An AST tripping circuit for a DCS integrated ETS system

Abstract

An AST tripping circuit for an integrated DCS-ETS system. The control circuits for AST solenoid valves 1 / 2 / 3 / 4 and the ETS overspeed protection control circuit are on the same logic component board, exhibiting extremely high integration. Failure of a single component can easily lead to unscheduled unit shutdowns. This invention includes an ETS speed card and an ETS 110% overspeed 3-out-of-2 protection hard circuit. Its key feature is that each ETS speed card outputs an overspeed protection signal, forming two sets of ETS overspeed protection signals, which are input to two logic components KB434D, forming the ETS 110% overspeed 3-out-of-2 protection hard circuit; the four AST solenoid valve soft logic tripping circuits are distributed within the logic component KB434D. This invention is used for AST tripping in an integrated ETS system.

Description

Technical Field

[0001] This utility model relates to an AST tripping circuit in a DCS integrated ETS system. Technical Background

[0002] When the 680MW supercritical thermal power unit underwent domestic DCS retrofitting, the ETS system (Emergency Turbine Trip System) was simultaneously integrated. Its AST trip circuit consists of highly integrated power supply boards, logic boards, and trip component boards. The trip circuit control is performed using the power supply board switching function and a single logic component board, without achieving decentralized configuration, which poses a risk of protection malfunction. At the same time, due to the centralized function, if a single component in a certain type of component board fails, the maintenance and replacement work poses an extremely high safety risk. If not handled properly, it can easily cause unplanned unit shutdown.

[0003] The AST solenoid valves of this thermal power unit are configured in a series-parallel structure, that is, AST solenoid valve 1 and AST solenoid valve 3 are connected in parallel, AST solenoid valve 2 and AST solenoid valve 4 are connected in parallel, and then connected in series. The control commands for AST solenoid valves 1 and 3 and AST solenoid valves 2 and 4 are powered by two power supplies output from the power switching device. If the switching module fails, AST solenoid valves 1 / 2 / 3 / 4 will lose power simultaneously, causing unscheduled unit shutdown. At the same time, the control circuits of AST solenoid valves 1 / 2 / 3 / 4 and the ETS overspeed protection control circuit are on the same logic component board, with a very high degree of integration. The safety risk caused by the failure of a single component can easily lead to unscheduled unit shutdown. Utility Model Content

[0004] The purpose of this invention is to solve the above-mentioned technical problems and provide an AST tripping circuit for an integrated DCS ETS system.

[0005] To address the aforementioned shortcomings, this utility model adopts the following technical solution: An AST tripping circuit for a DCS integrated ETS system comprises: an ETS speed card and an ETS overspeed 110% three-out-of-two protection hard circuit. Each ETS speed card outputs an overspeed protection signal to form two sets of ETS overspeed protection signals, which are input to two logic components KB434D to form an ETS overspeed 110% three-out-of-two protection hard circuit. The four AST solenoid valve soft logic trip circuits are distributed in the logic component KB434D.

[0006] The aforementioned DCS integrated ETS system AST trip circuit includes two AST solenoid valve soft logic trip circuits in the first logic component KB434D, and the other two AST solenoid valve soft logic trip circuits in the second logic component KB434D. Beneficial effects

[0007] 1. By adding a logic component KB434D, this utility model distributes the trip control circuit, reducing the risk of centralized control caused by a single logic component, and effectively avoiding protection maloperation caused by a single equipment failure.

[0008] 2. This utility model enhances the stability of the power system by changing the function of the power supply component KB434A and replacing the original redundant switching function with its more reliable extended function; at the same time, the power supply is increased from 2 to 4, and the reliability is effectively improved. Attached Figure Description

[0009] Figure 1 This is the circuit diagram of the first logic component, KB434D. Figure 2 This is the circuit diagram of the second logic component, KB434D. Figure 3 This is the first AST solenoid valve shutdown circuit diagram; Figure 4 This is the second AST solenoid valve shutdown circuit diagram; Figure 5 This is the circuit diagram for the third AST solenoid valve shutdown. Figure 6 This is the circuit diagram for the fourth AST solenoid valve shutdown. Figure 7 This is the circuit diagram of the first AST power distribution component; Figure 8 This is the circuit diagram of the second AST power distribution component. Detailed Implementation

[0010] An AST tripping circuit for a DCS integrated ETS system comprises: an ETS speed card and an ETS overspeed 110% three-out-of-two protection hard circuit. Each ETS speed card outputs an overspeed protection signal to form two sets of ETS overspeed protection signals, which are input to two logic components KB434D to form an ETS overspeed 110% three-out-of-two protection hard circuit. The four AST solenoid valve soft logic trip circuits are distributed in the logic component KB434D.

[0011] The aforementioned DCS integrated ETS system AST trip circuit includes two AST solenoid valve soft logic trip circuits in the first logic component KB434D, and the other two AST solenoid valve soft logic trip circuits in the second logic component KB434D.

[0012] KB434A (Power Supply Board, one unit): 1. Provide two independent DC24V control power supplies for the two KB434D component boards.

[0013] 2. Provide two independent AC220V solenoid valve drive power supplies for the KB434E component board (one supplying AST1 / AST3 and the other supplying AST2 / AST4) to prevent system shutdown due to power loss in one circuit.

[0014] KB434D (ETS logic component board, two pieces): 1. Function 1 (Soft Logic): Receives and processes ETS trip signals (such as axial displacement, low vacuum, etc.) from the card and outputs the corresponding DC24V control signal.

[0015] 2. Function 2 (Overspeed Logic): Receives the "110% overspeed" normally closed contact signal from three speed measuring cards, builds a three-out-of-two voting circuit through internal relays, and outputs a DC24V control signal.

[0016] KB434E (ETS Shutdown Component Board, one piece): Core function: Serves as the final execution unit for all stop signals.

[0017] 1. Receives DC24V signal from KB434D board to drive internal intermediate relays (ETSTJx, OETJx).

[0018] 2. Receive hard-wired signals from the manual buttons on the control panel.

[0019] Based on different control methods, there are three types: Composition of the gain / loss circuit of the AST solenoid valve: 1. Soft logic control 2. Tachometer card 110% overspeed 3. Control panel buttons The solenoid valve is energized: AST1 solenoid valve (with): ① Soft logic not activated: The logic in ETS did not trigger the AST1 solenoid valve activation signal. ETS main cabinet - A06 slot - 1 channel is TRUE. KB434D1 component board KB434D1-1J29, 30 control voltage output DC24V. Relay ETSTJ1 in KB434E component board is energized, and the normally open contact of relay ETSTJ1 is closed.

[0020] ② Tachometer card does not activate at 110% speed: The three normally closed contacts (110% overspeed disconnect) of the three tachometer cards in the ETS cabinet are connected sequentially to KB434D1-1J1,2, KB434D1-1J3,4, and KB434D1-1J5,6. Relays OEJ1, OEJ2, and OEJ3 in the KB434D1 component board are energized (two sets of normally open contacts in the three relays are connected in series and then in parallel to form a three-out-of-two circuit). The normally open contacts of the three relays close, and the control voltage output of KB434D1-1J21 and 22 in the KB434D1 component board is DC24V. Relay OETJ1 in the KB434E component board is energized, and the normally open contact of relay OETJ1 closes.

[0021] ③ Control panel buttons not activated: The normally closed contacts of the two control panel buttons are connected in parallel to KB434E-2J7,8 and are not pressed.

[0022] When the normally open contact of ETSTJ1 is closed, the normally open contact of relay OETJ1 is closed and neither of the two buttons on the control panel is pressed, KB434E-2J9,10 outputs AC220V to the local AST1 solenoid valve. AST2 solenoid valve (with): ① Soft logic not activated: The logic in ETS did not trigger the AST2 solenoid valve activation signal. ETS main cabinet - B03 slot - 1 channel is TRUE. KB434D2 component board KB434D2-1J31, 32 control voltage output DC24V. Relay ETSTJ2 in KB434E component board is energized, and the normally open contact of relay ETSTJ2 is closed.

[0023] ② Tachometer card does not activate at 110% speed: The three normally closed contacts (110% overspeed disconnect) of the three speed measuring cards in the ETS cabinet are connected sequentially to KB434D2-1J1,2, KB434D2-1J3,4, and KB434D2-1J5,6. Relays OEJ1, OEJ2, and OEJ3 in the KB434D2 component board are energized (two sets of normally open contacts in the three relays are connected in series and then in parallel to form a three-out-of-two circuit). The normally open contacts of the three relays close, and the control voltage output of KB434D2 component board KB434D2-1J23,24 is DC24V. Relay OETJ2 in the KB434E component board is energized, and the normally open contact of relay OETJ2 closes.

[0024] ③ Control panel buttons not activated: The normally closed contacts of the two control panel buttons are connected in parallel to KB434E-2J17,18 and are not pressed.

[0025] When the normally open contact of ETSTJ2 is closed, the normally open contact of relay OETJ2 is closed and neither of the two buttons on the control panel is pressed, KB434E-2J19,20 outputs AC220V to the local AST2 solenoid valve. AST3 solenoid valve (with): ① Soft logic not activated: The logic in ETS did not trigger the AST3 solenoid valve activation signal. ETS main cabinet - C06 slot - 1 channel is TRUE. KB434D1 component board KB434D1-1J33, 34 control voltage output DC24V. Relay ETSTJ3 in KB434E component board is energized, and the normally open contact of relay ETSTJ3 is closed.

[0026] ② Tachometer card does not activate at 110% speed: The three normally closed contacts (110% overspeed disconnect) of the three speed measuring cards in the ETS cabinet are connected sequentially to KB434D1-1J1,2, KB434D1-1J3,4, and KB434D1-1J5,6. Relays OEJ1, OEJ2, and OEJ3 in the KB434D1 component board are energized (two sets of normally open contacts in the three relays are connected in series and then in parallel to form a three-out-of-two circuit). The normally open contacts of the three relays close, and the control voltage output of KB434D1-1J25,26 in the KB434D1 component board is DC24V. Relay OETJ3 in the KB434E component board is energized, and the normally open contact of relay OETJ3 closes.

[0027] ③ Control panel buttons not activated: The normally closed contacts of the two control panel buttons are connected in parallel to KB434E-2J27,28 and are not pressed.

[0028] When the normally open contact of ETSTJ3 is closed, the normally open contact of relay OETJ3 is closed and neither of the two buttons on the control panel is pressed, KB434E-2J29,30 outputs AC220V to the local AST3 solenoid valve.

[0029] AST4 solenoid valve (with): ① Soft logic not activated: The logic in ETS did not trigger the AST4 solenoid valve activation signal. ETS main cabinet - B04 slot - 1 channel is TRUE. KB434D2 component board KB434D2-1J33, 34 control voltage output DC24V. Relay ETSTJ4 in KB434E component board is energized, and the normally open contact of relay ETSTJ2 is closed.

[0030] ② Tachometer card does not activate at 110% speed: The three normally closed contacts (110% overspeed disconnect) of the three tachometer cards in the ETS cabinet are connected sequentially to KB434D2-1J1,2, KB434D2-1J3,4, and KB434D2-1J5,6. Relays OEJ1, OEJ2, and OEJ3 in the KB434D2 component board are energized (two sets of normally open contacts in the three relays are connected in series and then in parallel to form a three-out-of-two circuit). The normally open contacts of the three relays close, and the control voltage output of KB434D2-1J27,28 in the KB434D2 component board is DC24V. Relay OETJ4 in the KB434E component board is energized, and the normally open contact of relay OETJ4 closes.

[0031] ③ Control panel buttons not activated: The normally closed contacts of the two control panel buttons are connected in parallel to KB434E-2J37,38 and are not pressed.

[0032] When the normally open contact of ETSTJ4 is closed, the normally open contact of relay OETJ4 is closed and neither of the two buttons on the control panel is pressed, KB434E-2J39,40 outputs AC220V to the local AST4 solenoid valve.

[0033] Solenoid valve de-energized: AST1 solenoid valve (or): ① Soft logic action: The logic in ETS triggers the AST1 solenoid valve action signal. The ETS main cabinet - A06 slot - 1 channel is FALSE. The KB434D1 component board KB434D1-1J29, 30 has no control voltage output. The relay ETSTJ1 in the KB434E component board is de-energized, and the normally open contact of the relay ETSTJ1 is opened.

[0034] ② 110% Speed ​​Measurement Card Activation: The three speed measurement cards in the ETS cabinet output three normally closed contacts (disconnected due to the 110% speed measurement activation), which are sequentially connected to KB434D1-1J1,2, KB434D1-1J3,4, and KB434D1-1J5,6. Relays OEJ1, OEJ2, and OEJ3 in the KB434D1 component board are de-energized (two sets of normally open contacts in the three relays are connected in series and then in parallel to form a three-out-of-two circuit). The normally open contacts of the three relays open, and there is no control voltage output from KB434D1 component board KB434D1-1J21,22. Relay OETJ1 in the KB434E component board is de-energized, and the normally open contact of relay OETJ1 opens.

[0035] ③ Manual tripping via control panel buttons: The normally closed contacts of the two control panel buttons are connected in parallel to KB434E-2J7,8. When both buttons are pressed, the normally closed contacts open.

[0036] If the normally open contact of ETSTJ1 is open, or the normally open contact of relay OETJ1 is open, or both buttons on the control panel are pressed, KB434E-2J9 and 10 will have no output, and the local AST1 solenoid valve will lose power.

[0037] AST2 solenoid valve (or): ① Soft logic action: The logic in ETS triggers the AST2 solenoid valve action signal. The channel of ETS main cabinet-B03 slot-1 is FALSE. The KB434D2 component board KB434D2-1J31,32 has no control voltage output. The relay ETSTJ2 in the KB434E component board is de-energized, and the normally open contact of the relay ETSTJ2 is open.

[0038] ② 110% Speed ​​Card Action: The three speed cards in the ETS cabinet output three normally closed contacts (110% overspeed disconnect) which are connected sequentially to KB434D2-1J1,2, KB434D2-1J3,4, and KB434D2-1J5,6. Relays OEJ1, OEJ2, and OEJ3 in the KB434D2 component board are de-energized (two sets of normally open contacts in the three relays are connected in series and then in parallel to form a three-out-of-two circuit). The normally open contacts of the three relays open, and there is no control voltage output from KB434D2 component board KB434D2-1J23,24. Relay OETJ2 in the KB434E component board is de-energized, and the normally open contact of relay OETJ2 opens.

[0039] ③ Manual tripping via control panel buttons: The normally closed contacts of the two control panel buttons are connected in parallel to KB434E-2J17,18. When both buttons are pressed, the normally closed contacts open.

[0040] If the normally open contact of ETSTJ2 is open, or the normally open contact of relay OETJ2 is open, or both buttons on the control panel are pressed, KB434E-2J19,20 will have no output, and the local AST2 solenoid valve will lose power.

[0041] AST3 solenoid valve (or): ① Soft logic action: The logic triggers the AST3 solenoid valve action signal in the ETS main cabinet - C06 slot - 1 channel is FALSE, the KB434D1 component board KB434D1-1J33,34 has no control voltage output, the relay ETSTJ3 in the KB434E component board is de-energized, and the normally open contact of the relay ETSTJ3 is open.

[0042] ② 110% Speed ​​Card Action: The three speed cards in the ETS cabinet output three normally closed contacts (110% overspeed disconnect) which are sequentially connected to KB434D1-1J1,2, KB434D1-1J3,4, and KB434D1-1J5,6. Relays OEJ1, OEJ2, and OEJ3 in the KB434D1 component board are de-energized (two sets of normally open contacts in the three relays are connected in series and then in parallel to form a three-out-of-two circuit). The normally open contacts of the three relays open, and there is no control voltage output from KB434D1 component board KB434D1-1J25,26. Relay OETJ3 in the KB434E component board is de-energized, and the normally open contact of relay OETJ3 opens.

[0043] ③ Manual tripping via control panel buttons: The normally closed contacts of the two control panel buttons are connected in parallel to KB434E-2J27,28. When both buttons are pressed, the normally closed contacts open.

[0044] If the normally open contact of ETSTJ3 is open, or the normally open contact of relay OETJ3 is open, or both buttons on the control panel are pressed, KB434E-2J29,30 will have no output and the local AST3 solenoid valve will lose power.

[0045] AST4 solenoid valve (or): ① Soft logic action: The logic in ETS triggers the AST4 solenoid valve action signal. The ETS main cabinet -B04 slot -1 channel is FALSE. The KB434D2 component board KB434D2-1J33,34 has no control voltage output. The relay ETSTJ4 in the KB434E component board is de-energized, and the normally open contact of the relay ETSTJ2 is opened.

[0046] ② 110% Speed ​​Card Activation: The three speed cards in the ETS cabinet output three normally closed contacts (110% overspeed disconnect) which are sequentially connected to KB434D2-1J1,2, KB434D2-1J3,4, and KB434D2-1J5,6. Relays OEJ1, OEJ2, and OEJ3 in the KB434D2 component board are de-energized (two sets of normally open contacts in the three relays are connected in series and then in parallel to form a three-out-of-two circuit). The normally open contacts of the three relays open, and there is no control voltage output from KB434D2 component board KB434D2-1J27,28. Relay OETJ4 in the KB434E component board is de-energized, and the normally open contact of relay OETJ4 opens.

[0047] ③ Manual tripping via control panel buttons: The normally closed contacts of the two control panel buttons are connected in parallel to KB434E-2J37,38. When both buttons are pressed, the normally closed contacts open.

[0048] If the normally open contact of ETSTJ4 is open, or the normally open contact of relay OETJ4 is open, or both buttons on the control panel are pressed, KB434E-2J39,40 will have no output and the local AST4 solenoid valve will lose power.

Claims

1. A DCS integrated ETS system AST trip circuit, consisting of: The ETS speed card and ETS overspeed 110% two-out-of-two protection hard circuit, characterized in that: each of the ETS speed cards further outputs an overspeed protection signal, forming two groups of ETS overspeed protection signals, which are input into two logic components KB434D, forming an ETS overspeed 110% two-out-of-two protection hard circuit; The four AST solenoid valve soft logic trip circuits are distributed into the logic components KB434D.

2. The DCS integrated ETS system AST trip circuit of claim 1 wherein the two The AST solenoid valve soft logic trip circuit is in the first logic component KB434D, and the other two AST solenoid valve soft logic trip circuits are in the second logic component KB434D.

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