CN215932000U - Current detection circuit and electrical equipment - Google Patents

Abstract

The application discloses a current detection circuit and electrical equipment, wherein the circuit comprises a conversion sampling module and a microcontroller which are electrically connected with each other; the conversion sampling module is used for receiving an alternating current signal to be detected, performing signal conversion and sampling on the alternating current signal to be detected, obtaining a sampling voltage signal and outputting the sampling voltage signal to the microcontroller; the microcontroller is used for converting the sampling voltage signal into a current detection result so as to realize the current detection of the alternating current signal to be detected. Compared with the prior detection circuit which detects the sampling voltage after amplifying the sampling voltage through the operational amplifier, the circuit structure is simpler, the accuracy of the circuit detection result and the reliability of the circuit are improved due to the absence of temperature drift, the safety of electrical equipment is ensured, and the service lives of electronic components and electrical equipment are prolonged.

Description

Current detection circuit and electrical equipment

Technical Field

The application relates to the technical field of electronic circuits, in particular to a current detection circuit and electrical equipment.

Background

The electric equipment is a general name of appliances which can work only by being electrified, generally, the household electric equipment supplies power through an urban power distribution network, in China, the urban power distribution network directly faces to vast power consumers, the power supply mode can be summarized into a high-voltage receiving-transformer step-down-low-voltage distribution mode, and generally, high-voltage electricity of a power plant is converted into 220V commercial power to be supplied to the power consumers after being subjected to step-down conversion by a transformer substation.

Due to the development of the technology, more and more electrical equipment is used in power consumers, correspondingly, parameter values of power, current and the like in a power supply loop are larger and larger, if the current in the power supply loop exceeds a safe range which can be borne by the electrical equipment, potential safety hazards exist to cause the electrical equipment to break down or be damaged, and therefore, in order to ensure that the current flowing through the electrical equipment is within the safe range, the current can be detected. At present, alternating current flowing through electrical equipment is commonly detected at a strong current input end of the electrical equipment, under a common condition, current is sampled by a precision resistor with a small resistance value, the current flowing through a loop can generate sampling voltage with a small voltage value at two ends of the precision resistor, the sampling voltage is amplified by an operational amplifier and then processed into a direct current voltage signal which can be identified by a main control chip, and current detection is further realized.

However, in the prior art, the operational amplifier is used for amplifying the sampling voltage, the operational amplifier has large temperature drift, and the amplification factors of the operational amplifier at different temperatures have differences, so that the measurement data deviation is easily large, and the accuracy of the detection result is low.

SUMMERY OF THE UTILITY MODEL

The application provides a current detection circuit and electrical equipment, when aiming at solving and enlargiing sampling voltage through operational amplifier among the prior art, because operational amplifier has great temperature drift, lead to the measured data deviation great easily, the lower problem of testing result degree of accuracy.

In a first aspect, the present application provides a current detection circuit, including a conversion sampling module and a microcontroller electrically connected to each other;

the conversion sampling module is used for receiving the alternating current signal to be detected, performing signal conversion and sampling on the alternating current signal to be detected, obtaining a sampling voltage signal and outputting the sampling voltage signal to the microcontroller;

and the microcontroller is used for converting the sampling voltage signal into a current detection result so as to realize the current detection of the alternating current signal to be detected.

In one possible implementation manner of the present application, the conversion sampling module includes a current conversion module and a voltage division sampling module electrically connected, and the voltage division sampling module is electrically connected to the microcontroller;

the current conversion module is used for receiving an alternating current signal to be detected, converting the alternating current signal to be detected into an alternating voltage signal and outputting the alternating voltage signal to the partial pressure sampling module;

and the voltage division sampling module is used for converting the alternating voltage signal into a direct voltage signal, sampling the direct voltage signal and outputting the sampled voltage signal to the microcontroller.

In one possible implementation manner of the present application, the voltage division sampling module includes a rectifier device and a voltage division module electrically connected to each other, the rectifier device is electrically connected to the current conversion module, and the voltage division module is electrically connected to the microcontroller;

the rectifier device is used for converting the alternating voltage signal into a direct voltage signal and outputting the direct voltage signal to the voltage division module;

and the voltage division module is used for dividing and sampling the direct-current voltage signal to obtain a sampling voltage signal and outputting the sampling voltage signal to the microcontroller.

In one possible implementation manner of the present application, the rectifier device is a rectifier diode, the voltage dividing module includes a second resistor and a third resistor, an anode of the rectifier diode is connected to an output terminal of the current converting module, a cathode of the rectifier diode is connected to one end of the second resistor, the other end of the second resistor is connected to one end of the microcontroller and one end of the third resistor, and the other end of the third resistor is grounded.

In one possible implementation manner of the present application, the current detection circuit further includes a voltage protection device electrically connected to the voltage division sampling module and the microcontroller, respectively;

and the voltage protection device is used for comparing the sampling voltage signal with a preset reference voltage to obtain a comparison result, and selectively outputting one of the sampling voltage signal or the preset reference voltage to the microcontroller according to the comparison result.

In one possible implementation manner of the present application, the voltage protection device is configured with two device states, namely, a conducting state and a disconnecting state, and the voltage protection device is configured to output a sampling voltage signal to the microcontroller in the disconnecting state and output a preset reference voltage to the microcontroller in the conducting state.

In one possible implementation manner of the present application, the comparison result includes a first comparison result and a second comparison result, the first comparison result represents that the sampled voltage signal is less than or equal to the preset reference voltage, and the second comparison result represents that the sampled voltage signal is greater than the preset reference voltage;

when the comparison result is a first comparison result, the voltage protection device is in a disconnected state to output a sampling voltage signal to the microcontroller;

and when the comparison result is a second comparison result, the voltage protection device is in a disconnected state so as to output the preset reference voltage to the microcontroller.

In one possible implementation of the present application, the voltage protection device is a clamping diode.

In this application, current detection circuit still includes the filter module who connects between partial pressure sampling module and microcontroller, and the filter module includes electrolytic capacitor and filter circuit, and electrolytic capacitor's positive pole is connected with partial pressure sampling module's output and filter circuit's input respectively, and electrolytic capacitor's negative pole ground connection, filter circuit's output and microcontroller are connected.

In a possible implementation manner of the present application, the current conversion module includes a current transformer and a first resistor connected in parallel, the current transformer is configured to receive an alternating current signal to be detected, convert the alternating current signal to be detected into a first alternating current, and output the first alternating current to the first resistor, and the first resistor is configured to convert the first alternating current into an alternating voltage signal and output the alternating voltage signal to the voltage division sampling module.

In a second aspect, the present application further provides an electrical device, in which the current detection circuit of the first aspect is integrated.

In one possible implementation manner of the present application, the electrical device is an air conditioner.

1. In this application, treat through conversion sampling module and detect alternating current signal and carry out signal conversion and sampling, obtain sampling voltage signal output to microcontroller, convert sampling voltage signal into corresponding current detection result through microcontroller, alright in order to realize the detection to alternating current, compare in present detection circuit through operational amplifier again after amplifying sampling voltage detect, circuit structure is simpler, and because there is not temperature drift, the circuit detection result's accuracy and circuit reliability have been improved, electrical equipment's security has been ensured, the life of extension electronic components and electrical equipment.

2. In this application, will wait to detect alternating current signal conversion and be alternating voltage signal through the current conversion module, then convert alternating voltage signal into direct voltage signal through partial pressure sampling module, and sample the direct voltage signal after the conversion and obtain the sampling voltage signal, convert sampling voltage signal into corresponding current detection result through microcontroller, alright in order to realize the detection to alternating current, compare in present detection circuit again detect after amplifying sampling voltage through operational amplifier, requirement to electronic components is lower, circuit structure is simpler, and owing to there is not temperature drift, the precision and the circuit reliability of circuit detection result have been improved, the security of electrical equipment has been ensured, the life of extension electronic components and electrical equipment.

3. In this application, carry out the partial pressure sampling to DC voltage signal through second resistance and third resistance, compare and adopt accurate resistance to sample the electric current in current detection circuitry, lower to the requirement of resistance, practiced thrift the detection cost.

4. In this application, compare sampling voltage signal and preset reference voltage through protection module, when sampling voltage signal is greater than preset reference voltage, through being in the protection module of on-state will predetermine reference voltage and export to microcontroller, rather than exporting sampling voltage signal to microcontroller, can avoid being greater than sampling voltage signal of predetermineeing reference voltage to cause the impact to microcontroller and make its damage, the voltage of having guaranteed to input to microcontroller is no longer than predetermineeing reference voltage, in order to carry out voltage protection to microcontroller, microcontroller's life has further been prolonged.

5. In this application, carry out filtering process to the sampled voltage signal through the filtering module, utilize the characteristic of electric capacity, filter the alternating current composition that is mingled with in the sampled voltage signal through electrolytic capacitor for the sampled voltage signal waveform is level and smooth, and filter the high frequency alternating current composition in the sampled voltage signal through filter circuit, further improved the accurate nature of circuit testing result.

Drawings

In order to more clearly illustrate the technical solutions in the present application, the drawings that are needed to be used in the description of the present application will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without inventive effort.

Fig. 1 is a schematic structural diagram of a current detection circuit provided in an embodiment of the present application;

FIG. 2 is a schematic circuit diagram of a current sensing circuit provided in an embodiment of the present application;

fig. 3 is a schematic structural diagram of an electrical apparatus provided in an embodiment of the present application.

Detailed Description

The technical solutions in the present application will be described clearly and completely with reference to the accompanying drawings in the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In the description of the present application, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed in a particular orientation, and be operated, and thus should not be considered as limiting the present application. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

In this application, the word "exemplary" is used to mean "serving as an example, instance, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. The following description is presented to enable any person skilled in the art to make and use the application. In the following description, details are set forth for the purpose of explanation. It will be apparent to one of ordinary skill in the art that the present application may be practiced without these specific details. In other instances, well-known structures and processes are not set forth in detail in order to avoid obscuring the description of the present application with unnecessary detail. Thus, the present application is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.

Next, the current detection circuit and the electric device provided in the present application will be described in detail.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a current detection circuit provided in an embodiment of the present application. The current detection circuit can comprise a conversion sampling module 100 and a microcontroller 105 which are electrically connected with each other, wherein the conversion sampling module 100 can be used for receiving an alternating current signal to be detected, performing signal conversion and sampling on the alternating current signal to be detected, and outputting a sampling voltage signal to the microcontroller 105; the microcontroller 105 may be configured to convert the sampled voltage signal into a current detection result to implement current detection of the ac current signal to be detected.

In the embodiment of the application, treat through conversion sampling module 100 and detect alternating current signal and carry out signal conversion and sampling, obtain sampling voltage signal output to microcontroller 105, rethread microcontroller 105 converts sampling voltage signal into corresponding current detection result, alright in order to realize the detection to alternating current, compare in present detection circuit in through operational amplifier amplify sampling voltage again after detect, circuit structure is simpler, and because there is not temperature drift, the accuracy and the circuit reliability of circuit detection result have been improved, electrical equipment's security has been ensured, extension electronic components and electrical equipment's life.

As shown in fig. 1, in some embodiments of the present application, the conversion sampling module 100 may include a current conversion module 101 and a voltage division sampling module 102 electrically connected, and the voltage division sampling module 102 is electrically connected to a microcontroller 105; the current conversion module 101 may be configured to receive an alternating current signal to be detected, convert the alternating current signal to be detected into an alternating voltage signal, and output the alternating voltage signal to the voltage division sampling module 102; the voltage division and sampling module 102 may be configured to convert the ac voltage signal into a dc voltage signal, sample the dc voltage signal, obtain a sampled voltage signal, and output the sampled voltage signal to the microcontroller 105.

In the embodiment of the present application, the ac current signal to be detected received by the current conversion module 101 may be an ac current flowing into an electrical apparatus provided by a commercial power in a power supply network, or an ac current flowing through an electrical apparatus in a power loop of a power consumer, since the power consumers use various electric devices in their homes in different starting situations, the value of the ac current flowing into the electric devices also varies, and in general, the more electrical equipment which works and operates simultaneously, the larger the value of the alternating current is, therefore, in order to avoid the larger alternating current from causing impact on the electrical equipment to cause the fault or damage of the electrical equipment, in the embodiment of the application, the current conversion module 101 can convert the incoming ac current signal to be detected into a corresponding ac voltage signal, and outputs the ac voltage signal to the voltage division sampling module 102, so that the subsequent circuit can detect the ac voltage signal.

In the embodiment of the present application, the alternating current signal to be detected is converted into an alternating voltage signal by the current conversion module 101, then the voltage division sampling module 102 converts the alternating current voltage signal into a direct current voltage signal, samples the converted direct current voltage signal to obtain a sampling voltage signal, the sampling voltage signal is converted into a corresponding current detection result by the microcontroller 105, so that the detection of the alternating current can be realized, compared with the detection after the sampling voltage signal is amplified by an operational amplifier in the existing detection circuit, the requirements on electronic components are lower, the circuit structure is simpler, and the accuracy of the circuit detection result and the circuit reliability are improved due to no temperature drift, the accuracy of the current detection result can be ensured, the safety of electrical equipment is ensured, and the service lives of electronic components and the electrical equipment are prolonged.

Referring to fig. 2, fig. 2 is a schematic circuit diagram of a current detection circuit provided in an embodiment of the present application, in some embodiments of the present application, a current conversion module 101 may include a current transformer L and a first resistor R1 connected in parallel, where the current transformer L may be configured to receive an ac current signal to be detected, convert the ac current signal to be detected into a first ac current, and output the first ac current to the first resistor R1, and the first resistor R1 may be configured to convert the first ac current into an ac voltage signal and output the ac voltage signal to a voltage division sampling module 102.

Specifically, the current transformer is an instrument for converting a large primary side current into a small secondary side current according to the electromagnetic induction principle to measure, and generally, the current transformer is composed of a closed iron core and a winding, the primary side winding has a small number of turns and is connected in series in a circuit of a current to be measured, and the secondary side winding has a large number of turns and is connected in series in a measuring circuit. In the embodiment of the present application, the current transformer L is equivalent to a linear transformer, a primary side of the linear transformer may be connected in series to a mains line, and a secondary side of the linear transformer is connected in series to the current detection circuit shown in fig. 2, wherein an input current at the primary side, that is, an alternating current signal to be detected, and an output current at the secondary side, that is, a first alternating current, are in a proportional relationship with the number of turns of an internal coil of the current transformer L, and assuming that the input current at the primary side is Ii and the turn ratio of a primary side coil and a secondary side coil of the current transformer L is a constant C, a calculation formula of the first alternating current output by the current transformer L may be represented as Io — Ii/C.

In this embodiment of the application, the first resistor R1 may be used to simulate a load resistor, which is equivalent to provide a bias resistor for magnetic field conversion of the current transformer L, so as to ensure that a conversion magnetic field inside the current transformer L is always in a non-saturated state, so that the current transformer L converts an ac current signal to be detected into a first ac current; the resistance of the first resistor R1 may be much smaller than the value of the voltage division sampling module 102, so that the first resistor R1 may be equivalent to an actual load resistor, and the voltage across the first resistor R1 may be obtained according to the above-mentioned calculation formula Io ═ Ii/C of the first alternating current, that is, the alternating voltage signal obtained by converting the first alternating current by the first resistor R1 is obtained, and therefore, the calculation formula of the alternating voltage signal may be represented as Uo ═ R1 ═ Io ═ R1 ═ Ii/C.

Referring to fig. 1, in some embodiments of the present application, the voltage division sampling module 102 may include a rectifying device 1021 and a voltage division module 1022 electrically connected to each other, wherein the rectifying device 1021 is electrically connected to the current conversion module 101, and the voltage division module 1022 is electrically connected to the microcontroller 105; the rectifying device 1021 may be configured to convert the ac voltage signal into a dc voltage signal, and output the dc voltage signal to the voltage dividing module 1022; the voltage dividing module 1022 may be configured to divide and sample the dc voltage signal, obtain a sampled voltage signal, and output the sampled voltage signal to the microcontroller 105. Specifically, the rectifying device 1021 may be any device having a rectifying function, such as a rectifying diode, a rectifying bridge, a rectifier, and the like; the voltage dividing module 1022 may be a device capable of sampling a dc voltage signal, such as a common precision resistor or a common voltage dividing resistor.

As shown in fig. 2, in the embodiment of the present application, the rectifying device 1021 is a rectifying diode D1 capable of performing half-wave rectification on an ac voltage signal, and the voltage dividing module 1022 may include a second resistor R2 and a third resistor R3 connected in series, and compared with sampling a current with a precision resistor, the requirement for the resistors by using the second resistor R2 and the third resistor R3 connected in series is lower, so that detection cost may be saved, where an anode of the rectifying diode D1 is connected to an output terminal of the current converting module 101, that is, as shown in fig. 2, an anode of the rectifying diode D1 is connected to a non-ground terminal of the current transformer L, a cathode of the rectifying diode D1 is connected to one end of the second resistor R2, another end of the second resistor R2 is connected to one end of the third resistor R3 and a Microcontroller (MCU) 105, and another end of the third resistor R3 is grounded. After the ac voltage signal is half-wave rectified into the dc voltage signal by the rectifier diode D1, the voltage between the cathode of the rectifier diode D1 and the ground, i.e., the dc voltage signal output by the rectifier diode D1, can be calculated as:

V1＝1.414/2*Uo＝0.707*R1*Ii/C-e

wherein e is used to represent the voltage drop of the rectifier diode D1, and usually the voltage drop of the rectifier diode D1 is about 0.5v, so in this embodiment, e may take a value of 0.5, where the value of e is only an example of this embodiment, for different application scenarios, the adopted rectifier diode D1 is different, and the value of e is also different, so e may also take other values, and specifically may be determined according to the selected rectifier diode D1, and in addition, in some application scenarios with low precision requirements, the voltage drop of the rectifier diode D1 may also be ignored, and therefore, e may also take a value of 0.

After the dc voltage signal V1 flows to the voltage dividing module 1022, the voltage at the two ends of the third resistor R3 can be obtained by dividing the voltage by the second resistor R2 and the third resistor R3, and at this time, the voltage at the two ends of the third resistor R3 is the sampling voltage signal, so the calculation formula of the sampling voltage signal can be represented as:

V2＝R3/(R2+R3)*V1＝R3/(R2+R3)*(0.707*R1*Ii/C-e)。

in addition, as shown in fig. 1, in some embodiments of the present application, the current detection circuit may further include a voltage protection device 104 electrically connected to the voltage division sampling module 102 and the microcontroller 105, respectively, and the voltage protection device 104 may be configured to compare the sampled voltage signal with a preset reference voltage to obtain a comparison result, and selectively output one of the sampled voltage signal and the preset reference voltage to the microcontroller 105 according to the comparison result. Specifically, in the embodiment of the present application, in order to avoid that the sampling voltage signal input to the microcontroller 105 is too high and damages the microcontroller 105, the voltage protection device 104 may perform voltage protection on the microcontroller 105, the voltage protection device 104 may be set with a preset reference voltage, the preset reference voltage may be set as a rated working voltage of the microcontroller 105, or may be set as a highest voltage that the microcontroller 105 can bear, the voltage protection device 104 obtains a comparison result by comparing the sampling voltage signal with the preset reference voltage, and may select the voltage input to the microcontroller 105 according to the comparison result.

In this embodiment, the voltage protection device 104 may be configured with two device states, i.e., an on state and an off state, and the voltage protection device 104 may output a sampling voltage signal to the microcontroller 105 in the off state and output a preset reference voltage to the microcontroller 105 in the on state. Specifically, in this embodiment, the comparison result may include a first comparison result and a second comparison result, where the first comparison result may be used to indicate that the sampled voltage signal is less than or equal to the preset reference voltage, and the second comparison result may be used to indicate that the sampled voltage signal is greater than the preset reference voltage; when the comparison result is the first comparison result, the voltage protection device 104 may be in an off state, and at this time, the voltage protection device 104 may output a sampling voltage signal to the microcontroller 105; when the comparison result is the second comparison result, the voltage protection device 104 may operate in an off state, and at this time, the voltage protection device 104 may output the preset reference voltage to the microcontroller 105.

Specifically, in some embodiments of the present application, the voltage protection device 104 is a clamping diode, the clamping diode is a diode that limits a potential at a certain point in the circuit, in a specific application, a potential connected to one end of the clamping diode should be a constant voltage, that is, a potential at the end does not change, and is used as a reference potential, while the other end is a clamped end, a potential at the end can change, that is, the end is a end that needs to be limited, and a potential at the clamped end is forcibly pulled to the reference end by a clamping action of the diode, that is, clamping. As shown in fig. 2, in the present embodiment, the voltage protection device 104 is a clamping diode D2, an anode of the clamping diode D2 is connected to a PA1 port of the MCU, the PA1 port may be an Analog-to-Digital (AD) sampling port of the MCU, a cathode of the clamping diode D2 is connected to a +5V reference voltage, where the +5V reference voltage is a preset reference voltage, and an anode of the clamping diode D2 is a clamped terminal. When the voltage at the two ends of the third resistor R3, that is, the value of the sampling voltage signal V2, is less than or equal to +5V, the sampling voltage signal may be considered to be less than or equal to a preset reference voltage, at this time, the clamping diode D2 is turned off, that is, is in an off state, and the sampling voltage signal is input to the MCU through the PA1 port; when the voltage at the two ends of the third resistor R3, that is, the value of the sampling voltage signal V2, is greater than +5V, it may be considered that the sampling voltage signal is greater than the preset reference voltage, at this time, the anode voltage of the clamp diode D2 is higher than the cathode voltage, the clamp diode D2 is turned on, that is, in a conducting state, if the voltage drop of the clamp diode D2 itself is ignored, the conducting clamp diode D2 is equivalent to a conducting wire, at this time, the potential of the anode of the clamp diode D2 is the +5V reference voltage, and therefore, at this time, the sampling voltage signal is clamped as the preset reference voltage and is input to the MCU through the PA1 port; after the sampled voltage signal is input to the microcontroller 105, the microcontroller 105 may call a pre-stored mapping table of the sampled voltage signal and the current parameter, and search the current parameter matched with the received sampled voltage signal in the mapping table, where the current parameter is the current detection result.

In the embodiment of the present application, the protection module 104 compares the sampling voltage signal with the preset reference voltage, when the sampling voltage signal is greater than the preset reference voltage, the protection module 104 in the on state outputs the preset reference voltage to the microcontroller 105 instead of outputting the sampling voltage signal to the microcontroller 105, so that the sampling voltage signal greater than the preset reference voltage can be prevented from causing impact to the microcontroller 105 to damage the microcontroller 105, it is ensured that the voltage input to the microcontroller 105 does not exceed the preset reference voltage, so as to perform voltage protection on the microcontroller 105, the service life of the microcontroller 105 is further prolonged, and the working reliability of the microcontroller 105 is ensured.

In addition, in this application embodiment, can also carry out voltage protection to microcontroller 105 through the relay, it is concrete, the relay can adopt normally open relay, this normally open relay can connect preset reference voltage equally, when sampling voltage signal is less than or equal to preset reference voltage, normally open relay's normally open contact is in the off-state, normally open relay does not insert the return circuit promptly, when sampling voltage signal is greater than preset reference voltage, can control normally open relay's normally open contact closure, this moment, normally open relay inserts the return circuit and can pull into microcontroller 105's voltage into preset reference voltage equally, thereby realize the voltage protection to microcontroller 105.

As shown in fig. 1, in some embodiments of the present application, the current detection circuit may further include a filtering module 103 connected between the voltage division sampling module 102 and the microcontroller 105, the filtering module 103 includes an electrolytic capacitor 1031 and a filtering circuit 1032, an anode of the electrolytic capacitor 1031 is connected to an output terminal of the voltage division sampling module 102 and an input terminal of the filtering circuit 1032, a cathode of the electrolytic capacitor 1031 is grounded, and an output terminal of the filtering circuit 1032 is connected to the microcontroller 105. Specifically, as shown in fig. 2, the anode of the electrolytic capacitor E is connected to the junction of the second resistor R2 and the third resistor R3, the cathode of the electrolytic capacitor E is grounded, the filter circuit 1032 includes a fourth resistor R4 and a capacitor C connected in series, and the two ends of the fourth resistor R4 and the capacitor C which are connected in series are connected in parallel with the electrolytic capacitor E, the anode of the electrolytic capacitor E is connected with the fourth resistor R4, one end of the capacitor C is grounded, the connection part of the fourth resistor R4 and the capacitor C is connected with the PA1 port of the MCU, filtering the AC component mixed in the sampled voltage signal by the electrolytic capacitor E to smooth the waveform of the sampled voltage signal, the high-frequency alternating current component in the sampling voltage signal is filtered through the RC filter circuit formed by the fourth resistor R4 and the capacitor C, so that high-frequency interference can be prevented, and the accuracy of a circuit detection result is further improved; meanwhile, the capacitor C can also be used for supplementing the electric quantity consumed by the PA1 port of the MCU, so that the sampling voltage signal is prevented from dropping, and the sampling precision is further ensured.

Fig. 3 is a schematic structural diagram of an electrical apparatus provided in the embodiment of the present application. On the basis of the foregoing embodiments, the present application further provides an electrical device 300, where the electrical device 300 is integrated with any one of the current detection circuits in the foregoing embodiments, and in some embodiments, the electrical device may be an air conditioner or other household appliance. Specifically, electrical equipment 300 can connect the commercial power, microcontroller 105 can connect working devices such as electrical equipment's compressor or motor, after microcontroller 105 obtained the current detection result through the sampling voltage signal, can control electrical equipment's working device's operation according to this current detection result, and when microcontroller 105 received preset reference voltage, can think that the sampling voltage signal is greater than preset reference voltage, at this moment, microcontroller 105 can control electrical equipment and stop operating, thereby ensure electrical equipment's security, improve the reliability that electrical equipment used.

In the above embodiments, the descriptions of the respective embodiments have respective emphasis, and parts that are not described in detail in a certain embodiment may refer to the above detailed descriptions of other embodiments, and are not described herein again.

In a specific implementation, each unit or structure may be implemented as an independent entity, or may be combined arbitrarily to be implemented as one or several entities, and the specific implementation of each unit or structure may refer to the foregoing embodiments, which are not described herein again.

The above detailed description is made on the current detection circuit and the electrical equipment provided by the present application, and a specific example is applied in the present application to explain the principle and the implementation of the present application, and the above description is only used to help understand the circuit and the core idea of the present application; meanwhile, for those skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present application.

Claims (10)

1. A current detection circuit is characterized by comprising a conversion sampling module and a microcontroller which are electrically connected with each other;

the conversion sampling module is used for receiving an alternating current signal to be detected, performing signal conversion and sampling on the alternating current signal to be detected, obtaining a sampling voltage signal and outputting the sampling voltage signal to the microcontroller;

and the microcontroller is used for converting the sampling voltage signal into a current detection result so as to realize the current detection of the alternating current signal to be detected.

2. The current detection circuit of claim 1, wherein the conversion sampling module comprises a current conversion module and a voltage division sampling module electrically connected, and the voltage division sampling module is electrically connected with the microcontroller;

the current conversion module is used for receiving the alternating current signal to be detected, converting the alternating current signal to be detected into an alternating voltage signal and outputting the alternating voltage signal to the partial pressure sampling module;

the voltage division sampling module is used for converting the alternating voltage signal into a direct voltage signal, sampling the direct voltage signal, and outputting the obtained sampling voltage signal to the microcontroller.

3. The current detection circuit according to claim 2, wherein the voltage division sampling module comprises a rectifying device and a voltage division module electrically connected to each other, the rectifying device is electrically connected to the current conversion module, and the voltage division module is electrically connected to the microcontroller;

the rectifier device is used for converting the alternating voltage signal into the direct voltage signal and outputting the direct voltage signal to the voltage dividing module;

and the voltage division module is used for dividing and sampling the direct-current voltage signal to obtain a sampling voltage signal and outputting the sampling voltage signal to the microcontroller.

4. The current detection circuit according to claim 3, wherein the rectifying device is a rectifying diode, the voltage division module includes a second resistor and a third resistor, an anode of the rectifying diode is connected to the output terminal of the current conversion module, a cathode of the rectifying diode is connected to one end of the second resistor, the other end of the second resistor is connected to one end of the microcontroller and the third resistor, and the other end of the third resistor is grounded.

5. The current detection circuit according to claim 2, further comprising a voltage protection device electrically connected to the divided voltage sampling module and the microcontroller, respectively;

the voltage protection device is used for comparing the sampling voltage signal with a preset reference voltage to obtain a comparison result, and selectively outputting one of the sampling voltage signal or the preset reference voltage to the microcontroller according to the comparison result.

6. The current sensing circuit of claim 5, wherein the voltage protection device is configured with two device states, an on state and an off state, and wherein the voltage protection device is configured to output the sampled voltage signal to the microcontroller in the off state and output the predetermined reference voltage to the microcontroller in the on state.

7. The current sensing circuit of claim 6, wherein the comparison results comprise a first comparison result and a second comparison result, the first comparison result indicating that the sampled voltage signal is less than or equal to the preset reference voltage, the second comparison result indicating that the sampled voltage signal is greater than the preset reference voltage;

when the comparison result is the first comparison result, the voltage protection device is in the off state to output the sampling voltage signal to the microcontroller;

and when the comparison result is the second comparison result, the voltage protection device is in the off state to output the preset reference voltage to the microcontroller.

8. The current detection circuit according to claim 2, further comprising a filter module connected between the voltage division sampling module and the microcontroller, wherein the filter module comprises an electrolytic capacitor and a filter circuit, an anode of the electrolytic capacitor is connected to an output terminal of the voltage division sampling module and an input terminal of the filter circuit, respectively, a cathode of the electrolytic capacitor is grounded, and an output terminal of the filter circuit is connected to the microcontroller.

9. The current detection circuit according to claim 2, wherein the current conversion module includes a current transformer and a first resistor connected in parallel, the current transformer is configured to receive the ac current signal to be detected, convert the ac current signal to be detected into a first ac current, and output the first ac current to the first resistor, and the first resistor is configured to convert the first ac current into the ac voltage signal and output the ac voltage signal to the voltage division and sampling module.

10. An electrical apparatus, characterized in that the current detection circuit according to any one of claims 1-9 is integrated in the electrical apparatus.

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