Steam turbine safety relay control clamping piece

Abstract

A steam turbine safety relay control clamping piece relates to a steam turbine safety control device. The TSI card aims to solve the problems that the safety monitoring response time of an existing TSI card is long, and the whole TSI card is likely to be disabled. The TSI card is characterized in that an acquisition signal input end of a first signal processing unit and an acquisition signal input end of a second signal processing unit are electrically connected with P paths of acquisition signal output channels at the same time; a first state signal output end of the first signal processing unit is electrically connected with a first state signal input end of the second signal processing unit; a second state signal output end of the second signal processing unit is electrically connected with a second state signal input end of the first signal processing unit; a first level signal output end of the first signal processing unit and a second level signal output end of the second signal processing unit are electrically connected with two level signal input ends of the AND operation unit respectively; and the AND operation unit is electrically connected with the control signal input end of the corresponding safety relay.

Description

Technical Field

[0001] The utility model relates to a steam turbine safety control device. Background Art

[0002] The existing TSI (Turbine Supervisory Instrumentation) card uses a combination of an MCU and a CPLD (Complex Programmable Logic Device) for signal acquisition and data processing. The MCU is responsible for the main function implementation, and the CPLD is responsible for auxiliary control. Taking the four-channel signal input TSI card of a large unit as an example, an MCU is required to poll the four-channel acquisition signals and finally control the relay output through the configuration logic.

[0003] However, the polling processing cycle of an MCU for multi-channel acquisition signals is long, and the signal processing cycle is greater than 100ms, which increases the safety monitoring response time of the TSI card; and once the MCU fails due to some unpredictable reasons, the entire TSI card will be disabled, making the multi-channel signal acquisition and relay output uncontrollable. Utility Model Content

[0004] The utility model aims to overcome the problem that the safety monitoring response time of the existing TSI card is long and the entire TSI card is easily disabled, and provides a steam turbine safety relay control card.

[0005] The utility model discloses a steam turbine safety relay control card, comprising a first signal processing unit, a second signal processing unit and an AND operation unit;

[0006] The acquisition signal input end of the first signal processing unit is electrically connected to the P-channel acquisition signal output channel of the steam turbine at the same time; the first signal processing unit can poll and obtain M-channel acquisition signals and generate M status signals in sequence;

[0007] The acquisition signal input end of the second signal processing unit is electrically connected to P acquisition signal output channels at the same time; the second signal processing unit can poll and obtain N acquisition signals and generate N status signals in sequence;

[0008] The M-channel acquisition signal output channel does not overlap with the N-channel acquisition signal output channel, and M+N=P;

[0009] The first state signal output terminal of the first signal processing unit is electrically connected to the first state signal input terminal of the second signal processing unit;

[0010] The second state signal output terminal of the second signal processing unit is electrically connected to the second state signal input terminal of the first signal processing unit;

[0011] A first level signal output terminal of the first signal processing unit and a second level signal output terminal of the second signal processing unit are electrically connected to two level signal input terminals of the operation unit respectively;

[0012] The logic operation level signal output terminal of the AND operation unit is electrically connected to the control signal input terminal of the corresponding safety relay.

[0013] The beneficial effects of the utility model are:

[0014] The utility model discloses a steam turbine safety relay control card, which respectively collects and processes signals through two signal processing units, reduces the signal collection and processing cycle, improves the response speed, shortens the safety response time of the card, and effectively implements a method of two MCUs controlling a common relay. One of the signal processing units is redundantly configured, and even if one signal processing unit fails, it will not cause multi-channel signal collection and relay output to be uncontrolled. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The utility model is a schematic diagram of the electrical structure of a steam turbine safety relay control card. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0017] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0018] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention. Specific implementation method 1

[0020] A steam turbine safety relay control card of this embodiment includes a first signal processing unit 1, a second signal processing unit 2 and an AND operation unit 3;

[0021] The acquisition signal input end of the first signal processing unit 1 is electrically connected to the P-channel acquisition signal output channel of the steam turbine at the same time; the first signal processing unit 1 can poll and obtain M-channel acquisition signals and generate M status signals in sequence;

[0022] The acquisition signal input end of the second signal processing unit 2 is electrically connected to the P acquisition signal output channels at the same time; the second signal processing unit 2 can poll and obtain N acquisition signals and generate N status signals in sequence;

[0023] The M-channel acquisition signal output channel does not overlap with the N-channel acquisition signal output channel, and M+N=P;

[0024] The first state signal output terminal of the first signal processing unit 1 is electrically connected to the first state signal input terminal of the second signal processing unit 2;

[0025] The second state signal output terminal of the second signal processing unit 2 is electrically connected to the second state signal input terminal of the first signal processing unit 1;

[0026] The first level signal output terminal of the first signal processing unit 1 and the second level signal output terminal of the second signal processing unit 2 are electrically connected to the two level signal input terminals of the operation unit 3 respectively;

[0027] The logic operation level signal output terminal of the AND operation unit 3 is electrically connected to the control signal input terminal of the corresponding safety relay.

[0028] Specifically, the steam turbine safety relay control card of this embodiment is a card for controlling the safety relay in the TSI steam turbine safety monitoring system.

[0029] Taking P=4, i.e., a total of four acquisition signal output channels, as an example, the first signal processing unit 1 and the second signal processing unit 2 respectively obtain and process two acquisition signals to achieve redundant four-channel configuration logic control safety relay output.

[0030] The first signal processing unit 1 and the second signal processing unit 2 are both constructed by using Microchip PIC MCUs commonly used in existing cards, and the computing unit 3 is constructed by using circuits such as CD4001 / CD4001B.

[0031] The steam turbine safety relay control card comprises two completely independent first signal processing units 1 and second signal processing units 2. The first signal processing unit 1 and the second signal processing unit 2 modules respectively control two signal acquisition and processing channels (M=N=2), so that the steam turbine safety relay control card has four acquisition and processing channels in total.

[0032] The first signal processing unit 1 collects two acquisition signals of this part and generates a status signal to send to the second signal processing unit 2. At the same time, the second signal processing unit 2 collects two acquisition signals of this part and generates a status signal to send to the first signal processing unit 1, that is, the output status of the two channels of this signal processing unit is used as the input of another signal processing unit, and the two signal processing units mutually obtain the status signals of the four acquisition signals for configuration logic processing. This configuration logic is the configuration logic of the existing TSI processor to process the acquisition signal. The above process is carried out in a polling manner, that is, the two signal processors only process the first status signal of one channel at the same time. For example, the first signal processing unit 1 generates a status signal after collecting the acquisition signal of the first channel, and at the same time, the second signal processing unit 2 generates a second status signal after collecting the acquisition signal of the second channel. Then, the first signal processing unit 1 sends the status signal of the first channel to the second signal processing unit 2, and outputs a first level signal according to the status signal of the first channel. The second signal processing unit 2 outputs a second level signal according to the received status signal of the first channel. The first level signal and the second level signal are ANDed to obtain a logic level signal as the control signal of the corresponding safety relay. Then the second signal processing unit 2 sends the state signal of the second channel to the first signal processing unit 1, and outputs a second level signal according to the state signal of the second channel. The first signal processing unit 1 outputs a first level signal according to the received state signal of the first channel, and the first level signal and the second level signal are ANDed to obtain a logic level signal which is used as the control signal of the corresponding safety relay.

[0033] From the above process, it can be seen that the signal processing unit processes each channel of collected signals separately except for the process of generating level signals, and this processing process takes up the most time. The present device adopts two signal processing units, which can save half of the signal processing time when all the collected signal output channels are evenly divided and the process of generating level signals is ignored.

[0034] The first signal processing unit 1 and the second signal processing unit 2 can use the same type of MCU, and download exactly the same configuration logic (existing sensor signal processing configuration logic) during configuration. Therefore, under normal working conditions, the configuration logic output results (first level signal and second level signal) of the first signal processing unit 1 and the second signal processing unit 2 are also completely consistent, and are sent to the AND operation unit 3 (two-input AND gate) at the same time. The result is isolated to the safety relay through the optical coupling isolation unit 10. As long as one output logic level is 0, the safety relay is closed; the signal processing unit with an output logic level of 1 may crash.

[0035] Based on the hardware characteristics of the first signal processing unit 1 and the second signal processing unit 2, when both are in a non-operating state, that is, a dead state, they both output a high level signal by default.

[0036] The various results are listed below:

[0037] When the first signal processing unit 1 and the second signal processing unit 2 both operate normally:

[0038] The first signal processing unit 1 processes the first acquisition signal and obtains a status signal. If the status signal is normal, the first signal processing unit 1 outputs a low level 0, and similarly, the second signal processing unit 2 outputs a low level 0. After the two low levels 0 are ANDed, a low level 0 is obtained, and the safety relay is controlled to close. If the status signal is abnormal, the first signal processing unit 1 outputs a high level 1, and similarly, the second signal processing unit 2 outputs a high level 1. After the two high levels 1 are ANDed, a high level 1 is obtained, and the safety relay is controlled to open.

[0039] The second signal processing unit 2 processes the second acquisition signal and obtains a status signal. If the status signal is normal, the second signal processing unit 2 outputs a low level 0, and similarly, the first signal processing unit 1 outputs a low level 0. After the two low levels 0 are ANDed, a low level 0 is obtained, and the safety relay is controlled to close. If the status signal is abnormal, the second signal processing unit 2 outputs a high level 1, and similarly, the first signal processing unit 1 outputs a high level 1. After the two high levels 1 are ANDed, a high level 1 is obtained, and the safety relay is controlled to open.

[0040] If the first signal processing unit 1 or the second signal processing unit 2 fails (crashes, etc.), then in this state, the first signal processing unit 1 or the second signal processing unit 2 outputs a high level 1 by default. At this time, if one signal processing unit crashes and the other signal processing unit works normally, the other signal processing unit can take over the signal processing work. The signal processing unit that has not crashed will not change its state after the AND operation regardless of whether it outputs a high level 1 or a low level 0. Therefore, the signal processing unit of Wisky can work normally when the other signal processing unit crashes, and the operator can check the working state of the signal processing unit when one of the signal processing units outputs a high level 1, and handle it in time, and the signal processing unit that works normally can take over the monitoring of all signal acquisition channels. The crash state of the signal processing unit can be detected by setting an additional signal processing unit state monitoring device. Whenever the signal processing unit outputs a high level 1, the signal processing unit is monitored for the crash state, and an alarm is issued after confirming the crash, and all signal acquisition channels are switched to another signal processing unit.

[0041] Therefore, M and N may not be equal, and one of them may be zero. Under the premise that the two signal processors have the same specifications and the number of channels can be evenly divided, M=N can save the polling time to the maximum extent. Under the premise that the number of channels cannot be evenly divided, M=N+1 can also save the polling time to the maximum extent. However, based on other considerations, M and N can be set as needed to achieve the desired effect.

[0042] Since the configuration logic of the safety relay is downloaded to the two signal processing units respectively and is completely consistent, the control output to the safety relay by the first signal processing unit 1 and the second signal processing unit 2 is also completely consistent. The two first signal processing units 1 and the second signal processing units 2 output a high level by default, and the output logic level is high through the pull-up resistor to the two-input AND gate, and is isolated to the safety relay through the optocoupler isolation unit 10. The safety relay protects the disconnected state. When the first signal processing unit 1 and the second signal processing unit 2 have an output low level, the output logic level through the two-input AND gate is also low, and the safety relay is closed. The control principles of the other three safety relays are the same, and finally the two signal processing units control four safety relays. Specific implementation method 2

[0044] This embodiment is a further description of the first embodiment. In this embodiment, it further includes a first serial-to-parallel conversion unit 6, a second serial-to-parallel conversion unit 7, a plurality of first state display units 4 and a plurality of second state display units 5;

[0045] The first state output terminal of the first signal processing unit 1 is electrically connected to the serial input terminal of the first serial-to-parallel conversion unit 6, and the multiple ports of the parallel output terminal of the first serial-to-parallel conversion unit 6 are electrically connected to the display signal input terminals of the multiple first state display units 4 respectively;

[0046] The second state output terminal of the second signal processing unit 2 is electrically connected to the serial input terminal of the second serial-to-parallel conversion unit 7 , and the multiple ports of the parallel output terminal of the second serial-to-parallel conversion unit 7 are electrically connected to the display signal input terminals of the multiple second state display units 5 .

[0047] Specifically, the first serial-to-parallel conversion unit 6 and the second serial-to-parallel conversion unit 7 are both used to convert serial data into parallel data.

[0048] The plurality of first status display units 4 and the plurality of second status display units 5 may both be LED indicator lights.

[0049] Taking the first signal processing unit 1 as an example, the original signal of each acquisition signal channel is an analog signal of a local sensor. After being processed by the first signal processing unit 1, three digital state signals of each analog signal can be obtained, which correspond to a quality state signal, an alarm state signal, and a shutdown state signal. In addition to being stored in the first signal processing unit 1, these three state digital signals are output to the outside in the form of parallel data of LED indicators through the first serial-to-parallel conversion unit 6, as shown in the first state display unit 4 (non-OK light, alarm light, and shutdown light) in the figure.

[0050] The first state output terminal of the first signal processing unit 1 is a parallel port, which outputs three digital state signals in parallel to respectively control the lighting states of the LED indicators.

[0051] In the first signal processing unit 1, the three state digital quantity signals are in the form of serial data and can be regarded as a state signal. The state signal is normal when all state digital quantity signals are 0 (quality state 0, alarm state 0, shutdown state 0). The state signal is abnormal when any state digital quantity signal is not 0 (quality state, alarm state, shutdown state is 1). At the same time, it can be known which state is abnormal by lighting the corresponding LED indicator. Specific implementation method three

[0053] This embodiment is a further explanation of the second embodiment. In this embodiment, the parallel output terminal of the first serial-to-parallel conversion unit 6 is also electrically connected to the first state input terminal of the second signal processing unit 2;

[0054] The parallel output terminal of the second serial-to-parallel conversion unit 7 is also electrically connected to the second state input terminal of the first signal processing unit 1 . Specific implementation method four

[0056] This embodiment is a further description of the third embodiment. In this embodiment, a first pull-up resistor 8 and a second pull-up resistor 9 are further included.

[0057] The first level signal output terminal of the first signal processing unit 1 is also electrically connected to the power supply through the first pull-up resistor 8 ; the second level signal output terminal of the second signal processing unit 2 is also electrically connected to the power supply through the second pull-up resistor 9 .

[0058] Specifically, the pull-up resistor can ensure that the first level signal output terminal and the second level signal output terminal of the first signal processing unit 1 or the second signal processing unit 2 are stably pulled to a high level without active driving. This avoids the signal line being in an uncertain state, especially when the output of the signal processing unit enters a high impedance state or during signal switching.

[0059] At the same time, the pull-up resistor can limit the current flowing through the input terminal of the AND operation unit 3 to prevent excessive current from damaging the AND operation unit 3 or other downstream circuits. Specific implementation method five

[0061] This embodiment is a further description of the fourth embodiment. In this embodiment, an optical coupling isolation unit 10 is also included;

[0062] The AND operation unit 3 sends the level signal obtained by operation to the control signal input terminal of the safety relay through the optical coupling isolation unit 10.

[0063] Specifically, the optocoupler isolation unit 10 provides a physical isolation to prevent high voltage or high current from one side of the safety relay (usually a high voltage or high power environment) from affecting the low voltage, low power side circuit where the operation unit 3 is located, thereby protecting sensitive electronic equipment.

[0064] The optocoupler isolation unit 10 can also convert the logic level signal into a current signal sufficient to drive the relay, thereby realizing the conversion from a small signal to a large signal.

[0065] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments, and other arrangements may be designed without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that different dependent claims and features herein may be combined in a manner different from that described in the original claims. It may also be understood that the features described in conjunction with the individual embodiments may be used in other embodiments.

Claims

1. A steam turbine safety relay control card, characterized in that: It comprises a first signal processing unit (1), a second signal processing unit (2) and an AND operation unit (3); The acquisition signal input end of the first signal processing unit (1) is electrically connected to the P-channel acquisition signal output channel of the steam turbine at the same time; the first signal processing unit (1) is capable of polling and acquiring M-channel acquisition signals and sequentially generating M status signals; The acquisition signal input end of the second signal processing unit (2) is electrically connected to the P acquisition signal output channels at the same time; the second signal processing unit (2) is capable of polling and acquiring N acquisition signals and sequentially generating N status signals; The M-channel acquisition signal output channel does not overlap with the N-channel acquisition signal output channel, and M+N=P; The first state signal output terminal of the first signal processing unit (1) is electrically connected to the first state signal input terminal of the second signal processing unit (2); The second state signal output terminal of the second signal processing unit (2) is electrically connected to the second state signal input terminal of the first signal processing unit (1); The first level signal output end of the first signal processing unit (1) and the second level signal output end of the second signal processing unit (2) are electrically connected to the two level signal input ends of the AND operation unit (3) respectively; The logic operation level signal output terminal of the AND operation unit (3) is electrically connected to the control signal input terminal of the corresponding safety relay.

2. A steam turbine safety relay control card according to claim 1, characterized in that: It also includes a first serial-to-parallel conversion unit (6), a second serial-to-parallel conversion unit (7), a plurality of first state display units (4) and a plurality of second state display units (5); The first state output end of the first signal processing unit (1) is electrically connected to the serial input end of the first serial-to-parallel conversion unit (6), and the plurality of ports of the parallel output end of the first serial-to-parallel conversion unit (6) are respectively electrically connected to the display signal input ends of the plurality of first state display units (4); The second state output end of the second signal processing unit (2) is electrically connected to the serial input end of the second serial-to-parallel conversion unit (7), and the multiple ports of the parallel output end of the second serial-to-parallel conversion unit (7) are respectively electrically connected to the display signal input ends of the multiple second state display units (5).

3. A steam turbine safety relay control card according to claim 2, characterized in that: The parallel output terminal of the first serial-to-parallel conversion unit (6) is also electrically connected to the first state input terminal of the second signal processing unit (2); The parallel output terminal of the second serial-to-parallel conversion unit (7) is also electrically connected to the second state input terminal of the first signal processing unit (1).

4. A steam turbine safety relay control card according to claim 3, characterized in that: It also includes a first pull-up resistor (8) and a second pull-up resistor (9); The first level signal output end of the first signal processing unit (1) is also electrically connected to a power supply via a first pull-up resistor (8); and the second level signal output end of the second signal processing unit (2) is also electrically connected to a power supply via a second pull-up resistor (9).

5. A steam turbine safety relay control card according to claim 4, characterized in that: It also includes an optical coupling isolation unit (10); The AND operation unit (3) sends the level signal obtained by operation to the control signal input end of the safety relay through the optical coupling isolation unit (10).

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