A monitoring control system and method for operating faults of boiler soot blowers in thermal power plants

Abstract

The present invention discloses a monitoring control system and method for operation failure of a sootblower in a thermal power plant boiler. The operation time of the sootblower obtained by logical calculation is transmitted to a DCS operation screen through a sootblower operation time output function block 309, so as to provide intuitive monitoring data for operation personnel; the operation failure signal of the sootblower determined by logical judgment is also transmitted to the DCS operation screen through a sootblower operation failure output function block 308. When a sootblower failure occurs, the operation personnel are prompted and processed in time at the first time, so that the problem can be effectively discovered and solved, and further consequences caused by the sootblower operation failure can be avoided.

Description

Technical Field

[0001] The invention relates to the technical field of automatic control of thermal power plants, and in particular to a monitoring control system and method for operating faults of boiler sootblowers in thermal power plants. Background Art

[0002] The boiler is one of the three core systems of a modern thermal power station. The operating safety level of the boiler plays a vital role in the operating safety of the entire power plant. Therefore, ensuring the operating safety of the boiler is an important part of the operation of the power plant. During the combustion process of the boiler, each heating surface will inevitably produce ash and slag. Especially in domestic power plants, the actual coal type used is often quite different from the designed coal type. Some are even low-quality coal types with high moisture content, high ash content, and easy slagging, which causes ash and even slagging on the boiler heating surface, resulting in a decrease in boiler efficiency, and even corrosion of the boiler heating surface and abnormal shutdown, seriously affecting the safe operation of the boiler.

[0003] To solve the above problems, large coal-fired power plant boilers have been equipped with advanced soot blowing equipment for many years. Conventional soot blowing methods include steam soot blowing, sonic soot blowing, gas pulse soot blowing, etc. Steam soot blowing has the widest application. Modern large thermal power plant soot blowing control is generally achieved by DCS control or PLC control.

[0004] The installation of advanced sootblowing equipment in thermal power plants solved the above problems, but due to improper operation of sootblower, some new problems were also brought about. For example, if the sootblower is stuck and other faults are not handled in time, the inside of the sootblower may be burned or even cause boiler tube burst. Summary of the invention

[0005] In order to solve the problems existing in the above-mentioned prior art, the present invention proposes a monitoring control system and method for operation failure of boiler sootblower in thermal power plant. Based on the operation signal of sootblower, a new monitoring control system for operation failure of sootblower is proposed by using the existing DCS function block, and an alarm is given to the operation personnel through the DCS screen to provide guidance for the operation personnel, so that the problem can be effectively discovered and solved, and further consequences caused by operation failure of sootblower are avoided.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A monitoring and control system for operation faults of boiler sootblowers in a thermal power plant, comprising a sootblower operation signal 101 for determining the operation time of the sootblowers, a sootblower operation time reset signal 102 for resetting the operation time of the sootblowers, a timing function block 301 for timing the operation time, a first high / low comparator function block 302 for comparing the operation time of the sootblowers with the set sootblower time, a first OR gate 303 for performing a logic OR judgment on the high / low alarm output of the first high / low comparator function block 302, a second high / low comparator function block 304 for comparing the operation time of the sootblowers with the set time, and a sootblower operation time reset signal 102 for resetting the operation time of the sootblowers. a negation function block 305 for negating the sootblower operation signal 101, a second OR gate function block 306 for performing a logic OR judgment on the negation function block 305 and the high alarm output terminal of the first high / low comparator function block 302, an AND gate function block 307 for performing a logic AND judgment on the output terminals of the first OR gate 303, the second high / low comparator function block 304 and the second OR gate function block 306, a sootblower operation fault output function block 308 for transmitting the sootblower operation fault signal to the DCS operation screen, and a sootblower operation time output function block 309 for transmitting the sootblower operation time signal to the DCS operation screen;

[0008] The sootblower operation signal 101 and the sootblower operation time reset signal 102 are respectively connected to the set end and the reset end of the timing function block 301, the output end of the timing function block 301 is connected to the first high / low comparator function block 302, and the high alarm output end and the low alarm output end of the first high / low comparator function block 302 are both connected to the first OR gate 303; the output end of the timing function block 301 is simultaneously connected to the second high / low comparator function block 304; the sootblower operation signal 101 is simultaneously connected to the negation function block 305, and the output end of the negation function block 305 and the high alarm output end of the first high / low comparator function block 302 are connected to the second OR gate function block 306; the output ends of the first OR gate 303, the second high / low comparator function block 304 and the second OR gate function block 306 are all connected to the AND gate function block 307, the output end of the AND gate function block 307 is connected to the sootblower operation fault output function block 308, and the output end of the timing function block 301 is simultaneously connected to the sootblower operation time output function block 309.

[0009] The present invention provides a method for monitoring and controlling the operation failure of a soot blower in a thermal power plant boiler as follows:

[0010] 1) When the setting end of the timing function block 301 collects the sootblower operation signal 101, the timing function block 301 starts timing, and sends the timing to the DCS operation screen through the sootblower operation time output function block 309 to provide the operator with monitoring;

[0011] 2) At the same time, the output time of the timing function block 301 is connected to the first high / low comparator function block 302. The first high / low comparator function block 302 compares the output time of the timing function block 301 with the set sootblower operation high / low alarm time. When the output time of the timing function block 301 is lower than or higher than the set sootblower operation high / low alarm time, the first OR gate 303 outputs a Boolean value 1 to the AND gate function block 307;

[0012] 3) At the same time, the second high / low comparator function block 304 collects the output time of the timing function block 301, and the low alarm time of the second high / low comparator function block 304 is set to 0.01s to avoid the output of the second high / low comparator function block 304 being a Boolean value 1 when the soot blower is not running, that is, when the output of the output end of the timing function block 301 is 0, and a false alarm is generated;

[0013] 4) The negation function block 305 collects the sootblower operation signal 101. When the sootblower operation signal 101 disappears, the output end of the negation function block 305 outputs a Boolean value 1 and is connected to the second OR gate function block 306. At this time, the sootblower operation ends;

[0014] 5) When the sootblower operation time exceeds the high alarm time of the first high / low comparator function block 302, the first high / low comparator function block 302 outputs a Boolean value 1 as a high alarm and is connected to the second OR gate function block 306;

[0015] 6) When the outputs of the first OR gate 303, the second high / low comparator function block 304 and the second OR gate function block 306 are all Boolean values ​​1, it is determined that the sootblower is operating at a fault, and the sootblower operating fault output function block 308 is input through the output of the AND gate function block 307, and a sootblower fault alarm is displayed on the operation screen to remind the operator to perform further processing;

[0016] 7) When the sootblower operation ends, the operator resets the timing logic through the reset button on the DCS screen, and the sootblower operation time reset signal 102 collected by the DCS is connected to the reset end of the timing function block 301, and the timing time of the timing function block 301 is reset.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] 1. The thermal power plant boiler sootblower operation fault monitoring of the present invention transmits the sootblower operation time obtained by the above logic calculation to the DCS operation screen through the sootblower operation time output function block 309, providing intuitive monitoring data for the operation personnel; the sootblower operation fault signal determined by the logic judgment is also transmitted to the DCS operation screen through the sootblower operation fault output function block 308. When the sootblower fault occurs, the operation personnel are prompted immediately for timely processing.

[0019] 2. Based on the existing sootblower operation signal, the present invention uses the existing DCS function block to build relevant operation logic, calculates the sootblower operation time and provides it to the operating personnel for real-time monitoring, and judges whether the sootblower operation is normal by the calculated operation time. When it is judged that the sootblower operation is abnormal, it is transmitted to the DCS screen to remind the operating personnel to deal with it in time, so as to avoid further accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a connection block diagram of the system of the present invention.

[0021] Figure 2 This is the DCS operation monitoring screen of the present invention in actual application in a certain power plant DETAILED DESCRIPTION

[0022] The present invention will be described in more detail below with reference to the accompanying drawings and specific embodiments.

[0023] A monitoring and control system for operation faults of boiler sootblowers in a thermal power plant, comprising a sootblower operation signal 101 for determining the operation time of the sootblowers, a sootblower operation time reset signal 102 for resetting the operation time of the sootblowers, a timing function block 301 for timing the operation time, a first high / low comparator function block 302 for comparing the operation time of the sootblowers with the set sootblower time, a first OR gate 303 for performing a logic OR judgment on the high / low alarm output of the first high / low comparator function block 302, a second high / low comparator function block 304 for comparing the operation time of the sootblowers with the set time, and a sootblower operation time reset signal 102 for resetting the operation time of the sootblowers. a negation function block 305 for negating the sootblower operation signal 101, a second OR gate function block 306 for performing a logical OR judgment on the negation function block 305 and the high alarm output terminal of the first high / low comparator function block 302, an AND gate function block 307 for performing a logical AND judgment on the output terminals of the first OR gate 303, the second high / low comparator function block 304 and the second OR gate function block 306, a sootblower operation fault output function block 308 for transmitting the sootblower operation fault signal to the DCS operation screen, and a sootblower operation time output function block 309 for transmitting the sootblower operation time signal to the DCS operation screen.

[0024] The sootblower operation signal 101 and the sootblower operation time reset signal 102 are respectively connected to the set end and the reset end of the timing function block 301, the output end of the timing function block 301 is connected to the first high / low comparator function block 302, and the high alarm output end and the low alarm output end of the first high / low comparator function block 302 are both connected to the first OR gate 303; the output end of the timing function block 301 is simultaneously connected to the second high / low comparator function block 304; the sootblower operation signal 101 is simultaneously connected to the negation function block 305, and the output end of the negation function block 305 and the high alarm output end of the first high / low comparator function block 302 are connected to the second OR gate function block 306; the output ends of the first OR gate 303, the second high / low comparator function block 304 and the second OR gate function block 306 are all connected to the AND gate function block 307, and the output end of the AND gate function block 307 is connected to the sootblower operation fault output function block 308. The output end of the timing function block 301 is simultaneously connected to the sootblower operation time output function block 309.

[0025] The method for monitoring and controlling the operation failure of the soot blower of a thermal power plant boiler in the present invention is as follows:

[0026] 1) When the setting end of the timing function block 301 collects the sootblower operation signal 101, the timing function block 301 starts timing and sends the timing to the DCS operation screen through the sootblower operation time output function block 309 for the operator to monitor.

[0027] 2) At the same time, the output time of the timing function block 301 is connected to the first high / low comparator function block 302. The first high / low comparator function block 302 compares the output time of the timing function block 301 with the set sootblower operation high / low alarm time. When the output time of the timing function block 301 is lower than or higher than the set sootblower operation high / low alarm time, the first OR gate 303 outputs a Boolean value 1 to the AND gate function block 307.

[0028] 3) At the same time, the second high / low comparator function block 304 collects the output time of the timing function block 301, and the low alarm time of the second high / low comparator function block 304 is set to 0.01s to avoid the output of the second high / low comparator function block 304 being a Boolean value 1 when the soot blower is not running, that is, when the output of the timing function block 301 is 0, generating a false alarm.

[0029] 4) The negation function block 305 collects the sootblower operation signal 101. When the sootblower operation signal 101 disappears, the output end of the negation function block 305 outputs a Boolean value 1 and is connected to the second OR gate function block 306. At this time, the sootblower operation ends.

[0030] 5) When the sootblower operation time exceeds the high alarm time of the first high / low comparator function block 302 , the first high / low comparator function block 302 outputs a Boolean value 1 as a high alarm and is connected to the second OR gate function block 306 .

[0031] 6) When the output ends of the first OR gate 303, the second high / low comparator function block 304 and the second OR gate function block 306 are all Boolean values ​​1, the soot blower operation failure is determined, and the soot blower operation failure output function block 308 is input through the output end of the AND gate function block 307, and the soot blower failure alarm is displayed on the operation screen to remind the operating personnel to perform further processing.

[0032] 7) When the soot blower operation is completed, the operator shall Figure 2 The reset button on the DCS screen shown resets the timing logic, and the sootblower operation time reset signal 102 collected by the DCS is connected to the reset end of the timing function block 301, and the timing time of the timing function block 301 is reset.

[0033] The above-mentioned method for monitoring the operation failure of the boiler sootblower of a thermal power plant transmits the operation time of the sootblower obtained by the above-mentioned logical calculation to the DCS operation screen through the sootblower operation time output function block 309, so as to provide intuitive monitoring data for the operation personnel; the sootblower operation failure signal determined by the logic judgment is also transmitted to the DCS operation screen through the sootblower operation failure output function block 308. When the sootblower failure occurs, the operation personnel are prompted at the first time for timely processing.

[0034] Example

[0035] For a 660MW unit in a power plant, the sootblower operation signal is measured by the local measuring device and then transmitted to the DCS. Figure 1 The control system shown. The sootblower operation time is transmitted to the DCS operation screen in real time to provide intuitive operation data for the operator. The sootblower operation time is used to determine whether the sootblower is operating at a fault. The fault signal is transmitted to the DCS operation screen in real time to provide prompts for the operator. Practice has proved that the boiler sootblower operation fault monitoring control system and method, based on the existing DCS platform, adopts the existing function block construction logic, can effectively and intuitively provide real-time data for the operator to monitor the sootblower operation status, can determine the sootblower operation fault status and prompt the operator in real time, and has achieved good practical results.

[0036] The DCS platform for implementing the control logic in this embodiment adopts the Symphony Plus system of ABB Company.

Claims

1. A thermal power plant boiler sootblower operation fault monitoring and control system, characterized in that: The invention comprises a sootblower operation signal (101) for determining the sootblower operation time, a sootblower operation time reset signal (102) for resetting the sootblower operation time, a timing function block (301) for timing the operation time, a first high / low comparator function block (302) for comparing the sootblower operation time with the set sootblower time, a first OR gate (303) for performing a logical OR judgment on the high / low alarm output of the first high / low comparator function block (302), a second high / low comparator function block (304) for comparing the sootblower operation time with the set time, and a sootblower operation signal (101) for inverting the sootblower operation signal (101). A negation function block (305), a second OR gate function block (306) for performing a logical OR judgment on the negation function block (305) and a high alarm output end of the first high / low comparator function block (302), an AND gate function block (307) for performing a logical AND judgment on the output end of the first OR gate (303), the second high / low comparator function block (304) and the second OR gate function block (306), a soot blower operation fault output function block (308) for transmitting a soot blower operation fault signal to a DCS operation screen, and a soot blower operation time output function block (309) for transmitting a soot blower operation time signal to a DCS operation screen; The sootblower operation signal (101) and the sootblower operation time reset signal (102) are respectively connected to the set end and the reset end of the timing function block (301); the output end of the timing function block (301) is connected to the first high / low comparator function block (302); the high alarm output end and the low alarm output end of the first high / low comparator function block (302) are both connected to the first OR gate (303); the output end of the timing function block (301) is simultaneously connected to the second high / low comparator function block (304); the sootblower operation signal (101) is simultaneously connected to the inversion function block (305), the output end of the negation function block (305) and the high alarm output end of the first high / low comparator function block (302) are connected to the second OR gate function block (306); the output ends of the first OR gate (303), the second high / low comparator function block (304) and the second OR gate function block (306) are all connected to the AND gate function block (307), the output end of the AND gate function block (307) is connected to the soot blower operation fault output function block (308), and the output end of the timing function block (301) is simultaneously connected to the soot blower operation time output function block (309).

2. The monitoring and control method of the thermal power plant boiler sootblower operation fault monitoring and control system according to claim 1, characterized in that: Here are the steps: 1) When the setting end of the timing function block (301) collects the sootblower operation signal (101), the timing function block (301) starts timing, and sends the timing to the DCS operation screen through the sootblower operation time output function block (309) to the operator for monitoring; 2) At the same time, the output time of the timing function block (301) is connected to the first high / low comparator function block (302), and the first high / low comparator function block (302) compares the output time of the timing function block (301) with the set soot blower operation high / low alarm time. When the output time of the timing function block (301) is lower than or higher than the set soot blower operation high / low alarm time, the first OR gate (303) outputs a Boolean value 1 to the AND gate function block (307); 3) At the same time, the second high / low comparator function block (304) collects the output time of the timing function block (301), and the low alarm time of the second high / low comparator function block (304) is set to 0.01s, so as to avoid the output of the second high / low comparator function block (304) being a Boolean value 1 when the soot blower is not running, i.e. when the output of the output end of the timing function block (301) is 0, causing a false alarm; 4) the negation function block (305) collects the soot blower operation signal (101). When the soot blower operation signal (101) disappears, the output end of the negation function block (305) outputs a Boolean value 1 and is connected to the second OR gate function block (306). At this time, the soot blower operation ends; 5) When the sootblower operation time exceeds the high alarm time of the first high / low comparator function block (302), the first high / low comparator function block (302) outputs a Boolean value of 1 as a high alarm and is connected to the second OR gate function block (306); 6) When the output ends of the first OR gate (303), the second high / low comparator function block (304) and the second OR gate function block (306) are all Boolean values ​​1, it is determined that the soot blower is operating at a fault, and the soot blower operating fault output function block (308) is input through the output end of the AND gate function block (307), and a soot blower fault alarm is displayed on the operation screen to remind the operator to perform further processing; 7) When the sootblower operation is finished, the operator resets the timing logic through the reset button on the DCS screen, and the sootblower operation time reset signal (102) collected by the DCS is connected to the reset end of the timing function block (301), and the timing time of the timing function block (301) is reset to zero.

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