CN211603493U - DC power supply aging degree detection device - Google Patents

Abstract

The utility model discloses a DC power supply ageing degree detection device, including exchanging millivoltmeter, direct-current voltmeter, working power supply, direct current ammeter, sampling resistor, zener diode, selector switch, first electric capacity and load resistance, signal input part positive pole, first electric capacity, sampling resistor, direct current ammeter and signal input part negative pole are established ties in proper order, zener diode, sampling resistor and exchanging millivoltmeter's sample end is parallelly connected each other and is formed parallel circuit, load resistance connects in parallel in the series circuit that first electric capacity and sampling resistor establish ties into, and direct-current voltmeter's sample end is parallelly connected with monitoring devices's signal input part, and working power supply and exchanging millivoltmeter, direct-current voltmeter and direct-current ammeter's work power end are parallelly connected. The device detects the output ripple size of the power supply module through the test circuit, compares the output ripple size with a set threshold value, judges the aging degree of the switching power supply, ensures the normal operation of equipment, and improves the reliability of the equipment.

Description

A DC power supply aging detection device

technical field

The utility model relates to a power protection device, in particular to an aging degree detection device of a direct current power supply.

Background technique

Compared with the traditional linear regulated power supply, the switching power supply module has the advantages of small size, high efficiency, low cost and high degree of automation, so it is widely used in the field of industrial control. However, the switching power supply also has obvious shortcomings, that is, the aging speed is fast, which may bring hidden dangers to the power supply equipment. The DC voltage output by the switching power supply is originally a series of pulse voltages with a certain duty cycle. Only after smoothing by the filter capacitor at the output end can it become a smooth DC voltage for the load to use. After the capacitor ages, its dielectric loss angle will increase significantly, so that the ability to pass high-order AC components will decrease, and its capacitance will also decrease, thereby increasing the discharge speed. Therefore, once the filter capacitor of the switching power supply is aging, it can be clearly seen from the increase in the fluctuation degree of the output voltage waveform. However, the existing technology cannot detect the output ripple of the power module to determine the aging degree of the DC power supply, so it is difficult to effectively solve the switching problem. The hidden danger caused by the aging of the power supply.

SUMMARY OF THE INVENTION

The utility model mainly solves the technical problem that the prior art cannot detect the output ripple of the power supply module, and provides a DC power supply aging degree detection device, which detects the output ripple of the power supply module through a test circuit, and compares it with a set threshold to determine the switch The aging degree of the power supply ensures the normal operation of the equipment and improves the reliability of the equipment.

The above-mentioned technical problems of the present utility model are mainly solved by the following technical solutions: the present utility model includes an AC millivoltmeter, a DC voltmeter, a working power supply, a DC ammeter, a sampling resistor, a zener diode, a selection switch, and a first capacitor. and load resistance, the positive pole of the signal input terminal, the first capacitor, the sampling resistance, the DC ammeter and the negative pole of the signal input terminal are connected in series in sequence, and the zener diode, the sampling resistance and the sampling terminal of the AC millivoltmeter are connected in parallel with each other to form a parallel circuit, The load resistor is connected in parallel with the series circuit formed by the first capacitor and the sampling resistor in series, the sampling terminal of the DC voltmeter is connected in parallel with the signal input terminal of the monitoring device, and the working power supply is connected to the working power supply of the AC millivoltmeter, the DC voltmeter and the DC ammeter. terminals in parallel. The load resistor is used to provide different loads to compare the output voltage ripple value and accurately distinguish bad power modules. The Zener diode is used to prevent the AC millivolt meter from being damaged by the inrush current of the meter connected to the instantaneous capacitor charging. The first capacitor is used to isolate the DC component to facilitate the measurement of the AC component. The sampling resistor is used to discharge the conductance current of the capacitor and complete the sampling. An AC millivoltmeter is used to measure the magnitude of the ripple voltage.

Preferably, it includes a second capacitor, a selection switch is provided between the first capacitor and the positive terminal of the signal input terminal, the static contact of the selection switch is connected to the positive terminal of the signal input terminal, and the two movable contacts of the selection switch are respectively connected to the positive terminal of the signal input terminal. One end of the first capacitor is connected to one end of the second capacitor, the other end of the second capacitor is connected to the other end of the first capacitor, and the first capacitor and the second capacitor have different capacities. The capacities of the two capacitors are different, so as to measure the voltage ripple value of different frequencies, one measures the power frequency and the other measures the high frequency, which further improves the detection effect.

Preferably, the working power source includes a solar panel and a battery. The working power is generated by solar panels, which increases the continuous working time of the detection device, and the battery ensures the current stability of the detection device.

Preferably, the first capacitor and the second capacitor are electrolytic capacitors. The positive electrode of the electrolytic capacitor is connected to the selection switch, and the negative electrode of the electrolytic capacitor is connected to the sampling resistor, which is used to deal with high-frequency current.

Preferably, the resistance value of the load resistor is freely adjustable within 0 ohms to 200 ohms. The load resistor provides different loads for the detection circuit to compare the output voltage ripple value and accurately distinguish bad power modules.

The beneficial effect of the utility model is that the output ripple of the power supply module is detected by the test circuit, and the aging degree of the switching power supply is judged by comparing with the set threshold, so as to ensure the normal operation of the equipment and improve the reliability of the equipment.

Description of drawings

Figure 1 is a circuit diagram of the present utility model.

In the figure, 1 AC millivolt meter, 2 DC voltmeter, 3 working power supply, 4 DC ammeter, 5 sampling resistor, 6 Zener diode, 7 first capacitor, 8 second capacitor, 9 load resistor, 10 selection switch, 20 signal input

Detailed ways

The technical solutions of the present utility model will be further described in detail below through embodiments and in conjunction with the accompanying drawings.

Embodiment: A DC power supply aging detection device of this embodiment, as shown in FIG. 1, includes an AC millivolt meter 1, a DC voltmeter 2, a working power supply 3, a DC ammeter 4, a sampling resistor 5, and a Zener diode 6. , a selection switch 10 , a first capacitor 7 , a second capacitor 8 and a load resistor 9 . Zener diode 6, sampling resistor 5 and the sampling terminals of AC millivolt meter 1 are connected in parallel to form a parallel circuit. Zener diode 6 is used to prevent the meter from being damaged by the inrush current of the instantaneous capacitor charging when the meter is connected; sampling resistance 5 is used for The conductance current of the discharge capacitor is used to complete the sampling; the AC millivoltmeter is used to measure the magnitude of the ripple voltage. There is a selection switch 10 between the sampling resistor 1.5 and the positive pole of the signal input terminal 20, the static contact of the selection switch 10 is connected to the positive pole of the signal input terminal 20, and the two movable contacts of the selection switch 10 are respectively connected with the first capacitor 7 and the second The capacitors 8 are connected, the first capacitor 7 and the second capacitor 8 are used to isolate the DC component to facilitate the measurement of the AC component, and the first capacitor 7 and the second capacitor 8 have different capacities and are used to measure the voltage ripple value of different frequencies. One measurement The power frequency is one for measuring high frequency, which further improves the detection effect. The load resistor 9 is used to provide different loads for the detection circuit to compare the output voltage ripple value and accurately distinguish the bad power modules. The DC ammeter 4 is connected in series between the sampling resistor 5 and the negative pole of the signal input terminal 20 of the monitoring device, and the sampling terminal of the DC voltmeter 2 is connected in parallel with the signal input terminal 20 of the detection device for measuring DC current and DC voltage values. The working power supply 3 is connected in parallel with the working power supply terminals of the AC millivolt meter 1, the DC voltmeter 2 and the DC ammeter 4 to provide power for the AC millivolt meter 1, the DC voltmeter 2 and the DC ammeter 4. The working power supply 3 includes a solar cell The working power source 3 generates electricity through the solar panel, which increases the continuous working time of the detection device, and the battery ensures the current stability of the detection device.

The DC voltage output by the switching power supply is originally a series of pulse voltages with a certain duty cycle. Only after smoothing by the filter capacitor at the output end can it become a smooth DC voltage for the load to use. After the capacitor ages, its dielectric loss will increase significantly, so that the ability of the capacitor to pass high-order AC components will decrease, and its capacitance will also decrease, thereby increasing the discharge speed. Therefore, once the filter capacitor of the switching power supply ages, its output voltage The fluctuation degree of the waveform will increase significantly, and the aging degree of the DC power supply can be judged by detecting the output ripple of the power module.

When working, use the first capacitor 7 and the second capacitor 8 to isolate the DC component, add a load resistor 9 to the detection circuit to provide different loads for the detection circuit, discharge the conductance current of the capacitor through the sampling resistor 5 and complete the sampling, you can pass and The AC millivolt meter 1 connected in parallel with the sampling resistor 5 measures the magnitude of the ripple voltage. At the same time, a zener diode 6 is added to the monitoring circuit to prevent the AC millivolt meter from being damaged by the inrush current of the meter connected to the instantaneous capacitor charging. Connected to measure voltage ripple values at different frequencies, one for power frequency and one for high frequency, to further improve the detection effect. The DC ammeter 4 connected in series between the sampling resistor 1.5 and the negative electrode of the signal input terminal 10 of the monitoring device and the DC voltmeter 2 connected in parallel with the signal input terminal 20 are used to measure DC current and DC voltage values.

Claims (5)

1. A direct-current power supply aging degree detection device is characterized by comprising an alternating-current millivoltmeter (1), a direct-current voltmeter (2), a working power supply (3), a direct-current ammeter (4), a sampling resistor (5), a voltage stabilizing diode (6), a selection switch (10), a first capacitor (7), a signal input end (20) and a load resistor (9), wherein the anode of the signal input end (20), the first capacitor (7), the sampling resistor (5), the direct-current ammeter (4) and the cathode of the signal input end (20) are sequentially connected in series, the voltage stabilizing diode (6), the sampling resistor (5) and the sampling end of the alternating-current millivoltmeter (1) are connected in parallel to form a parallel circuit, the load resistor (9) is connected in parallel to a series circuit formed by the first capacitor (7) and the sampling resistor (5) in series, the sampling end of the direct-current voltmeter (2) is connected in parallel to the signal input end (20) of a monitoring device, the working power supply (3) is connected in parallel with the working power supply ends of the alternating-current millivoltmeter (1), the direct-current voltmeter (2) and the direct-current ammeter (4).

2. The direct current power supply aging degree detection device according to claim 1, characterized by comprising a second capacitor (8), wherein a selection switch (10) is arranged between the first capacitor (7) and the positive electrode of the signal input end (20), a fixed contact of the selection switch (10) is connected with the positive electrode of the signal input end (20), two movable contacts of the selection switch (10) are respectively connected with one end of the first capacitor (7) and one end of the second capacitor (8), the other end of the second capacitor is connected with the other end of the first capacitor, and the first capacitor (7) and the second capacitor (8) have different capacities.

3. The direct current power supply degradation detection device according to claim 1, wherein the operating power supply (3) comprises a solar panel and a storage battery.

4. A dc power supply degradation detection device according to claim 2, wherein the first capacitor (7) and the second capacitor (8) are electrolytic capacitors.

5. The dc power supply degradation detection device according to claim 2, wherein the resistance of the load resistor (9) is freely adjustable within a range of 0 ohm to 200 ohm.

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