Electronic multi-channel resistance output card and application thereof

Abstract

The application discloses an electronic multi-channel resistance output card and application thereof, and provides the electronic multi-channel resistance output card which can provide multi-channel resistance analog signals, and the resistance value of each channel can be continuously adjusted on line, thereby providing sufficient resistance analog signals for a reactor protection system logic check, effectively reducing equipment expenditure and saving cost; meanwhile, the application adjusts the bias voltage of an operational amplifier through a voltage balance module, so that the card output has no polarity requirement for external circuits, can support conventional two-wire system, three-wire system and other wiring modes, and can realize data interaction with an external master control card supporting the same communication mode through a communication module, so that the setting and on-line adjustment of the working mode and preset resistance value of the card are realized, the card can be applied to various application occasions, has high universality, is convenient to operate, small in size and high in precision.

Description

Technical Field

[0001] This invention belongs to the field of nuclear reactor instrumentation and control technology, specifically relating to an electronic multi-channel resistor output card and its application. Background Technology

[0002] Nuclear reactor control and protection systems require periodic logic verification according to relevant requirements. This verification mainly includes two aspects: 1) checking the correctness of the protection logic; and 2) verifying the accuracy of the actual action threshold of the protection logic. To accomplish these two tasks, multiple simulated signal combinations need to be simultaneously input to the device under test via external equipment. Each simulated signal can be continuously adjusted within a preset range to simulate the triggering conditions of the protection logic, thereby verifying whether the protection system logic can be triggered correctly.

[0003] Because control and protection systems are relatively complex, there are many logics that need to be verified. Furthermore, each logic is associated with a large number of signal channels and thresholds, resulting in a vast number of signal condition combinations that need to be simulated. For example, for an analog protection logic with m channels, the number of thresholds is Xi (i = 1, 2, 3, 4…m). Therefore, based on permutations and combinations, the number of condition combinations that need to be verified is N = (X1+1)(X2+1)(X3+1)(X4+1)….(Xm-1+1)(Xm+1).

[0004] Because the logic verification of nuclear reactor protection systems requires a large number of analog signal channels, existing signal simulation devices or equipment can typically only provide 1-2 channels of analog signals. This results in a large amount of equipment required for logic verification, and the coordination between multiple devices requires additional debugging tools or equipment, which increases the labor intensity and professional skill requirements of personnel. In addition, existing signal simulation devices that can provide multiple channels of signals simultaneously are designed for specific applications and cannot be applied to other applications, resulting in poor versatility. All of these problems lead to high costs and low efficiency in the logic verification of nuclear reactor protection systems. Summary of the Invention

[0005] To address the problems of low efficiency and high cost in nuclear reactor protection system verification caused by existing signal simulation devices being limited to a few channels of analog signals or existing devices that can provide multi-channel signals being only applicable to specific applications and lacking versatility, this invention provides an electronic multi-channel resistor output card and its application. The electronic high-precision resistor output card provided by this invention can simultaneously output multiple channels of resistance signals, and the resistance value of each channel can be continuously adjusted online. It can automatically load signals, is adaptable to various logic verification applications, and has the advantages of strong versatility, high efficiency, and low cost.

[0006] This invention is achieved through the following technical solution:

[0007] An electronic multi-channel resistor output card and its application, the electronic multi-channel resistor output card comprising:

[0008] The resistance control module receives the preset resistance value from the external main control card through the communication module and converts it into a drive command to drive the digital-to-analog converter module and the operational amplifier module.

[0009] A digital-to-analog conversion module, comprising an n-channel digital-to-analog converter, is used to receive data from the resistance control module and convert it into n-channel analog output;

[0010] An operational amplifier module, comprising n operational amplifiers, which respectively amplify and gain the analog signals output by the n digital-to-analog converters;

[0011] A voltage balancing module, comprising n voltage balancing circuits, adjusts the bias voltage of each of the n operational amplifiers to compensate for bias instability and make the operational amplifiers output in the first and fourth quadrants consistent.

[0012] The protection circuit includes n channels, which output the signals from the n operational amplifiers to an external circuit. Each channel is equipped with an overvoltage protection circuit and an overcurrent protection circuit.

[0013] A voltage feedback module, comprising n sampling modules, which respectively collect feedback reference voltages from n channels and transmit them to the corresponding digital-to-analog converters;

[0014] In addition, a communication module is used for data interaction between the resistance control module and the main control card to complete the working mode setting and preset resistance value setting for each channel;

[0015] n is an integer greater than 2.

[0016] Traditional reactor protection system logic verification methods suffer from a large number of condition combinations, while a single device can only provide 1-2 channels of analog signals. This necessitates numerous debugging tools and equipment with poor versatility, and places high demands on personnel's labor intensity and skill levels, resulting in low efficiency and high cost. In contrast, the electronic multi-channel resistor output card proposed in this invention provides multi-channel resistor analog signals, with the resistance value of each channel continuously adjustable online. This provides sufficient resistor analog signals for reactor protection system logic verification, effectively reducing equipment expenditure and saving costs. Furthermore, by incorporating a voltage balancing module to adjust the bias voltage of the operational amplifier, the card output has no polarity requirement for external circuits, supporting conventional two-wire and three-wire wiring methods. Through a communication module, it can interact with any external master control card supporting the same communication mode, enabling the setting and online adjustment of the card's operating mode and preset resistance values. This makes it suitable for various applications, highly versatile, easy to operate, small in size, and highly accurate.

[0017] In a preferred embodiment, the electronic multi-channel resistor output card of the present invention further includes:

[0018] A power supply module is provided to power the internal modules of the electronic multi-channel resistor output card.

[0019] In a preferred embodiment, the value of n in this invention is 8 or 16.

[0020] In a preferred embodiment, the output value of the i-th digital-to-analog converter of the present invention is:

[0021] Viout = Viref * Di / 65536,

[0022] Where Viref is the feedback reference voltage of channel i, and Di is the data output to channel i by the resistance control module.

[0023] In a preferred embodiment, the output value of the i-th operational amplifier of the present invention is: Viout*Ki, where Ki is the gain coefficient.

[0024] In a preferred embodiment, the feedback reference voltage output by the sampling module of channel i of the present invention is:

[0025] Viref = I * Rsi, where Rsi is the sampling resistance of channel i and I is the loop current.

[0026] In a preferred embodiment, the communication module of the present invention adopts a CAN communication module.

[0027] In a preferred embodiment, the power supply module of the present invention provides DC 12V, DC 5V and DC 3.3V power.

[0028] In a preferred embodiment, the n channels of the protection circuit of the present invention are connected to the external circuit by hard-wiring.

[0029] On the other hand, the present invention also proposes a logic verification method for a reactor protection system, wherein the method uses the electronic multi-channel resistor output card described in the present invention to provide n-channel temperature simulation signals for the logic verification of the reactor protection system.

[0030] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0031] 1. The electronic multi-channel resistor output card proposed in this invention outputs physical resistance values ​​electronically, and can simultaneously output multiple channels of analog resistance signals. It adopts automatic control and drive technology to realize real-time online adjustment and rapid output of the resistance value of each channel. At the same time, this invention also adjusts the bias voltage of the operational amplifier by setting a voltage balance module, compensating for the bias instability of the operational amplifier, reducing the output deviation of the operational amplifier in the first and fourth quadrants, and solving the problem of large forward and reverse output deviations. This makes the entire card output channel connection with external circuits without polarity requirements, and can support conventional wiring methods such as two-wire and three-wire systems. Moreover, through the communication module, it can be adapted to any external master control card that supports the same communication mode, realize the setting and adjustment of working mode and preset resistance value, and is applicable to a variety of applications. It has high versatility, improves logic verification efficiency, and saves costs.

[0032] 2. The electronic multi-channel resistor output card proposed in this invention, in conjunction with the main control card, can quickly and efficiently output, switch, and adjust the resistance values ​​of multiple channels, realize automatic signal loading, and achieve a resolution of 0.1 ohms. It meets the temperature simulation function requirements of analog logic verification work, with an accuracy of 0.1℃. It has the advantages of small size, multiple channels, digitalization, programmability, and high precision.

[0033] 3. The electronic multi-channel resistor output card proposed in this invention is generally applicable to situations where multiple resistor outputs are required during the debugging, testing and maintenance of control systems. It is particularly suitable for the logic verification process of reactor protection systems and has broad application prospects in nuclear power, research reactors, experimental reactors and other large nuclear facilities. Attached Figure Description

[0034] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0035] Figure 1 This is a block diagram illustrating the principle of an electronic high-precision resistor output card according to an embodiment of the present invention.

[0036] Figure reference numerals and corresponding component names:

[0037] 1-Resistance control module, 2-Digital-to-analog conversion module, 3-Voltage balance module, 4-Operational amplifier module, 5-Protection circuit, 6-Voltage feedback module, 7-Communication module, 8-Power supply module. Detailed Implementation

[0038] In the following, the terms “comprising” or “may include” as used in various embodiments of the invention indicate the presence of an inventive function, operation, or element, and do not limit the addition of one or more functions, operations, or elements. Furthermore, as used in various embodiments of the invention, the terms “comprising,” “having,” and their cognates are intended only to indicate a specific feature, number, step, operation, element, component, or combination of the foregoing, and should not be construed as primarily excluding the presence of one or more other features, numbers, steps, operations, elements, components, or combinations of the foregoing, or adding one or more combinations of the foregoing.

[0039] In various embodiments of the invention, the expression "or" or "at least one of A and / or B" includes any combination or all combinations of the words listed simultaneously. For example, the expression "A or B" or "at least one of A and / or B" may include A, may include B, or may include both A and B.

[0040] The expressions used in the various embodiments of the present invention (such as "first," "second," etc.) may modify various constituent elements in the various embodiments, but do not limit the corresponding constituent elements. For example, the above expressions do not limit the order and / or importance of the elements. The above expressions are only used for the purpose of distinguishing one element from other elements. For example, a first user device and a second user device refer to different user devices, although both are user devices. For example, a first element may be referred to as a second element without departing from the scope of the various embodiments of the present invention, and similarly, a second element may also be referred to as a first element.

[0041] It should be noted that if a description is made of "connecting" one component to another, then the first component can be directly connected to the second component, and a third component can be "connected" between the first and second components. Conversely, when a component is "directly connected" to another component, it can be understood that there is no third component between the first and second components.

[0042] The terminology used in the various embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to limit the various embodiments of the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which the various embodiments of the invention pertain. The terms (such as those defined in a generally used dictionary) are to be interpreted as having the same meaning as in the context of the relevant technical field and are not to be interpreted as having an idealized or overly formal meaning, unless clearly defined in the various embodiments of the invention.

[0043] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0044] Example:

[0045] Traditional logic verification methods for nuclear reactor control systems suffer from a large number of condition combinations, while a single device can only provide 1-2 channels of analog signals. This necessitates a significant investment in equipment, requires additional debugging tools for inter-device coordination, and places higher demands on personnel's labor intensity and professional skills. Furthermore, analog devices capable of providing multi-channel signals are typically designed for specific application scenarios, lacking versatility. These issues lead to low efficiency and high costs in nuclear reactor protection system logic verification. To address this, this embodiment proposes an electronic multi-channel resistor output card and its application. The proposed electronic high-precision resistor output card provides multiple channels of analog resistance signals, with the resistance value of each channel continuously adjustable online. This provides sufficient analog resistance signals for protection system logic verification, effectively reducing equipment costs. Moreover, the output resistance value of the proposed electronic high-precision resistor output card has no polarity requirement for external circuitry, supports conventional wiring methods such as two-wire and three-wire systems, and is applicable to various applications, exhibiting high versatility.

[0046] Specifically, such as Figure 1 As shown, the electronic high-precision resistor output card proposed in this embodiment includes a resistance control module 1, a DAC digital-to-analog conversion module 2, a voltage balance module 3, an operational amplifier 4, a protection circuit 5, a voltage feedback module 6, a communication module 7, and a power supply module 8.

[0047] Among them, the resistance control module 1 is connected to the DAC digital-to-analog converter module 2 through a PCB etching circuit; the DAC digital-to-analog converter module 2 is connected to the resistance control module 1, the operational amplifier module 4, and the voltage feedback module 6 through a PCB etching circuit; the voltage balance module 3 is connected to the operational amplifier module 4 through a PCB etching circuit; the protection circuit 5 is connected to the operational amplifier module 4 and the voltage feedback module 6 through a PCB etching circuit; the power supply module 8 is connected to the resistance control module 1, the DAC digital-to-analog converter module 2, the voltage balance module 3, the operational amplifier module 4, the voltage feedback module 6, and the communication module 7 through a PCB etching circuit; the resistance control module 1 is connected to the communication module 7 through communication; the communication module 7 is connected to the main control card through a bus; and the protection circuit 5 is connected to the external circuit through hardwiring.

[0048] The electronic high-precision resistor output card proposed in this embodiment transmits the preset resistance value of the main control card to the resistance control module 1 through the communication module 7. The resistance control module 1 sends the preset resistance value to the DAC digital-to-analog converter module 2, which converts it into a voltage signal. The operational amplifier module 4 amplifies the voltage signal and then connects it to the external circuit through the protection circuit 5. The ratio of its output voltage to current is the preset resistance value, thereby realizing controllable resistance output.

[0049] The working principle of the electronic high-precision resistor output card proposed in this embodiment is as follows: A preset resistance value is written into the resistance control module via a communication module. By collecting the loop current value and the sampling resistor, a sampling voltage value is obtained. A digital-to-analog converter is used to establish the relationship between the preset resistance value and the output voltage, thereby achieving controllable loop current and voltage. Ohm's law is used to output the preset resistance value, realizing the electronic output of the physical resistance value. Multiple channels can be output simultaneously (e.g., ...). Figure 1 The 8-channel analog resistance signal shown significantly reduces the number of devices required. Utilizing automatic control and drive technology, it is easy to operate, reducing the workload and professional requirements for personnel, significantly shortening the work cycle, improving logic verification efficiency, and lowering costs. Furthermore, the voltage balancing module balances the operational amplifiers, making the card's output polarity independent of external circuits, supporting conventional two-wire and three-wire wiring methods. Through the communication module, it can communicate with any external master control card or device supporting the same communication method, enabling rapid and efficient output, switching, and adjustment of resistance values ​​across multiple channels. This card boasts advantages such as small size, multiple channels, digitalization, programmability, high precision, and high versatility.

[0050] It should be noted that, Figure 1 An 8-channel resistance signal output card is presented, which is only an illustrative example and does not limit the number of output channels. The number of channels can be set according to actual needs, such as the conventional 16 channels.

[0051] In one optional implementation, the resistance control module 1 employs an industrial-grade embedded chip, forming the core driving component of the entire card. The resistance control module 1 receives input data from the main control card via the communication module 7, converts it into driving instructions, and then drives eight subsequent digital-to-analog converters and operational amplifiers to complete the resistance conversion. Finally, it outputs the preset resistance value to the external circuit. The output value of the resistance output module 1 is Di = 65536Ri / Rsi, where Ri is the preset resistance value, Rsi is the sampling resistance value, and i is the channel number (1 ≤ i ≤ 8). The resistance control module 1 is programmable. Through communication between the main control card and the resistance control module, it drives subsequent conversion circuits, enabling rapid conversion, amplification, tracking, and adjustment, achieving automatic signal loading.

[0052] Meanwhile, communication module 7 supports any other master control card or device with the same communication function. Through this module, the operating mode and resistance value of each channel of the card can be set via communication with the external master control card (device). Real-time online adjustment of the resistance value of each channel is possible, offering wide applicability and good versatility. Specifically, the output resistance range of each channel of the card is 100.00-247.09 ohms, corresponding to a temperature range of 0-400℃, with an accuracy of 0.1℃, meeting PT100 specifications.

[0053] It should be noted that the number of digital-to-analog converters in the DAC module and operational amplifiers in the operational amplifier module are consistent with the number of output channels on the card. Therefore, based on the number of output channels on the card, i.e., 8 channels, 8 sets of DAC digital-to-analog converters and operational amplifiers are set up accordingly. Figure 1 This is merely an illustrative example and does not limit the number of digital-to-analog converters in the DAC module or the number of operational amplifiers in the operational amplifier module.

[0054] In one optional implementation, the DAC digital-to-analog converter module 2 includes eight 16-bit multiplication digital-to-analog converters, which are responsible for receiving data from the resistance control module 1 and converting it into eight channels of analog quantity (voltage Viout) output. The output value Viout = Viref * Di / 65536, where Viref is the feedback reference voltage of channel i, and Di is the data output by the resistance control module 1 to the i-th channel.

[0055] In one optional implementation, the voltage balancing module 3 includes eight sets of voltage balancing circuits based on TLV431. The eight operational amplifiers are balanced using potentiometers in the balancing circuits. By adjusting the positions of the potentiometers in the voltage balancing circuits, the bias voltage of the operational amplifiers is adjusted, compensating for the bias instability of the core operational amplifier and reducing the output deviation of the core operational amplifier in the first and fourth quadrants. This solves the technical problem of large forward and reverse output deviations, enabling the entire card to output a preset resistance value regardless of whether it operates under forward or reverse voltage conditions. In other words, the card's output channel has no polarity requirement for connection to external circuits, supporting conventional wiring methods such as two-wire and three-wire systems, making it widely applicable and highly versatile.

[0056] It should be noted that the number of voltage balancing circuit groups in voltage balancing module 3 is the same as the number of output channels of the card. Therefore, since the card has 8 channels, voltage balancing module 3 is equipped with 8 voltage balancing circuit groups. Figure 1 This is merely an illustrative example and does not limit the number of voltage balancing circuit groups in voltage balancing module 3.

[0057] In one optional implementation, the protection circuit includes eight channel protection circuits, each with overvoltage protection, overcurrent protection, and filtering functions, which can protect the core driver of the card, i.e., the resistance control module 1, from being burned out in the event of an external circuit malfunction.

[0058] It should be noted that the number of channels in the protection circuit is the same as the number of output channels in the card. Figure 1 This is merely an illustrative example and does not limit the number of channels in the protection circuit.

[0059] In one optional implementation, the voltage feedback module 6 includes an 8-channel sampling module. Each channel consists of a precision sampling resistor Rsi and a signal conversion circuit. It is responsible for collecting the feedback reference voltage Viref = I * Rsi, where I is the feedback loop current. The feedback loop is the loop formed by the resistor output card and the external circuit.

[0060] It should be noted that the number of channels in voltage feedback module 6 is the same as the number of output channels in the card, therefore, according to Figure 1 The card shown has 8 output channels, and the voltage feedback module 6 is a sampling module with 8 channels.

[0061] In one optional implementation, the communication module 7 includes a CAN communication module responsible for data exchange between the resistance control module 1 and the main control card, completing the working mode setting and resistance value setting for each channel. The communication module 7 supports any other main control card or main control device with CAN communication functionality. It should be noted that this embodiment uses CAN communication only as an example to adapt to the communication function of the resistance control module and does not limit the communication method of the communication module. In other optional implementations, other suitable communication methods can be used according to actual needs.

[0062] In one optional implementation, the power module 8 adopts a DC 24V input and outputs DC 12V, 5V and 3.3V respectively to meet the power supply requirements of the internal modules of the card.

[0063] The electronic high-precision resistor output card proposed in this embodiment, in conjunction with the main control card, can quickly and efficiently output, switch, and adjust the resistance values ​​of multiple channels, with a resolution of 0.1 ohms. This meets the temperature simulation requirements of analog logic verification work, achieving an accuracy of 0.1℃. This card can improve the efficiency of logic verification, save costs, and has high versatility. It is widely applicable to situations requiring multi-channel resistor output during control system debugging, testing, and maintenance, and is particularly suitable for logic verification in reactor protection systems. It has broad application prospects in nuclear power plants, research reactors, experimental reactors, and other large nuclear facilities.

[0064] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An electronic multi-channel resistor output card for logic verification in a nuclear reactor protection system, characterized in that, The electronic multi-channel resistor output card includes: The resistance control module receives the preset resistance value from the external main control card through the communication module and converts it into a drive command to drive the digital-to-analog converter module and the operational amplifier module. The digital-to-analog conversion module includes n digital-to-analog converters, each of which receives the corresponding channel data output by the resistance control module and converts the received data into an analog output of the corresponding channel in combination with the feedback reference voltage of that channel. An operational amplifier module, comprising n operational amplifiers, which respectively amplify and gain the analog signals output by the n digital-to-analog converters; The voltage balancing module includes n voltage balancing circuits, which adjust the bias voltage of the n operational amplifiers respectively, compensate for the bias instability of the operational amplifiers, make the output of the operational amplifiers consistent in the first and fourth quadrants, and make the output resistance value of the electronic multi-channel resistor output card have no polarity requirement for the external circuit, and are compatible with two-wire and three-wire wiring methods. The protection circuit includes n channels, which output the signals from the n operational amplifiers to an external circuit. Each channel is equipped with an overvoltage protection circuit and an overcurrent protection circuit. A voltage feedback module, comprising n sampling modules, each sampling module acquiring the feedback reference voltage of the corresponding channel and transmitting it to the corresponding digital-to-analog converter; In addition, a communication module is used for data interaction between the resistance control module and the main control card to complete the working mode setting and preset resistance value setting for each channel; n is an integer greater than 2.

2. The electronic multi-channel resistor output card according to claim 1, characterized in that, The electronic multi-channel resistor output card also includes: A power supply module is provided to power the internal modules of the electronic multi-channel resistor output card.

3. An electronic multi-channel resistor output card according to claim 1 or 2, characterized in that, The value of n is either 8 or 16.

4. An electronic multi-channel resistor output card according to claim 1 or 2, characterized in that, The output value of the i-th digital-to-analog converter is: Viout = Viref * Di / 65536, Where Viref is the feedback reference voltage of channel i, and Di is the data output to channel i by the resistance control module.

5. An electronic multi-channel resistor output card according to claim 4, characterized in that, The output value of the i-th operational amplifier is: Viout*Ki, where Ki is the gain coefficient.

6. The electronic multi-channel resistor output card according to claim 4, characterized in that, The feedback reference voltage output by the sampling module of channel i is: Viref = I * Rsi, where Rsi is the sampling resistance of channel i and I is the loop current.

7. An electronic multi-channel resistor output card according to claim 1 or 2, characterized in that, The communication module uses a CAN communication module.

8. An electronic multi-channel resistor output card according to claim 2, characterized in that, The power module provides DC 12V, DC 5V and DC 3.3V power.

9. An electronic multi-channel resistor output card according to claim 1 or 2, characterized in that, The protection circuit has n channels that are connected to an external circuit via hardwiring.

10. A logic verification method for a reactor protection system, characterized in that, The method uses the electronic multi-channel resistor output card as described in any one of claims 1-9 to provide n-channel temperature simulation signals for the logic verification of the reactor protection system.

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