitoring relay KA3 is connected to the end of the air switch QF2 corresponding to the heater away from the power source, and the second terminal of the coil of monitoring relay KA3 is connected to the neutral wire. The normally closed switch of monitoring relay KA3 is connected in parallel across the two ends of the normally open switch of relay KA1.

[0026] The power detection component is used to monitor the on / off status of the air switches (QF1, QF2) corresponding to the fan motor and heater in real time, and to promptly report air switch tripping faults. It includes monitoring relays KA2 and KA3 (both are Schneider RM17TA series monitoring relays, model RM17TA00).

[0027] Monitoring relay KA2: The first end of its coil is connected via a wire to the end of the air switch QF1 corresponding to the fan motor that is furthest from the power source (i.e., the load-side terminal of QF1, connected to one of the live wires on the furthest end of QF1). The second end of the coil is connected via a wire to the neutral wire (N wire). Since the load side of QF1 carries 220V AC voltage when the air switch is closed (one phase of the three-phase power supply forms a circuit with the neutral wire), the KA2 coil is energized at this time; when QF1 trips due to a fault, its load side loses power, and the KA2 coil loses power.

[0028] Monitoring relay KA3: The first end of its coil is connected via a wire to the end of the air switch QF2 corresponding to the heater that is furthest from the power source (the load-side terminal of QF2 is connected to one of the live wires on the furthest end of QF2). The second end of the coil is connected via a wire to the neutral wire. Similar to KA2, when QF2 is closed, the KA3 coil is energized; when QF2 trips, the KA3 coil is de-energized.

[0029] Normal operating conditions: When both QF1 and QF2 are closed, both KA2 and KA3 coils are energized, and their normally closed switches remain open. At this time, if the temperature data from the environmental detection component is normal, the normally open switch KA1 closes, and the DCS system receives a positive signal; if the temperature data is abnormal, the normally open switch KA1 opens, and the DCS system alarms.

[0030] Circuit breaker tripping fault: If QF1 trips (wind turbine motor loses power), the KA2 coil loses power, and its normally closed switch automatically closes. At this time, regardless of whether the KA1 normally open switch is closed, the DCS system can receive a fault trigger signal through the closed normally closed switch of KA2 (because this circuit is connected in parallel with the KA1 normally open switch, the closure of the normally closed switch is equivalent to short-circuiting the normal signal path of the KA1 normally open switch), and the DCS system immediately triggers an alarm for the wind turbine motor circuit breaker tripping.

[0031] If QF2 trips (heater is de-energized), the KA3 coil loses power and its normally closed switch closes. Similarly, the DCS system triggers an alarm that the heater circuit breaker has tripped.

[0032] If QF1 and QF2 trip simultaneously, and the normally closed switches of KA2 and KA3 both close, the DCS system will trigger a combined alarm that causes the fan motor and heater circuit breaker to trip, indicating that the fault range has expanded and emergency handling is required.

[0033] Specifically, the environmental monitoring component includes temperature sensor BT1, which is installed at the heater to detect the heater's temperature; temperature sensor BT1 is connected to the PLC input. The component also includes temperature sensor BT2, which is installed at the dryer's air inlet to detect the dryer's air inlet temperature; temperature sensor BT2 is connected to the PLC input. Furthermore, the component includes temperature sensor BT3, which is installed at the dryer's air outlet to detect the dryer's air outlet temperature; temperature sensor BT3 is connected to the PLC input. Finally, the component includes temperature sensor BT4, which is installed at the dryer's fan motor to detect the fan motor's air inlet temperature; temperature sensor BT4 is also connected to the PLC input. Temperature sensors BT1, BT2, BT3, and BT4 are all AST0300 series infrared temperature sensors.

[0034] The temperature sensor BT1 uses the AST0300 series infrared temperature sensor. This model of sensor has the advantages of high measurement accuracy (error ±0.5℃), fast response speed (≤100ms), and non-contact measurement, which can avoid damage caused by direct contact with high-temperature components. It is installed in the center of the heater surface, which is the core heating area of ​​the heater, allowing for the most accurate acquisition of the heater's real-time operating temperature, used to determine whether the heater is heating normally or has an overheating fault.

[0035] The temperature sensor BT2 also uses the AST0300 series infrared temperature sensor, which is installed on the inner wall of the air inlet pipe of the dryer and located 5cm downstream of the air inlet. This position can avoid the influence of airflow disturbance at the air inlet on the measurement results and ensure that the initial temperature of the compressed air entering the dryer can be stably collected.

[0036] Temperature sensor BT3 is an AST0300 series infrared temperature sensor, which is installed on the inner wall of the dryer's outlet pipe, 5cm upstream of the outlet, corresponding to the installation position of BT2, and is used to collect the temperature of the compressed air after drying.

[0037] Temperature sensor BT4: The AST0300 series infrared temperature sensor is selected and installed on the outside of the air inlet of the fan motor, 3 to 5 cm away from the motor housing, to collect the temperature of the cooling air entering the fan motor.

[0038] The signal output terminals of the above four temperature sensors are all connected to the analog input terminals of the PLC (Siemens S7-200 series PLC, model CPU 224CN) inside the air compressor dryer via shielded cables (model RVVP-2×0.75mm²).

[0039] When all temperature data detected by all temperature sensors are within the preset normal range (e.g., heater temperature 50 to 80°C, inlet air temperature 20 to 40°C, outlet air temperature 15 to 35°C, fan motor inlet air temperature 15 to 30°C), the PLC's digital output terminal outputs a high-level signal, energizing the coil of relay KA1 (using Omron MY2N-GS series miniature relays).

[0040] When the coil of relay KA1 is energized, its normally open switch closes. This normally open switch is connected to the switch input module of the DCS system (Distributed Control System) of the thermal power plant via a cable, and sends a status signal that the dryer environmental parameters are normal to the DCS system.

[0041] If any temperature sensor detects a temperature data that exceeds the preset normal range (e.g., the heater temperature exceeds 85℃ or falls below 40℃), the PLC's digital output terminal will output a low-level signal, the relay KA1 coil will be de-energized, its normally open switch will open, the DCS system will not receive a normal signal, and an alarm will be automatically triggered (e.g., an audible and visual alarm) to remind operators to troubleshoot the fault in a timely manner.

[0042] To facilitate real-time viewing of temperature data by on-site maintenance personnel, a touch screen (i.e., display screen, selected from Weintek TK6071IP series touch screen) is installed on the local control cabinet of the dryer. The touch screen is connected to the communication port of the PLC via an RS485 communication cable (model RVSP-2×0.75mm²) to display the detection data of the four temperature sensors, the operating status of the PLC, and fault information in real time.

[0043] Furthermore, a thermal relay FH1 is connected in series between the fan motor and the contactor KM1, and the normally closed switch of the thermal relay FH1 is connected in series in the power supply circuit of the contactor KM1 coil.

[0044] To further enhance the operational safety of the wind turbine motor, a thermal relay FH1 (a Schneider LRD series thermal overload relay, model LRD08C, with a setting current range of 0.63 to 1A) is connected in series between the wind turbine motor and the contactor KM1. The heating element of the thermal relay FH1 is connected in series in the main circuit of the wind turbine motor, and its normally closed auxiliary contact is connected in series in the coil power supply circuit of the contactor KM1. When the operating current of the fan motor exceeds 1.2 times the rated current due to reasons such as stall or overload, the heating element of the thermal relay FH1 deforms due to heat, which pushes its normally closed auxiliary contact to open, cutting off the coil power supply circuit of contactor KM1. The main contact of KM1 then opens, and the fan motor is de-energized.

[0045] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A detection device for a dryer in an air compressor, wherein the fan motor inside the air compressor dryer is connected to a power source sequentially via contactor KM1 and air switch QF1, and the heater inside the air compressor dryer is connected to a power source sequentially via contactor KM2 and air switch QF2; characterized in that, The detection device includes a power detection component and an environmental detection component. The environmental detection component includes a relay KA1 and several environmental detection elements. The output terminals of the environmental detection elements are all connected to the input terminals of the PLC inside the air compressor dryer. The output terminal of the PLC is connected to the first terminal of the coil of relay KA1, and the second terminal of the coil of relay KA1 is connected to the neutral wire. The normally open switch of relay KA1 is connected to the DCS system. The power detection component includes monitoring relays KA2 and KA3. The first terminal of the coil of monitoring relay KA2 is connected to the end of the air switch QF1 corresponding to the fan motor that is furthest from the power source. The second terminal of the coil of monitoring relay KA2 is connected to the neutral wire. The normally closed switch of monitoring relay KA2 is connected in parallel across the normally open switch of relay KA1. The first terminal of the coil of monitoring relay KA3 is connected to the end of the air switch QF2 corresponding to the heater that is furthest from the power source. The second terminal of the coil of monitoring relay KA3 is connected to the neutral wire. The normally closed switch of monitoring relay KA3 is connected in parallel across the normally open switch of relay KA1.

2. The detection device for the dryer in an air compressor according to claim 1, characterized in that, The environmental monitoring component includes a temperature sensor BT1, which is installed at the heater to detect the heater's temperature data; the temperature sensor BT1 is connected to the input terminal of the PLC.

3. The detection device for the dryer in an air compressor according to claim 2, characterized in that, The environmental monitoring component also includes a temperature sensor BT2, which is installed at the air inlet of the dryer to detect the air inlet temperature data of the dryer; the temperature sensor BT2 is connected to the input terminal of the PLC.

4. The detection device for the dryer in an air compressor according to claim 3, characterized in that, The environmental monitoring component also includes a temperature sensor BT3, which is installed at the outlet of the dryer to detect the outlet temperature data of the dryer; the temperature sensor BT3 is connected to the input terminal of the PLC.

5. The detection device for the dryer in an air compressor according to claim 4, characterized in that, The environmental monitoring component also includes a temperature sensor BT4, which is installed at the fan motor of the dryer to detect the intake air temperature data of the fan motor; all temperature sensors BT4 are connected to the input terminal of the PLC.

6. The detection device for the dryer in an air compressor according to claim 5, characterized in that, Temperature sensors BT1, BT2, BT3 and BT4 all use infrared temperature sensors of the AST0300 series.

7. The detection device for the dryer in an air compressor according to claim 1, characterized in that, It also includes a display screen, which is connected to the PLC to display temperature data detected by the environmental sensing element.

8. The detection device for the dryer in an air compressor according to claim 1, characterized in that, A thermal relay FH1 is connected in series between the fan motor and the contactor KM1. The normally closed switch of the thermal relay FH1 is connected in series in the power supply circuit of the contactor KM1 coil.

9. The detection device for the dryer in an air compressor according to claim 8, characterized in that, The thermal relay FH1 is a Schneider LRD series thermal overload relay, model LRD08C.

10. The detection device for the dryer in an air compressor according to claim 1, characterized in that, Both monitoring relays KA2 and KA3 use Schneider Electric RM17TA series monitoring relays, model RM17TA00.

Images