CN217980453U - A water level monitoring and automatic control device for valve pits in thermal power plants - Google Patents

Abstract

The utility model relates to the technical field of valve pit intelligent monitoring, in particular to a valve pit water level monitoring and automatic control device in a thermal power plant. Including liquid level transmitter, programmable logic controller, display device, local sound and light alarm device, alarm signal remote transmission device, valve pit drainage pump and drainage pump power switch; the liquid level transmitter is installed in the valve pit, The liquid level transmitter, display device, local sound and light alarm device and the power switch of the drainage pump are all electrically connected to the programmable logic controller, the alarm signal remote transmission device is electrically connected to the local sound and light alarm device, and the valve pit drainage pump It is electrically connected with the drain pump power switch. Compared with the traditional float level switch, the accuracy of valve pit water level detection can be greatly improved; the use of programmable logic controllers for fault judgment can immediately trigger sound and light alarms when the valve pit water level is in a dangerous working condition, reducing equipment failures Rate.

Description

A water level monitoring and automatic control device for valve pits in thermal power plants

technical field

The utility model relates to the technical field of valve pit intelligent monitoring, in particular to a valve pit water level monitoring and automatic control device in a thermal power plant.

Background technique

At present, the circulating cooling water pipes of most thermal power plants are arranged below the ground, and the relevant electric water inlet valves and electric water outlet valves are arranged in the valve pits below the ground

If there is no monitoring equipment in the water level of the valve pit of the thermal power plant, when encountering flood season or pipeline leakage, water will enter or even accumulate in the valve pit, and there is a risk of "electric valve soaking water". More importantly, once the valve motor is soaked in water, the equipment itself will fail, and the electrical circuit where the electric valve is located will be grounded and the protection will malfunction or refuse to operate, affecting the safe operation of the unit, and even causing personal electric shock.

At present, the water level control device of the valve pit is usually a traditional float level switch, that is, the liquid level rises to the position of the electric contact, and the drainage pump is started, but this kind of control device is very easy to fail. There are three reasons: First, after a long period of use of the water level float switch, the float will gradually adhere to impurities and cause the float to become stuck. After the float is stuck, the reproducibility of the float switch’s setting will deteriorate, and even The floating ball cannot be moved or reset in time; secondly, after the floating ball switch fails, it is generally impossible to judge it immediately, and other judgment conditions are needed for comprehensive judgment; thirdly, the accuracy and reliability of the floating ball switch are unstable.

Therefore, it is urgent to design a valve pit water level monitoring device for thermal power plants, which can accurately control the valve pit water level and reduce the failure rate of equipment.

Utility model content

The purpose of this utility model is to provide a valve pit water level monitoring and automatic control device in a thermal power plant, which collects water level information through two independently installed liquid level transmitters and uses a programmable logic controller for fault judgment. When the water level is in a dangerous working condition, the sound and light alarm will be triggered immediately, and the staff in the centralized control room will be reminded in time to control the water level, which can effectively avoid economic losses caused by untimely fault discovery and reduce the equipment failure rate.

The embodiment of the utility model is realized through the following technical solutions: a thermal power plant valve pit water level monitoring and automatic control device, including a liquid level transmitter, a programmable logic controller, a display device, an on-site sound and light alarm device, and an alarm signal Remote transmission device, valve pit drainage pump and drainage pump power switch;

The liquid level transmitter is installed in the valve pit, the liquid level transmitter, the display device, the local sound and light alarm device and the drain pump power switch are all electrically connected to the programmable logic controller, and the alarm signal is far away The transmission device is electrically connected with the local sound and light alarm device, and the valve pit drainage pump is electrically connected with the power supply switch of the drainage pump.

According to a preferred embodiment, the local sound and light alarm device includes a buzzer, a warning light and a reset button.

According to a preferred embodiment, the alarm signal remote transmission device includes a wireless signal amplifier, a signal receiver, and an audible and visual alarm device.

According to a preferred embodiment, the signal receiver and the sound and light alarm device are installed in the centralized control room, the wireless signal amplifier is electrically connected to the local sound and light alarm device, the wireless signal amplifier is electrically connected to the signal receiver, The signal receiver is electrically connected with the sound and light alarm device.

According to a preferred embodiment, there are two liquid level transmitters.

According to a preferred embodiment, the two liquid level transmitters are installed independently.

According to a preferred embodiment, the two liquid level transmitters are submersible liquid level transmitters.

According to a preferred embodiment, the display device is an LED dot matrix display.

According to a preferred embodiment, the valve pit drainage pump is a submersible sewage pump.

According to a preferred embodiment, the drain pump power switch is a GCK low-voltage drawer switch cabinet.

The technical solution of the embodiment of the utility model has at least the following advantages and beneficial effects: the water level information is collected through two independently installed liquid level transmitters, and compared with the traditional float level switch, the detection efficiency of the valve pit water level can be greatly improved. Accuracy, and it can still work normally when a single measuring point fails, which improves the reliability of the equipment; using a programmable logic controller for fault judgment can immediately trigger an audible and visual alarm when the water level of the valve pit is in a dangerous working condition, and timely Reminding the staff in the central control room and controlling the water level can effectively avoid economic losses caused by untimely fault discovery and reduce equipment failure rates.

Description of drawings

Fig. 1 is a schematic structural diagram of a water level monitoring and automatic control device for a valve pit of a thermal power plant provided by Embodiment 1 of the utility model.

detailed description

In order to make the purpose, technical solutions and advantages of the embodiments of the utility model more clear, the technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the utility model. Obviously, the described The embodiments are some embodiments of the present utility model, but not all embodiments. The components of the embodiments of the invention generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations.

Example 1

Referring to Fig. 1, Fig. 1 shows a schematic structural diagram of a valve pit water level monitoring and automatic control device in a thermal power plant provided by an embodiment of the present invention. The device includes: liquid level transmitter, programmable logic controller, display device, local sound and light alarm device, alarm signal remote transmission device, valve pit drainage pump and drainage pump power switch.

In the embodiment of the utility model, the programmable logic controller adopts Siemens S7-200 SMART EMAE08, including I/O terminals for input and output data, the liquid level transmitter, display device, local sound and light alarm The device and the power supply switch of the drainage pump are electrically connected to the programmable logic controller through the I/O terminal; wherein, the liquid level transmitter is installed in the valve pit to detect the underwater pressure signal of the valve pit and transmit the pressure signal Convert it into an electrical signal, and send the electrical signal to the programmable logic controller through the I/O terminal; the display device is used to receive the electrical signal output by the I/O terminal, and display the current water level signal value;

The local audible and visual alarm device is used to receive the electrical signal output by the I/O terminal, and when the electrical signal sent by the programmable logic controller is a dangerous working condition signal, perform an audible and visual alarm; further, the alarm signal is transmitted remotely The device is electrically connected with the local sound and light alarm device, and performs synchronous sound and light alarm with the local sound and light alarm device; the valve pit drainage pump is electrically connected with the drainage pump power switch;

The power switch of the drainage pump is used to receive the electrical signal output by the I/O terminal, and when the electrical signal sent by the programmable logic controller is a dangerous working condition signal, the control valve pit drainage pump is turned on; when the electrical signal sent by the programmable logic controller is When the electrical signal is a signal to cancel the dangerous working condition, the control valve pit drainage pump is closed.

The working principle of the dangerous working condition signal sent by the programmable logic controller is explained as follows:

The programmable logic controller receives the electrical signal input by the liquid level transmitter through the I/O terminal, obtains the water level signal, and makes a danger judgment based on the water level signal, which specifically includes: comparing the water level signal with the standard high threshold, if it is higher than The standard high threshold is judged as a dangerous working condition, or if the difference between the current water level signal and the water level signal at time N is higher than the preset difference, that is, the rate of water level rise exceeds the maximum output of the valve pit drainage pump, it is judged as a dangerous working condition. In one embodiment, the standard height threshold is set to 1 meter, the time N is set to 10 minutes ago, and the preset difference is set to 0.1 meter. Further, when it is judged to be a dangerous working condition, the electrical signal of the dangerous working condition is output through the I/O terminal. If the dangerous working condition is still in the next moment, the block will be sent repeatedly to control the opening of the valve pit drainage pump for water level control, and Trigger the local sound and light alarm device for alarm, and trigger the alarm signal remote transmission device for synchronous sound and light alarm.

When the water level signal is lower than the standard low threshold, and the difference between the current water level signal and the water level signal at time N is lower than the preset difference, it is determined as a non-dangerous working condition. In one embodiment, the standard low threshold is set to 0.5 meters . In summary, this embodiment uses a programmable logic controller for fault judgment, which can immediately trigger an audible and visual alarm when the water level of the valve pit is in a dangerous working state, and promptly remind the staff in the centralized control room and perform water level control, which can effectively avoid failures in fault discovery. The economic loss caused in time reduces the failure rate of equipment.

Example 2

Different from Embodiment 1, the on-site sound and light alarm device in this embodiment includes a buzzer, a warning light and a reset button; when the programmable logic control judges that the electrical signal is a dangerous working condition, the buzzer and the warning are triggered. The light gives an audible and visual alarm, and the reset button controls the buzzer and warning light to realize the functions of silence and light extinguishing.

Further, in order to realize remote synchronous sound and light alarm, in this embodiment, the alarm signal remote transmission device includes a wireless signal amplifier, a signal receiver, and an sound and light alarm device. The signal receiver and the sound and light alarm device are installed in the central control room, the wireless signal amplifier is electrically connected to the local sound and light alarm device, the wireless signal amplifier is electrically connected to the signal receiver, and the signal receiver is connected to the sound and light alarm device. The light alarm device is electrically connected. In order to make the alarm signal remote transmission device and the local sound and light alarm device perform synchronous sound and light alarm.

Further, there are two liquid level transmitters, and the two liquid level transmitters are installed independently, so that they can still work normally when a single measuring point fails, which improves the reliability of the equipment. In this embodiment, the two liquid level transmitters mentioned above both adopt the drop-in type liquid level transmitter, and the model can be selected as WRT-136. The water level information is collected through two independently installed liquid level transmitters. Compared with the traditional float level switch, the accuracy of the valve pit water level detection can be greatly improved.

Further, the display device is an LED dot matrix display, which displays the received current water level signal value.

Further, the valve pit drainage pump is a submersible sewage pump, which can be selected as a WQ10-10-0.75 submersible sewage pump. The flow rate of the sewage pump is 10m ³ /h, which is controlled by a GCK low-voltage drawer switch cabinet, so as to realize Near remote switching function, when the programmable logic controller judges that the electrical signal is in a dangerous working condition, it will trigger the switch to start the pump; when the programmable logic controller judges that the electrical signal is in a non-dangerous working condition, it will trigger the switch to stop the pump.

The above are only preferred embodiments of the utility model, and are not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present utility model shall be included in the protection scope of the present utility model.

Claims (10)

1. A thermal power plant valve pit water level monitoring and automatic control device is characterized in that it includes a liquid level transmitter, a programmable logic controller, a display device, an on-site sound and light alarm device, an alarm signal remote transmission device, and a valve pit Drain pump and drain pump power switch; The liquid level transmitter is installed in the valve pit, the liquid level transmitter, the display device, the local sound and light alarm device and the drain pump power switch are all electrically connected to the programmable logic controller, and the alarm signal is far away The transmission device is electrically connected with the local sound and light alarm device, and the valve pit drainage pump is electrically connected with the power supply switch of the drainage pump. 2. The valve pit water level monitoring and automatic control device of a thermal power plant according to claim 1, wherein the on-site sound and light alarm device includes a buzzer, a warning light and a reset button. 3. The valve pit water level monitoring and automatic control device of a thermal power plant as claimed in claim 1, wherein said alarm signal remote transmission device includes a wireless signal amplifier, a signal receiver and an audible and visual alarm device. 4. The valve pit water level monitoring and automatic control device of a thermal power plant as claimed in claim 3, wherein the signal receiver and the sound and light alarm device are installed in the centralized control room, and the wireless signal amplifier and the on-site sound and light alarm The alarm device is electrically connected, the wireless signal amplifier is electrically connected to the signal receiver, and the signal receiver is electrically connected to the sound and light alarm device. 5. The valve pit water level monitoring and automatic control device of a thermal power plant according to claim 1, wherein there are two liquid level transmitters. 6. The valve pit water level monitoring and automatic control device of a thermal power plant according to claim 5, wherein the two liquid level transmitters are installed independently. 7. The water level monitoring and automatic control device of a valve pit in a thermal power plant according to claim 6, wherein the two liquid level transmitters are drop-in liquid level transmitters. 8. The valve pit water level monitoring and automatic control device of a thermal power plant according to any one of claims 1 to 7, wherein the display device is an LED dot matrix display. 9. The valve pit water level monitoring and automatic control device of a thermal power plant according to claim 8, wherein the valve pit drainage pump is a submersible sewage pump. 10. The water level monitoring and automatic control device of a valve pit in a thermal power plant according to claim 9, wherein the drain pump power switch is a GCK low-voltage drawer switch cabinet.

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