CN117439606B - AD isolation sampling circuit for power carrier communication and multi-split air conditioning system - Google Patents
AD isolation sampling circuit for power carrier communication and multi-split air conditioning system Download PDFInfo
- Publication number
- CN117439606B CN117439606B CN202311728413.7A CN202311728413A CN117439606B CN 117439606 B CN117439606 B CN 117439606B CN 202311728413 A CN202311728413 A CN 202311728413A CN 117439606 B CN117439606 B CN 117439606B
- Authority
- CN
- China
- Prior art keywords
- resistor
- capacitor
- sampling
- module
- pin
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000005070 sampling Methods 0.000 title claims abstract description 135
- 238000004891 communication Methods 0.000 title claims abstract description 50
- 238000002955 isolation Methods 0.000 title claims abstract description 32
- 238000004378 air conditioning Methods 0.000 title claims abstract description 28
- 238000006243 chemical reaction Methods 0.000 claims abstract description 89
- 239000003990 capacitor Substances 0.000 claims description 120
- 238000010586 diagram Methods 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M1/00—Analogue/digital conversion; Digital/analogue conversion
- H03M1/12—Analogue/digital converters
- H03M1/124—Sampling or signal conditioning arrangements specially adapted for A/D converters
- H03M1/1245—Details of sampling arrangements or methods
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
- G06F3/05—Digital input using the sampling of an analogue quantity at regular intervals of time, input from a/d converter or output to d/a converter
Landscapes
- Engineering & Computer Science (AREA)
- Theoretical Computer Science (AREA)
- Human Computer Interaction (AREA)
- Physics & Mathematics (AREA)
- General Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Measurement Of Current Or Voltage (AREA)
Abstract
The invention discloses an AD isolation sampling circuit for power carrier communication and a multi-split air conditioning system, comprising: the bias voltage module is used for connecting with the amplifying module; the amplifying module is internally provided with a first sampling resistor; the first comparator module is provided with a first preset voltage; the amplifying module is used for connecting the amplifying module; and the isolator module is used for being connected with the first comparator module. According to the invention, the first sampling voltage amplified by the amplifying module is compared with the first preset voltage through the first comparator module, the comparison result is subjected to analog-to-digital conversion to generate the first conversion signal, the digitized first conversion signal can stably flow to the main control MCU through the isolator module, and the main control MCU judges whether leakage current exists or not according to the high/low level of the first conversion signal, so that AD sampling isolation of power carrier communication is realized, the accuracy of circuit sampling is improved, and the cost is reduced.
Description
Technical Field
The invention relates to the technical field of electronic circuits, in particular to an AD isolation sampling circuit for power carrier communication and a multi-split air conditioning system.
Background
The multi-split air conditioning system refers to that a plurality of air conditioning indoor units are mutually cascaded, and only one air conditioning indoor unit supplies power to a wire controller. In the multi-split air conditioning system, as the multi-split air conditioning system is directly fluidized, the ground wire on the main board is connected with the commercial power, the voltage is provided, and the power carrier communication is an external wiring, so that the safety isolation is needed, and the power isolation can be solved by adopting the transformer winding isolation.
In the current power carrier communication power supply system, resistor sampling is mainly adopted to realize overcurrent protection of the power supply system and leakage protection of cascade connection of multiple air conditioners. However, in the practical use process, in order to realize larger power output of the power supply, the resistance value of the sampling resistor is very small, so the sampling voltage value is small, and because the set current threshold value of the leakage current is small, the sampling voltage value is very small, so that the digitization of the sampling voltage value is difficult, the sampling accuracy is further affected, and therefore, whether current leakage exists in the power supply carrier communication power supply system is difficult to judge.
Disclosure of Invention
In view of the above, the invention provides an AD isolation sampling circuit for power carrier communication and a multi-split air conditioning system, which are used for solving the problems that in the prior art, the voltage value sampled by the resistor of a power carrier communication power supply system is difficult to digitize, and the sampling accuracy is affected.
To achieve one or a part or all of the above or other objects, the technical solution of the present invention is an AD isolation sampling circuit for power carrier communication, including:
the bias voltage module is used for being connected with the amplifying module and providing bias voltage for the amplifying module;
an amplifying module containing a first sampling resistor; amplifying a first sampling voltage of the first sampling resistor;
a first comparator module provided with a first preset voltage; the amplifying module is used for connecting the amplified first sampling voltage with the first preset voltage, comparing the amplified first sampling voltage with the first preset voltage and performing analog-digital conversion to generate a first conversion signal;
and the isolator module is used for being connected with the first comparator module, isolating the first conversion signal output by the first comparator module and stably conveying the first conversion signal to the main control MCU.
Further, still include:
the overcurrent protection module comprises a second sampling resistor and a second comparator module;
the second comparator module is provided with a second preset voltage; and the isolator module is used for connecting the isolator module, comparing a second sampling voltage of a second sampling resistor with the second preset voltage and performing analog-digital conversion to generate a second conversion signal.
Further, the amplifying module comprises a first sampling resistor R1, a resistor R14, a resistor R15, a resistor R16, a resistor R17, a resistor R18, a capacitor C5, a capacitor C6, a capacitor C7 and an operational amplifier U2;
the first end of the first sampling resistor R1 is connected with the first end of the resistor R16, the second end of the resistor R15 and the negative electrode of the capacitor C5 are simultaneously connected with the same-phase end of the operational amplifier U2, and the first end of the resistor R15 and the positive electrode of the capacitor C5 are simultaneously connected with the output end of the bias voltage module;
the inverting terminal of the operational amplifier U2 is connected with the first terminal of the resistor R14, the first terminal of the resistor R17 and the anode of the capacitor C6 at the same time; the output end of the operational amplifier U2 is connected with the second end of the resistor R17, the first end of the resistor R18 and the negative electrode of the capacitor C6 at the same time; the second end of the resistor R18 and the positive electrode of the capacitor C7 are simultaneously connected with the input end of the first comparator module; the second end of the first sampling resistor R1, the second end of the resistor R14 and the negative electrode of the capacitor C7 are simultaneously connected to the ground pin AGND.
Further, the first sampling voltage amplified by the amplifying module is V1, and the calculation formula of V1 is:
V1=Va+(R15/R16)*V_ADC1；
V_ADC1=R1*I1；
wherein Va is the bias voltage provided by the bias voltage module, R15 is the resistance of the resistor R15, R16 is the resistance of the resistor R16, v_adc1 is the first sampling voltage, R1 is the resistance of the first sampling resistor R1, and I1 is the current of the first sampling resistor R1.
Further, the bias voltage module comprises a resistor R12, a resistor R13, a capacitor C3, a capacitor C4 and an operational amplifier U1;
the same-phase end of the operational amplifier U1 is connected with the first end of the resistor R12, the first end of the resistor R13 and the anode of the capacitor C3 at the same time; the inverting terminal of the operational amplifier U1, the output terminal of the operational amplifier U1 and the positive electrode of the capacitor C4 are simultaneously connected with the first terminal of the resistor R15; the second end of the resistor R12 is connected with a 3.3V pin; the second end of the resistor R13, the negative electrode of the capacitor C3 and the negative electrode of the capacitor C4 are simultaneously connected with the ground pin AGND.
Further, the first comparator module comprises a resistor R19, a resistor R20, a resistor R21, a capacitor C8, a capacitor C9 and an operational amplifier U3;
the non-inverting terminal of the operational amplifier U3 is used as the input terminal of the comparator module, the inverting terminal of the operational amplifier U3 is simultaneously connected with the first terminal of the resistor R19, the first terminal of the resistor R20 and the positive electrode of the capacitor C8, and the power supply terminal of the operational amplifier U3, the second terminal of the resistor R19, the second terminal of the resistor R21, the positive electrode of the capacitor C9 and the first input terminal of the isolator module are simultaneously connected with a 3.3V pin; the output end of the operational amplifier U3 and the first end of the resistor R21 are simultaneously connected with the second input end of the isolator module; the ground supply end of the operational amplifier U3, the second end of the resistor R20, the negative electrode of the capacitor C8 and the negative electrode of the capacitor C9 are simultaneously connected to the ground pin AGND.
Further, the first preset voltage of the first comparator module is V2, and a calculation formula of V2 is:
V2=R20/(R20+R19)*Vb；
wherein R19 is the resistance of the resistor R19, R20 is the resistance of the resistor R20, and Vb is the voltage of the 3.3V pin.
Further, the isolator module comprises an isolator U5;
the high-voltage power supply is characterized in that a 3.3V pin is connected to a 1 pin of the isolator U5, a ground pin AGND is connected to a 2 pin and a 8 pin of the isolator U5, a 3 pin of the isolator U5 is connected with an output end of the operational amplifier U3, a 4 pin of the isolator U5 is connected with an output end of the overcurrent protection module, a 3.3V pin of the main control MCU is connected to a 9 pin of the isolator U5, a ground pin GND is connected to a 10 pin and a 16 pin of the isolator U5 at the same time, an I1 pin of the main control MCU is connected to a 11 pin of the isolator U5, and an I2 pin of the main control MCU is connected to a 12 pin of the isolator U5.
Further, the overcurrent protection module comprises a second sampling resistor R2, a resistor R22, a capacitor C10 and a second comparator module, wherein the second comparator module comprises a resistor R23, a resistor R24, a resistor R25, a capacitor C11, a capacitor C12 and an operational amplifier U4;
the first end of the second sampling resistor R2 is connected with the first end of the resistor R22; the second end of the resistor R22 and the positive electrode of the capacitor C10 are connected with the same-phase end of the operational amplifier U4, and the opposite-phase end of the operational amplifier U4 is simultaneously connected with the first end of the resistor R23, the first end of the resistor R24 and the positive electrode of the capacitor C11; the power supply end of the operational amplifier U4, the positive electrode of the capacitor C12, the second end of the resistor R23 and the second end of the resistor R25 are simultaneously connected with a 3.3V pin; the output end of the operational amplifier U4 and the first end of the resistor R25 are simultaneously connected with the 4 pin of the isolator U5;
the ground supply end of the operational amplifier U4, the second end of the second sampling resistor R2, the second end of the resistor R24, the negative electrode of the capacitor C10, the negative electrode of the capacitor C11 and the negative electrode of the capacitor C12 are all grounded with the pin AGND.
Further, the second sampling voltage of the second sampling resistor R2 is v_adc2, and the calculation formula of the v_adc2 is as follows:
V_ADC2=R2*I2；
the second preset voltage of the second comparator module is V3, and the calculation formula of V3 is:
V3=R24/(R24+R23)*Vc；
wherein, R2 is the resistance of the second sampling resistor R2, I2 is the current of the second sampling resistor R2, R23 is the resistance of the resistor R23, R24 is the resistance of the resistor R24, and Vc is the voltage value of the 3.3V pin.
A multi-split air conditioning system comprises the AD isolation sampling circuit for power carrier communication.
Compared with the prior art, the invention has at least the following beneficial effects:
1. the AD isolation sampling circuit for power carrier communication can amplify the first sampling voltage through the amplifying module and transmit the first sampling voltage to the first comparator module, the first comparator module compares the amplified first sampling voltage with the first preset voltage and performs analog-to-digital conversion on the comparison result to generate a high/low level first conversion signal, namely, the first conversion signal is digitalized, then the digitalized first conversion signal flows to the isolator module to be isolated, so that the digitalized first conversion signal can stably flow to the main control MCU, then the main control MCU judges whether leakage current exists or not according to the high/low level of the received first conversion signal, if so, the main control MCU performs leakage protection on the circuit, AD sampling isolation for power carrier communication is realized, the accuracy of circuit sampling is improved, and the cost is reduced.
2. The AD isolation sampling circuit for power carrier communication can also compare the second sampling voltage with the second preset voltage through the second comparator module and perform analog-to-digital conversion on the comparison result to generate a second conversion signal with high/low level, namely, the second conversion signal is digitized, then the digitized second conversion signal flows to the isolator module for isolation, so that the digitized second conversion signal can stably flow to the main control MCU, then the main control MCU judges whether overcurrent exists or not according to the high/low level of the received second conversion signal, and if so, the main control MCU performs overcurrent protection on the circuit.
Drawings
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs; the terminology used in the description of the applications herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention; the terms "comprising" and "having" and any variations thereof in the description of the invention and the claims and the description of the drawings above are intended to cover a non-exclusive inclusion. The terms first, second and the like in the description and in the claims or in the above-described figures, are used for distinguishing between different objects and not necessarily for describing a sequential or chronological order.
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following description will briefly explain the drawings used in the embodiments or the description of the prior art, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained according to these drawings without inventive effort to a person skilled in the art.
FIG. 1 is a schematic diagram of one of the circuits of the present invention;
FIG. 2 is a schematic diagram of another circuit of the present invention;
fig. 3 is a block diagram of the module of the present invention.
Reference numerals:
10. a bias voltage module;
20. an amplifying module;
30. a first comparator module;
40. an isolator module;
50. an overcurrent protection module;
60. and a second comparator module.
Detailed Description
In order to make the technical problems, technical schemes and beneficial effects to be solved more clear, the invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention. Thus, reference throughout this specification to one feature will be used in order to describe one embodiment of the invention, not to imply that each embodiment of the invention must be in the proper motion. Furthermore, it should be noted that the present specification describes a number of features. Although certain features may be combined together to illustrate a possible system design, such features may be used in other combinations not explicitly described. Thus, unless otherwise indicated, the illustrated combinations are not intended to be limiting.
The principles and structures of the present invention are described in detail below with reference to the drawings and the examples.
In one embodiment, referring to fig. 1 and 3, the present invention proposes an AD isolation sampling circuit for power carrier communication, comprising:
a bias voltage module 10, which is connected to the amplifying module 20 and provides a bias voltage for the amplifying module 20.
An amplifying module 20, which contains a first sampling resistor; for amplifying the first sampled voltage of the first sampling resistor.
A first comparator module 30 provided with a first preset voltage; the amplifying module 20 is configured to compare the amplified first sampling voltage with the first preset voltage and perform analog-to-digital conversion to generate a first converted signal.
The isolator module 40 is connected to the first comparator module 30, and is configured to isolate the first conversion signal output by the first comparator module 30 and stably transmit the first conversion signal to the main control MCU; the main control MCU can carry out leakage protection on the AD isolation sampling circuit of the power carrier communication, and the leakage protection is as follows:
when a plurality of air-conditioning indoor units in the multi-split air-conditioning system are cascaded, only one air-conditioning indoor unit supplies power to the wire controller, and leakage protection is performed on the rest air-conditioning indoor units which are not supplied with power.
The output end of the bias voltage module 10 is connected with the input end of the amplifying module 20, the output end of the amplifying module 20 is connected with the input end of the first comparator module 30, the output end of the first comparator module 30 is connected with the first input end of the isolator module 40, and the output end of the isolator module 40 is connected with the input end of the main control MCU.
When the power carrier communication power supply system is required to be sampled, leakage current generated by the power carrier communication power supply system and the multi-split air conditioning system using the power carrier communication power supply system is accurately detected and protected.
First, the bias voltage module 10 provides a bias voltage Va to the amplifying module 20, the amplifying module 20 amplifies the first sampling voltage v_adc1 provided by the first sampling resistor, the amplified first sampling voltage V1 flows to the first comparator module 30, and the first comparator module 30 compares the amplified first sampling voltage V1 with the first preset voltage V2 thereof, which may generate the following two cases:
v1 is larger than V2, and the leakage current is generated in the power carrier communication power supply system and the multi-split air conditioning system using the power carrier communication power supply system (the leakage current is that when a plurality of air conditioning indoor units in the multi-split air conditioning system are mutually cascaded, only one air conditioning indoor unit supplies power to a wire controller, and in order to prevent the power supply main board of the rest of the air conditioning indoor units which are not supplied with power from being abnormal, the current detection is needed to be carried out on the power supply main board of the rest of the air conditioning indoor units which are not supplied with power, namely the leakage current for short). When V1 > V2, the first comparator module 30 performs an analog-to-digital conversion on the comparison result to generate a low-level first conversion signal (i.e. the low-level first conversion signal is digitized), and then the isolator module 40 isolates the received low-level first conversion signal, so that the low-level first conversion signal generated by the first comparator module 30 can be stably transmitted to the main control MCU through the isolator module 40, and the main control MCU can perform leakage protection on the power carrier communication power supply system and the multi-split air conditioning system using the power carrier communication power supply system after receiving the low-level first conversion signal.
V1 < V2, the leakage current does not appear in the power carrier communication power supply system and the multi-split air conditioning system using the power carrier communication power supply system, at this time, the first comparator module 30 performs analog-to-digital conversion on the comparison result to generate a high-level first conversion signal (i.e. the high-level first conversion signal is digitized), then the isolator module 40 isolates the received high-level first conversion signal, so that the high-level first conversion signal generated by the first comparator module 30 can be stably conveyed to the main control MCU through the isolator module 40, and the main control MCU does not perform leakage protection on the power carrier communication power supply system and the multi-split air conditioning system using the power carrier communication power supply system after receiving the high-level first conversion signal.
Therefore, the AD isolation sampling circuit for power carrier communication of the present invention can amplify the first sampling voltage v_adc1 through the amplifying module 20, then the amplified first sampling voltage V1 passes through the first comparator module 30, the first comparator module 30 compares the amplified first sampling voltage V1 with the first preset voltage V2, and performs analog-to-digital conversion on the comparison result to generate a high/low level first conversion signal, that is, the first conversion signal is digitized, and then the digitized first conversion signal flows to the isolator module 40 to be isolated, so that the digitized first conversion signal can stably flow to the main control MCU, and then the main control MCU judges whether leakage current exists according to the high/low level of the received first conversion signal, if so, the main control MCU performs leakage protection on the circuit, thus realizing AD sampling isolation for power carrier communication, improving accuracy of circuit sampling, and reducing cost.
In one embodiment, referring to fig. 2 and 3, the AD isolation sampling circuit for power carrier communication further comprises:
an overcurrent protection module 50 includes a second sampling resistor and a second comparator module 60.
The second comparator module 60 is provided with a second preset voltage; the isolator module 40 is configured to compare a second sampling voltage of a second sampling resistor with the second preset voltage and perform analog-to-digital conversion to generate a second converted signal.
Wherein the output of the second comparator module 60 is connected to a second input of the isolator module 40.
The power carrier communication power supply system and the multi-split air conditioning system using the same are also used for preventing excessive current and performing overcurrent protection.
Therefore, the second sampling resistor provides a second sampling voltage v_adc2 to the second comparator module 60, and the second comparator module 60 compares the second sampling voltage v_adc2 with the second preset voltage V3 thereof, which results in two cases:
and V_ADC2 is larger than V3, which indicates that the power carrier communication power supply system and the multi-split air conditioner system using the power carrier communication power supply system have overcurrent, at the moment, the second comparator module 60 can perform analog-to-digital conversion on the comparison result to generate a low-level second conversion signal (namely, the low-level second conversion signal is digitized), then the isolator module 40 isolates the received low-level second conversion signal, so that the low-level second conversion signal generated by the second comparator module 60 can be stably conveyed to the main control MCU through the isolator module 40, and the main control MCU can perform overcurrent protection on the power carrier communication power supply system and the multi-split air conditioner system using the power carrier communication power supply system after receiving the low-level second conversion signal.
And V_ADC < V3, which indicates that the power carrier communication power supply system and the multi-split air conditioner system using the power carrier communication power supply system have no overcurrent, the second comparator module 60 performs analog-digital conversion on the comparison result to generate a high-level second conversion signal (namely, the high-level second conversion signal is digitized), and then the isolator module 40 isolates the received high-level second conversion signal, so that the high-level second conversion signal generated by the second comparator module 60 can be stably conveyed to the main control MCU through the isolator module 40, and the main control MCU does not perform overcurrent protection on the power carrier communication power supply system and the multi-split air conditioner system using the power carrier communication power supply system after receiving the high-level second conversion signal.
In a specific embodiment, referring to fig. 1-2, the amplifying module 20 includes a first sampling resistor R1, a resistor R14, a resistor R15, a resistor R16, a resistor R17, a resistor R18, a capacitor C5, a capacitor C6, a capacitor C7, and an operational amplifier U2.
The first end of the first sampling resistor R1 is connected with the first end of the resistor R16, the second end of the resistor R15 and the negative electrode of the capacitor C5 are simultaneously connected with the same-phase end of the operational amplifier U2, and the first end of the resistor R15 and the positive electrode of the capacitor C5 are simultaneously connected with the output end of the bias voltage module 10; the inverting terminal of the operational amplifier U2 is connected with the first terminal of the resistor R14, the first terminal of the resistor R17 and the anode of the capacitor C6 at the same time; the output end of the operational amplifier U2 is connected with the second end of the resistor R17, the first end of the resistor R18 and the negative electrode of the capacitor C6 at the same time; the second end of the resistor R18 and the positive electrode of the capacitor C7 are simultaneously connected with the input end of the first comparator module 30; the second end of the first sampling resistor R1, the second end of the resistor R14 and the negative electrode of the capacitor C7 are simultaneously connected to the ground pin AGND.
The v_adc1 pin in the amplifying module 20 indicates that it is the first sampling voltage v_adc1 of the first sampling resistor R1, the V1 pin indicates that it is the amplified first sampling voltage V1, and the v_adc1 pin and the V1 pin are labeled in fig. 1-2 for easy understanding.
Therefore, the first sampling voltage v_adc1 generates an amplified first sampling voltage V1 after passing through the operational amplifier U2, and the operational amplifier U2 is preferably a differential proportional operational amplifier.
The calculation formula of the amplified first sampling voltage V1 is:
V1=Va+(R15/R16)*V_ADC1；
V_ADC1=R1*I1；
wherein Va is the bias voltage provided by the bias voltage module 10, R15 is the resistance of the resistor R15, R16 is the resistance of the resistor R16, v_adc1 is the first sampling voltage, R1 is the resistance of the first sampling resistor R1, and I1 is the current of the first sampling resistor R1.
And r14=r16, r15=r17, the calculation formula of V1 can also be:
V1=Va+(R17/R14)*V_ADC1。
in a specific embodiment, referring to fig. 1-2, the bias voltage module 10 includes a resistor R12, a resistor R13, a capacitor C3, a capacitor C4, and an operational amplifier U1.
The same-phase end of the operational amplifier U1 is connected with the first end of the resistor R12, the first end of the resistor R13 and the anode of the capacitor C3 at the same time; the inverting terminal of the operational amplifier U1, the output terminal of the operational amplifier U1 and the positive electrode of the capacitor C4 are simultaneously connected with the first terminal of the resistor R15; the second end of the resistor R12 is connected with a 3.3V pin; the second end of the resistor R13, the negative electrode of the capacitor C3 and the negative electrode of the capacitor C4 are simultaneously connected with the ground pin AGND.
Wherein the V1.65 pin in the bias voltage module 10 indicates that the bias voltage provided by the bias voltage module 10 is preferably 1.65V, the V1.65 pin is labeled in fig. 1-2 for ease of understanding.
In a specific embodiment, referring to fig. 1-2, the first comparator module 30 includes a resistor R19, a resistor R20, a resistor R21, a capacitor C8, a capacitor C9, and an operational amplifier U3.
The non-inverting terminal of the operational amplifier U3 is used as the input terminal of the comparator module, the inverting terminal of the operational amplifier U3 is simultaneously connected with the first terminal of the resistor R19, the first terminal of the resistor R20 and the positive electrode of the capacitor C8, and the power supply terminal of the operational amplifier U3, the second terminal of the resistor R19, the second terminal of the resistor R21, the positive electrode of the capacitor C9 and the first input terminal of the isolator module 40 are simultaneously connected with a 3.3V pin; the output end of the operational amplifier U3 and the first end of the resistor R21 are simultaneously connected with the second input end of the isolator module 40; the ground supply end of the operational amplifier U3, the second end of the resistor R20, the negative electrode of the capacitor C8 and the negative electrode of the capacitor C9 are simultaneously connected to the ground pin AGND.
The V2 pin in the first comparator module 30 indicates that it is the first preset voltage V2, and the V2 pin is labeled in fig. 1-2 for ease of understanding.
The operational amplifier U3 compares the amplified first sampling voltage V1 with a first preset voltage V2, performs analog-to-digital conversion on the comparison result to generate a first conversion signal with a high/low level, and then stably transmits the digitized first conversion signal to the main control MCU through the isolator U5, where the main control MCU determines whether leakage current occurs according to the high/low level of the received first conversion signal.
The first preset voltage of the first comparator module 30 is V2, and the calculation formula of V2 is:
V2=R20/(R20+R19)*Vb；
wherein R19 is the resistance of the resistor R19, R20 is the resistance of the resistor R20, and Vb is the voltage of the 3.3V pin.
In a specific embodiment, referring to fig. 2, the over-current protection module 50 includes a second sampling resistor R2, a resistor R22, a capacitor C10, and a second comparator module 60, where the second comparator module 60 includes a resistor R23, a resistor R24, a resistor R25, a capacitor C11, a capacitor C12, and an operational amplifier U4.
The first end of the second sampling resistor R2 is connected with the first end of the resistor R22; the second end of the resistor R22 and the positive electrode of the capacitor C10 are connected with the same-phase end of the operational amplifier U4, and the opposite-phase end of the operational amplifier U4 is simultaneously connected with the first end of the resistor R23, the first end of the resistor R24 and the positive electrode of the capacitor C11; the power supply end of the operational amplifier U4, the positive electrode of the capacitor C12, the second end of the resistor R23 and the second end of the resistor R25 are simultaneously connected with a 3.3V pin; the output end of the operational amplifier U4 and the first end of the resistor R25 are simultaneously connected with the 4 pin of the isolator U5; the ground supply end of the operational amplifier U4, the second end of the second sampling resistor R2, the second end of the resistor R24, the negative electrode of the capacitor C10, the negative electrode of the capacitor C11 and the negative electrode of the capacitor C12 are all grounded with the pin AGND.
The V3 pin in the second comparator module 60 indicates that it is the second preset voltage V3, and the V3 pin is labeled in fig. 2 for ease of understanding. And the operational amplifier U4 is preferably a differential proportional operational amplifier.
The operational amplifier U4 compares the second sampling voltage with the second preset voltage V3, performs analog-to-digital conversion on the comparison result to generate a second conversion signal with a high/low level, and then stably transmits the digitized second conversion signal to the main control MCU through the isolator U5, and the main control MCU determines whether an overcurrent occurs according to the high/low level of the received second conversion signal.
The second sampling voltage of the second sampling resistor R2 is v_adc2, and the calculation formula of the v_adc2 is as follows:
V_ADC2=R2*I2；
the second preset voltage of the second comparator module 60 is V3, and the calculation formula of V3 is:
V3=R24/(R24+R23)*Vc；
wherein, R2 is the resistance of the second sampling resistor R2, I2 is the current of the second sampling resistor R2, R23 is the resistance of the resistor R23, R24 is the resistance of the resistor R24, and Vc is the voltage value of the 3.3V pin.
In a specific embodiment, and referring to FIGS. 1-2, the isolator module 40 includes an isolator U5; the 1 foot of isolator U5 is connected with 3.3V pin, the 2 foot and the 8 foot of isolator U5 are connected with ground pin AGND, the 3 foot of isolator U5 with operational amplifier U3's output is connected, the 4 foot of isolator U5 with overcurrent protection module 50's output is connected, the 9 foot of isolator U5 is connected with master control MCU's 3.3V pin, the 10 foot and the 16 foot of isolator U5 are connected with ground pin GND simultaneously, the 11 foot of isolator U5 is connected with master control MCU's I1 foot, the 12 foot of isolator U5 is connected with master control MCU's I2 foot.
The isolator U5 isolates the received digitized first conversion signal or second conversion signal, so as to prevent the first conversion signal or second conversion signal from being interfered by the ground pin AGND and the ground pin GND connected to the isolator U5, so that the digitized first conversion signal or second conversion signal can be stably and safely transmitted to the main control MCU, and then the main control MCU determines whether leakage current occurs according to the received high/low level of the digitized first conversion signal, or the main control MCU determines whether overcurrent occurs according to the received high/low level of the digitized second conversion signal. At the same time, the circuit can only leak current or overcurrent.
In one embodiment, the invention further provides a multi-split air conditioning system, which comprises the AD isolation sampling circuit for power carrier communication.
In a specific embodiment, referring to FIGS. 1-2, bias voltage module 10 includes resistor R12, resistor R13, capacitor C3, capacitor C4, and operational amplifier U1; the amplifying module 20 includes a first sampling resistor R1, a resistor R14, a resistor R15, a resistor R16, a resistor R17, a resistor R18, a capacitor C5, a capacitor C6, a capacitor C7, and an operational amplifier U2; the first comparator module 30 includes a resistor R19, a resistor R20, a resistor R21, a capacitor C8, a capacitor C9, and an operational amplifier U3; the overcurrent protection module 50 includes a second sampling resistor R2, a resistor R22, a capacitor C10, a resistor R23, a resistor R24, a resistor R25, a capacitor C11, a capacitor C12, and an operational amplifier U4; the isolator module 40 includes an isolator U5.
The same-phase end of the operational amplifier U1 is connected with the first end of the resistor R12, the first end of the resistor R13 and the anode of the capacitor C3 at the same time; the inverting terminal of the operational amplifier U1, the output terminal of the operational amplifier U1 and the positive electrode of the capacitor C4 are simultaneously connected with the first terminal of the resistor R15, the first terminal of the resistor R15 is also connected with the positive electrode of the capacitor C5, and the second terminal of the resistor R15, the second terminal of the resistor R16 and the negative electrode of the capacitor C5 are simultaneously connected with the same-phase terminal of the operational amplifier U2; the first end of the resistor R16 is connected with the first end of the first sampling resistor R1; the inverting terminal of the operational amplifier U2 is connected with the first terminal of the resistor R14, the first terminal of the resistor R17 and the anode of the capacitor C6 at the same time; the output end of the operational amplifier U2 is connected with the second end of the resistor R17, the first end of the resistor R18 and the negative electrode of the capacitor C6 at the same time; the second end of the resistor R18 and the positive electrode of the capacitor C7 are connected with the same-phase end of the operational amplifier U3 at the same time; the inverting terminal of the operational amplifier U3 is connected with the first terminal of the resistor R19, the first terminal of the resistor R20 and the positive electrode of the capacitor C8 at the same time, and the output terminal of the operational amplifier U3 and the first terminal of the resistor R21 are connected with the 3 pin of the isolator U5 at the same time.
The first end of the second sampling resistor R2 is connected with the first end of the resistor R22; the second end of the resistor R22 and the positive electrode of the capacitor C10 are connected with the same-phase end of the operational amplifier U4, and the opposite-phase end of the operational amplifier U4 is simultaneously connected with the first end of the resistor R23, the first end of the resistor R24 and the positive electrode of the capacitor C11; the output end of the operational amplifier U4 and the first end of the resistor R25 are simultaneously connected with the 4 pins of the isolator U5, the 9 pins of the isolator U5 are connected with the 3.3V pin of the main control MCU, the 10 pins and the 16 pins of the isolator U5 are simultaneously connected with the ground pin GND, the 11 pin of the isolator U5 is connected with the I1 pin of the main control MCU, and the 12 pin of the isolator U5 is connected with the I2 pin of the main control MCU.
The power supply end of the operational amplifier U3, the power supply end of the operational amplifier U4, the second end of the resistor R12, the second end of the resistor R19, the second end of the resistor R21, the second end of the resistor R23, the second end of the resistor R25, the positive electrode of the capacitor C9, the positive electrode of the capacitor C12 and the 1 pin of the isolator U5 are simultaneously connected with 3.3V pins.
The second end of the first sampling resistor R1, the second end of the second sampling resistor R2, the second end of the resistor R13, the second end of the resistor R14, the second end of the resistor R20, the second end of the resistor R24, the negative electrode of the capacitor C3, the negative electrode of the capacitor C4, the negative electrode of the capacitor C7, the negative electrode of the capacitor C8, the negative electrode of the capacitor C9, the negative electrode of the capacitor C10, the negative electrode of the capacitor C11, the negative electrode of the capacitor C12, the ground supply end of the operational amplifier U3, the ground supply end of the operational amplifier U4, and the 2 pins and the 8 pins of the isolator U5 are simultaneously connected with the ground pin AGND.
Referring to fig. 2-3, the method for using the AD isolation sampling circuit for power carrier communication of the present invention comprises:
first, the bias voltage module 10 provides a bias voltage to the amplifying module 20, the bias voltage is 1.65V, the amplifying module 20 amplifies the first sampling voltage v_adc1, the first comparator module 30 compares the amplified first sampling voltage V1 with the first preset voltage V2 and generates a first conversion signal with high/low level, the first comparator module 30 digitizes the first conversion signal, the digitized first conversion signal flows to the isolator module 40 for isolation, so that the digitized first conversion signal can be stably transmitted to the main control MCU, and then the main control MCU determines whether leakage current exists according to the high/low level of the received first conversion signal, if so, the main control MCU performs leakage protection on the circuit.
Thus, the amplification module 20 amplifies the tiny first sampling voltage V_ADC1, the first comparator module 30 realizes analog-to-digital conversion, and then the isolation module 40 is used for isolating, so that AD sampling isolation of power carrier communication is realized, the accuracy of circuit sampling is improved, and the cost is reduced.
The second comparator module 60 compares the second sampling voltage v_adc2 with the second preset voltage V3 and generates a second conversion signal with high/low level, the second comparator module 60 digitizes the second conversion signal, the digitized second conversion signal flows to the isolator module 40 for isolation, the digitized second conversion signal can be stably transmitted to the main control MCU, and the main control MCU determines whether there is an overcurrent according to the high/low level of the received second conversion signal, if yes, the main control MCU performs an overcurrent protection on the circuit.
It is apparent that the above-described embodiments are only some embodiments of the present invention, but not all embodiments, and the preferred embodiments of the present invention are shown in the drawings, which do not limit the scope of the patent claims. This invention may be embodied in many different forms, but rather, embodiments are provided in order to provide a thorough and complete understanding of the present disclosure. Although the invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments described in the foregoing description, or equivalents may be substituted for elements thereof. All equivalent structures made by the content of the specification and the drawings of the invention are directly or indirectly applied to other related technical fields, and are also within the scope of the invention.
Claims (8)
1. An AD isolation sampling circuit for power carrier communication, comprising:
the bias voltage module is used for being connected with the amplifying module and providing bias voltage for the amplifying module;
an amplifying module containing a first sampling resistor; amplifying a first sampling voltage of the first sampling resistor;
a first comparator module provided with a first preset voltage; the amplifying module is used for connecting the amplified first sampling voltage with the first preset voltage, comparing the amplified first sampling voltage with the first preset voltage and performing analog-digital conversion to generate a first conversion signal;
the overcurrent protection module comprises a second sampling resistor and a second comparator module; the second comparator module is provided with a second preset voltage; the isolator module is used for comparing a second sampling voltage of a second sampling resistor with the second preset voltage and performing analog-digital conversion to generate a second conversion signal;
the isolator module is used for being connected with the first comparator module, isolating the first conversion signal output by the first comparator module from the second conversion signal output by the second comparator module and stably conveying the signals to the main control MCU;
the amplifying module comprises a first sampling resistor R1, a resistor R14, a resistor R15, a resistor R16, a resistor R17, a resistor R18, a capacitor C5, a capacitor C6, a capacitor C7 and an operational amplifier U2; the first comparator module comprises a resistor R19, a resistor R20, a resistor R21, a capacitor C8, a capacitor C9 and an operational amplifier U3; the isolator module comprises an isolator U5;
the first end of the first sampling resistor R1 is connected with the first end of the resistor R16, the second end of the resistor R15 and the negative electrode of the capacitor C5 are simultaneously connected with the same-phase end of the operational amplifier U2, and the first end of the resistor R15 and the positive electrode of the capacitor C5 are simultaneously connected with the output end of the bias voltage module;
the inverting terminal of the operational amplifier U2 is connected with the first terminal of the resistor R14, the first terminal of the resistor R17 and the anode of the capacitor C6 at the same time; the output end of the operational amplifier U2 is connected with the second end of the resistor R17, the first end of the resistor R18 and the negative electrode of the capacitor C6 at the same time; the second end of the resistor R18 and the positive electrode of the capacitor C7 are simultaneously connected with the same-phase end of the operational amplifier U3, the inverting end of the operational amplifier U3 is simultaneously connected with the first end of the resistor R19, the first end of the resistor R20 and the positive electrode of the capacitor C8, and the output end of the operational amplifier U3 and the first end of the resistor R21 are simultaneously connected with the second input end of the isolator module;
the power supply end of the operational amplifier U3, the second end of the resistor R19, the second end of the resistor R21, the anode of the capacitor C9 and the first input end of the isolator module are simultaneously connected with a 3.3V pin;
the second end of the first sampling resistor R1, the ground supply end of the operational amplifier U3, the second end of the resistor R14, the second end of the resistor R20, the negative electrode of the capacitor C7, the negative electrode of the capacitor C8 and the negative electrode of the capacitor C9 are simultaneously connected with the ground pin AGND.
2. The AD isolation sampling circuit for power carrier communication according to claim 1, wherein the first sampling voltage amplified by the amplifying module is V1, and a calculation formula of V1 is:
V1=Va+(R15/R16)*V_ADC1；
V_ADC1=R1*I1；
wherein Va is the bias voltage provided by the bias voltage module, R15 is the resistance of the resistor R15, R16 is the resistance of the resistor R16, v_adc1 is the first sampling voltage, R1 is the resistance of the first sampling resistor R1, and I1 is the current of the first sampling resistor R1.
3. The AD isolation sampling circuit for power carrier communication of claim 1, wherein the bias voltage module comprises a resistor R12, a resistor R13, a capacitor C3, a capacitor C4, and an operational amplifier U1;
the same-phase end of the operational amplifier U1 is connected with the first end of the resistor R12, the first end of the resistor R13 and the anode of the capacitor C3 at the same time; the inverting terminal of the operational amplifier U1, the output terminal of the operational amplifier U1 and the positive electrode of the capacitor C4 are simultaneously connected with the first terminal of the resistor R15; the second end of the resistor R12 is connected with a 3.3V pin; the second end of the resistor R13, the negative electrode of the capacitor C3 and the negative electrode of the capacitor C4 are simultaneously connected with the ground pin AGND.
4. The AD isolation sampling circuit for power carrier communication according to claim 1, wherein the first preset voltage of the first comparator module is V2, and a calculation formula of V2 is:
V2=R20/(R20+R19)*Vb；
wherein R19 is the resistance of the resistor R19, R20 is the resistance of the resistor R20, and Vb is the voltage of the 3.3V pin.
5. The AD isolated sampling circuit for power carrier communication of claim 3, wherein the isolator module comprises an isolator U5;
the high-voltage power supply is characterized in that a 3.3V pin is connected to a 1 pin of the isolator U5, a ground pin AGND is connected to a 2 pin and a 8 pin of the isolator U5, a 3 pin of the isolator U5 is connected with an output end of the operational amplifier U3, a 4 pin of the isolator U5 is connected with an output end of the overcurrent protection module, a 3.3V pin of the main control MCU is connected to a 9 pin of the isolator U5, a ground pin GND is connected to a 10 pin and a 16 pin of the isolator U5 at the same time, an I1 pin of the main control MCU is connected to a 11 pin of the isolator U5, and an I2 pin of the main control MCU is connected to a 12 pin of the isolator U5.
6. The AD isolated sampling circuit of claim 5, wherein the over-current protection module comprises a second sampling resistor R2, a resistor R22, a capacitor C10, and a second comparator module comprising a resistor R23, a resistor R24, a resistor R25, a capacitor C11, a capacitor C12, and an operational amplifier U4;
the first end of the second sampling resistor R2 is connected with the first end of the resistor R22; the second end of the resistor R22 and the positive electrode of the capacitor C10 are connected with the same-phase end of the operational amplifier U4, and the opposite-phase end of the operational amplifier U4 is simultaneously connected with the first end of the resistor R23, the first end of the resistor R24 and the positive electrode of the capacitor C11; the power supply end of the operational amplifier U4, the positive electrode of the capacitor C12, the second end of the resistor R23 and the second end of the resistor R25 are simultaneously connected with a 3.3V pin; the output end of the operational amplifier U4 and the first end of the resistor R25 are simultaneously connected with the 4 pin of the isolator U5;
the ground supply end of the operational amplifier U4, the second end of the second sampling resistor R2, the second end of the resistor R24, the negative electrode of the capacitor C10, the negative electrode of the capacitor C11 and the negative electrode of the capacitor C12 are all grounded with the pin AGND.
7. The AD isolation sampling circuit for power carrier communication according to claim 6, wherein the second sampling voltage of the second sampling resistor R2 is v_adc2, and the calculation formula of the v_adc2 is:
V_ADC2=R2*I2；
the second preset voltage of the second comparator module is V3, and the calculation formula of V3 is:
V3=R24/(R24+R23)*Vc；
wherein, R2 is the resistance of the second sampling resistor R2, I2 is the current of the second sampling resistor R2, R23 is the resistance of the resistor R23, R24 is the resistance of the resistor R24, and Vc is the voltage value of the 3.3V pin.
8. A multi-split air conditioning system comprising the AD isolation sampling circuit for power carrier communication of any one of claims 1-7.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311728413.7A CN117439606B (en) | 2023-12-15 | 2023-12-15 | AD isolation sampling circuit for power carrier communication and multi-split air conditioning system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311728413.7A CN117439606B (en) | 2023-12-15 | 2023-12-15 | AD isolation sampling circuit for power carrier communication and multi-split air conditioning system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN117439606A CN117439606A (en) | 2024-01-23 |
| CN117439606B true CN117439606B (en) | 2024-04-02 |
Family
ID=89550143
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311728413.7A Active CN117439606B (en) | 2023-12-15 | 2023-12-15 | AD isolation sampling circuit for power carrier communication and multi-split air conditioning system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117439606B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117997144B (en) * | 2024-04-02 | 2024-06-07 | 珠海格力电器股份有限公司 | Main control drive integrated circuit, controller main board and air conditioning equipment |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203054061U (en) * | 2012-12-06 | 2013-07-10 | 杭州成功超声电源技术有限公司 | Ultrasonic power supply current detection circuit |
| CN205811508U (en) * | 2016-07-27 | 2016-12-14 | 深圳市科华恒盛科技有限公司 | A kind of output overcurrent protection circuit |
| CN113671409A (en) * | 2021-08-12 | 2021-11-19 | 厦门京福通信有限公司 | Current acquisition protection circuit |
| CN113899940A (en) * | 2021-08-24 | 2022-01-07 | 北京京医合符医药科技发展有限公司 | Acquisition and test circuit system for narrow pulse current |
| CN219067841U (en) * | 2022-12-16 | 2023-05-23 | 深圳拓邦股份有限公司 | Overcurrent protection circuit and drive circuit device |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115113667A (en) * | 2022-02-28 | 2022-09-27 | 厦门松霖科技股份有限公司 | Little current constant current output circuit and little current gondola water faucet |
-
2023
- 2023-12-15 CN CN202311728413.7A patent/CN117439606B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN203054061U (en) * | 2012-12-06 | 2013-07-10 | 杭州成功超声电源技术有限公司 | Ultrasonic power supply current detection circuit |
| CN205811508U (en) * | 2016-07-27 | 2016-12-14 | 深圳市科华恒盛科技有限公司 | A kind of output overcurrent protection circuit |
| CN113671409A (en) * | 2021-08-12 | 2021-11-19 | 厦门京福通信有限公司 | Current acquisition protection circuit |
| CN113899940A (en) * | 2021-08-24 | 2022-01-07 | 北京京医合符医药科技发展有限公司 | Acquisition and test circuit system for narrow pulse current |
| CN219067841U (en) * | 2022-12-16 | 2023-05-23 | 深圳拓邦股份有限公司 | Overcurrent protection circuit and drive circuit device |
Non-Patent Citations (1)
| Title |
|---|
| 电力载波电源电路的高可靠性设计;田家乐等;《电测与仪表》;20171110;第54卷(第21期);第37-41页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN117439606A (en) | 2024-01-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN117439606B (en) | AD isolation sampling circuit for power carrier communication and multi-split air conditioning system | |
| US8190934B2 (en) | Solid state power controllers including current sensing circuitry is configured to bias a general signal to a predetermined level in order to substantially eliminate the offset error in an amplifier and an A/D converter | |
| US20180149688A1 (en) | Grounding detection apparatus, control method thereof and pool system | |
| CN106645905B (en) | Output voltage isolation sampling circuit of high-voltage frequency converter | |
| EP2207246B1 (en) | Earth leakage detection circuit | |
| US10564186B2 (en) | Current sense amplifier architecture and level shifter | |
| CN111060734A (en) | High-side current detection device and system | |
| US20240283354A1 (en) | Rectifier with signal reconstruction | |
| US20150323571A1 (en) | Current sensing system and method | |
| CN117559610B (en) | Emergency protection system for electric automobile during high-voltage charging | |
| CN100432688C (en) | Sensor signal detection device | |
| CN113671409A (en) | Current acquisition protection circuit | |
| US20050057219A1 (en) | Apparatus and method for cell voltage monitoring | |
| US6730884B2 (en) | Protective circuit for electrical heating element | |
| CN208971491U (en) | A kind of Sense terminal compensation circuit with amplitude limitation function | |
| CN112034391A (en) | Acquisition circuit of power system relay protection device and mutual inductor detection method | |
| CN218124313U (en) | Matched resistance protection circuit and communication system | |
| CN211505778U (en) | Insulation detection device | |
| CN214703797U (en) | Cubical switchboard heater fault detection device | |
| CN112255937B (en) | Automobile combination instrument control circuit capable of detecting low-side load open circuit | |
| CN114167229B (en) | Test power supply insulation fault monitoring and searching system and method | |
| CN215498411U (en) | Industrial UPS power supply | |
| CN219997177U (en) | Current sampling circuit, vehicle and electric equipment | |
| CN221595232U (en) | Signal line detection circuit and converter device | |
| US20180259210A1 (en) | Indoor climate control system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |