CN218971475U - Direct-current axial flow fan fault detection circuit and direct-current axial flow fan assembly - Google Patents
Direct-current axial flow fan fault detection circuit and direct-current axial flow fan assembly Download PDFInfo
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- CN218971475U CN218971475U CN202223294178.0U CN202223294178U CN218971475U CN 218971475 U CN218971475 U CN 218971475U CN 202223294178 U CN202223294178 U CN 202223294178U CN 218971475 U CN218971475 U CN 218971475U
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Abstract
The utility model belongs to the technical field of fault detection, and discloses a direct-current axial-flow fan fault detection circuit and a direct-current axial-flow fan assembly. The direct-current axial-flow fan fault detection circuit comprises a fan current sampling circuit, a current waveform shaping circuit and a fault indication circuit; the fan current sampling circuit is used for extracting alternating current components in the working current of the direct current axial flow fan and sending the alternating current components to the current waveform shaping circuit; the current waveform shaping circuit compares the alternating component in the received direct-current axial-flow fan working current with a voltage reference, outputs a fan working pulse signal related to the direct-current axial-flow fan working current waveform, and sends the fan working pulse signal to the fault indication circuit; the fault indication circuit converts the received fan working pulse signal into an optical signal and outputs a corresponding fault detection signal. The utility model can monitor the working state of the direct current axial flow fan in real time, can give an alarm in real time and accurately position the direct current axial flow fan in the daily working state, and is convenient for overhauling and maintenance.
Description
Technical Field
The utility model belongs to the technical field of fault detection, and particularly relates to a direct-current axial-flow fan fault detection circuit and a direct-current axial-flow fan assembly.
Background
The high-power switching power supply provides required direct current power for a TR component and the like of the radar. The cooling mode of the switching power supply mainly comprises liquid cooling and forced air cooling.
The working principle of forced air cooling is that the heat of a heating device in the switch power supply is transferred to natural wind through an air cooling fin cold plate under the action of conduction and convection, the wind temperature is increased, the switch power supply is discharged through an axial flow fan exhausting mode, and the heat is dissipated into the outside air.
The over-temperature protection of the existing switching power supply is to collect the temperature of the air-cooled fin cold plate, if a cooling fan fails, when the temperature of the cold plate is higher than the set temperature, the power supply is turned off until the temperature is reduced, and then the power supply resumes working. The power supply is in a closed and working cycle state, and the power supply is easy to fail.
Disclosure of Invention
The utility model aims at: aiming at the defects of the prior art, the direct-current axial flow fan fault detection circuit and the direct-current axial flow fan assembly are provided, the working state of the direct-current axial flow fan providing a cooling function for a high-power switching power supply can be monitored in real time, detection signals are sent to a control and protection unit for fault early warning, and the fault positioning is convenient for workers in time and accurately.
Specifically, the utility model is realized by adopting the following technical scheme.
In one aspect, the utility model provides a direct current axial flow fan fault detection circuit, which comprises a fan current sampling circuit, a current waveform shaping circuit and a fault indication circuit;
the fan current sampling circuit is used for extracting alternating current components in the working current of the direct current axial flow fan and sending the alternating current components to the current waveform shaping circuit;
the current waveform shaping circuit compares the alternating component in the received direct-current axial-flow fan working current with a voltage reference, outputs a fan working pulse signal related to the direct-current axial-flow fan working current waveform, and sends the fan working pulse signal to the fault indication circuit;
the fault indication circuit converts the received fan working pulse signal into an optical signal and outputs a corresponding fault detection signal.
Further, the fan current sampling circuit is composed of a first resistor and a filter circuit, the filter circuit comprises a first capacitor and a second resistor, the first resistor is connected in series in a power supply loop of the direct-current axial-flow fan, and after the fan working current waveform on the first resistor passes through the filter circuit, an alternating-current component is extracted and sent to the current waveform shaping circuit.
Further, the current waveform shaping circuit consists of an operational amplifier and a voltage dividing circuit; the positive power end of the operational amplifier is connected with an auxiliary power supply, and the negative power supply is grounded; one end of the second capacitor is connected with the auxiliary power supply, and the other end of the second capacitor is grounded; the voltage dividing circuit is composed of a third resistor and a first potentiometer, is connected to the in-phase input end of the operational amplifier as a voltage reference, and fan working current alternating current components output by the fan current sampling circuit are connected to the inverting input end of the operational amplifier, and output fan working pulse signals after comparison operation of the operational amplifier and are sent to the fault indicating circuit.
Further, the fault indication circuit comprises a fourth resistor, a protection diode, a light emitting diode and an optocoupler; one end of the fourth resistor is connected with a fan working pulse signal, and the other end of the fourth resistor is connected with the anode of the light-emitting diode; the LED is connected in series with the diode end of the optocoupler and then connected in inverse parallel with the protection diode; the triode end of the optical coupler outputs a fault detection signal.
Further, the direct-current axial flow fan fault detection circuit further comprises a current waveform pulse widening circuit; and fan working pulse signals output by the current waveform shaping circuit pass through the current waveform pulse stretching circuit to obtain stretched fan working pulse signals, and the stretched fan working pulse signals are sent to the fault indication circuit.
Further, the current waveform pulse stretching circuit consists of a monostable multivibrator, a second potentiometer and a third capacitor;
the positive power supply end of the monostable multivibrator is connected with an auxiliary power supply, and the negative power supply end is grounded; the fan working pulse signal output by the current waveform shaping circuit is connected to the positive trigger input end of the monostable multivibrator, and the positive pulse output end is connected with the fault indication circuit;
one end of the second potentiometer is connected with a pin RCext of the monostable multivibrator, and the other end of the second potentiometer is connected with an auxiliary power supply;
one end of the third capacitor is connected with the pin Cext of the monostable multivibrator, and the other end of the third capacitor is connected with the pin RCext of the monostable multivibrator.
On the other hand, the utility model also provides a direct-current axial-flow fan assembly, which comprises at least two direct-current axial-flow fans, a direct-current axial-flow fan fault detection circuit corresponding to the direct-current axial-flow fans, a power switch of the direct-current axial-flow fan assembly and a connector;
the direct-current axial flow fan assembly adopts a redundant design, and can meet set wind pressure and wind speed after an individual axial flow fan in the direct-current axial flow fan assembly fails;
the direct-current axial-flow fan fault detection circuit is the direct-current axial-flow fan fault detection circuit;
the power switch of the direct-current axial flow fan assembly controls the start and stop of the work of the direct-current axial flow fan;
the connector provides direct current power supply required by the direct current axial flow fan assembly and outputs fault detection signals.
The beneficial effects of the utility model are as follows:
by adopting the direct-current axial-flow fan fault detection circuit and the direct-current axial-flow fan assembly, the working state of the axial-flow fan can be monitored in real time, and the direct-current axial-flow fan with faults can be accurately positioned after the cooling fan has faults, so that the switching power supply can be conveniently and timely turned off, and the switching power supply can be rapidly and accurately protected.
By adopting the direct-current axial-flow fan fault detection circuit and the direct-current axial-flow fan assembly, when the direct-current axial-flow fan works normally, the pulse high level output by the optocoupler is related to the rotating speed of the direct-current axial-flow fan. When the direct-current axial flow fans stop running or age after long-time use to cause the rotation speed of the axial flow fans to decrease, the frequency of the pulse signals output by the optocouplers in the fault detection circuit of the direct-current axial flow fans also can be reduced, and the working state of each direct-current axial flow fan can be timely and accurately judged, so that preventive maintenance can be carried out.
Drawings
Fig. 1 is a schematic diagram of a fault detection circuit of a dc axial flow fan according to an embodiment of the present utility model.
Fig. 2 is a schematic diagram of signal waveforms of each endpoint of the fault detection circuit of the direct current axial flow fan according to an embodiment of the present utility model.
Fig. 3 is a schematic diagram of a fault detection circuit (including a current waveform pulse stretching circuit) of a dc axial flow fan according to an embodiment of the present utility model.
Fig. 4 is a schematic diagram of waveforms of signals at each end point of a fault detection circuit (including a current waveform pulse stretching circuit) of a dc axial flow fan according to an embodiment of the present utility model.
Fig. 5 is a schematic view of a dc axial fan assembly according to an embodiment of the present utility model.
Detailed Description
The utility model is described in further detail below with reference to the examples and with reference to the accompanying drawings.
Example 1:
an embodiment of the utility model relates to a direct current axial flow fan fault detection circuit which is used for monitoring the working state of an axial flow fan in real time and accurately positioning the direct current axial flow fan with faults when a cooling fan is in fault.
The direct current axial flow fan fault detection circuit of the embodiment comprises a fan current sampling circuit, a current waveform shaping circuit and a fault indication circuit, as shown in fig. 1.
The fan current sampling circuit is used for extracting alternating current components in the working current of the direct current axial flow fan and sending the alternating current components to the current waveform shaping circuit. The fan current sampling circuit consists of a first resistor (R1) and a filter circuit (comprising a first capacitor C1 and a second resistor R2), wherein the first resistor (R1) is connected in series in a power supply loop of the direct-current axial-flow fan, and after fan working current waveforms (waveform A in fig. 2) on the first resistor (R1) pass through the filter circuit (C1 and R2), alternating-current components are extracted and sent to the current waveform shaping circuit (waveform B in fig. 2).
And the current waveform shaping circuit compares the alternating component in the received direct-current axial-flow fan working current with a voltage reference, outputs a fan working pulse signal related to the direct-current axial-flow fan working current waveform, and sends the fan working pulse signal to the fault indication circuit. The current waveform shaping circuit is composed of an operational amplifier (U1) and a voltage dividing circuit. The positive power supply end of the operational amplifier (U1) is connected with an auxiliary power supply Vcc, and the negative power supply end is grounded. One end of the second capacitor C2 is connected with the auxiliary power supply Vcc, and the other end of the second capacitor C is grounded. The voltage dividing circuit is composed of a third resistor (R3) and a first potentiometer (RP 1), one end of the third resistor (R3) is connected with an auxiliary power supply Vcc, the other end of the third resistor is connected with one end of the first potentiometer (RP 1), the other end of the first potentiometer (RP 1) is grounded, a connecting point of the third resistor (R3) and the first potentiometer (RP 1) is connected to a non-inverting input end of an operational amplifier (U1) to serve as a voltage reference, a fan working current alternating current component output by the fan current sampling circuit is connected to an inverting input end of the operational amplifier (U1), a pulse signal related to a fan working current waveform is output after comparison operation of the operational amplifier (U1), and the fan working pulse signal is called as a fan working pulse signal (waveform C in fig. 2) for short and is sent to the fault indicating circuit.
And the fault indication circuit converts the received fan working pulse signal into an optical signal and outputs a corresponding pulse signal (fault detection signal). The fault indication circuit comprises a fourth resistor (R4), a protection diode (D1), a light emitting diode (D2) and an optical coupler (U3). One end of the fourth resistor (R4) is connected with a fan working pulse signal (waveform C in fig. 2), and the other end of the fourth resistor is connected with the anode of the light-emitting diode (D2). The LED (D2) is connected in series with the diode end of the optocoupler (U3) and then is connected in inverse parallel with the protection diode (D1). Specifically, the cathode of the light emitting diode (D2) is connected to the diode-end anode of the optocoupler (U3), and the diode-end cathode of the optocoupler (U3) is connected to ground. The anode of the protection diode (D1) is connected with the diode end cathode of the optocoupler (U3), and the cathode of the protection diode (D1) is connected with the anode of the light-emitting diode (D2). The triode end of the optical coupler (U3) outputs a pulse signal, namely a fault detection signal.
When the direct-current axial flow fan works normally, the fault indication circuit receives continuous fan working pulse signals, the light emitting diode (D2) emits light repeatedly in each period, the optical coupler (U3) is conducted, pulse signals (fault detection signals) are output, and the light emitting diode shows a flicker state. When the direct-current axial-flow fan breaks down, the fault indication circuit cannot receive the fan working pulse signal, the light-emitting diode (D2) does not emit light, the optical coupler (U3) is cut off, no pulse signal is output, and therefore the working state of the direct-current axial-flow fan can be judged through the state (flickering or extinction) of the light-emitting diode (D2) or the existence of the pulse signal output of the optical coupler (U3).
Because the pulse width of the fan working pulse signal output by the current waveform shaping circuit is very narrow, the time for outputting the fault signal is very short, the time for the light emitting diode to present a flickering state is very short, and the human eyes can not notice the fault of the direct current axial flow fan, so that the fault of the direct current axial flow fan is not found in time.
Preferably, in another embodiment, as shown in fig. 3, the fan operation pulse signal output by the current waveform shaping circuit is passed through a current waveform pulse stretching circuit to obtain a stretched fan operation pulse signal (waveform D in fig. 4), and sent to the fault indication circuit. The current waveform pulse stretching circuit is composed of a monostable multivibrator (U2) and peripheral auxiliary devices (a second potentiometer RP2 and a third capacitor C3). The positive power end of the monostable multivibrator (U2) is connected with an auxiliary power supply Vcc, the negative power supply is grounded, the negative trigger input end (A) is grounded, and the reset end (CLR) is connected with the auxiliary power supply Vcc; one end of the second potentiometer (RP 2) is connected with a pin RCext of the monostable multivibrator (U2), and the other end of the second potentiometer is connected with an auxiliary power supply Vcc; one end of the third capacitor (C3) is connected with the pin Cext of the monostable multivibrator (U2), and the other end of the third capacitor is connected with the pin RCext of the monostable multivibrator (U2).
The fan working pulse signal (waveform C in fig. 4) output by the current waveform shaping circuit is connected to the positive trigger input end (B) of the monostable multivibrator, and the positive pulse output end (Q) is connected with one end of the fourth resistor (R4) of the fault indication circuit and is used as an input signal (waveform D in fig. 4) of the fault indication circuit.
The fault indication circuit comprises a fourth resistor (R4), a protection diode (D1), a light emitting diode (D2) and an optical coupler (U3). One end of the fourth resistor (R4) is connected with the fan working pulse signal (waveform D in fig. 4) after being stretched, and the other end of the fourth resistor is connected with the anode of the light-emitting diode (D2). The LED (D2) is connected in series with the diode end of the optocoupler (U3) and then is connected in inverse parallel with the protection diode (D1). Specifically, the cathode of the light emitting diode (D2) is connected to the diode-end anode of the optocoupler (U3), and the diode-end cathode of the optocoupler (U3) is connected to ground. The anode of the protection diode (D1) is connected with the diode end cathode of the optocoupler (U3), and the cathode of the protection diode (D1) is connected with the anode of the light-emitting diode (D2). The triode end of the optical coupler (U3) outputs a pulse signal, namely a fault detection signal. When the direct-current axial flow fan works normally, the fault indication circuit receives a fan working pulse signal after continuous stretching, the light emitting diode (D2) emits light repeatedly in each period, the optical coupler (U3) is conducted, and an indication pulse signal is output. Due to the visual delay effect of the human eye, the light emitting diode is observed to continuously emit light. When the direct-current axial-flow fan breaks down, the fault indication circuit cannot receive the fan working pulse signal, the light-emitting diode (D2) does not emit light, the optical coupler (U3) is cut off, no pulse signal is output, and therefore the working state of the direct-current axial-flow fan can be judged through the state (normally on or off) of the light-emitting diode (D2) or the existence of the pulse signal output of the optical coupler (U3).
Example 2:
another embodiment of the present utility model is a dc axial flow fan assembly employing a dc axial flow fan fault detection circuit.
The direct-current axial flow fan assembly comprises at least two direct-current axial flow fans, a direct-current axial flow fan fault detection circuit corresponding to the direct-current axial flow fans, a direct-current axial flow fan assembly power switch and a connector. A mode of installing a plurality of direct current axial flow fans in one plug box is adopted to provide air cooling sources for other plug boxes. The direct current axial flow fan assembly adopts a redundant design, and after an individual axial flow fan in the direct current axial flow fan assembly fails, the set wind pressure and wind speed can be met, and by utilizing the characteristics of the direct current axial flow fan assembly, different maintenance modes can be determined according to the failure state of the fan. The corresponding direct-current axial-flow fan fault detection circuit of each direct-current axial-flow fan is described in embodiment 1. The power switch SA1 of the direct-current axial-flow fan assembly controls the start and stop of the direct-current axial-flow fan assembly. The connector J1 provides the DC power supply and output fault signals required by the DC axial flow fan assembly.
Taking the direct-current axial-flow fan assembly shown in fig. 3 as an example, as shown in fig. 5, the direct-current axial-flow fan assembly adopts a redundant design, three direct-current axial-flow fans (M1, M2 and M3) are used as wind cooling sources, and after detecting that one direct-current axial-flow fan fails, the set wind pressure and wind speed can be met, and the failure can be recorded without maintenance work. If two direct current axial flow fans are in failure, the work should be stopped immediately and overhauled. The power switch SA1 of the direct-current axial-flow fan assembly controls the start and stop of the work of the direct-current axial-flow fan. The connector J1 provides the DC power supply and output fault signals required by the DC axial flow fan assembly. Three fault detection boards A1-A3 provided with the direct-current axial-flow fan fault detection circuit are adopted to respectively detect the working states of the three direct-current axial-flow fans, and display and report of the working states of the fans are completed.
By adopting the direct-current axial-flow fan fault detection circuit and the direct-current axial-flow fan assembly, the working state of the axial-flow fan can be monitored in real time, and the direct-current axial-flow fan with faults can be accurately positioned after the cooling fan has faults, so that the switching power supply can be conveniently and timely turned off, and the switching power supply can be rapidly and accurately protected.
By adopting the direct-current axial-flow fan fault detection circuit and the direct-current axial-flow fan assembly, when the direct-current axial-flow fan works normally, the pulse high level output by the optocoupler is related to the rotating speed of the direct-current axial-flow fan. When the direct-current axial flow fans stop running or age after long-time use to cause the rotation speed of the axial flow fans to decrease, the frequency of the pulse signals output by the optocouplers in the fault detection circuit of the direct-current axial flow fans also can be reduced, and the working state of each direct-current axial flow fan can be timely and accurately judged, so that preventive maintenance can be carried out.
Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. However, the benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential feature or element of any or all the claims. Furthermore, the particular embodiments disclosed above are illustrative only, as the disclosed subject matter may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. No limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular embodiments disclosed above may be altered or modified and all such variations are considered within the scope of the disclosed subject matter. Accordingly, the protection sought herein is as set forth in the claims below.
Claims (7)
1. The direct-current axial-flow fan fault detection circuit is characterized by comprising a fan current sampling circuit, a current waveform shaping circuit and a fault indication circuit;
the fan current sampling circuit is used for extracting alternating current components in the working current of the direct current axial flow fan and sending the alternating current components to the current waveform shaping circuit;
the current waveform shaping circuit compares the alternating component in the received direct-current axial-flow fan working current with a voltage reference, outputs a fan working pulse signal related to the direct-current axial-flow fan working current waveform, and sends the fan working pulse signal to the fault indication circuit;
the fault indication circuit converts the received fan working pulse signal into an optical signal and outputs a corresponding fault detection signal.
2. The direct current axial flow fan fault detection circuit according to claim 1, wherein the fan current sampling circuit is composed of a first resistor and a filter circuit, the filter circuit comprises a first capacitor and a second resistor, the first resistor is connected in series in a power supply loop of the direct current axial flow fan, and after fan working current waveforms on the first resistor pass through the filter circuit, alternating current components are extracted and sent to the current waveform shaping circuit.
3. The direct current axial flow fan fault detection circuit according to claim 2, wherein the current waveform shaping circuit is composed of an operational amplifier and a voltage dividing circuit; the positive power end of the operational amplifier is connected with an auxiliary power supply, and the negative power supply is grounded; one end of the second capacitor is connected with the auxiliary power supply, and the other end of the second capacitor is grounded; the voltage dividing circuit is composed of a third resistor and a first potentiometer, is connected to the in-phase input end of the operational amplifier as a voltage reference, and fan working current alternating current components output by the fan current sampling circuit are connected to the inverting input end of the operational amplifier, and output fan working pulse signals after comparison operation of the operational amplifier and are sent to the fault indicating circuit.
4. The direct current axial flow fan fault detection circuit of claim 2, wherein the fault indication circuit comprises a fourth resistor, a protection diode, a light emitting diode and an optocoupler; one end of the fourth resistor is connected with a fan working pulse signal, and the other end of the fourth resistor is connected with the anode of the light-emitting diode; the LED is connected in series with the diode end of the optocoupler and then connected in inverse parallel with the protection diode; the triode end of the optical coupler outputs a fault detection signal.
5. The direct current axial flow fan fault detection circuit of claim 1, further comprising a current waveform pulse stretching circuit; and fan working pulse signals output by the current waveform shaping circuit pass through the current waveform pulse stretching circuit to obtain stretched fan working pulse signals, and the stretched fan working pulse signals are sent to the fault indication circuit.
6. The direct current axial flow fan fault detection circuit of claim 5, wherein the current waveform pulse stretching circuit is composed of a monostable multivibrator, a second potentiometer and a third capacitor;
the positive power supply end of the monostable multivibrator is connected with an auxiliary power supply, and the negative power supply end is grounded; the fan working pulse signal output by the current waveform shaping circuit is connected to the positive trigger input end of the monostable multivibrator, and the positive pulse output end is connected with the fault indication circuit;
one end of the second potentiometer is connected with a pin RCext of the monostable multivibrator, and the other end of the second potentiometer is connected with an auxiliary power supply;
one end of the third capacitor is connected with the pin Cext of the monostable multivibrator, and the other end of the third capacitor is connected with the pin RCext of the monostable multivibrator.
7. The direct-current axial-flow fan assembly is characterized by comprising at least two direct-current axial-flow fans, a direct-current axial-flow fan fault detection circuit corresponding to the direct-current axial-flow fans, a direct-current axial-flow fan assembly power switch and a connector;
the direct-current axial flow fan assembly adopts a redundant design, and can meet set wind pressure and wind speed after an individual axial flow fan in the direct-current axial flow fan assembly fails;
the direct-current axial-flow fan fault detection circuit is according to any one of claims 1-6;
the power switch of the direct-current axial flow fan assembly controls the start and stop of the work of the direct-current axial flow fan;
the connector provides direct current power supply required by the direct current axial flow fan assembly and outputs fault detection signals.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202223294178.0U CN218971475U (en) | 2022-12-09 | 2022-12-09 | Direct-current axial flow fan fault detection circuit and direct-current axial flow fan assembly |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223294178.0U CN218971475U (en) | 2022-12-09 | 2022-12-09 | Direct-current axial flow fan fault detection circuit and direct-current axial flow fan assembly |
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| Publication Number | Publication Date |
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| CN218971475U true CN218971475U (en) | 2023-05-05 |
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| CN202223294178.0U Active CN218971475U (en) | 2022-12-09 | 2022-12-09 | Direct-current axial flow fan fault detection circuit and direct-current axial flow fan assembly |
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