Signal deviation display circuit and device for nuclear power plant

Abstract

The utility model relates to a signal deviation display circuit and device for a nuclear power plant, and the circuit comprises a differential amplification unit which is used for accessing an analog signal and carrying out the amplification and filtering processing of the analog signal, so as to form a signal after difference point processing; the conversion unit is connected with the differential amplification unit and is used for receiving the signal subjected to differential processing and converting the signal subjected to differential processing into a digital signal; the processing unit is connected with the conversion unit and is used for receiving the digital signal and outputting signal deviation information of the analog signal and an alarm control instruction; the display unit is connected with the processing unit and is used for receiving the signal deviation information and displaying the signal deviation information; and the alarm unit is connected with the processing unit and is used for receiving the alarm control instruction and outputting an alarm signal. According to the utility model, drift and noise signals in analog signals can be effectively suppressed, the precision of the analog signals is improved, and the technical effect of accurately displaying analog signal deviation is realized.

Description

TECHNICAL FIELD

[0001] The utility model relates to nuclear power plant equipment technical field especially relates to a nuclear power plant signal deviation display circuit and device. BACKGROUND

[0002] Some nuclear power plants because of the early construction time, part analog signal detection related device because because design time is earlier, there is serious precision drift, lead to analog signal credibility reduction, influence nuclear power plant's security. And the service life is longer, the device has the aging problem, faces the situation of large area replacement, part device has stopped production, therefore nuclear power plant urgently needs a kind of technical scheme that can accurately display analog signal deviation. UTILITY MODEL CONTENT

[0003] The utility model solves the technical problem in at, provide a nuclear power plant signal deviation display circuit and device.

[0004] The utility model solves the technical problem and adopts the technical scheme that: constructs a kind of nuclear power plant signal deviation display circuit, comprising:

[0005] Differential amplification unit is used to access analog signal and amplify and filter process to form differential processing signal to the analog signal;

[0006] Conversion unit is connected with the differential amplification unit, is used to receive the differential processing signal and converts the differential processing signal into digital signal;

[0007] Processing unit is connected with the conversion unit, is used to receive the digital signal and output the signal deviation information and alarm control instruction of the analog signal;

[0008] Display unit is connected with the processing unit, is used to receive the signal deviation information and display the signal deviation information;And

[0009] Alarm unit is connected with the processing unit, is used to receive the alarm control instruction and output alarm signal.

[0010] Preferably, the differential amplification unit includes:

[0011] Voltage division and impedance conversion unit is used to access the analog signal to the analog signal voltage division, and the input impedance conversion to form the converted signal to the analog signal after voltage division;And

[0012] Signal amplification unit is connected with the voltage division and impedance conversion unit and the conversion unit, is used to receive the converted signal and amplify the converted signal to form the differential processing signal.

[0013] Preferably, the voltage dividing and impedance converting unit comprises a first operational amplifier integrated circuit U16, a first resistor R42, a second resistor R43, a third resistor R44 and a fourth resistor R51; wherein the first operational amplifier integrated circuit U16 comprises a first operational amplifier and a second operational amplifier.

[0014] A first end of the first resistor R42 is connected to the analog signal, a second end of the first resistor R42 is connected to a non-inverting input terminal of the first operational amplifier and to the ground through the second resistor R43, an inverting input terminal and an output terminal of the first operational amplifier are connected and connected to an inverting input terminal of the second operational amplifier through the third resistor R44, the inverting input terminal of the second operational amplifier is also connected to the output terminal of the second operational amplifier and the signal amplifying unit through the fourth resistor R51, and a non-inverting input terminal of the second operational amplifier is connected to the ground.

[0015] Preferably, the signal amplifying unit comprises a second operational amplifier integrated circuit U17, a fifth resistor R45, a sixth resistor R46, a seventh resistor R47 and an eighth resistor R48; wherein the second operational amplifier integrated circuit U17 comprises a third operational amplifier.

[0016] An inverting input terminal of the third operational amplifier is connected to the voltage dividing and impedance converting unit through the fifth resistor R45 and connected to the output terminal of the third operational amplifier through the sixth resistor R46, a non-inverting input terminal of the third operational amplifier is connected to a first direct current voltage through the seventh resistor R47 and connected to the ground through the eighth resistor R48, and the output terminal of the third operational amplifier is also connected to the converting unit.

[0017] Preferably, the converting unit comprises:

[0018] an analog-to-digital converting unit connected to the differential amplifying unit, for receiving the differential processed signal and converting the differential processed signal into a digital signal; and

[0019] a communication level converting unit connected between the analog-to-digital converting unit and the processing unit, for receiving the digital signal and isolating the digital signal.

[0020] Preferably, the display unit comprises:

[0021] a nixie tube driving unit connected to the processing unit, for receiving a display instruction output by the processing unit; and

[0022] a nixie tube unit connected to the nixie tube driving unit, for receiving the display instruction and displaying the signal deviation information.

[0023] Preferably, the nuclear power plant signal deviation display circuit further comprises:

[0024] The key unit is connected with the processing unit, and is configured to output a threshold setting instruction capable of setting the upper threshold and the lower threshold and a display control instruction capable of controlling the display unit to display content according to operation;

[0025] The alarm indication unit is connected with the processing unit, and is configured to output an indication signal when the analog signal is greater than the upper threshold or the analog signal is less than the lower threshold.

[0026] Preferably, the alarm unit comprises:

[0027] The upper limit alarm unit is connected with the processing unit, and is configured to output an upper limit alarm signal when the analog signal is greater than the upper threshold; and

[0028] The lower limit alarm unit is connected with the processing unit, and is configured to output an upper limit alarm signal when the analog signal is less than the lower threshold.

[0029] Preferably, the upper limit alarm unit and the lower limit alarm unit respectively comprise a relay K5, a switch tube Q1, a twelfth resistor R4 and a thirteenth resistor R6; a first end of an exciting coil of the relay K5 is connected with a fourth direct current voltage, and a second end is connected with an input end of the switch tube Q1, a control end of the switch tube Q1 is connected to the processing unit through the twelfth resistor R4 in one way, and is connected to an output end of the switch tube Q1 and the ground through the thirteenth resistor R6 in another way, and common contacts and normally open contacts of the relay K5 are used for connecting an alarm.

[0030] The utility model also constructs a kind of nuclear power plant signal deviation display device, including the nuclear power plant signal deviation display circuit described above.

[0031] The utility model has the following beneficial effects: the drift in analog signal and noise signal can be effectively inhibited, the precision of analog signal is improved, and the technical effect of accurately displaying analog signal deviation is realized, which plays a positive role in improving the safety of nuclear power plant. BRIEF DESCRIPTION OF DRAWINGS

[0032] The utility model will be further described below in conjunction with drawings and examples, and in the drawings:

[0033] Figure 1 It is the circuit structure block diagram of the nuclear power plant signal deviation display circuit in an embodiment of the utility model;

[0034] Figure 2 It is the circuit principle diagram of differential amplification unit in an embodiment of the utility model;

[0035] Figure 3Is the circuit schematic of the analog-digital conversion unit in an embodiment of the utility model;

[0036] Figure 4 Is the circuit schematic of the communication level conversion unit in an embodiment of the utility model;

[0037] Figure 5 Is the circuit schematic of the nixie tube driving unit in an embodiment of the utility model;

[0038] Figure 6 Is the circuit schematic of the nixie tube unit in an embodiment of the utility model;

[0039] Figure 7 Is the circuit schematic of the alarm unit in an embodiment of the utility model;

[0040] Figure 8 Is the circuit schematic of the key unit in an embodiment of the utility model;

[0041] Figure 9 Is the circuit schematic of the alarm indication unit in an embodiment of the utility model;

[0042] Figure 10 Is the circuit schematic of the direct current voltage conversion unit in an embodiment of the utility model;

[0043] Figure 11 Is the circuit schematic of the positive and negative voltage conversion unit in an embodiment of the utility model;

[0044] Figure 12 Is the circuit schematic of the reference voltage unit in an embodiment of the utility model;

[0045] Figure 13 Is the curve graph of the analog signal measurement value and error value after the analog signal of the utility model is processed. DETAILED DESCRIPTION

[0046] In order to have a more clear understanding of the technical features, purposes and effects of the utility model, the specific implementation mode of the utility model will be explained in detail by referring to the drawings.

[0047] In the following description, it is understood that the orientation or position relationship of "front", "back", "upper", "lower", "left", "right", "vertical", "horizontal", "vertical", "horizontal", "top", "bottom", "inner", "outer", "head", "tail" and the like is based on the orientation or position relationship shown in the drawings, constructed and operated in a particular orientation, and is only for the convenience of describing the technical scheme, and cannot be understood as indicating that the indicated device or element must have a particular orientation, therefore, it cannot be understood as a limitation on the utility model.

[0048] The utility model provides a nuclear power plant signal deviation display circuit, this nuclear power plant signal deviation display circuit can access nuclear power plant all kinds of instrument analog signal, such as throttle opening, steam turbine speed, pressure, temperature etc.

[0049] Figure 1 It is the circuit structure block diagram of nuclear power plant signal deviation display circuit in an embodiment of the utility model, please refer to Figure 1 , this nuclear power plant signal deviation display circuit can include differential amplification unit 1, conversion unit 2, processing unit 3, display unit 4 and alarm unit 5.

[0050] Differential amplification unit 1 is used to access analog signal to amplify and filter processing to the analog signal to form difference point processing signal. Differential amplification unit 1 can amplify the voltage amplitude of analog signal to facilitate accurate detection of the subsequent circuit, and has significant common mode rejection performance, can suppress the drift and noise signal superimposed in analog signal, and further improve the signal-to-noise ratio of analog signal.

[0051] Figure 2 It is the circuit principle diagram of differential amplification unit in an embodiment of the utility model, as Figure 2 Indicated, differential amplification unit 1 can include voltage division and impedance conversion unit 11 and signal amplification unit 12.

[0052] Voltage division and impedance conversion unit 11 is used to access analog signal, carries out voltage division to analog signal, and carries out input impedance conversion to the analog signal after voltage division to form conversion signal. Voltage division to analog signal is to make the voltage amplitude of analog signal reduce in proportion, helps to filter out part of noise, carries out input impedance conversion to the analog signal after voltage division to help improve signal integrity and stability, and further filter out drift and noise signal.

[0053] In some embodiments, as Figure 2As shown, the voltage division and impedance conversion unit 11 can include a first operational amplifier integrated circuit U16, a first resistor R42, a second resistor R43, a third resistor R44, and a fourth resistor R51. The first operational amplifier integrated circuit U16 includes a first operational amplifier and a second operational amplifier, and the first operational amplifier integrated circuit U16 can be an existing dual operational amplifier integrated circuit, such as a model TLC27M2MD dual operational amplifier. A first end of the first resistor R42 is connected to the analog signal, a second end of the first resistor R42 is connected to a non-inverting input terminal (corresponding to a third pin of the first operational amplifier integrated circuit U16) of the first operational amplifier via the second resistor R43 and to ground, and an inverting input terminal (corresponding to a second pin of the first operational amplifier integrated circuit U16) and an output terminal (corresponding to a first pin of the first operational amplifier integrated circuit U16) of the first operational amplifier are connected and then connected to an inverting input terminal (corresponding to a sixth pin of the first operational amplifier integrated circuit U16) of the second operational amplifier via the third resistor R44. The inverting input terminal of the second operational amplifier is also connected to an output terminal (corresponding to a seventh pin of the first operational amplifier integrated circuit U16) of the second operational amplifier and the signal amplification unit 12 via the fourth resistor R51, and a non-inverting input terminal (corresponding to a fifth pin of the first operational amplifier integrated circuit U16) of the second operational amplifier is connected to ground.

[0054] As shown in FIG. 4, Figure 2 The working principle of the voltage division and impedance conversion unit 11 is as follows: the first resistor R42 and the second resistor R43 form a voltage division circuit that can divide the voltage amplitude of the analog signal, and output the divided analog signal at a first end of the first resistor R42; the first operational amplifier and the third resistor R44 form a first voltage follower that can isolate signals to reduce noise interference between the front and rear stages; the second operational amplifier and the fourth resistor R51 form a second voltage follower that can increase the input impedance of the divided analog signal and reduce the output impedance of the divided analog signal to achieve impedance conversion, and can control the common-mode rejection ratio by adjusting the resistance value of the fourth resistor R51 to improve the performance of suppressing drift signals and noise signals.

[0055] Further, in order to further improve the filtering effect of the voltage division and impedance conversion unit 11, in some embodiments, as shown in FIG. 5, Figure 2 The voltage division and impedance conversion unit 11 can further include a first capacitor C43. The non-inverting input terminal of the first operational amplifier is connected to ground via the first capacitor C43, and the first capacitor C43 can filter out noise and interference in the divided analog signal.

[0056] As shown in FIG. 6, Figure 2As shown, the signal amplification unit 12 is connected with the voltage division and impedance conversion unit 11 and the conversion unit 2, and is configured to receive the converted signal and amplify the converted signal to form the differential processed signal and input the differential processed signal to the conversion unit 2. It can be understood that, under the action of the voltage division and impedance conversion unit 11, most of the drift signals and noise signals in the analog signal have been filtered, that is, the impedance-converted analog signal can be regarded as an effective signal, and the signal amplification unit 12 can amplify the voltage amplitude of the effective signal, so that the voltage amplitude of the effective signal can be more accurately detected by the subsequent circuit, and the collection accuracy is improved.

[0057] In some embodiments, as Figure 2 As shown, the signal amplification unit 12 includes a second operational amplifier integrated circuit U17, a fifth resistor R45, a sixth resistor R46, a seventh resistor R47, and an eighth resistor R48; the second operational amplifier integrated circuit U17 includes a third operational amplifier.

[0058] The inverting input end of the third operational amplifier (corresponding to the second pin of the second operational amplifier integrated circuit U17) is connected to the output end of the second operational amplifier of the voltage division and impedance conversion unit 11 through the fifth resistor R45, and is connected to the output end of the third operational amplifier (corresponding to the first pin of the second operational amplifier integrated circuit U17) through the sixth resistor R46; the non-inverting input end of the third operational amplifier (corresponding to the third pin of the second operational amplifier integrated circuit U17) is connected to the first direct current voltage (corresponding to VREF_1.25V) through the seventh resistor R47, and is connected to the ground through the eighth resistor R48; and the output end of the third operational amplifier (corresponding to the first pin of the second operational amplifier integrated circuit U17) is also connected to the conversion unit 2 to input the amplified analog signal to the conversion unit 2.

[0059] Please refer to Figure 2 The working principle of the signal amplification unit 12 is as follows: the second operational amplifier integrated circuit U17, the fifth resistor R45, the sixth resistor R46, the seventh resistor R47, and the eighth resistor R48 form a differential amplification circuit capable of amplifying the voltage amplitude of the impedance-converted analog signal, and the gain of the differential amplification circuit can be set by adjusting the resistance values of the fifth resistor R45, the sixth resistor R46, the seventh resistor R47, and the eighth resistor R48.

[0060] In some embodiments, as Figure 2As shown, the signal amplification unit 12 further comprises a ninth resistor R49 and a tenth resistor R50. Correspondingly, the second operational amplifier integrated circuit U17 further comprises a fourth operational amplifier, which can be a conventional dual operational amplifier integrated circuit, such as a dual operational amplifier with a model number TLC27M2MD. The non-inverting input terminal of the fourth operational amplifier (corresponding to the 5th pin of the second operational amplifier integrated circuit U17) is connected to the ground via the ninth resistor R49 and connected to the second DC voltage (corresponding to VREF_2.5V) via the tenth resistor R50. The inverting input terminal of the fourth operational amplifier is connected to the output terminal, which serves as the first DC voltage output terminal to provide the first DC voltage to the seventh resistor R47.

[0061] As shown in FIG. 1, the differential amplification unit 1 is connected to the processing unit 3. Figure 1 As shown, the conversion unit 2 is connected to the differential amplification unit 1, and the conversion unit 2 is configured to receive the differential processed signal and convert the differential processed signal into a digital signal.

[0062] Figure 3 FIG. 1 is a circuit schematic diagram of the analog-to-digital conversion unit in an embodiment of the present application. Figure 4 FIG. 1 is a circuit schematic diagram of the analog-to-digital conversion unit in an embodiment of the present application. Figure 3 As shown in FIG. 1, the differential amplification unit 1 is connected to the processing unit 3. Figure 4 As shown in FIG. 1, the differential amplification unit 1 is connected to the processing unit 3.

[0063] The analog-to-digital conversion unit 21 is connected to the differential amplification unit 1, and the analog-to-digital conversion unit 21 is configured to receive the differential processed signal and convert the differential processed signal into a digital signal. Since the processing unit 3 cannot directly detect the analog signal, it is necessary to convert the amplified analog signal level into a digital signal.

[0064] As shown in FIG. 1, the differential amplification unit 1 is connected to the processing unit 3. Figure 3 and Figure 4 As shown in FIG. 1, the differential amplification unit 1 is connected to the processing unit 3.

[0065] The communication level conversion unit 22 is connected between the analog-digital conversion unit 21 and the processing unit 3, and is configured to receive the digital signal and isolate the digital signal, and input the isolated signal to the processing unit 3. Since the communication logic level of the analog-digital conversion unit 21 is 5V, and the communication logic voltage of the processing unit 3 is 3.3V, the communication logic levels of the two are not matched, and direct communication is not possible, and therefore the communication level conversion unit 22 is needed to realize level conversion.

[0066] In some embodiments, as shown in Figure 3 and Figure 4 The communication level conversion unit 22 can include a level shifter U4, a third capacitor C23, a fourteenth resistor R9, and a fourth capacitor C24. The A-side power supply end (corresponding to the 2nd pin of the level shifter U4) of the level shifter U4 is connected to the third DC voltage (VCC_3.3V) and to ground through the third capacitor C23, the enable end (corresponding to the 10th pin of the level shifter U4) of the level shifter U4 is connected to the first power supply end of the level shifter U4 through the fourteenth resistor R9, the second A-side input / output end to the sixth A-side input / output end (corresponding to the 3rd to 7th pins of the level shifter U4, respectively) of the level shifter U4 are connected to the processing unit 3, the B-side power supply end (corresponding to the 19th pin of the level shifter U4) of the level shifter U4 is connected to the fourth DC voltage (VCC_5V) and to ground through the fourth capacitor C24, and the second B-side input / output end to the sixth B-side input / output end (corresponding to the 18th, 17th, 16th, 15th, and 14th pins of the level shifter U4, respectively) of the level shifter U4 are connected to the communication end of the analog-digital converter U12. The level shifter U4 can be an existing level shifter, such as a level shifter with model number TXS0108EPWR. In this embodiment, under the pull-up action of the fourteenth resistor R9, the levels of the second to sixth A-side input / output ends of the level shifter U4 correspond to the second to sixth B-side input / output ends of the level shifter U4, respectively, so that when the second B-side input / output end is at a high level, the second A-side input / output end is also at a high level.

[0067] As shown in Figure 1The processing unit 3 is connected with the conversion unit 2, and the processing unit 3 is used for receiving the digital signal and outputting the signal deviation information of the analog signal and the alarm control instruction according to the digital signal. Specifically, after receiving the digital signal, the processing unit 3 determines the size of the analog signal based on the digital signal, and then compares the analog signal with the preset upper threshold and lower threshold to determine whether the analog signal is greater than the upper threshold or less than the lower threshold. When the analog signal is greater than the upper threshold or less than the lower threshold, it is determined that the deviation of the analog signal is abnormal, and the alarm control instruction is output to the alarm unit 5. It should be noted that the comparison algorithm of the analog signal and the upper threshold and the lower threshold belongs to a conventional algorithm, and specific reference can be made to the existing algorithm. In addition, the signal deviation information can be the analog signal, the upper threshold or the lower threshold.

[0068] In some embodiments, the processing unit 3 can include a microprocessor of the STM32 series and a linear power supply connected with the microprocessor. The linear power supply can include a linear voltage regulator with a model number of AMS1117-3.3, and the linear power supply can provide a power supply of 3.3V for the microprocessor.

[0069] As shown in Figure 1 The display unit 4 is connected with the processing unit 3, and the display unit 4 is used for displaying the signal deviation information.

[0070] Figure 5 is a circuit principle diagram of the nixie tube driving unit in an embodiment of the utility model. Figure 6 is a circuit principle diagram of the nixie tube unit in an embodiment of the utility model. In some embodiments, the display unit 4 can include a nixie tube driving unit 41 as shown in Figure 5 and a nixie tube unit 42 as shown in Figure 6 .

[0071] The nixie tube driving unit 41 is connected with the processing unit 3, and the nixie tube driving unit 41 is used for receiving the display instruction output by the processing unit 3, and then controlling the nixie tube unit 42 to work according to the display instruction, so that the nixie tube unit 42 displays the analog signal, the upper threshold or the lower threshold (i.e. the signal deviation information).

[0072] In some embodiments, as shown in Figure 5As shown, the nixie tube driving unit 41 can include a nixie tube driver U3 and a fifteenth resistor R1. The data input end of the nixie tube driver U3 (corresponding to the 16th pin of the nixie tube driver U3) is connected to the processing unit 3 through the fifteenth resistor R1, the segment / bit multiplexing end of the nixie tube driver U3 (corresponding to the 9th pin of the nixie tube driver U3) is connected to the processing unit 3, and the segment output end (including the 2nd to 8th pins of the nixie tube driver U3) and the bit output end (including the 11th to 14th pins of the nixie tube driver U3) of the nixie tube driver U3 are connected to the nixie tube unit 42. The nixie tube driver U3 can be a nixie tube driver of model TM1652.

[0073] The nixie tube unit 42 is connected to the nixie tube driving unit 41, and the nixie tube unit 42 is configured to receive a display instruction and display the signal deviation information according to the display instruction.

[0074] In some embodiments, as shown in Figure 5 and Figure 6 As shown, the nixie tube unit 42 can include two 2-bit nixie tubes U1. The 1st and 5th pins of each 2-bit nixie tube U1 are connected to the 6th pin of the nixie tube driver U3, the 2nd and 6th pins of each 2-bit nixie tube U1 are connected to the 5th pin of the nixie tube driver U3, the 3rd and 8th pins of each 2-bit nixie tube U1 are connected to the 4th pin of the nixie tube driver U3, the 4th and 9th pins of each 2-bit nixie tube U1 are connected to the 9th pin of the nixie tube driver U3, the 7th and 17th pins of each 2-bit nixie tube U1 are connected to the 8th pin of the nixie tube driver U3, the 10th and 15th pins of each 2-bit nixie tube U1 are connected to the 3rd pin of the nixie tube driver U3, the 11th and 16th pins of each 2-bit nixie tube U1 are connected to the 2nd pin of the nixie tube driver U3, the 12th and 18th pins of each 2-bit nixie tube U1 are connected to the 7th pin of the nixie tube driver U3, the 13th and 14th pins of one 2-bit nixie tube U1 are connected to the 14th and 15th pins of the nixie tube driver U3, respectively, and the 13th and 14th pins of the other 2-bit nixie tube U1 are connected to the 12th and 13th pins of the nixie tube driver U3, respectively. The 2-bit nixie tube U1 can be a 2-bit nixie tube of model HDSP-521E. It should be noted that the nixie tube driving unit 41 will control the segment selection and bit selection of the 2-bit nixie tube U1 in turn through dynamic scanning under the control of the processing unit 3, and the afterglow of the LED tube and the visual persistence of the human eye are used to make people feel that each bit nixie tube is displayed at the same time. For details, please refer to the prior art, which will not be described here.

[0075] As shown in Figure 1As shown, alarm unit 5 is connected to processing unit 3. Alarm unit 5 is used to receive alarm control commands and output alarm signals. Specifically, alarm unit 5 outputs an alarm signal when it receives an alarm control command.

[0076] Figure 7 This is a circuit diagram of the alarm unit in one embodiment of the present invention. In some embodiments, the alarm unit 5 may include, for example: Figure 7 The upper limit alarm unit 51 and the lower limit alarm unit 52 are shown.

[0077] The upper limit alarm unit 51 is connected to the processing unit 3. The upper limit alarm unit 51 is used to output an upper limit alarm signal when the analog signal is greater than the upper limit threshold. Specifically, when the processing unit 3 determines that the analog signal is greater than the upper limit threshold, it controls the upper limit alarm unit 51 to output the upper limit alarm signal.

[0078] The lower limit alarm unit 52 is connected to the processing unit 3. The lower limit alarm unit 52 is used to output an upper limit alarm signal when the analog signal is less than the lower limit threshold. Specifically, when the processing unit 3 determines that the analog signal is greater than the upper limit threshold, it controls the upper limit alarm unit 51 to output an upper limit alarm signal.

[0079] In some embodiments, such as Figure 7 As shown, the upper limit alarm unit 51 and the lower limit alarm unit 52 may each include a relay K5, a switching transistor Q1, a twelfth resistor R4, and a thirteenth resistor R6. The excitation coil of relay K5 has its first terminal connected to a fourth DC voltage and its second terminal connected to the input terminal of switching transistor Q1. The control terminal of switching transistor Q1 is connected to the processing unit 3 via the twelfth resistor R4 and to the output terminal and ground via the thirteenth resistor R6. The common contact and normally open contact of relay K5 are used to connect to the alarm. Switching transistor Q1 can be a transistor or a MOSFET. In this embodiment, switching transistor Q1 is an NPN transistor, and its input, control, and output terminals correspond to the collector, base, and emitter of the NPN transistor, respectively.

[0080] Please see Figure 7, the working principle of the alarm unit 5 is as follows: when the processing unit 3 determines that the analog signal is greater than the upper limit threshold, a high level is output to the twelfth resistor R4 included in the upper limit alarm unit 51, so that the switch tube Q1 included in the upper limit alarm unit 51 is turned on, the common contact and the normally open contact of the relay K5 included in the upper limit alarm unit 51 are closed, and then a dry contact signal is output to the upper limit alarm to make the upper limit alarm work; when the processing unit 3 determines that the analog signal is less than the lower limit threshold, a high level is output to the twelfth resistor R4 included in the lower limit alarm unit 52, so that the switch tube Q1 included in the lower limit alarm unit 52 is turned on, the common contact and the normally open contact of the relay K5 included in the lower limit alarm unit 52 are closed, and then a dry contact signal is output to the lower limit alarm to make the lower limit alarm work. Wherein, the upper limit alarm and the lower limit alarm can be existing sound and light alarms or buzzers.

[0081] In some embodiments, as shown in Figure 7 , the upper limit alarm unit 51 and the lower limit alarm unit 52 can respectively include a diode D3. The cathode of the diode D3 is connected to the first end of the excitation coil of the relay K5, and the anode of the diode D3 is connected to the second end of the excitation coil of the relay K5. The diode D3 releases the energy output by the excitation coil of the relay K5 after power-off, and protects the relay K5.

[0082] In some embodiments, as shown in Figure 7 , the upper limit alarm unit 51 and the lower limit alarm unit 52 can respectively include a first LED lamp D1 and a sixteenth resistor R2. The anode of the first LED lamp D1 is connected to the first end of the excitation coil of the relay K5, and the cathode of the first LED lamp D1 is connected to the second end of the excitation coil of the relay K5 through the sixteenth resistor R2. It can be understood that the first LED lamp D1 is used to light up when the excitation coil of the relay K5 is excited, to show whether the switch tube Q1 is turned on.

[0083] In some embodiments, as shown in Figure 1 , the nuclear power plant signal deviation display circuit can further include a key unit 6.

[0084] The key unit 6 is connected with the processing unit 3, and the key unit 6 is used to output threshold setting instructions capable of setting the upper limit threshold and the lower limit threshold and display control instructions capable of controlling the display unit 4 to display content according to operation.

[0085] Figure 8 is the circuit principle diagram of the key unit in an embodiment of the utility model. In some embodiments, as shown in Figure 8As shown, the key unit 6 can include a plurality of keys, each of which is connected to the processing unit 3 respectively, so that the staff can input the threshold setting instruction or the display control instruction to the processing unit 3 by operating the corresponding key. Specifically, the number of keys can be 4, including the key K1, the key K2, the key K3 and the key K4. The operating principle of the key unit 6 can be: pressing the key K1 can control the display unit 4 to display the upper limit threshold, and after releasing the key K1, the display unit 4 displays the analog signal, which can help the staff to observe the deviation between the upper limit threshold and the analog signal; pressing the key K2 can control the display unit 4 to display the lower limit threshold, and after releasing the key K2, the display unit 4 displays the analog signal, which can help the staff to observe the deviation between the lower limit threshold and the analog signal; pressing the key K3 can enter the upper limit threshold setting mode, and in the upper limit setting mode, the size of the upper limit threshold can be adjusted by operating the key K1 and the key K2; in the upper limit setting mode, pressing the key K3 again can enter the lower limit threshold setting mode, and in the lower limit setting mode, the size of the lower limit threshold can be adjusted by operating the key K1 and the key K2; in the lower limit setting mode, pressing the key K4 again can determine that the threshold modification is completed.

[0086] In some embodiments, as shown in FIG. 6, the key unit 6 can include a plurality of keys, each of which is connected to the processing unit 3 respectively, so that the staff can input the threshold setting instruction or the display control instruction to the processing unit 3 by operating the corresponding key. Figure 8 As shown, the key unit 6 can include a plurality of keys, each of which is connected to the processing unit 3 respectively, so that the staff can input the threshold setting instruction or the display control instruction to the processing unit 3 by operating the corresponding key. Specifically, the number of keys can be 4, including the key K1, the key K2, the key K3 and the key K4. The operating principle of the key unit 6 can be: pressing the key K1 can control the display unit 4 to display the upper limit threshold, and after releasing the key K1, the display unit 4 displays the analog signal, which can help the staff to observe the deviation between the upper limit threshold and the analog signal; pressing the key K2 can control the display unit 4 to display the lower limit threshold, and after releasing the key K2, the display unit 4 displays the analog signal, which can help the staff to observe the deviation between the lower limit threshold and the analog signal; pressing the key K3 can enter the upper limit threshold setting mode, and in the upper limit setting mode, the size of the upper limit threshold can be adjusted by operating the key K1 and the key K2; in the upper limit setting mode, pressing the key K3 again can enter the lower limit threshold setting mode, and in the lower limit setting mode, the size of the lower limit threshold can be adjusted by operating the key K1 and the key K2; in the lower limit setting mode, pressing the key K4 again can determine that the threshold modification is completed.

[0087] In some embodiments, as shown in FIG. 6, the key unit 6 can include a plurality of keys, each of which is connected to the processing unit 3 respectively, so that the staff can input the threshold setting instruction or the display control instruction to the processing unit 3 by operating the corresponding key. Figure 1 As shown, the key unit 6 can include a plurality of keys, each of which is connected to the processing unit 3 respectively, so that the staff can input the threshold setting instruction or the display control instruction to the processing unit 3 by operating the corresponding key. Specifically, the number of keys can be 4, including the key K1, the key K2, the key K3 and the key K4. The operating principle of the key unit 6 can be: pressing the key K1 can control the display unit 4 to display the upper limit threshold, and after releasing the key K1, the display unit 4 displays the analog signal, which can help the staff to observe the deviation between the upper limit threshold and the analog signal; pressing the key K2 can control the display unit 4 to display the lower limit threshold, and after releasing the key K2, the display unit 4 displays the analog signal, which can help the staff to observe the deviation between the lower limit threshold and the analog signal; pressing the key K3 can enter the upper limit threshold setting mode, and in the upper limit setting mode, the size of the upper limit threshold can be adjusted by operating the key K1 and the key K2; in the upper limit setting mode, pressing the key K3 again can enter the lower limit threshold setting mode, and in the lower limit setting mode, the size of the lower limit threshold can be adjusted by operating the key K1 and the key K2; in the lower limit setting mode, pressing the key K4 again can determine that the threshold modification is completed.

[0088] Figure 9 is the circuit principle diagram of the alarm indication unit in an embodiment of the utility model. In some embodiments, as shown in FIG. 6, the key unit 6 can include a plurality of keys, each of which is connected to the processing unit 3 respectively, so that the staff can input the threshold setting instruction or the display control instruction to the processing unit 3 by operating the corresponding key. Figure 9As shown, the alarm indicating unit 7 can include a second LED lamp D2, a seventeenth resistor R21, a third LED lamp D4 and an eighteenth resistor R22. The anode of the second LED lamp D2 is connected to the third direct current voltage, and the cathode of the second LED lamp D2 is connected to the processing unit 3 through the seventeenth resistor R21. When the analog signal is greater than the upper threshold, the processing unit 3 outputs a low level to the seventeenth resistor R21, and the second LED lamp D2 is lighted (equivalent to outputting an indicating signal), thereby prompting the staff that the analog signal is greater than the upper threshold. The anode of the third LED lamp D4 is connected to the third direct current voltage, and the cathode of the third LED lamp D4 is connected to the processing unit 3 through the eighteenth resistor R22. When the analog signal is less than the lower threshold, the processing unit 3 outputs a low level to the eighteenth resistor R22, and the third LED lamp D4 is lighted (equivalent to outputting an indicating signal), thereby prompting the staff that the analog signal is less than the lower threshold. In addition, the seventeenth resistor R21 and the eighteenth resistor R22 respectively play a role in limiting the working current of the second LED lamp D2 and the third LED lamp D4. It should be noted that the alarm indicating unit 7 is different from the alarm unit 5 in the prompting position. The alarm indicating unit 7 is arranged on the circuit board of the nuclear power plant signal deviation display circuit or device, and mainly outputs a prompt light signal at the site (such as a monitoring room) of the nuclear power plant signal deviation display circuit or device. The alarm unit 5 acts on the upper limit alarm and the lower limit alarm arranged at the site (such as a nuclear island, a pedestrian passage, etc.) of the plant.

[0089] In some embodiments, as shown in Figure 1 The nuclear power plant signal deviation display circuit can further include a power supply unit 8. The power supply unit 8 is connected to the differential amplification unit 1, the conversion unit 2, the processing unit 3, the display unit 4 and the alarm unit 5, and is used to output a second direct current voltage, a third direct current voltage and a fourth direct current voltage to supply power to the differential amplification unit 1, the conversion unit 2, the processing unit 3, the display unit 4 and the alarm unit 5.

[0090] Figure 10 is a circuit principle diagram of the direct current voltage conversion unit in an embodiment of the utility model. Figure 11 is a circuit principle diagram of the positive and negative voltage conversion unit in an embodiment of the utility model. Figure 12 is a circuit principle diagram of the reference voltage unit in an embodiment of the utility model. In some embodiments, the power supply unit 8 can include a direct current voltage conversion unit as shown in Figure 10 a positive and negative voltage conversion unit as shown in Figure 11 and a reference voltage unit as shown in Figure 12

[0091] In some embodiments, as shown in Figure 10 ​As shown, the DC-DC voltage conversion unit may include a DC-DC voltage conversion module U11. The high-voltage side of the DC-DC voltage conversion module U11 can be connected to an input power source (such as 24V DC voltage), and the low-voltage side of the DC-DC voltage conversion module U11 outputs the aforementioned fourth DC voltage. Further, the DC-DC voltage conversion unit may also include a first inductor L1, a first input filter capacitor C3, a second input filter capacitor C4, a varistor MOV1, a fuse F1, a first filter capacitor C1, a second filter capacitor C6, an output filter capacitor C2, a fourth LED D11, and a nineteenth resistor R11. For specific connection structures, please refer to [reference needed]. Figure 10 The circuit consists of a first inductor L1, a first input filter capacitor C3, and a second input filter capacitor C4, forming a CLC filter circuit that filters out noise from the input power supply and improves power supply stability. The first filter capacitor C1 and the second filter capacitor C6 are used to filter out interference noise from the fourth DC voltage. The output filter capacitor C2 reduces the ripple of the fourth DC voltage. The fourth LED D11 illuminates when the fourth DC voltage is output normally, indicating that the fourth DC voltage output is normal. Additionally, the DC-DC voltage conversion module U11 can be a URF2405LP model DC-DC voltage conversion module.

[0092] In some embodiments, such as Figure 11 As shown, the positive-to-negative voltage conversion unit may include a positive-to-negative voltage conversion module U15, an eighth capacitor C25, a ninth capacitor C50, a tenth capacitor C49, a second inductor L2, and a third inductor L3. Please refer to the following for the specific connection structure. Figure 11 Among them, the positive and negative voltage conversion module U15 can be a TPS60403 voltage conversion module. Please refer to [link / reference]. Figure 2 The positive and negative voltage conversion unit is used to provide positive power (S_5V) and negative voltage (S_-5V) to the first and second operational amplifiers. In addition, the positive power supply is filtered by the second inductor L2 and the third inductor L3 to obtain a fifth DC voltage (VCC_5V), which powers the analog-to-digital converter U12 and the level shifter U4.

[0093] In some embodiments, such as Figure 12 As shown, the reference voltage unit may include a voltage reference chip U31, a fifth capacitor C20, a sixth capacitor C21, and a seventh capacitor C22. Please refer to the following for the specific connection structure. Figure 11 Among them, the voltage reference chip U31 can be an existing voltage reference chip, as long as it can output a DC voltage of 2.5V at a certain temperature.

[0094] The working principle of the utility model is as follows: firstly, the differential amplification unit is used for amplifying and filtering the analog signal, so that the subsequent circuit can accurately detect, and the drift and noise signal in the analog signal are effectively suppressed; then, the conversion unit is used for accurately detecting the differential processed signal and converting it into a digital signal; then, the processing unit is used for controlling the working of the display unit and the alarm unit according to the digital signal; then, the display unit is used for displaying the signal deviation information, so as to help the staff to observe the deviation condition of the analog signal; finally, the alarm unit is used for outputting an alarm signal when the analog signal deviation exceeds the threshold value, so as to prompt the staff to handle the abnormality as soon as possible. Understandably, the utility model can effectively suppress the drift and noise signal in the analog signal, improve the precision of the analog signal, and realize the technical effect of accurately displaying the analog signal deviation, which plays a positive role in improving the safety of the nuclear power plant.

[0095] Figure 13 is a curve graph of the analog signal measurement value and the error value of a certain analog signal after being processed by the utility model. Please refer to Figure 13 , is a curve graph of the analog signal measurement value and the error value of a certain analog signal after being processed by the utility model. The curve 100 represents the voltage curve of the analog signal under the full range, and the curve 200 represents the error voltage curve corresponding to the analog signal under the full range. It can be seen that the error voltage is kept below 0.04mV under the full flow, which indicates that the utility model has a very significant effect on improving the precision of the analog signal.

[0096] The utility model also provides a nuclear power plant signal deviation display device which comprises the nuclear power plant signal deviation display circuit provided by the utility model embodiment.

[0097] Understandably, the above embodiment only expresses the preferred implementation manner of the utility model, and the description is more specific and detailed, but it cannot be understood as the limitation of the patent range of the utility model; it should be pointed out that, for ordinary skilled persons in the art, the above technical features can be freely combined without departing from the concept of the utility model, and a plurality of modifications and improvements can be made, which all belong to the protection range of the utility model; therefore, all the equivalent transformations and modifications of the utility model claim range should belong to the coverage range of the utility model claim.

Claims

1. A nuclear power plant signal deviation display circuit, characterized by, The application relates to a signal deviation detection device, which comprises the following parts: a differential amplification unit for accessing an analog signal and amplifying and filtering the analog signal to form a differential processed signal; a conversion unit connected with the differential amplification unit for receiving the differential processed signal and converting the differential processed signal into a digital signal; a processing unit connected with the conversion unit for receiving the digital signal and outputting signal deviation information of the analog signal and an alarm control instruction; a display unit connected with the processing unit for receiving the signal deviation information and displaying the signal deviation information; and an alarm unit connected with the processing unit for receiving the alarm control instruction and outputting an alarm signal. The differential amplification unit comprises:

2. The nuclear power plant signal deviation display circuit in accordance with claim 1, characterized by, a voltage division and impedance conversion unit for accessing the analog signal, dividing the voltage of the analog signal and inputting impedance conversion of the voltage-divided analog signal to form a converted signal; and a signal amplification unit connected with the voltage division and impedance conversion unit and the conversion unit for receiving the converted signal and amplifying the converted signal to form the differential processed signal. The voltage division and impedance conversion unit comprises a first operational amplifier integrated device U16, a first resistor R42, a second resistor R43, a third resistor R44 and a fourth resistor R51; wherein the first operational amplifier integrated device U16 comprises a first operational amplifier and a second operational amplifier; 3. The nuclear power plant signal deviation display circuit according to claim 2, characterized in that, a first end of the first resistor R42 accesses the analog signal, a second end of the first resistor R42 is connected with a non-inverting input end of the first operational amplifier and connected to the ground through the second resistor R43, an inverting input end and an output end of the first operational amplifier are connected and then connected to an inverting input end of the second operational amplifier through the third resistor R44, the inverting input end of the second operational amplifier is also connected to the output end of the second operational amplifier and the signal amplification unit through the fourth resistor R51, and a non-inverting input end of the second operational amplifier is grounded. The signal amplification unit comprises a second operational amplifier integrated device U17, a fifth resistor R45, a sixth resistor R46, a seventh resistor R47 and an eighth resistor R48; wherein the second operational amplifier integrated device U17 comprises a third operational amplifier; 4. The nuclear power plant signal deviation display circuit in accordance with claim 2, wherein, an inverting input end of the third operational amplifier is connected to the voltage division and impedance conversion unit through the fifth resistor R45 and connected to an output end of the third operational amplifier through the sixth resistor R46, a non-inverting input end of the third operational amplifier is connected to a first direct current voltage through the seventh resistor R47 and connected to the ground through the eighth resistor R48, and the output end of the third operational amplifier is also connected with the conversion unit. The conversion unit comprises:

5. The nuclear power plant signal deviation display circuit in accordance with claim 1, wherein, an analog-digital conversion unit connected with the differential amplification unit for receiving the differential processed signal and converting the differential processed signal into a digital signal; and a communication level conversion unit connected between the analog-digital conversion unit and the processing unit for receiving the digital signal and isolating the digital signal. The display unit comprises:

6. The nuclear power plant signal deviation display circuit in accordance with claim 1, wherein, ​ A nixie tube driving unit, connected with the processing unit, for receiving the display instruction outputted by the processing unit; and A nixie tube unit, connected with the nixie tube driving unit, for receiving the display instruction and displaying the signal deviation information.

7. The nuclear power plant signal deviation display circuit according to any one of claims 1 to 6, characterized in that, The nuclear power plant signal deviation display circuit further comprises: A key unit, connected with the processing unit, for outputting a threshold setting instruction capable of setting the upper limit threshold and the lower limit threshold and a display control instruction capable of controlling the display content of the display unit according to the operation; An alarm indication unit, connected with the processing unit, for outputting an indication signal when the analog signal is greater than the upper limit threshold or the analog signal is less than the lower limit threshold.

8. The nuclear power plant signal deviation display circuit in accordance with claim 7, characterized by, The alarm unit comprises: An upper limit alarm unit, connected with the processing unit, for outputting an upper limit alarm signal when the analog signal is greater than the upper limit threshold; and A lower limit alarm unit, connected with the processing unit, for outputting an upper limit alarm signal when the analog signal is less than the lower limit threshold.

9. The nuclear power plant signal deviation display circuit in accordance with claim 8, wherein, The upper limit alarm unit and the lower limit alarm unit respectively comprise a relay K5, a switch tube Q1, a twelfth resistor R4 and a thirteenth resistor R6; the first end of the exciting coil of the relay K5 is connected with the fourth direct current voltage, and the second end is connected with the input end of the switch tube Q1; the control end of the switch tube Q1 is connected to the processing unit through the twelfth resistor R4 in one way and connected to the output end of the switch tube Q1 and the ground through the thirteenth resistor R6 in another way; and the common contact and the normally open contact of the relay K5 are used for connecting an alarm.

10. A nuclear power plant signal deviation display device, characterized by comprising: The nuclear power plant signal deviation display circuit comprises the nuclear power plant signal deviation display circuit according to any one of claims 1 to 9.

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