CN113885479B - Valve control circuit and diagnostic circuit thereof - Google Patents
Valve control circuit and diagnostic circuit thereof Download PDFInfo
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- CN113885479B CN113885479B CN202111259099.3A CN202111259099A CN113885479B CN 113885479 B CN113885479 B CN 113885479B CN 202111259099 A CN202111259099 A CN 202111259099A CN 113885479 B CN113885479 B CN 113885479B
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- 238000005070 sampling Methods 0.000 claims abstract description 53
- 238000001514 detection method Methods 0.000 claims abstract description 35
- 238000003745 diagnosis Methods 0.000 claims abstract description 27
- 230000001052 transient effect Effects 0.000 claims description 9
- 238000000034 method Methods 0.000 description 11
- 238000010586 diagram Methods 0.000 description 10
- 238000006243 chemical reaction Methods 0.000 description 4
- 230000001105 regulatory effect Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000002093 peripheral effect Effects 0.000 description 2
- 208000025274 Lightning injury Diseases 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 230000002441 reversible effect Effects 0.000 description 1
- 238000004092 self-diagnosis Methods 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B23/00—Testing or monitoring of control systems or parts thereof
- G05B23/02—Electric testing or monitoring
- G05B23/0205—Electric testing or monitoring by means of a monitoring system capable of detecting and responding to faults
- G05B23/0208—Electric testing or monitoring by means of a monitoring system capable of detecting and responding to faults characterized by the configuration of the monitoring system
- G05B23/0213—Modular or universal configuration of the monitoring system, e.g. monitoring system having modules that may be combined to build monitoring program; monitoring system that can be applied to legacy systems; adaptable monitoring system; using different communication protocols
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B2219/00—Program-control systems
- G05B2219/20—Pc systems
- G05B2219/24—Pc safety
- G05B2219/24065—Real time diagnostics
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- Automation & Control Theory (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Abstract
The application discloses a valve control circuit and a diagnostic circuit of the valve control circuit, and relates to the field of circuit detection. The circuit comprises a first DAC, a voltage comparison circuit, a sampling resistor and a differential amplifier; the first DAC is connected with an MCU in the valve control circuit and is used for converting data transmitted by the MCU to obtain a first voltage value; the differential amplifier is connected with the sampling resistor and is used for amplifying the voltage value of the sampling resistor to obtain a second voltage value; the input end of the voltage comparison circuit is respectively connected with the first DAC and the differential amplifier and is used for determining a diagnosis result according to the first voltage value and the second voltage value; the output end of the voltage comparison circuit is connected with the interrupt pin of the MCU. The circuit diagnoses the channel of the valve control circuit in real time through the voltage comparison circuit, and simultaneously outputs a diagnosis result in an interrupt triggering mode, thereby having better instantaneity.
Description
Technical Field
The present disclosure relates to the field of circuit detection, and in particular, to a valve control circuit and a diagnostic circuit for the valve control circuit.
Background
The analog output modules (Analog Output Module, AO modules) used for controlling the regulating valve in industry are mostly 4-20 mA current type output modules, and in the safety instrument system, the requirement on module self-diagnosis is very high. Fig. 1 is a schematic structural diagram of a conventional valve adjusting circuit and a diagnostic circuit thereof, as shown in fig. 1, the principle of a current output type AO module is mainly that a micro control unit (Micro Control Unit, MCU) configures registers inside a DAC to output different voltage values according to needs through a Digital interface with a Digital-to-analog-Analog Conversion (DAC), and a voltage/current converting circuit (V/I circuit) completes conversion from voltage to current, so as to control the opening of an adjusting valve. Whereas conventional channel failure diagnosis uses Analog-to-Digital Conversion (ADC) read-back.
In the traditional diagnosis of channel faults, as the interface between the MCU and the ADC is in a query mode, the MCU is required to actively query the ADC interface, and the fault cannot be diagnosed in real time in a non-interrupt triggering mode.
In view of the above, it is a urgent need for those skilled in the art to design a diagnostic circuit for a valve control circuit capable of detecting a circuit failure in real time.
Disclosure of Invention
The purpose of the present application is to provide a valve control circuit and a diagnostic circuit of the valve control circuit, which are used for solving the problem that the diagnosis of faults in the traditional valve control circuit cannot be implemented due to the inquiry mode between an MCU and an ADC.
In order to solve the above technical problems, the present application provides a diagnostic circuit of a valve control circuit, including: a first DAC10, a voltage comparison circuit 11, a sampling resistor and a differential amplifier 12;
the first DAC10 is connected with an MCU in the valve control circuit and is used for converting data transmitted by the MCU to obtain a first voltage value; the differential amplifier 12 is connected with the sampling resistor and is used for amplifying the voltage value of the sampling resistor to obtain a second voltage value; the input end of the voltage comparison circuit 11 is respectively connected with the first DAC10 and the differential amplifier 12, and is used for determining a diagnosis result according to the first voltage value and the second voltage value;
the output end of the voltage comparison circuit 11 is connected with the interrupt pin of the MCU.
Preferably, the circuit further comprises a short circuit detection circuit;
the input end of the short circuit detection circuit is respectively connected with the first end of the sampling resistor and the output end of the reference power supply, and is used for determining a diagnosis result according to the third voltage value of the first end of the sampling resistor and the reference voltage value output by the reference power supply; and the output end of the short circuit detection circuit is connected with the interrupt pin of the MCU.
Preferably, the short circuit detection circuit includes a comparator and a first resistor;
the non-inverting input end of the comparator is connected with the first end of the first resistor, the second end of the first resistor is connected with the first end of the sampling resistor, the inverting input end of the comparator is connected with a reference power supply, and the output end of the comparator is used as the output end of the short circuit detection circuit.
Preferably, the voltage comparing circuit 11 includes a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, a first operational amplifier, a second operational amplifier, a third operational amplifier, and a first diode;
the output end of the first DAC10 is connected with the first end of the second resistor, and the second end of the second resistor is connected with the first end of the third resistor and the inverting input end of the first operational amplifier; the output end of the differential amplifier 12 is connected with the first end of the fourth resistor, the second end of the fourth resistor is connected with the first end of the fifth resistor and the non-inverting input end of the first operational amplifier, and the second end of the fifth resistor is grounded; the output end of the first operational amplifier is connected with the second end of the third resistor and the first end of the sixth resistor, the second end of the sixth resistor is connected with the first end of the seventh resistor and the inverting input end of the second operational amplifier, the first end of the eighth resistor is connected with the non-inverting input end of the second operational amplifier, and the second end of the eighth resistor is grounded; the output end of the second operational amplifier is connected with the anode of the first diode, and the cathode of the first diode is connected with the second end of the seventh resistor and the non-inverting input end of the third operational amplifier; the first end of the ninth resistor is connected with the first end of the tenth resistor and the inverting input end of the third operational amplifier, and the second end of the ninth resistor is grounded; the second end of the tenth resistor is connected with the output end of the third operational amplifier, and the output end of the third operational amplifier is connected with the interrupt pin of the MCU;
the first end of the second resistor and the first end of the fourth resistor are respectively input ends of the voltage comparison circuit 11, and the output end of the third operational amplifier is an output end of the voltage comparison circuit 11.
Preferably, the circuit further comprises a protection circuit, wherein the protection circuit comprises an eleventh resistor and a second diode;
the first end of the eleventh resistor is connected with the first end of the sampling resistor and the cathode of the second diode, and the second end of the eleventh resistor is connected with the first end of the load resistor; and the anode of the second diode and the second end of the load resistor are grounded and are used for setting the reference voltage value and the protection circuit.
Preferably, the eleventh resistor is a positive temperature coefficient thermistor.
Preferably, the second diode is a transient diode.
Preferably, the first DAC10 and the MCU are connected using an SPI bus.
In order to solve the above problems, the embodiment of the present application further provides a valve control circuit, which includes the diagnostic circuit of the valve control circuit.
The diagnostic circuit of the valve control circuit comprises a first DAC, a voltage comparison circuit, a sampling resistor and a differential amplifier; the first DAC is connected with an MCU in the valve control circuit and is used for converting data transmitted by the MCU to obtain a first voltage value; the differential amplifier is connected with the sampling resistor and is used for amplifying the voltage value of the sampling resistor to obtain a second voltage value; the input end of the voltage comparison circuit is respectively connected with the first DAC and the differential amplifier and is used for determining a diagnosis result according to the first voltage value and the second voltage value; the output end of the voltage comparison circuit is connected with the interrupt pin of the MCU. The circuit diagnoses the channel of the valve control circuit in real time through the voltage comparison circuit, and simultaneously outputs a diagnosis result in an interrupt triggering mode, thereby having better instantaneity.
In addition, the application also provides a valve control circuit, and the diagnostic circuit comprising the valve control circuit has the same effect.
Drawings
For a clearer description of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described, it being apparent that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a conventional valve regulating circuit and a diagnostic circuit thereof;
FIG. 2 is a schematic diagram of a diagnostic circuit of a valve control circuit according to an embodiment of the present disclosure;
FIG. 3 is a schematic diagram of a diagnostic circuit of another valve control circuit according to an embodiment of the present disclosure;
fig. 4 is a schematic structural diagram of a voltage comparison circuit according to an embodiment of the present disclosure;
fig. 5 is a schematic structural diagram of a protection circuit according to an embodiment of the present application.
Wherein 10 is a first DAC,11 is a voltage comparison circuit, and 12 is a differential amplifier.
Detailed Description
The following description of the technical solutions in the embodiments of the present application will be made clearly and completely with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are only some embodiments of the present application, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments herein without making any inventive effort are intended to fall within the scope of the present application.
The core of the application is to provide a valve control circuit and a diagnosis circuit of the valve control circuit, which are used for solving the problem that the diagnosis of faults in the traditional valve control circuit cannot be implemented due to the inquiry mode between an MCU and an ADC.
In order to provide a better understanding of the present application, those skilled in the art will now make further details of the present application with reference to the drawings and detailed description.
Fig. 2 is a schematic structural diagram of a diagnostic circuit of a valve control circuit according to an embodiment of the present application, where, as shown in fig. 2, the diagnostic circuit of the valve control circuit includes: a first DAC10, a voltage comparison circuit 11, a sampling resistor Rs, and a differential amplifier 12; the first DAC10 is connected with an MCU in the valve control circuit and is used for converting data transmitted by the MCU to obtain a first voltage value; the differential amplifier 12 is connected with the sampling resistor Rs and is used for amplifying the voltage value of the sampling resistor Rs to obtain a second voltage value; the input end of the voltage comparison circuit 11 is respectively connected with the first DAC10 and the differential amplifier 12 and is used for determining a diagnosis result according to the first voltage value and the second voltage value; the output end of the voltage comparison circuit 11 is connected with the interrupt pin of the MCU.
When the valve control circuit works, the MCU configures a register in the DAC to output different voltage values according to the requirement through a digital interface between the MCU and the channel DAC; the V/I circuit finishes the conversion from voltage to current, thereby realizing the control of the opening degree of the regulating valve. It can be understood that in fig. 2, assuming that the voltage value output by the channel DAC is Vdac, the MCU outputs the same data to the first DAC10 and configures the voltage value output by the first DAC to be the same as the voltage value of the channel DAC, i.e., vdac, and this voltage value is the first voltage value; meanwhile, the output current of the V/I circuit is IO=Vdac/Rset; and the voltage on the sampling resistor Rs connected to the V/I circuit is vrs=vdac/rset×rs; the differential amplifier 12 is connected with the sampling resistor Rs and is used for amplifying the voltage of the sampling resistor Rs; if the gain of the differential amplifier 12 is set to gain=rset/Rs, the differential amplifier 12 outputs a voltage vdif=vrs×gain= (vdac×rs/Rset) ×(Rset/Rs) =vdac, so that the voltage of the differential amplifier 12 can be made exactly equal to Vdac with this gain setting. The voltage value of the amplified sampling resistor Rs output by the differential amplifier 12 is the second voltage value.
When judging whether the channel is broken, the voltage comparison circuit 11 respectively acquires a first voltage value of the first DAC10 and a second voltage value of the differential amplifier 12, if the difference value of the first voltage value and the second voltage value is within the error precision range, the fact that the channel is not broken can be confirmed, the voltage comparison circuit 11 outputs 1 to an interrupt pin of the MCU, and the MCU continues to work; if the difference between the first voltage value and the second voltage value exceeds the error precision range, the channel is broken, the voltage comparison circuit 11 outputs 0 to the interrupt pin of the MCU, and the MCU interrupts the current process.
It will be appreciated that setting the gain of the differential amplifier 12 to gain=rset/Rs is only one preferred embodiment; if the gain value of the differential amplifier 12 is increased or reduced on the basis of the gain value, the voltage value output by the differential amplifier 12 is also relatively changed, and in order to accurately judge the channel condition, the error accuracy range of the phase difference value of the first voltage value and the second voltage value is adjusted to adapt to the changed gain, so that whether the channel is disconnected or not is accurately judged. It should be noted that, in this embodiment, the specific structure of the voltage comparison circuit 11 is not limited, and it is only required to ensure that the first voltage value and the second voltage value can be compared within a certain error range, and a corresponding interrupt signal is sent to the interrupt pin of the MCU according to the comparison result, which depends on the specific implementation situation.
In this embodiment, the diagnostic circuit of the valve control circuit includes a first DAC, a voltage comparison circuit, a sampling resistor, and a differential amplifier; the first DAC is connected with an MCU in the valve control circuit and is used for converting data transmitted by the MCU to obtain a first voltage value; the differential amplifier is connected with the sampling resistor and is used for amplifying the voltage value of the sampling resistor to obtain a second voltage value; the input end of the voltage comparison circuit is respectively connected with the first DAC and the differential amplifier and is used for determining a diagnosis result according to the first voltage value and the second voltage value; the output end of the voltage comparison circuit is connected with the interrupt pin of the MCU. The circuit diagnoses the channel of the valve control circuit in real time through the voltage comparison circuit, and simultaneously outputs a diagnosis result in an interrupt triggering mode, thereby having better instantaneity.
In the above embodiment, the diagnosis of the channel disconnection is performed by the voltage comparison circuit 11; in this embodiment, a short-circuit detection circuit is added, and the short-circuit detection circuit includes:
the input end of the short circuit detection circuit is respectively connected with the first end of the sampling resistor Rs and the output end of the reference power supply, and is used for determining a diagnosis result according to the third voltage value of the first end of the sampling resistor Rs and the reference voltage value output by the reference power supply; the output end of the short circuit detection circuit is connected with the interrupt pin of the MCU.
It will be appreciated that one input terminal of the short circuit detection circuit is connected to the first terminal of the sampling resistor Rs, the first terminal of the sampling resistor Rs is connected to the load resistor RL, and the short circuit detection circuit detects the conduction condition from the first terminal of the sampling resistor Rs to the circuit on the load resistor RL side. The short circuit detection circuit detects a voltage value at a first end of the sampling resistor Rs, wherein the voltage value at the point is Va=Ia×RL, and the voltage value is a third voltage value; wherein ia=io, i.e. the current value at this point is the current value output by the V/I circuit. The other input end of the short circuit detection circuit is connected with a reference power supply, and the reference power supply outputs a reference voltage value. In the detection process, the short circuit detection circuit compares the third voltage value with the reference voltage value; when the third voltage value is detected to be equal to the reference voltage value, short circuit does not occur from the first end of the sampling resistor Rs to the load resistor RL, the short circuit detection circuit sends 1 to an interrupt pin of the MCU, and the MCU continues to work; when the third voltage value is detected to be different from the reference voltage value, for example, the third voltage value is far smaller than the reference voltage value, a short circuit condition occurs from the first end of the sampling resistor Rs to the load resistor RL, the short circuit detection circuit sends 0 to the interrupt pin of the MCU, and the MCU stops the current process.
It should be noted that, in this embodiment, the specific structure of the short circuit detection circuit is not limited, and it is only required to ensure that the comparison between the third voltage value at the first end of the sampling resistor Rs and the reference voltage value can be achieved, and the corresponding interrupt signal can be output to the interrupt pin of the MCU according to the comparison result, which depends on the specific implementation situation; meanwhile, the setting mode of the reference voltage value output by the reference power supply is not limited, and is determined according to a specific embodiment.
In the embodiment, the short circuit detection circuit for detecting the sampling resistor to the load resistor is added on the basis of the embodiment, so that the diagnosis of the rear-end load resistor circuit is perfected for the diagnosis circuit of the valve control circuit; meanwhile, the diagnosis result of the short circuit detection circuit is transmitted to the interrupt pin of the MCU in an interrupt triggering mode, so that the real-time performance is good.
In the above embodiments, the specific configuration of the short-circuit detection circuit is not limited, and depends on the specific implementation. Fig. 3 is a schematic structural diagram of a diagnostic circuit of another valve control circuit according to an embodiment of the present application, in this embodiment, as a preferred embodiment, a short circuit detection circuit includes a comparator U1 and a first resistor R1; the non-inverting input end of the comparator U1 is connected with the first end of the first resistor R1, the second end of the first resistor R1 is connected with the first end of the sampling resistor Rs, the inverting input end of the comparator U1 is connected with a reference power supply, and the output end of the comparator U1 serves as the output end of the short circuit detection circuit.
As shown in fig. 3, the short-circuit detection circuit is mainly composed of a comparator U1 and a first resistor R1. The comparator U1 is a device that compares an analog voltage signal with a reference voltage. The two inputs of the comparator U1 are analog signals, the output is binary signal 0 or 1, and when the difference value of the input voltage is increased or decreased and the positive and negative signs are unchanged, the output is kept constant. The primary function of the first resistor R1 is to limit current, preventing excessive current at the first end of the sampling resistor Rs from damaging the comparator U1. The non-inverting input end of the comparator U1 is connected with the first end of the first resistor R1, the second end of the first resistor R1 is connected with the first end of the sampling resistor Rs, and the inverting input end of the comparator U1 is connected with a reference power supply; during detection, the comparator U1 diagnoses the circuit condition from the first end of the sampling resistor Rs to the load resistor RL by comparing the voltage at the first end of the sampling resistor Rs with the reference voltage value output by the reference power supply, and outputs 1 or 0 to the interrupt pin of the MCU according to the diagnosis result.
It should be noted that the reference power supply needs to combine the voltage value at the non-inverting input end of the comparator U1 during normal operation of the circuit, adjust the reference voltage value to be equal to the former, and output to the inverting input end of the comparator U1, so as to ensure the detection function of the short circuit detection circuit; in this embodiment, the specific voltage adjustment manner of the reference power supply is not limited, and depends on the specific implementation.
In the embodiment, the short circuit detection circuit is composed of a first resistor and a comparator, and diagnosis of a rear load resistor circuit of the valve control circuit is realized by acquiring a voltage value of a first end of the sampling resistor and combining a reference voltage value output by a reference power supply; simple structure has the function of sending interrupt signal, and is very economical and has better diagnosis instantaneity.
In the above-described embodiment, there is no particular limitation on the specific structure of the voltage comparison circuit 11, depending on the specific implementation. In this embodiment, as a preferred embodiment, fig. 4 is a schematic diagram of a structure of a voltage comparing circuit 11 provided in the embodiment of the present application, and as shown in fig. 4, the voltage comparing circuit 11 includes a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, a first operational amplifier U2, a second operational amplifier U3, a third operational amplifier U4, and a first diode D1;
the output end of the first DAC10 is connected with the first end of the second resistor R2, and the second end of the second resistor R2 is connected with the first end of the third resistor R3 and the inverting input end of the first operational amplifier U2; the output end of the differential amplifier 12 is connected with the first end of a fourth resistor R4, the second end of the fourth resistor R4 is connected with the first end of a fifth resistor R5 and the non-inverting input end of the first operational amplifier U2, and the second end of the fifth resistor R5 is grounded; the output end of the first operational amplifier U2 is connected with the second end of the third resistor R3 and the first end of the sixth resistor R6, the second end of the sixth resistor R6 is connected with the first end of the seventh resistor R7 and the inverting input end of the second operational amplifier U3, the first end of the eighth resistor R8 is connected with the non-inverting input end of the second operational amplifier U3, and the second end of the eighth resistor R8 is grounded; the output end of the second operational amplifier U3 is connected with the anode of the first diode D1, and the cathode of the first diode D1 is connected with the second end of the seventh resistor R7 and the non-inverting input end of the third operational amplifier U4; the first end of the ninth resistor R9 is connected with the first end of the tenth resistor R10 and the inverting input end of the third operational amplifier U4, and the second end of the ninth resistor R9 is grounded; the second end of the tenth resistor R10 is connected with the output end of the third operational amplifier U4, and the output end of the third operational amplifier U4 is connected with the interrupt pin of the MCU; the first end of the second resistor R2 and the first end of the fourth resistor R4 are respectively input ends of the voltage comparison circuit 11, and the output end of the third operational amplifier U4 is an output end of the voltage comparison circuit 11.
In a specific implementation, the second resistor R2, the third resistor R3, the fourth resistor R4, the fifth resistor R5, the first operational amplifier U2 and the connection manner thereof together form a subtracting circuit. The first end of the second resistor R2 and the first end of the fourth resistor R4 are input ends of the voltage comparison circuit 11 respectively; specifically, a first end of the second resistor R2 is connected to the output end of the first DAC10, and a first end of the fourth resistor R4 is connected to the output end of the differential amplifier 12; according to the operating principle of the subtracting circuit, the voltage value at the output of the subtracting circuit is the difference between the voltage value at the first end of the second resistor R2 and the voltage value at the first end of the fourth resistor R4.
The sixth resistor R6, the seventh resistor R7, the eighth resistor R8, the second operational amplifier U3, the first diode D1 and their connection form an absolute value circuit together, so that the voltage value input into the absolute value circuit by the subtracting circuit becomes its absolute value. The third operational amplifier U4, the ninth resistor R9, the tenth resistor R10 and the connection mode thereof form an amplifying circuit together, the voltage value input into the amplifying circuit by the absolute value circuit is amplified, and finally the voltage value is output to the interrupt pin of the MCU.
In the embodiment, the three circuit parts are formed by the devices, and the voltage comparison circuit is formed by the three circuit parts together, so that the voltage comparison function is realized, and the device has a simple and reliable structure and is quite economical.
As shown in fig. 3, to further protect the valve control circuit from possible voltage surges, such as lightning strike, damaging the circuit, in this embodiment, a protection circuit is further included, which is disposed between the sampling resistor Rs and the load resistor RL; fig. 5 is a schematic structural diagram of a protection circuit provided in an embodiment of the present application, where, as shown in fig. 5, the protection circuit includes an eleventh resistor R11 and a second diode D2; the first end of the eleventh resistor R11 is connected with the first end of the sampling resistor Rs and the cathode of the second diode D2, and the second end of the eleventh resistor R11 is connected with the first end of the load resistor RL; the anode of the second diode D2 and the second terminal of the load resistor RL are grounded for setting the reference voltage value and the protection circuit.
It can be understood that the connection mode of the eleventh resistor R11 and the second diode D2 and the load resistor RL provides protection for the load resistor RL, when the line is suddenly increased by the lightning voltage, the resistance of the eleventh resistor R11 prevents the devices in the circuit from being burned out, and the second diode D2 directs the redundant voltage to the ground, so as to protect the circuit. The specific choice of the devices of the eleventh resistor R11 and the second diode D2 depends on the specific implementation, and is not limited herein. Meanwhile, since the eleventh resistor R11 is disposed between the sampling resistor Rs and the load resistor RL, the resistance value of the eleventh resistor R11 also affects the setting of the reference voltage value of the reference power supply output.
In the embodiment, the protection circuit is added between the sampling resistor and the load resistor, the reference voltage value is set, meanwhile, the circuit is prevented from being damaged under the condition of voltage surge such as lightning stroke, and the circuit is effectively protected.
In the above embodiment, there is no limitation in the device selection of the eleventh resistor R11 and the second diode D2, depending on the specific implementation. In this embodiment, as a preferred embodiment, the eleventh resistor R11 is a positive temperature coefficient thermistor, and the second diode D2 is a transient diode.
It can be appreciated that a transient diode is an efficient circuit protection device that does not conduct when the line is operating properly; when the line is struck by lightning, the voltage value in the line is extremely high, the two poles of the transient diode are impacted by reverse transient high energy, the high resistance between the two poles is changed into low resistance, the energy is led into the ground, and the voltage in the line is clamped in a safe range; effectively protecting the devices in the circuit. The positive temperature coefficient thermistor selected by the eleventh resistor R11 is characterized in that the current is increased when the transient diode is conducted, the line temperature is increased, the resistance of the positive temperature coefficient thermistor is increased along with the temperature increase, and the transient diode is prevented from being burnt; meanwhile, when the circuit works normally, the positive temperature coefficient thermistor is in a normal temperature state, and the resistance value is small, so that the normal work of the circuit is not affected.
In the embodiment, the transient diode and the positive temperature coefficient thermistor are selected to form a protection circuit together, so that the circuit is effectively protected from being damaged when being struck by lightning.
In the above embodiment, the MCU outputs different voltage values as required by configuring the registers inside the DAC through the digital interface with the channel DAC, and at the same time, the MCU outputs the same data to the first DAC10 and configures it to output the same voltage value as the channel DAC. In this embodiment, the first DAC10 and the MCU are connected using a serial peripheral interface (Serial Peripheral Interface, SPI) bus.
It can be appreciated that the SPI bus is a high-speed full duplex synchronous communication bus and occupies only four wires on the pins of the chip; therefore, in this embodiment, the bus is selected to connect the MCU and the first DAC10, which saves pins of the chip, saves space on the layout of the PCB, and provides convenience.
Finally, the embodiment of the application also provides a valve control circuit. The valve control circuit comprises the diagnostic circuit of the valve control circuit mentioned above. Since the above description is made in detail for each component in the diagnostic circuit of the valve control circuit, the description of this embodiment is omitted.
The valve control circuit provided by the embodiment comprises a diagnosis circuit of the valve control circuit; the circuit comprises a first DAC, a voltage comparison circuit, a sampling resistor and a differential amplifier; the first DAC is connected with an MCU in the valve control circuit and is used for converting data transmitted by the MCU to obtain a first voltage value; the differential amplifier is connected with the sampling resistor and is used for amplifying the voltage value of the sampling resistor to obtain a second voltage value; the input end of the voltage comparison circuit is respectively connected with the first DAC and the differential amplifier and is used for determining a diagnosis result according to the first voltage value and the second voltage value; the output end of the voltage comparison circuit is connected with the interrupt pin of the MCU. The circuit diagnoses the channel of the valve control circuit in real time through the voltage comparison circuit, and simultaneously outputs a diagnosis result in an interrupt triggering mode, thereby having better instantaneity.
The above description is provided in detail for a valve control circuit and a diagnostic circuit for a valve control circuit. In the description, each embodiment is described in a progressive manner, and each embodiment is mainly described by the differences from other embodiments, so that the same similar parts among the embodiments are mutually referred. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant points refer to the description of the method section. It should be noted that it would be obvious to those skilled in the art that various improvements and modifications can be made to the present application without departing from the principles of the present application, and such improvements and modifications fall within the scope of the claims of the present application.
It should also be noted that in this specification, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
Claims (8)
1. A diagnostic circuit for a valve control circuit, comprising: a first DAC (10), a voltage comparison circuit (11), a sampling resistor and a differential amplifier (12);
the first DAC (10) is connected with an MCU in the valve control circuit and is used for converting data transmitted by the MCU to obtain a first voltage value; the differential amplifier (12) is connected with the sampling resistor and is used for amplifying the voltage value of the sampling resistor to obtain a second voltage value; the input end of the voltage comparison circuit (11) is respectively connected with the first DAC (10) and the differential amplifier (12) and is used for determining a diagnosis result according to the first voltage value and the second voltage value;
the output end of the voltage comparison circuit (11) is connected with the interrupt pin of the MCU;
the circuit also comprises a short circuit detection circuit;
the input end of the short circuit detection circuit is respectively connected with the first end of the sampling resistor and the output end of the reference power supply, and is used for determining a diagnosis result according to the third voltage value of the first end of the sampling resistor and the reference voltage value output by the reference power supply; and the output end of the short circuit detection circuit is connected with the interrupt pin of the MCU.
2. The diagnostic circuit of claim 1 wherein the short circuit detection circuit comprises a comparator and a first resistor;
the non-inverting input end of the comparator is connected with the first end of the first resistor, the second end of the first resistor is connected with the first end of the sampling resistor, the inverting input end of the comparator is connected with a reference power supply, and the output end of the comparator is used as the output end of the short circuit detection circuit.
3. The diagnostic circuit of a valve control circuit according to claim 1, wherein the voltage comparison circuit (11) comprises a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, a first operational amplifier, a second operational amplifier, a third operational amplifier, and a first diode;
the output end of the first DAC (10) is connected with the first end of the second resistor, and the second end of the second resistor is connected with the first end of the third resistor and the inverting input end of the first operational amplifier; the output end of the differential amplifier (12) is connected with the first end of the fourth resistor, the second end of the fourth resistor is connected with the first end of the fifth resistor and the non-inverting input end of the first operational amplifier, and the second end of the fifth resistor is grounded; the output end of the first operational amplifier is connected with the second end of the third resistor and the first end of the sixth resistor, the second end of the sixth resistor is connected with the first end of the seventh resistor and the inverting input end of the second operational amplifier, the first end of the eighth resistor is connected with the non-inverting input end of the second operational amplifier, and the second end of the eighth resistor is grounded; the output end of the second operational amplifier is connected with the anode of the first diode, and the cathode of the first diode is connected with the second end of the seventh resistor and the non-inverting input end of the third operational amplifier; the first end of the ninth resistor is connected with the first end of the tenth resistor and the inverting input end of the third operational amplifier, and the second end of the ninth resistor is grounded; the second end of the tenth resistor is connected with the output end of the third operational amplifier, and the output end of the third operational amplifier is connected with the interrupt pin of the MCU;
the first end of the second resistor and the first end of the fourth resistor are respectively input ends of the voltage comparison circuit (11), and the output end of the third operational amplifier is an output end of the voltage comparison circuit (11).
4. The diagnostic circuit of a valve control circuit of claim 1, further comprising a guard circuit comprising an eleventh resistor and a second diode;
the first end of the eleventh resistor is connected with the first end of the sampling resistor and the cathode of the second diode, and the second end of the eleventh resistor is connected with the first end of the load resistor; and the anode of the second diode and the second end of the load resistor are grounded and are used for setting the reference voltage value and the protection circuit.
5. The diagnostic circuit of claim 4 wherein the eleventh resistor is a positive temperature coefficient thermistor.
6. The diagnostic circuit of claim 4 wherein the second diode is a transient diode.
7. The diagnostic circuit of a valve control circuit according to claim 1, characterized in that the first DAC (10) is connected to the MCU using an SPI bus.
8. A valve control circuit comprising a diagnostic circuit of the valve control circuit of any one of claims 1 to 7.
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| CN202111259099.3A CN113885479B (en) | 2021-10-27 | 2021-10-27 | Valve control circuit and diagnostic circuit thereof |
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| CN202111259099.3A CN113885479B (en) | 2021-10-27 | 2021-10-27 | Valve control circuit and diagnostic circuit thereof |
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| CN113885479B true CN113885479B (en) | 2024-03-01 |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202421808U (en) * | 2012-01-12 | 2012-09-05 | 孙得膑 | Intelligent power system for primary and secondary clocks |
| CN202421279U (en) * | 2011-12-13 | 2012-09-05 | 常熟开关制造有限公司(原常熟开关厂） | Voltage and frequency measuring circuit for breaker |
| JP2014143537A (en) * | 2013-01-23 | 2014-08-07 | Yamaha Corp | Load current detection circuit |
| CN104661170A (en) * | 2015-03-09 | 2015-05-27 | 山东省计算中心（国家超级计算济南中心） | Fault detection system for multiple speakers |
| CN209167876U (en) * | 2019-01-15 | 2019-07-26 | 长沙硕博电子科技股份有限公司 | A kind of Proportion valve controlling circuit |
| CN113110397A (en) * | 2021-05-08 | 2021-07-13 | 重庆红江机械有限责任公司 | High-speed electromagnetic valve driving circuit and fault diagnosis circuit and method |
-
2021
- 2021-10-27 CN CN202111259099.3A patent/CN113885479B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202421279U (en) * | 2011-12-13 | 2012-09-05 | 常熟开关制造有限公司(原常熟开关厂） | Voltage and frequency measuring circuit for breaker |
| CN202421808U (en) * | 2012-01-12 | 2012-09-05 | 孙得膑 | Intelligent power system for primary and secondary clocks |
| JP2014143537A (en) * | 2013-01-23 | 2014-08-07 | Yamaha Corp | Load current detection circuit |
| CN104661170A (en) * | 2015-03-09 | 2015-05-27 | 山东省计算中心（国家超级计算济南中心） | Fault detection system for multiple speakers |
| CN209167876U (en) * | 2019-01-15 | 2019-07-26 | 长沙硕博电子科技股份有限公司 | A kind of Proportion valve controlling circuit |
| CN113110397A (en) * | 2021-05-08 | 2021-07-13 | 重庆红江机械有限责任公司 | High-speed electromagnetic valve driving circuit and fault diagnosis circuit and method |
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| CN113885479A (en) | 2022-01-04 |
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