CN221804535U - Monitoring device for a switchgear and switchgear - Google Patents

Abstract

The utility model provides a monitoring device for a switch cabinet and a switch cabinet. The monitoring device comprises an input circuit, a micro control unit circuit, and a first digital-to-analog conversion circuit. The input circuit is connected to a measured signal input end of the first analog-to-digital conversion circuit, and an output end of the first analog-to-digital conversion circuit is connected to the micro control unit circuit. The monitoring device for the switch cabinet also comprises: a second analog-to-digital conversion circuit. The input circuit is connected to a measured signal input end of the second analog-to-digital conversion circuit, and an output end of the second analog-to-digital conversion circuit is connected to the micro control unit circuit. The micro control unit circuit is used for simultaneously collecting signals of the first digital-to-analog conversion circuit and the second analog-to-digital conversion circuit.

Description

Monitoring device for switch cabinet and switch cabinet

Technical Field

The utility model relates to the field of power systems, in particular to a monitoring device for a switch cabinet and a switch cabinet.

Background Art

The monitoring equipment used in switch cabinets is often equipped with various circuit boards, among which MCU (Micro Controller Unit) and ADC (Analog to Digital Converter) circuits are often used. The MCU board is used to collect the signal at the output end of the ADC circuit and analyze it to trigger the corresponding subsequent operations.

However, if the ADC circuit fails, an erroneous signal will be generated. The MCU cannot distinguish whether it is an erroneous signal at this time, which may cause erroneous operation.

Utility Model Content

In view of this, the utility model proposes a monitoring device for a switch cabinet, comprising an input circuit, a micro control unit circuit, and a first analog-to-digital conversion circuit, wherein the input circuit is connected to a measured signal input end of the first analog-to-digital conversion circuit, and the output end of the first analog-to-digital conversion circuit is connected to the micro control unit circuit, characterized in that the monitoring device for a switch cabinet further comprises:

A second analog-to-digital conversion circuit, wherein the input circuit is connected to the measured signal input terminal of the second analog-to-digital conversion circuit, the output terminal of the second analog-to-digital conversion circuit is connected to the microcontroller chip, and the microcontroller chip is used to simultaneously collect signals from the first digital-to-analog conversion circuit and the second analog-to-digital conversion circuit.

According to the monitoring device for a switch cabinet of the utility model, the input ends of the two analog-to-digital conversion circuits are connected to the same input circuit, and the output ends of the two analog-to-digital conversion circuits are connected to the same micro-control unit circuit. In this way, the micro-control unit circuit can identify whether one of the conversion circuits is faulty by simultaneously collecting signals from the output ends of the first analog-to-digital conversion circuit and the second analog-to-digital conversion circuit. The method is simple and has high reliability.

According to the monitoring device for switch cabinet as described above, optionally, it further includes: a first reference signal source, the first reference signal source is connected to the reference signal input terminal of the first analog-to-digital conversion circuit. For some situations where high speed is required but not too high precision, the signal output by the first analog-to-digital conversion circuit can be used for analysis.

According to the monitoring device as described above, optionally, the second analog-to-digital conversion circuit corresponds to a second reference signal source, the second reference signal source has a higher precision than the first reference signal source, and the first reference signal source is also connected to the reference signal input terminal of the second analog-to-digital conversion circuit. In this way, the data of the first reference signal source is compared with the data of the second reference signal source to determine the drift degree of the first reference signal source, and then the signal output by the first analog-to-digital conversion circuit can be corrected.

According to the monitoring device as described above, optionally, the first reference signal source and the first analog-to-digital conversion circuit are located in different chips, which can reduce the cost of the chip where the first analog-to-digital conversion circuit is located.

According to the monitoring device as described above, optionally, the first analog-to-digital conversion circuit and the micro control unit circuit are integrated on the same chip, and the chip where the second analog-to-digital conversion circuit is located is different from the chip where the first analog-to-digital conversion circuit is located. Such a configuration can reduce costs.

According to the monitoring device as described above, optionally, the second analog-to-digital conversion circuit has a higher precision than the first analog-to-digital conversion circuit. The analog-to-digital conversion circuit with higher precision makes the analysis result of the micro control unit circuit more accurate.

According to the monitoring device as described above, optionally, it is characterized in that the second analog-to-digital conversion circuit is connected to the micro control unit circuit via SPI. The second analog-to-digital conversion circuit set separately communicates with the micro control unit circuit via SPI, which has good communication effect, strong anti-interference ability and low cost.

The present invention also includes a switch cabinet, which includes the monitoring device for the switch cabinet as described in any of the above items.

BRIEF DESCRIPTION OF THE DRAWINGS

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, so that those skilled in the art will be more aware of the above and other features and advantages of the present invention. In the accompanying drawings:

FIG1 is a partial circuit diagram of a monitoring device for a switch cabinet according to the utility model.

The reference numerals are as follows:

1- Input circuit

2-Micro control unit circuit

3-First analog-to-digital conversion circuit

31-Measured signal input terminal of the first analog-to-digital conversion circuit

32-reference signal input terminal of the first analog-to-digital conversion circuit

33- output terminal of the first analog-to-digital conversion circuit

4- Second analog-to-digital conversion circuit

41-Measured signal input terminal of the second analog-to-digital conversion circuit

42-receiving signal terminal of the second analog-to-digital conversion circuit

43-output terminal of the second analog-to-digital conversion circuit

5-First reference signal source

6-SPI

DETAILED DESCRIPTION

In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model is further described in detail with reference to the following embodiments. The nouns and pronouns related to people in this patent application are not limited to specific genders.

As shown in FIG. 1 , the utility model provides a circuit monitoring device, including an input circuit 1 , a micro control unit circuit 2 , a first analog-to-digital conversion circuit 3 , and a second analog-to-digital conversion circuit 4 .

The input circuit 1 is connected to the measured signal input terminal 31 of the first analog-to-digital conversion circuit 3 and the measured signal input terminal 41 of the second analog-to-digital conversion circuit 4 respectively. The input circuit 1 provides an analog signal, and simultaneously inputs the analog signal into the first analog-to-digital conversion circuit 3 and the second analog-to-digital conversion circuit 4. In this way, the two analog-to-digital conversion circuits collect the same analog signal at the same time. The analog signal provided by the input circuit 1 can be a signal of the monitored device, such as a current signal or a voltage signal of a component in the switch cabinet, or a temperature signal, a humidity signal, etc., which can be set according to actual needs.

The output terminal 33 of the first analog-to-digital conversion circuit 3 is connected to the micro control unit circuit 2. The first analog-to-digital conversion circuit 3 converts the analog signal sent by the input circuit 1 into a digital signal and inputs it into the micro control unit circuit 2. The first analog-to-digital conversion circuit 3 can adopt any type of analog-to-digital conversion circuit in the prior art.

The output terminal 43 of the second analog-to-digital conversion circuit 4 is connected to the micro control unit circuit 2. The second analog-to-digital conversion circuit 4 converts the analog signal sent by the input circuit 1 into a digital signal and inputs it into the micro control unit circuit 2. The second analog-to-digital conversion circuit 4 can adopt any type of analog-to-digital conversion circuit in the prior art.

The microcontroller circuit 2 is used to simultaneously collect the signal of the output terminal 33 of the first analog-to-digital conversion circuit 3 and the signal of the output terminal 43 of the second analog-to-digital conversion circuit 4. If the difference between the two signals exceeds a preset threshold, it can be identified that one of the first analog-to-digital conversion circuit 3 and the second analog-to-digital conversion circuit 4 is faulty. In some cases, other methods can be further used to determine whether the first analog-to-digital conversion circuit 3 or the second analog-to-digital conversion circuit 4 is faulty. For example, if one of the output terminal signals has a full code value and the other has a normal value, the analog-to-digital conversion circuit that has the full code value is the faulty circuit.

According to the monitoring device for a switch cabinet of the utility model, the input ends of the two analog-to-digital conversion circuits are connected to the same input circuit 1, and the output ends of the two analog-to-digital conversion circuits are connected to the same micro-control unit circuit 2. In this way, the micro-control unit circuit 2 can simultaneously collect signals from the output ends of the first analog-to-digital conversion circuit 3 and the second analog-to-digital conversion circuit 4 to identify whether one of the conversion circuits is faulty. The method is simple and has high reliability.

Optionally, the second analog-to-digital conversion circuit 4 has a higher precision than the first analog-to-digital conversion circuit 3, so that the micro-control unit circuit 2 can finally use the signal of the output terminal 43 of the second analog-to-digital conversion circuit 4 for analysis, and perform subsequent operations according to the analysis result. The analog-to-digital conversion circuit with higher precision makes the analysis result of the micro-control unit circuit 2 more accurate.

Optionally, the first analog-to-digital conversion circuit 3 and the microcontroller circuit 2 are integrated on the same chip, and such an analog-to-digital conversion circuit is usually called an on-chip ADC. Such a chip is usually less expensive, but also less accurate, but is sufficient for comparing whether one of the analog-to-digital conversion circuits is faulty.

Optionally, the second analog-to-digital conversion circuit 4 is different from the first analog-to-digital conversion circuit 3 and can be separately arranged on a chip. The accuracy of the separately arranged second analog-to-digital conversion circuit 4 is usually higher than the accuracy of the first analog-to-digital conversion circuit 3 integrated on the same chip as the micro-control unit circuit 2. In this way, the micro-control unit can finally select the signal of the output terminal 43 of the second analog-to-digital conversion circuit 4 for analysis. More specifically, any circuit design in the prior art can be adopted to make the accuracy of the second analog-to-digital conversion circuit 4 higher than that of the first analog-to-digital conversion circuit 3.

Optionally, the second analog-to-digital conversion circuit 4 is connected to the microcontroller circuit 2 via SPI6 (Serial Peripheral Interface). The second analog-to-digital conversion circuit 4 that is separately provided communicates with the microcontroller circuit 2 via SPI6, and has good communication effect, strong anti-interference performance and low cost.

Optionally, the monitoring device for the switch cabinet further includes a first reference signal source 5, which is connected to the reference signal input terminal 32 of the first analog-to-digital conversion circuit 3. The first reference signal source 5 is used to provide a reference signal for the first analog-to-digital conversion circuit 3. The first reference signal source 5 is, for example, a DC power supply, and the reference signal is, for example, a provided reference voltage (reference voltage). The first analog-to-digital conversion circuit 3 outputs a signal based on the reference signal, so that the microprocessing unit circuit 2 can determine the accurate amplitude of the signal at the output terminal of the first analog-to-digital conversion circuit 3. Optionally, as shown in FIG1 , the first reference signal source 5 and the first analog-to-digital conversion circuit 3 are located in different chips, so that the accuracy of the external first reference signal source 5 is usually lower, and the cost is also lower.

Optionally, the second analog-to-digital conversion circuit 4 corresponds to a second reference signal source (not shown in the figure), and the second reference signal source has a higher precision than the first reference signal source 5. The first reference signal source 5 is also connected to the receiving signal terminal 42 of the second analog-to-digital conversion circuit 4, and the receiving signal terminal 42 is used to receive the reference signal provided by the first reference signal source 5, so that the reference signal of the first reference signal source 5 is compared with the reference signal of the second reference signal source to determine the drift degree of the signal of the first reference signal source 5. The operation of determining the drift degree can be directly compared by the second analog-to-digital conversion circuit 4, and the result is output to the micro control unit circuit 2, or the micro control unit circuit 2 compares the reference signal of the first reference signal source 5 and the reference signal of the second reference signal source. After determining the drift degree of the first reference signal source 5, the micro control unit circuit 2 can correct the signal data outputted from the output terminal of the first analog-to-digital conversion circuit 3 to improve its accuracy. This is because the sampling frequency of the first analog-to-digital conversion circuit 3 is high, and the frequency of the output signal is also high, but the accuracy is low. This low accuracy situation may occur when the first analog-to-digital conversion circuit 3 and the micro-control unit circuit 2 are located on the same chip, the first reference signal source 5 corresponding to the first analog-to-digital conversion circuit 2 has low accuracy, or the first reference signal source 5 and the first analog-to-digital conversion circuit 3 are located on different chips. For some situations that require high speed but not too high accuracy, the signal output by the first analog-to-digital conversion circuit 3 can be used for analysis, and its correction does not need to be corrected every time it is sampled, and it can be performed at intervals of a longer period of time.

As shown in FIG1 , the first analog-to-digital conversion circuit 3 and the microcontroller circuit 2 are integrated on the same chip, and the chip where the second analog-to-digital conversion circuit 4 is located is different from the chip where the first analog-to-digital conversion circuit 3 is located. For example, the chip where the second analog-to-digital conversion circuit 4 is located has a second reference signal source, and the chip where the first analog-to-digital conversion circuit 3 is located does not have a reference signal source. Generally, the precision of the built-in reference signal source will be higher, but the price is also higher, and the precision of the external reference signal source will be lower, but the price is also lower.

For example, assuming that the signal at the output terminal 33 of the first analog-to-digital conversion circuit 3 is 5V, and the signal at the output terminal 43 of the second analog-to-digital conversion circuit 4 is 10V, that is, the signal at the output terminal 33 of the first analog-to-digital conversion circuit 3 has a certain drift due to the inaccuracy of the reference signal of the first reference signal source 5. The second analog-to-digital conversion circuit 4 identifies the drift degree of the first reference signal source according to the difference between the data of the first reference signal source 5 and the second reference signal source, and sends it to the micro control unit circuit 2. The drift value of the first analog-to-digital conversion circuit 3 is calculated in the simplest way, and the output voltage value of the first analog-to-digital conversion circuit 3 = [input voltage/(reference voltage provided by the first reference signal source]*full code value. The micro control unit circuit 2 corrects the first analog-to-digital conversion circuit according to the drift voltage sent by the second analog-to-digital conversion circuit 4. In this way, a more accurate output signal can be obtained, and the output voltage value of the second analog-to-digital conversion circuit 3 can be corrected with the same drift voltage for a long period of time, so as to be suitable for the situation with higher speed requirements.

The utility model also includes a switch cabinet, which includes any of the above-mentioned monitoring devices for switch cabinets. The monitoring device for switch cabinets can monitor pressure sensors, temperature sensors, voltage sensors, current sensors, humidity sensors, etc. in the switch cabinet, which can be selected according to actual needs. These sensors can send output signals to the input circuit of the monitoring device for the switch cabinet.

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims (8)

1. Monitoring equipment for cubical switchboard, including input circuit (1), little control unit circuit (2), first analog-to-digital conversion circuit (3), input circuit (1) connect in signal input (31) to be tested of first analog-to-digital conversion circuit (3), output (33) of first analog-to-digital conversion circuit (3) connect in little control unit circuit (2), its characterized in that, monitoring equipment for cubical switchboard still includes:

The input circuit (1) is connected to a tested signal input end (41) of the second analog-to-digital conversion circuit (4), an output end (43) of the second analog-to-digital conversion circuit (4) is connected to the micro control unit circuit (2), and the micro control unit circuit (2) is used for collecting signals of the first analog-to-digital conversion circuit (3) and the second analog-to-digital conversion circuit (4) at the same time.

2. The monitoring device of claim 1, further comprising:

And the first reference signal source (5) is connected with the reference signal input end (32) of the first analog-digital conversion circuit (3).

3. The monitoring device according to claim 2, wherein the second analog-to-digital conversion circuit (4) corresponds to a second reference signal source, the accuracy of which is higher than that of the first reference signal source (5), the first reference signal source (5) being further connected to the receiving signal end (42) of the second analog-to-digital conversion circuit (4).

4. Monitoring device for a switchgear according to claim 2, characterized in that the first reference signal source (5) is located on a different chip than the first analog-to-digital conversion circuit (3).

5. The monitoring device according to claim 1, wherein the first analog-to-digital conversion circuit (3) and the micro control unit circuit (2) are integrated on the same chip, and the chip on which the second analog-to-digital conversion circuit (4) is located is different from the chip on which the first analog-to-digital conversion circuit (3) is located.

6. Monitoring device according to claim 1, characterized in that the second analog-to-digital conversion circuit (4) has a higher accuracy than the first analog-to-digital conversion circuit (3).

7. Monitoring device according to any of claims 1-6, characterized in that the second analog-to-digital conversion circuit (4) is connected to the micro control unit circuit (2) via an SPI (6).

8. A switchgear cabinet comprising a circuit monitoring device according to any of claims 1-7.