CN203552101U - An explosion-proof inverter moisture removal device - Google Patents

Abstract

The utility model provides an explosion-proof frequency converter removes damp device, belongs to transformer or distribution technical field for solve the electric leakage problem of colliery explosion-proof frequency converter in the pit, its technical scheme is, it includes temperature signal acquisition circuit, humidity signal acquisition circuit, singlechip, power contactor and dehumidification circuit, the signal output part of temperature signal acquisition circuit and humidity signal acquisition circuit connects the different input ports of singlechip respectively, and two control signal output ports of singlechip connect the control coil of power contactor and the control signal input part of dehumidification circuit respectively through darlington transistor array, power contactor's normally open contact concatenates in explosion-proof frequency converter's power supply loop. The utility model discloses can prevent effectively that the colliery is explosion-proof converter in the pit because of the moist electric leakage, avoid the various incident that cause from this, prolong explosion-proof converter's life, ensure the normal operating of colliery production.

Description

An explosion-proof inverter moisture removal device

technical field

The utility model relates to a moisture removal device used inside an explosion-proof frequency converter in a coal mine, belonging to the technical field of power transformation or power distribution. the

Background technique

At present, explosion-proof frequency converters are used more and more underground in coal mines. Due to the high humidity in the operating environment, after the underground explosion-proof frequency converter is stopped for a period of time, the insulation level of its internal components will drop significantly, resulting in leakage when it is restarted. If the phenomenon is serious, it may cause the explosion-proof frequency converter to explode, causing a major safety accident and bringing irreparable economic losses to the enterprise. Therefore, how to effectively prevent the leakage of the underground explosion-proof frequency converter in coal mines and ensure the normal operation of coal mine production has become a difficult problem for relevant technical personnel.

Utility model content

The purpose of this utility model is to provide an explosion-proof frequency converter moisture removal device for the drawbacks of the prior art, so as to prevent the leakage of the explosion-proof frequency converter underground in coal mines and ensure the normal operation of coal mine production.

Problem described in the utility model is realized with following technical scheme:

An explosion-proof frequency converter dehumidification device, comprising a temperature signal acquisition circuit, a humidity signal acquisition circuit, a single-chip microcomputer, a power contactor and a dehumidification circuit, the signal output terminals of the temperature signal acquisition circuit and the humidity signal acquisition circuit are respectively connected to the single-chip microcomputer Different input ports, the two control signal output ports of the single chip microcomputer are respectively connected to the control coil of the power contactor and the control signal input end of the dehumidification circuit through the Darlington transistor array, and the normally open contacts of the power contactor are connected in series to the explosion-proof frequency conversion In the power supply circuit of the device.

The above-mentioned dehumidification device for explosion-proof frequency converter, the dehumidification circuit includes a rubber-sealed transformer, a dehumidification contactor and a heater installed inside the explosion-proof frequency converter, the control coil of the dehumidification contactor is connected to the output end of the Darlington transistor array, the The primary side coil of the rubber-sealed transformer is connected to the power supply voltage, and the secondary side coil is connected to the heater through the normally open contact of the dehumidification contactor.

In the above-mentioned explosion-proof frequency converter dehumidification device, the humidity signal acquisition circuit includes a humidity sensor and a humidity signal conditioning circuit. The humidity sensor is installed inside the explosion-proof frequency converter, and its output signal is connected to the input port of the single-chip microcomputer through the humidity signal conditioning circuit.

The above-mentioned explosion-proof frequency converter moisture removal device, the temperature signal acquisition circuit includes a temperature sensor and a temperature signal conditioning circuit, the temperature sensor is installed inside the explosion-proof frequency converter, and its output signal is connected to the input port of the single-chip microcomputer through the temperature signal conditioning circuit.

The above-mentioned explosion-proof frequency converter moisture removal device, the structure of the humidity signal conditioning circuit and the temperature signal conditioning circuit are the same, both of which are composed of an operational amplifier, a voltage regulator tube, two capacitors and three resistors, and the operational amplifier is connected to form a voltage The output terminal of the follower is connected to the input port of the single-chip microcomputer, and the output signal of the humidity sensor or the temperature sensor is divided by a voltage divider circuit formed by connecting the first resistor and the second resistor in series, and then connected to the input terminal of the voltage follower through the third resistor, After the regulator tube and the two capacitors are connected in parallel, one end is grounded, and the other end is connected to the series connection point of the first resistor and the second resistor.

The above-mentioned explosion-proof frequency converter moisture removal device also includes a circulating fan installed in the explosion-proof frequency converter and connected in parallel with the heater.

In the above explosion-proof frequency converter moisture removal device, the control coils of the power contactor and the dehumidification contactor are both connected in parallel with freewheeling diodes.

In the above-mentioned explosion-proof frequency converter moisture removal device, the heater adopts an input reactor installed inside the explosion-proof frequency converter.

In the utility model, the insulation level of the explosion-proof frequency converter must be judged according to its internal humidity and temperature detection values before each startup. When the insulation level meets the requirements, the power supply circuit of the explosion-proof inverter is connected, which effectively prevents the leakage of the explosion-proof inverter, avoids various safety accidents caused by it, prolongs the service life of the explosion-proof inverter, and ensures coal mine production. of normal operation.

Description of drawings

Below in conjunction with accompanying drawing, the utility model is further described.

Fig. 1 is the electric principle block diagram of the present utility model;

Figure 2 is an electrical schematic diagram.

The list of labels in the figure is: U1, single-chip microcomputer; U2, Darlington transistor array; F, operational amplifier; Te, temperature sensor; S, humidity sensor; T, glue-sealed transformer; J1, power contactor; J2, dehumidification contact TL-1, temperature signal conditioning circuit; TL-2, humidity signal conditioning circuit; R1, first resistor; R2, second resistor; R3, third resistor; C1, first capacitor; C2, second capacitor; DW, regulator tube; D1, first freewheeling diode; D2, second freewheeling diode; H, heater; M, circulation fan.

Detailed ways

The utility model has the function of removing moisture, which can restore the explosion-proof frequency converter to the normal insulation level, and avoid safety accidents caused by damp.

Referring to Fig. 1 and Fig. 2, the utility model includes a temperature signal acquisition circuit, a humidity signal acquisition circuit, a single-chip microcomputer U1, a power contactor J1 and a dehumidification circuit. Among them, the temperature signal acquisition circuit includes a temperature sensor Te and a temperature signal conditioning circuit TL-1, the humidity signal acquisition circuit includes a humidity sensor S and a temperature signal conditioning circuit TL-2, and the dehumidification circuit includes a glue-sealed transformer T, a dehumidification contactor J2, a heating Device H and circulation fan M. The temperature signal conditioning circuit TL-1 and the temperature signal conditioning circuit TL-2 have the same structure, and are composed of an operational amplifier F, a first resistor R1, a second resistor R2, a third resistor R3, a first capacitor C1, a second capacitor C2 and Composed of a voltage regulator tube DW, the first resistor R1 and the second resistor R2 form a voltage divider circuit for adjusting the signal amplitude, the first capacitor C1 and the second capacitor C2 are used to filter out interference signals, and the voltage regulator tube DW acts as a limiter Function, the third resistor R3 is a coupling resistor, and the operational amplifier F is connected as a voltage follower, the purpose is to reduce the output impedance of the signal acquisition circuit. Darlington transistor array U2 is a large current drive array, which can directly drive loads such as relays.

Working principle of the utility model:

After the underground explosion-proof frequency converter of the coal mine is stopped and left for a period of time, the dehumidification device starts to work before the power is turned on again. First, the temperature sensor Te detects the internal temperature of the explosion-proof frequency converter, and the humidity sensor S detects the internal humidity of the explosion-proof frequency converter. The two signals are processed by their respective conditioning circuits and sent to the single-chip microcomputer U1. The single-chip microcomputer U1 analyzes the explosion-proof frequency conversion in coal mines according to these two signals. Insulation level inside the device. If any of the temperature, humidity or insulation level exceeds the set threshold, the device immediately blocks the input circuit of the explosion-proof inverter through the power contactor J1, and at the same time the normally open contact of the dehumidification contactor J2 is closed, the heater H and The circulation fan M starts to work. At this time, the heater H is used as the load of the rubber-sealed transformer T. The circulation fan M blows away the heat from the heater H, and makes the hot air circulate inside the explosion-proof inverter to realize the dehumidification function. After the detected temperature, humidity and insulation level are all within the set range, the device will delay the operation for another 5 minutes, then stop working, release the power supply lock at the input end of the inverter, and make the explosion-proof inverter enter the normal working state.

Claims (8)

1. An explosion-proof frequency converter dehumidification device, characterized in that it includes a temperature signal acquisition circuit, a humidity signal acquisition circuit, a single-chip microcomputer (U1), a power contactor (J1) and a dehumidification circuit, and the temperature signal acquisition circuit and humidity The signal output terminals of the signal acquisition circuit are respectively connected to different input ports of the single-chip microcomputer (U1), and the two control signal output ports of the single-chip microcomputer (U1) are respectively connected to the control coil and the power contactor (J1) via the Darlington transistor array (U2). The control signal input end of the dehumidification circuit, the normally open contact of the power contactor (J1) is connected in series with the power supply circuit of the explosion-proof frequency converter. 2. An explosion-proof inverter dehumidification device according to claim 1, characterized in that the dehumidification circuit includes a rubber-sealed transformer (T), a dehumidification contactor (J2) and a heater installed inside the explosion-proof inverter (H), the control coil of the dehumidification contactor (J2) is connected to the output terminal of the Darlington transistor array (U2), the primary coil of the rubber-encapsulated transformer (T) is connected to the power supply voltage, and the secondary coil is connected to the dehumidification contact The normally open contact of the heater (J2) contacts the heater (H). 3. An explosion-proof inverter dehumidification device according to claim 1 or 2, characterized in that the humidity signal acquisition circuit includes a humidity sensor (S) and a humidity signal conditioning circuit (TL-2), and the humidity The sensor (S) is installed inside the explosion-proof frequency converter, and its output signal is connected to the input port of the single-chip microcomputer (U1) through the humidity signal conditioning circuit (TL-2). 4. An explosion-proof frequency converter moisture removal device according to claim 3, characterized in that, the temperature signal acquisition circuit includes a temperature sensor (Te) and a temperature signal conditioning circuit (TL-1), and the temperature sensor ( Te) is installed inside the explosion-proof inverter, and its output signal is connected to the input port of the single-chip microcomputer (U1) through the temperature signal conditioning circuit (TL-1). 5. An explosion-proof inverter dehumidification device according to claim 4, characterized in that the structure of the humidity signal conditioning circuit (TL-2) and the temperature signal conditioning circuit (TL-1) are the same, both It consists of an operational amplifier (F), a regulator tube (DW), two capacitors and three resistors. The operational amplifier (F) is connected as a voltage follower, and its output terminal is connected to the input port of the single-chip microcomputer (U1). The humidity sensor (S) or the output signal of the temperature sensor (Te) is divided by the voltage divider circuit formed by the first resistor (R1) and the second resistor (R2) connected in series, and then connected to the input terminal of the voltage follower through the third resistor (R3) , the regulator tube (DW) and two capacitors are connected in parallel, one end is grounded, and the other end is connected to the series connection point of the first resistor (R1) and the second resistor (R2). 6. An explosion-proof inverter moisture removal device according to claim 5, characterized in that the composition also includes a circulation fan (M), and the circulation fan (M) is installed inside the explosion-proof inverter and connected to the heater (H) Parallel connection. 7. The dehumidification device for an explosion-proof frequency converter according to claim 6, characterized in that, the control coils of the power contactor (J1) and the dehumidification contactor (J2) are connected in parallel with freewheeling diodes. 8. An explosion-proof inverter moisture removal device according to claim 7, characterized in that the heater (H) adopts an input reactor installed inside the explosion-proof inverter.

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