Power supply conversion method and system for ash removal level gage control loop of thermal power plant

Abstract

The invention discloses a power supply conversion method and system for a control loop of a thermal power plant ash removal level gage, and relates to the technical field of ash removal level gage control, and the method comprises the steps: adding two relays in the control loop, and introducing a 220V AC voltage power supply; a 220V alternating current power supply is connected to the tuning fork level gage; the relay receives the pressure drop when the tuning fork level gage acts; dCS feedback signals are connected to relay nodes, real-time feedback of material level information is provided through state changes of relays, and the state of the tuning fork level gage is remotely monitored. According to the invention, the power supply conversion of the control loop of the ash removal level gage is realized, the problems that the used power supply is a 220V AC voltage tuning fork level gage, the node output and the power supply are the same cable, and the DCS card node input is direct current voltage 48VDC are solved, and a high-voltage level gage node used on site is converted into a low-voltage node; the problem that due to different voltages, the level gage breaks down and cannot act normally is solved, and normal operation of soot blowing sequential control is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of power conversion, and in particular to a method and system for converting a control loop power supply of an ash removal level meter in a thermal power plant. Background Art

[0002] At present, some thermal power plants use 220VAC tuning fork level meters as the power supply. The node output and the power supply are in the same cable. Since the DCS card output voltage is 48VDC, it is unable to generate 220VAC voltage for it. As a result, the level meter often displays inaccurately, frequently fails to display full material or fails to provide signals when full, etc., causing the dry ash removal program to be unable to proceed normally, and even causing ash leakage in the dry ash removal pipe, resulting in environmental pollution.

[0003] The invention solves the feedback problem of a material level meter of a type in which power supply and signal are shared by a common cable. Summary of the invention

[0004] In view of the above-mentioned problems, the present invention is proposed.

[0005] Therefore, the problem to be solved by the present invention is: how to solve the problem that the existing ash level meter for thermal power plant ash removal shares a cable with the power supply and the signal, and the output voltage of the DCS system does not match the voltage required by the level meter, resulting in frequent inaccurate display and signal failure in actual application, which not only affects the normal progress of the dry ash removal program, but also may cause environmental pollution due to ash leakage.

[0006] To solve the above technical problems, the present invention provides the following technical solutions: a power conversion method for a control circuit of an ash removal level meter in a thermal power plant, comprising: adding two relays in the control circuit to introduce a 220V AC voltage power supply; connecting the 220V AC power supply to the tuning fork level meter; the relay receives a voltage drop when the tuning fork level meter is actuated; accessing a DCS feedback signal at the relay node, using the state change of the relay to provide real-time feedback of the material level information, and remotely monitoring the state of the tuning fork level meter.

[0007] As a preferred solution of the power conversion method for the control circuit of the ash removal level meter in a thermal power plant described in the present invention, the two relays are relay No. 1 and relay No. 2 respectively.

[0008] As a preferred solution of the power conversion method for the control circuit of the ash removal level meter in a thermal power plant described in the present invention, the two relays include two relays to be connected in parallel.

[0009] As a preferred scheme of the power conversion method of the control circuit of the ash removal level meter in a thermal power plant described in the present invention, wherein: the connecting of the 220V AC power supply to the tuning fork level meter includes the live wire end of the 220V AC power supply being input by the input terminal of the No. 1 relay coil and being output by the output terminal of the No. 2 relay coil, the output line being connected to the L end of the tuning fork level meter, and the neutral wire end of the 220V AC power supply being directly connected to the N end of the tuning fork level meter.

[0010] As a preferred solution of the power supply conversion method of the control circuit of the ash level meter of a thermal power plant described in the present invention, the relay receives a voltage drop when the tuning fork level meter is actuated, and the relay is equivalent to the intermediate load link of the tuning fork level meter. If the tuning fork level meter node is actuated, that is, the material body contacts the tuning fork, the overall circuit is turned on, the relay receives the voltage drop, and the relay node is controlled to be closed. If the level meter node is disconnected, the relay node is disconnected.

[0011] As a preferred scheme of the power conversion method of the control circuit of the ash removal level meter in a thermal power plant described in the present invention, the relay receives a voltage drop when the tuning fork level meter is actuated, and if the relay node is closed, the material level is high, and if the relay node is disconnected, the material level is low.

[0012] As a preferred solution of the power conversion method of the control circuit of the ash level meter of a thermal power plant described in the present invention, wherein: the access to the DCS feedback signal on the relay node includes leading out a control line from the closed contact of the relay and connecting it to the digital input end of the DCS system, setting and configuring the input port in the DCS system to ensure that the closed signal from the relay is recognized as an indication that the dust reaches a threshold value, configuring the DCS logic to respond to the relay signal, and automatically triggering the start of the ash removal equipment when the signal is detected to be closed; the use of the state change of the relay to provide real-time feedback of the material level information includes: if the relay node is closed, the state is transmitted to the DCS system as a high material level signal, and ash removal measures are taken; if the relay node is disconnected, the state is transmitted to the DCS system as a low material level signal, and the ash removal operation is stopped; the state of the tuning fork level meter is remotely monitored.

[0013] Another object of the present invention is to provide a system for power conversion method of ash removal level meter control circuit in thermal power plant, which can solve the power conversion problem of ash removal level meter control circuit in thermal power plant by constructing ash removal level meter control circuit power conversion system.

[0014] In order to solve the above technical problems, the present invention provides the following technical solutions: a power conversion system for a control circuit of an ash removal level meter in a thermal power plant, comprising a level meter, a relay, a DCS system module and an ash removal module; the level meter is used to detect whether the dust reaches a threshold value; the relay is used to convert and amplify the switch signal of the tuning fork level meter to ensure that the signal is safely and correctly transmitted to the DCS system, while providing electrical isolation and control functions; the DCS system module is used to receive the signal transmitted by the relay to monitor and control the material level status, and automatically adjust the operation of the ash removal equipment; the ash removal module is used to perform ash removal operations when the relay node is closed.

[0015] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the power conversion method of the control circuit of the ash level meter of a thermal power plant are realized.

[0016] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of the power conversion method for a control loop of an ash level meter in a thermal power plant as described above.

[0017] The beneficial effects of the present invention are as follows: the power conversion method of the control circuit of the ash removal level meter in a thermal power plant provided by the present invention can realize the power conversion of the control circuit of the ash removal level meter, can realize the use of a 220VAC voltage tuning fork level meter, the node output and the power supply are the same cable, and the DCS card node input is a DC voltage of 48VDC, which solves the problem of voltage incompatibility. It can convert the high-voltage level meter node used on site into a low-voltage node, improve the reliability of on-site equipment, effectively avoid the problem that the level meter fails to operate normally due to different voltages, and realize the normal operation of the soot blowing control. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0019] Figure 1 A flow chart of a method for power conversion of a control circuit of an ash removal level meter in a thermal power plant provided in the first embodiment of the present invention.

[0020] Figure 2 A connection diagram of a power conversion method for a control circuit of an ash level meter in a thermal power plant provided in the first embodiment of the present invention.

[0021] Figure 3A structural diagram of a power conversion system for a control circuit of an ash level meter in a thermal power plant provided in a second embodiment of the present invention. DETAILED DESCRIPTION

[0022] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0023] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0024] Example 1

[0025] Reference Figure 1 and Figure 2 , which is the first embodiment of the present invention, provides a power conversion method for a control circuit of an ash removal level meter in a thermal power plant, comprising: adding two relays in the control circuit to introduce a 220V AC voltage power supply; connecting the 220V AC power supply to the tuning fork level meter; the relay receives a voltage drop when the tuning fork level meter is actuated; accessing a DCS feedback signal at the relay node, using the state change of the relay to provide real-time feedback of the material level information, and remotely monitoring the state of the tuning fork level meter.

[0026] Mainly by studying the relationship between power input and output, mainly adding dual relays in parallel in the control loop, introducing a separate 220VAC power supply to control the normal operation of the level meter, and at the same time connecting the dual relay nodes to the new DCS control system to ensure that the level meter can display normally.

[0027] S1. Add two relays in the control circuit and introduce 220V AC voltage power supply.

[0028] The two relays are Relay 1 and Relay 2. The two relays are to be connected in parallel.

[0029] S2. Connect the 220V AC power supply to the tuning fork level meter.

[0030] The live wire of 220V AC power supply is connected to the input terminal of No. 1 relay coil and the output terminal of No. 2 relay coil. The output terminal is connected to the L terminal of the tuning fork level meter. The neutral wire of 220V AC power supply is directly connected to the N terminal of the tuning fork level meter. Figure 2 shown.

[0031] S3, the relay receives the voltage drop when the tuning fork level meter is actuated.

[0032] The relay is equivalent to the intermediate load link of the tuning fork level meter. If the tuning fork level meter node moves, that is, the material body contacts the tuning fork, the overall circuit is connected, the relay receives the voltage drop, and controls the relay node to close. If the level meter node is disconnected, the relay node is disconnected. If the relay node is closed, the material level is high, and if the relay node is disconnected, the material level is low.

[0033] When the tuning fork level meter is activated (for example, the material body contacts the tuning fork, causing the level meter node to activate), the relay will receive a voltage drop, which will cause the relay node to close. When the relay node is closed, a conductive path is formed, allowing the 220V AC power supply to power the tuning fork level meter, so the level meter can send a high level signal. When the level meter node is disconnected, the relay node will also be disconnected, cutting off the power supply from the 220V AC power supply to the level meter, and the level meter will send a low level signal.

[0034] Through this mechanism, the relay actually acts as a switch, controlling the power supply of the tuning fork level meter, realizing real-time feedback and remote monitoring of the material level information. The DCS (distributed control system) obtains the material level information by monitoring the state change of the relay, and controls the start and stop of the ash removal equipment accordingly.

[0035] S4. Connect the DCS feedback signal to the relay node, use the state change of the relay to provide real-time feedback of the material level information, and remotely monitor the state of the tuning fork level meter.

[0036] Lead the control line from the closed contact of the relay and connect it to the digital input of the DCS system. Set and configure the input port in the DCS system to ensure that the closed signal from the relay is recognized as an indication that the dust has reached the threshold. Configure the DCS logic to respond to the relay signal. When the signal closure is detected, it automatically triggers the start of the dust removal equipment.

[0037] If the relay node is closed, the status will be transmitted to the DCS system as a high material level signal, and dust removal measures will be taken; if the relay node is disconnected, the status will be transmitted to the DCS system as a low material level signal, and the dust removal operation will be stopped; the status of the tuning fork level meter can be monitored remotely.

[0038] The tuning fork level meter is powered by a 220VAC power supply. During normal operation, when the level meter is activated, there will be a light indication at the level meter. However, the level meter has no feedback node output and cannot be remotely monitored. This patent can be used to achieve remote monitoring without changing the form of the level meter. After the two relays are connected in parallel, the live wire end of the 220V AC power supply is fed in by the incoming wire end of the No. 1 relay coil and out by the outgoing wire terminal of the No. 2 relay coil. The outgoing wire is connected to the L end of the tuning fork level meter, and the neutral wire end of the 220V AC power supply is directly connected to the N end of the tuning fork level meter. At this time, the relay is equivalent to the intermediate load link of the tuning fork level meter. When the tuning fork level meter node is activated, the overall circuit is turned on. The relay will cause its control node to close due to the voltage drop received. When the level meter node is disconnected, the situation is the opposite. Therefore, the DCS feedback signal is connected to the relay node to achieve the remote monitoring function.

[0039] Example 2

[0040] Reference Figure 3 , which is the second embodiment of the present invention, is different from the previous embodiment in that it provides a power conversion system for a control circuit of an ash removal level meter in a thermal power plant, including: a level meter 100, a relay 200, a DCS system module 300 and an ash removal module 400.

[0041] The material level meter 100 is used to detect whether the dust reaches a threshold value.

[0042] Relay 200 is used to convert and amplify the switch signal of the tuning fork level meter to ensure that the signal is safely and correctly transmitted to the DCS system, while providing electrical isolation and control functions.

[0043] The DCS system module 300 is used to receive the signal transmitted by the relay 100 to monitor and control the material level status and automatically adjust the operation of the ash removal equipment.

[0044] The dust removal module 400 is used to perform dust removal operation when the relay node is closed.

[0045] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program codes.

[0046] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0047] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0048] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0049] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for power conversion of a control circuit of an ash level meter in a thermal power plant, characterized in that: include, Add two relays in the control loop and introduce 220V AC voltage power supply; Connect the 220V AC power supply to the tuning fork level meter; The relay receives the voltage drop when the tuning fork level meter is actuated; The DCS feedback signal is connected to the relay node, and the state change of the relay is used to provide real-time feedback of the material level information, so as to remotely monitor the state of the tuning fork level meter.

2. A method for power conversion of a control circuit of an ash level meter in a thermal power plant according to claim 1, characterized in that: The two relays are relay No. 1 and relay No. 2 respectively.

3. A method for converting the power supply of a control circuit of an ash level meter in a thermal power plant as claimed in claim 2, characterized in that: The two relays include two relays to be connected in parallel.

4. A method for converting the power supply of a control circuit of an ash level meter in a thermal power plant as claimed in claim 3, characterized in that: The method of connecting the 220V AC power supply to the tuning fork level meter includes the following steps: the live wire end of the 220V AC power supply is connected to the input terminal of the No. 1 relay coil, the output terminal of the No. 2 relay coil is connected to the L terminal of the tuning fork level meter, and the neutral wire end of the 220V AC power supply is directly connected to the N terminal of the tuning fork level meter.

5. A method for converting the power supply of a control circuit of an ash level meter in a thermal power plant as claimed in claim 4, characterized in that: The relay receives a voltage drop when the tuning fork level meter is actuated, and the relay is equivalent to the intermediate load link of the tuning fork level meter. If the tuning fork level meter node is actuated, that is, the material body contacts the tuning fork, the overall circuit is turned on, the relay receives the voltage drop, and controls the relay node to close. If the level meter node is disconnected, the relay node is disconnected.

6. A method for converting power supply of a control circuit of an ash level meter in a thermal power plant as claimed in claim 5, characterized in that: The relay receives a voltage drop when the tuning fork level meter is actuated, and if the relay node is closed, the material level is high, and if the relay node is open, the material level is low.

7. A method for power conversion of a control circuit of an ash level meter in a thermal power plant as claimed in claim 6, characterized in that: The accessing of the DCS feedback signal on the relay node includes leading a control line from the closed contact of the relay and connecting it to the digital input terminal of the DCS system, setting and configuring the input port in the DCS system, ensuring that the closed signal from the relay is recognized as an indication that the dust reaches a threshold value, configuring the DCS logic to respond to the relay signal, and automatically triggering the start of the dust removal equipment when the signal is detected to be closed; The provision of real-time feedback of material level information by utilizing the state change of the relay includes transmitting the state as a high material level signal to the DCS system if the relay node is closed, and taking dust removal measures; If the relay node is disconnected, the status is transmitted to the DCS system as a low material level signal, and the ash removal operation is stopped; Remotely monitor the status of the tuning fork level meter.

8. A system using the power conversion method for a control circuit of a ash level meter in a thermal power plant as claimed in any one of claims 1 to 7, characterized in that: It includes a material level meter (100), a relay (200), a DCS system module (300) and an ash removal module (400); The material level meter (100) is used to detect whether the dust reaches a threshold value; The relay (200) is used to convert and amplify the switch signal of the tuning fork material level meter, ensuring that the signal is safely and correctly transmitted to the DCS system, while providing electrical isolation and control functions; The DCS system module (300) is used to receive the signal transmitted by the relay (100) to monitor and control the material level state and automatically adjust the operation of the ash removal equipment; The dust removal module (400) is used to perform a dust removal operation when the relay node is closed.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of a method for power conversion of a control circuit of an ash removal level meter in a thermal power plant according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of a method for power conversion of a control circuit of an ash level meter in a thermal power plant according to any one of claims 1 to 7 are implemented.

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