A control method and storage medium for a fire-fighting fluid supply system

Abstract

The present invention provides a control method and storage medium for a fire-fighting fluid supply system, belonging to the field of firefighting technology. The fire-fighting fluid supply system includes: a fire pump; a fire-fighting nozzle; a fluid supply pipe; a valve; a command input module; and a controller. The control method comprises the following steps: the controller reads a firefighter's command from the command input module at a preset time interval Δt, executes a control operation, and records the control operation; t = 0 is set as the time the fire-fighting fluid supply system is powered on; then, at time t = iΔt, the controller executes a control operation according to a specified rule based on the command at that time, the valve opening, the speed of the adjustable motor, and the control operation record since power-on. The present invention achieves flexible, rapid, efficient, and reliable regulation of the spray flow rate and spray speed while saving operating energy and extending operating life.

Description

Technical Field

[0001] The present invention relates to the field of fire protection technology, and in particular to a control method for a fire protection fluid supply system and a storage medium thereof. Background Art

[0002] Firefighting fluid supply systems are crucial firefighting equipment. Centrifugal pumps typically serve as these pumps, pumping liquid from a reservoir and dispensing it through a supply pipe and then a firefighting nozzle. During operation, firefighting fluid supply systems often require flexible adjustment of the spray flow rate and velocity based on on-site conditions. For example, when a fire is well under control, the spray flow rate can be reduced; however, when the fire is far from the nozzle, increasing the spray velocity to achieve a longer spray range is crucial. Currently available technical solutions lack a comprehensive and optimal adjustment scheme.

[0003] In view of this, the present invention provides a new solution to solve the above problems. Summary of the Invention

[0004] The purpose of the present invention is to provide a control method and storage medium for a fire-fighting fluid supply system. Based on this technical solution, flexible, rapid, efficient and stable adjustment of the spray flow rate and spray speed can be achieved, and the system operating energy consumption can be saved as much as possible and the system operating life can be extended.

[0005] The above technical objectives of the present invention are achieved through the following technical solutions.

[0006] A control method for a fire-fighting liquid supply system is applied to the fire-fighting liquid supply system, the fire-fighting liquid supply system comprising:

[0007] A fire pump, wherein the fire pump is provided with an adjustable speed motor, and the adjustable speed motor is used to drive the impeller of the fire pump to rotate;

[0008] Fire lance head;

[0009] a liquid supply pipe connected between the fire lance head and the fire pump outlet;

[0010] A valve, which is mounted on the fire-fighting gun head and is used to adjust the flow area of the fire-fighting gun head spraying liquid to the outside;

[0011] An instruction input module, the instruction input module is used to receive an adjustment instruction of the spray flow rate and / or the spray speed;

[0012] A controller, the controller being electrically connected to the adjustable speed motor, the valve, and the instruction input module, and configured to control the speed of the adjustable speed motor and the opening of the valve according to instructions on the instruction input module;

[0013] The control method comprises the following steps:

[0014] The controller reads the firefighter's command from the command input module once every preset time interval Δt, performs a control operation and records the control operation;

[0015] Let t=0 be the startup time of the fire-fighting fluid supply system. Then, at time t=iΔt, control operations are performed according to the specified rules based on the instructions at that time, valve opening, adjustable speed motor speed, and control operation records since startup.

[0016] It is further preferred that: the command input module is arranged on the fire fighting gun head.

[0017] Further preferably, the valve is an electric regulating valve.

[0018] More preferably, the fire pump is a centrifugal pump.

[0019] It is further preferred that: the specified rules include rules corresponding to when the instruction at this moment is to increase the spray flow rate, when the instruction at this moment is to increase the spray speed, when the instruction at this moment is to reduce the spray flow rate, and when the instruction at this moment is to reduce the spray speed.

[0020] More preferably:

[0021] i. When the instruction at this moment is to increase the spray flow rate:

[0022] If the valve opening K at this moment i <Valve opening maximum threshold K max , and the number of valve opening increase control operations performed from t=(ia)Δt to t=(i-1)Δt is not a times, then the valve opening is increased by ΔK;

[0023] If the valve opening K at this moment i = Maximum valve opening threshold K max , or the number of valve opening increase control operations performed from t=(ia)Δt to t=(i-1)Δt is a times, then the speed of the adjustable speed motor is increased by Δn;

[0024] ii. When the instruction at this moment is to increase the spray speed:

[0025] If the valve opening K at this moment i > Minimum valve opening threshold K min , and the number of valve opening reduction control operations performed from t=(ib)Δt to t=(i-1)Δt is not b times, then the valve opening is reduced by ΔK;

[0026] If the valve opening K at this moment i = minimum valve opening threshold Kmin , or the number of valve opening reduction control operations executed from t=(ib)Δt to t=(i-1)Δt is b times, then the speed of the adjustable speed motor is increased by Δn;

[0027] iii. When the instruction at this moment is to reduce the spray flow rate:

[0028] If the speed of the adjustable motor n i >Minimum threshold value n for adjustable speed motor min , and the number of speed reduction control operations of the adjustable-speed motor executed from time t=(ic)Δt to time t=(i-1)Δt is not c times, then the speed of the adjustable-speed motor is reduced by Δn;

[0029] If the speed of the adjustable motor n i = Minimum threshold value of adjustable speed motor speed n min , or the number of speed control operations for reducing the speed of the adjustable speed motor executed from time t=(ic)Δt to time t=(i-1)Δt is c times, then the valve opening is reduced by ΔK;

[0030] iv. When the instruction at this moment is to reduce the spray speed:

[0031] If the speed of the adjustable motor n i >Minimum threshold value n for adjustable speed motor min , and the number of speed reduction control operations of the adjustable speed motor executed from time t=(id)Δt to time t=(i-1)Δt is not d times, then the speed of the adjustable speed motor is reduced by Δn;

[0032] If the speed of the adjustable motor n i = Minimum threshold value of adjustable speed motor speed n min , or the number of speed control operations of reducing the adjustable speed motor executed from time t=(id)Δt to time t=(i-1)Δt is d times, then the valve opening is increased by ΔK;

[0033] The above i, a, b, c, and d are all positive integers, Δn is the motor speed change in a single motor speed control operation, and ΔK is the valve opening change in a single valve opening control operation.

[0034] Further preferably, if according to the specified rule, the speed of the adjustable speed motor after a speed control operation is greater than the maximum speed threshold value n of the adjustable speed motor max Or less than the minimum threshold value n of the adjustable speed motor speed min , then the actual speed control operation of the adjustable speed motor is to the maximum speed threshold value n of the adjustable speed motor max Or the minimum speed threshold of the adjustable motor n min ;

[0035] If, according to the specified rules, the valve opening after a certain valve opening control operation is greater than the maximum valve opening threshold K max Or less than the minimum valve opening threshold K min , then the valve opening is actually controlled to the maximum valve opening threshold K max Or the minimum threshold value of valve opening K min .

[0036] It is further preferred that: at the same time, the controller only receives one of the two instructions of adjusting the spray flow rate of the fire-fighting liquid supply system and adjusting the spray speed of the fire-fighting liquid supply system;

[0037] If the firefighter inputs two instructions at the same time, namely, adjusting the spray flow rate of the fire-fighting fluid supply system and adjusting the spray speed of the fire-fighting fluid supply system, the instruction will be decomposed into two instructions. The instruction of the same type as the previous instruction will be executed first, and then the instruction of a different type from the previous instruction will be executed.

[0038] A storage medium is provided, which is a computer-readable storage medium. A control program of a fire protection fluid supply system control method is stored on the storage medium. When the control program of the fire protection fluid supply system control method is executed by a processor, the steps of the fire protection fluid supply system control method are implemented.

[0039] In summary, the present invention has the following beneficial effects:

[0040] After the liquid supply system receives the on-site spray flow and spray speed adjustment instructions from the firefighters, the present invention can comprehensively consider factors such as the operating energy consumption and operating life loss of the liquid supply system, and pay full attention to minimizing the significant impact of the adjustment on another working state in a short period of time when adjusting one working state, avoiding drastic fluctuations in output, and at the same time, the adjustment method is more flexible, fast, efficient and stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A schematic diagram of the fire-fighting fluid supply system according to an embodiment of the present invention;

[0042] Figure 2 This is a diagram showing the regulation principle of the fire-fighting fluid supply system in an embodiment of the present invention.

[0043] In the figure, 1. Fire pump; 2. Adjustable speed motor; 3. Liquid supply pipe; 4. Fire gun head; 5. Valve; 6. Controller; 7. Command input module. DETAILED DESCRIPTION

[0044] The present invention will be further described below with reference to the accompanying drawings.

[0045] A control method for a fire-fighting fluid supply system and a storage medium thereof, such as Figure 1As shown, the firefighting fluid supply system includes a fire pump 1, a fire lance head 4, a fluid supply pipe 3, a valve 5, a command input module 7, and a controller 6. Fire pump 1 is equipped with an adjustable-speed motor 2, which serves as its core drive component and drives the impeller of fire pump 1. The fluid supply pipe 3 is connected to the fire lance head 4 and the outlet of fire pump 1, respectively. This allows the fire pump 1 to draw fluid from the reservoir, then transport it through the fluid supply pipe 3 to the fire lance head 4, where it is then sprayed outward. A valve 5 is mounted on the fire lance head 4 and is used to adjust the flow area of the fluid sprayed outward from the fire lance head 4.

[0046] The instruction input module 7 is used to receive adjustment instructions for the liquid spraying flow rate and / or liquid spraying speed.

[0047] Preferably, the adjustment instruction includes increasing or decreasing the liquid spraying flow rate and increasing or decreasing the liquid spraying speed.

[0048] The controller 6 is electrically connected to the adjustable speed motor 2, the valve 5 and the instruction input module 7. The controller 6 is used to read the adjustment instructions on the instruction input module 7 and control the speed of the adjustable speed motor 2 and the opening of the valve 5 according to the adjustment instructions.

[0049] Preferably, the command input module 7 is provided on the fire-fighting gun head 4 to facilitate flexible and quick operation by firefighters.

[0050] Specifically, the command input module 7 is fixed to the outer surface of the fire gun head 4 by bonding.

[0051] In one embodiment, the command input module 7 includes a first push rod for adjusting the flow rate of the fire-fighting liquid supply system and a second push rod for adjusting the spray speed. Pushing the first or second push rod forward increases the flow rate or spray speed of the fire-fighting liquid supply system, while pushing the first or second push rod backward decreases the flow rate or spray speed of the fire-fighting liquid supply system. The sliding portions of the first and second push rods are built with linear potentiometers or Hall effect sensors that convert physical displacement into electrical signals. The potentiometer or Hall effect sensor signal lines are connected to the input ports of the controller 6.

[0052] In another embodiment, the command input module 7 is a button panel having four buttons: forward, backward, left, and right. These buttons respectively increase the fire-fighting liquid supply system's spray flow rate, decrease the fire-fighting liquid supply system's spray flow rate, increase the fire-fighting liquid supply system's spray speed, and decrease the fire-fighting liquid supply system's spray speed. Each button corresponds to a set of normally open contacts connected to a digital input port of the controller 6 via a shielded cable.

[0053] Preferably, the valve 5 is an electric regulating valve.

[0054] Furthermore, the valve plate of valve 5 acts on the water outlet of fire lance head 4 that connects to the outside atmosphere. When the valve opening is increased, the flow area of the liquid sprayed to the outside by fire lance head 4 is increased, thereby increasing the actual area of the water outlet of fire lance head 4 that connects to the outside atmosphere. Controller 6 reads the firefighter's instructions from instruction input module 7 and controls the adjustable speed motor 2 and valve 5.

[0055] Preferably, the fire pump 1 is a centrifugal pump.

[0056] The control method of the fire-fighting fluid supply system comprises the following steps:

[0057] The controller 6 reads the firefighter's command from the command input module 7 once every preset time interval Δt, performs a control operation and records the control operation;

[0058] Let t=0 be the start-up time of the fire-fighting liquid supply system. Then, at time t=iΔt, based on the instruction at that time, the valve opening, the speed of the adjustable-speed motor 2, and the control operation record since the start-up, the control operation is executed according to the following specified rules;

[0059] i. When the instruction at this moment is to increase the spray flow rate:

[0060] If the valve opening K at this moment i <Valve opening maximum threshold K max , and the number of valve opening increase control operations performed from t=(ia)Δt to t=(i-1)Δt is not a times, then the valve opening is increased by ΔK;

[0061] If the valve opening K at this moment i = Maximum valve opening threshold K max , or the number of valve opening increase control operations performed from t=(ia)Δt to t=(i-1)Δt is a times, then the speed of the adjustable speed motor 2 is increased by Δn;

[0062] ii. When the instruction at this moment is to increase the spray speed:

[0063] If the valve opening K at this moment i > Minimum valve opening threshold K min , and the number of valve opening reduction control operations performed from t=(ib)Δt to t=(i-1)Δt is not b times, then the valve opening is reduced by ΔK;

[0064] If the valve opening K at this moment i = minimum valve opening threshold K min , or the number of valve opening reduction control operations executed from time t=(ib)Δt to time t=(i-1)Δt is b times, then the speed of the adjustable speed motor 2 is increased by Δn;

[0065] iii. When the instruction at this moment is to reduce the spray flow rate:

[0066] If the speed of motor 2 can be adjusted at this moment, n i >Minimum speed threshold n for adjustable speed motor 2 min , and the number of speed reduction control operations of the adjustable-speed motor 2 executed from time t=(ic)Δt to time t=(i-1)Δt is not c times, then the speed of the adjustable-speed motor 2 is reduced by Δn;

[0067] If the speed of motor 2 can be adjusted at this moment, n i = Minimum speed threshold of adjustable speed motor 2 n min , or the number of speed control operations for reducing the speed of the adjustable speed motor 2 executed from time t=(ic)Δt to time t=(i-1)Δt is c times, then the valve opening is reduced by ΔK;

[0068] iv. When the instruction at this moment is to reduce the spray speed:

[0069] If the speed of motor 2 can be adjusted at this moment, n i >Minimum speed threshold n for adjustable speed motor 2 min , and the number of speed reduction control operations of the adjustable-speed motor 2 executed from time t=(id)Δt to time t=(i-1)Δt is not d times, then the speed of the adjustable-speed motor 2 is reduced by Δn;

[0070] If the speed of motor 2 can be adjusted at this moment, n i = Minimum speed threshold of adjustable speed motor 2 n min , or the number of speed control operations of reducing the speed of the adjustable speed motor 2 executed from time t=(id)Δt to time t=(i-1)Δt is d times, then the valve opening is increased by ΔK;

[0071] The above i, a, b, c, and d are all positive integers, Δn is the motor speed change in a single motor speed control operation, and ΔK is the valve opening change in a single valve opening control operation.

[0072] To account for special circumstances, according to the above rules, if the calculated value at a certain moment is negative, that moment is corrected to t = 0. If the difference between i and any of the four parameters a, b, c, and d is less than zero, the difference is corrected to zero. In other words, according to the calculation rules above, considering that the value of i may be small and the values of a, b, c, and d may be large during the initial system startup, special provisions are made: if ia < 0, set ia = 0; if ib < 0, set ib = 0; if ic < 0, set ic = 0; and if id < 0, set id = 0.

[0073] Preferably, if according to the above specified rules, the speed of the adjustable speed motor 2 after a speed control operation is greater than the maximum speed threshold n of the adjustable speed motor 2 max Or less than the minimum speed threshold n of the adjustable speed motor 2 min , then the actual speed control operation of the adjustable speed motor 2 is to the maximum speed threshold value n of the adjustable speed motor 2 max Or the minimum speed threshold n of the adjustable speed motor 2 min ;

[0074] If according to the above specified rules, the opening degree after a certain valve opening control operation is greater than the maximum valve opening threshold K max Or less than the minimum valve opening threshold K min , then the valve opening is actually controlled to the maximum valve opening threshold K max Or the minimum threshold value of valve opening K min .

[0075] In this way, the speed of the adjustable-speed motor 2 and the valve opening are always controlled between their respective minimum and maximum thresholds.

[0076] Preferably, at the same time, the controller 6 only receives one of the two instructions of adjusting the spray flow rate of the fire-fighting liquid supply system and adjusting the spray speed of the fire-fighting liquid supply system; if the firefighter inputs both instructions of adjusting the spray flow rate of the fire-fighting liquid supply system and adjusting the spray speed of the fire-fighting liquid supply system at the same time, the instruction will be decomposed into two instructions, and the instruction of the same type as the previous instruction will be executed first, and then the instruction of a different type from the previous instruction will be executed.

[0077] In one embodiment, at a certain moment, a firefighter simultaneously inputs two different types of instructions, one for adjusting the liquid flow rate of the fire-fighting liquid supply system and the other for adjusting the liquid speed of the fire-fighting liquid supply system. However, the instruction executed at the previous moment was for adjusting the liquid flow rate of the fire-fighting liquid supply system. Therefore, for the above two different types of instructions input at this moment, the instruction of the same type as that at the previous moment, which is for adjusting the liquid flow rate of the fire-fighting liquid supply system, is executed first, and then the instruction of the different type as that at the previous moment, which is for adjusting the liquid speed of the fire-fighting liquid supply system, is executed.

[0078] The present invention also discloses a storage medium, which is a computer-readable storage medium. The storage medium stores a control program of a fire protection fluid supply system control method. When the control program of the fire protection fluid supply system control method is executed by a processor, the steps of the fire protection fluid supply system control method are implemented.

[0079] like Figure 1-2 As shown, the rules used in executing the control operation in the control method of the present invention are further introduced in combination with the fire protection fluid supply system adjustment principle diagram.

[0080] Figure 2In the figure, the horizontal axis represents flow rate, and the vertical axis represents head or total resistance of the piping system. H1 to H5 represent the performance curves of fire pump 1 at five different speeds, with the speed increasing from H1 to H5. F1 to F5 represent the resistance curves of the liquid supply system piping at five different valve openings, with the total resistance increasing from F1 to F5.

[0081] At a certain moment, fire pump 1 works at the intersection point P of curve H3 and curve F3. 3,3 :

[0082] 1. When the command to increase the spray flow rate is continuously input, the valve opening is increased first, which reduces the pipeline resistance. After executing the control operation of increasing the valve opening by ΔK several times, the pipeline resistance curve changes from curve F3 to curve F2. The intersection of curve H3 and curve F2 is P 3,2 , the spray flow rate increases. At this time, if the valve opening is further increased, even if the valve opening does not reach its maximum threshold value K max , although the pipeline resistance curve can be changed from curve F2 to curve F1, the intersection of curve H3 and curve F1 is P 3,1 , the spray flow rate can continue to increase; however, due to the continuous and repeated control operations to increase the valve opening, the flow area of the fire gun head 4 to the external spray liquid increases too quickly, so it also brings about a rapid reduction in the spray speed.

[0083] Therefore, when the pipeline resistance curve changes continuously from curve F3 to curve F2, the valve opening is no longer increased, and the speed of the adjustable speed motor 2 is increased by Δn, so that the flow-head curve of the fire pump 1 changes from curve H3 to curve H4. The intersection of curve H4 and curve F2 is P 4,2 The liquid spraying flow rate also increases, but the flow area of the fire gun head 4 spraying liquid to the outside remains unchanged, which helps to compensate for the loss of liquid spraying speed caused by the continuous increase in the valve opening.

[0084] 2. When the command to increase the injection speed is continuously input, the strategy of reducing the valve opening is first adopted, which quickly increases the injection speed. After executing the control operation of reducing the valve opening by ΔK several times, the pipeline resistance curve changes from curve F3 to curve F4, and the intersection of curve H3 and curve F4 is P 3,4 , while increasing the injection speed, the injection flow rate is also reduced. At this time, if the valve opening is further reduced, the pipeline resistance curve changes from curve F4 to curve F5, and the intersection of curve H3 and curve F5 is P 3,5 , the spray flow rate will be reduced to a lower level.

[0085] Therefore, when the pipeline resistance curve changes continuously from curve F3 to curve F4, the valve opening is no longer reduced, and the speed of the adjustable speed motor 2 is increased by Δn, so that the flow-head curve of the fire pump 1 changes from curve H3 to curve H4. The intersection of curve H4 and curve F4 is P 4,4 The liquid spray flow rate increases, but the flow area of the fire gun head 4 spraying liquid to the outside remains unchanged, so the liquid spray speed also increases, which helps to compensate for the liquid spray flow loss caused by continuously reducing the valve opening.

[0086] 3. When the command to reduce the spray flow rate is continuously input, the strategy of reducing the adjustable motor speed is first adopted. After executing the control operation of reducing the adjustable motor speed by Δn several times, the performance curve of the fire pump 1 changes from curve H3 to curve H2. The intersection of curve H2 and curve F3 is P 2,3 , the spray flow rate decreases. At this time, if the adjustable motor speed is further reduced, the performance curve of the fire pump 1 can be changed from curve H2 to curve H1. The intersection of curve H1 and curve F3 is P 1,3 , the spray flow rate continues to decrease; but due to the above adjustment process, the flow area of the fire gun head 4 to the outside spray has remained unchanged, which will cause the spray speed to continue to decrease rapidly.

[0087] Therefore, when the performance curve of fire pump 1 changes from curve H3 to curve H2, the motor speed is no longer adjusted low, and the valve opening is reduced by ΔK. The pipeline resistance curve changes from curve F3 to curve F4. The intersection of curve H2 and curve F4 is P 2,4 The liquid spray flow rate is reduced, but the flow area of the fire gun head 4 spraying liquid to the outside is reduced faster, so the liquid spray speed is increased, which helps to compensate for the liquid spray speed loss caused by reducing the speed of the adjustable motor.

[0088] 4. When the command to reduce the spray speed is continuously input, the strategy of reducing the adjustable motor speed is first adopted. After executing the control operation of reducing the adjustable motor speed by Δn several times, the performance curve of the fire pump 1 changes from curve H3 to curve H2. The intersection of curve H2 and curve F3 is P 2,3 , the spray flow rate decreases, and the spray speed also decreases accordingly. At this time, if the adjustable motor speed is further reduced, the performance curve of the fire pump 1 can be changed from curve H2 to curve H1. The intersection of curve H1 and curve F3 is P 1,3 , the spray velocity continues to decrease, but this will also cause the spray flow rate to continue to decrease rapidly.

[0089] Therefore, when the performance curve of fire pump 1 changes from curve H3 to curve H2, the motor speed is no longer adjusted low, and the valve opening is increased by ΔK. The pipeline resistance curve changes from curve F3 to curve F2. The intersection of curve H2 and curve F2 is P 2,2The spray flow rate increases, but the flow area of the fire gun head 4 spraying liquid to the outside increases faster, so the spray speed can be reduced, which helps to compensate for the spray flow loss caused by reducing the adjustable motor speed.

[0090] It is necessary to combine the knowledge of centrifugal pumps and fluid mechanics to understand the technical principles of this solution.

[0091] First, the basic theoretical knowledge related to this program is introduced.

[0092] In terms of spray flow regulation, the operating flow of the liquid supply system is the intersection of the centrifugal pump performance curve and the pipeline resistance curve. A Cartesian coordinate system is established with flow as the horizontal axis and head / resistance as the vertical axis to introduce the characteristics of the two: the general rule of the flow-head curve of a centrifugal pump is that as the flow increases, the head continues to decrease; the rule of the pipeline resistance curve is that as the flow increases, the resistance continues to increase. The total pipeline resistance of the fire-fighting liquid supply system mainly comes from two parts: the longitudinal resistance of the liquid supply pipe 3 and the local resistance of the valve 5 at the fire-fighting gun head 4. When the speed of the centrifugal pump increases, its output increases, and the flow-head curve of the centrifugal pump moves to the upper right of the coordinate system as a whole; when the valve opening on the pipeline becomes smaller, the pipeline resistance increases, and the pipeline resistance curve becomes steeper.

[0093] Since volumetric flow rate is the product of flow area and flow velocity, if the flow rate through the liquid supply system remains roughly constant, reducing the valve opening on the fire lance head 4 will reduce the flow area through which the fire lance head 4 sprays liquid to the outside, resulting in an increase in the liquid spray velocity and a longer spray distance at the same spray angle. However, if the valve opening on the fire lance head 4 is reduced too much, the resistance of the liquid supply system will increase.

[0094] Generally speaking, for centrifugal pumps, an increase in flow rate means an increase in shaft power and higher energy consumption of the equipment; an increase in speed and output is often accompanied by an increase in energy consumption and increased wear and vibration, which leads to a reduction in service life.

[0095] Then, the control operation rules are explained in detail. The controller 6 performs instruction reading, judgment and control operations once every time interval of Δt.

[0096] 1. When the instruction at a certain moment is to increase the spray flow rate, the strategy of giving priority to increasing the valve opening is adopted: this quickly reduces the total resistance of the liquid supply system, makes the pipeline resistance curve flatter, and the intersection of the pipeline resistance curve and the centrifugal pump performance curve moves toward the direction of large flow rate. While increasing the spray flow rate, it is beneficial to reduce resistance loss, improve energy efficiency, and prevent the reduction of the centrifugal pump's service life due to increasing the speed.

[0097] However, when either of the two special situations occurs, the strategy of increasing the valve opening is not adopted, but instead the strategy of increasing the adjustable motor speed is adopted: this causes the flow-head curve of the centrifugal pump to move as a whole to the upper right of the coordinate system, and the intersection of the pipeline resistance curve and the centrifugal pump performance curve also moves toward the direction of large flow, thereby also achieving the purpose of increasing the injection flow rate, although this is likely to mean an increase in energy consumption and a reduction in the service life of the centrifugal pump.

[0098] The first of the two special cases mentioned above is that the valve opening has reached the maximum threshold at this moment, so there is no room for further increase. If the spray flow rate needs to be increased at this time, it can only be achieved by increasing the speed of the adjustable motor. The second of the two special cases mentioned above is that in the history before the current moment, the control operation of increasing the valve opening has been taken a number of times in a row. Although this has increased the spray flow rate to a certain extent, it will cause the flow area of the fire gun head 4 spraying liquid to the outside to increase too quickly, resulting in a too-rapid decrease in the spray speed. In common application scenarios, users do not want to increase the spray flow rate at the expense of the spray speed. Therefore, when the second special case occurs, the control operation of increasing the adjustable motor speed is performed once to increase the spray flow rate. This operation increases the spray speed while increasing the spray flow rate, which helps to compensate for the loss of spray speed caused by the continuous increase in the valve opening, thereby being more in line with the intended use and making the system run more stably.

[0099] 2. When the instruction at a certain moment is to increase the spray speed, the strategy of prioritizing reducing the valve opening is adopted: this not only immediately reduces the flow area of the fire lance head 4 spraying liquid to the outside, helping to quickly increase the spray speed, but also does not cause an increase in energy consumption or a reduction in the service life of the centrifugal pump. However, when either of the two special situations occurs, the strategy of reducing the valve opening is not adopted, and instead the strategy of increasing the adjustable motor speed is adopted: this causes the centrifugal pump's flow-head curve to move toward the upper right of the coordinate system as a whole, and the intersection of the pipeline resistance curve and the centrifugal pump performance curve moves toward the direction of high flow, resulting in an increase in the spray flow rate. At the same valve opening, an increase in the spray flow rate also means an increase in the spray speed.

[0100] The first of the two special cases mentioned above is that the valve opening has reached the minimum threshold at this moment, so there is no room for further reduction. If the spray flow rate needs to be increased at this time, it can only be achieved by increasing the adjustable motor speed. The second of the two special cases mentioned above is that in the history before the current moment, the control operation of reducing the valve opening has been carried out b times in a row. Although this has increased the spray flow rate to a certain extent, it will cause the flow area of the fire lance head 4 spraying liquid to the outside to decrease too quickly, resulting in an excessive increase in pipeline resistance. The pipeline resistance curve quickly becomes too steep, and the intersection of the pipeline resistance curve and the centrifugal pump performance curve moves rapidly toward the direction of low flow, causing an excessive decrease in the spray flow rate. In typical application scenarios, users do not want to increase the spray flow rate at the expense of excessively sacrificing the spray flow rate. Therefore, when the second special case occurs, a single control operation of increasing the adjustable motor speed is performed to increase the spray flow rate. This operation simultaneously increases the spray flow rate and the spray speed, helping to compensate for the spray flow loss caused by the previous continuous reduction of the valve opening, thereby better meeting the user's intended use and making the system more stable.

[0101] 3. When the instruction at a certain moment is to reduce the spray flow rate, the strategy of prioritizing the reduction of the adjustable motor speed is adopted: this causes the centrifugal pump's flow-head curve to move toward the lower left of the coordinate system as a whole, and the intersection of the pipeline resistance curve and the centrifugal pump performance curve moves toward the direction of low flow, resulting in a reduction in the spray flow rate. This helps to reduce motor energy consumption and vibration wear. However, when either of the two special situations occurs, the strategy of reducing the adjustable motor speed is not adopted, and instead the strategy of reducing the valve opening is adopted: this leads to an increase in pipeline resistance, the pipeline resistance curve quickly becomes steeper, and the intersection of the pipeline resistance curve and the centrifugal pump performance curve moves toward the direction of low flow, resulting in a decrease in the spray flow rate.

[0102] The first of the two special cases mentioned above is that the adjustable motor speed has reached the minimum threshold at this moment, so there is no room for further reduction. If the spray flow rate needs to be reduced at this time, it can only be achieved by reducing the valve opening. The second of the two special cases mentioned above is that in the history before the current moment, the control operation of reducing the adjustable motor speed has been taken c times in a row. While reducing the flow rate, because the valve opening has not changed, the spray speed also drops too quickly. In common application scenarios, users do not want to reduce the spray flow rate at the expense of excessively sacrificing the spray speed. Therefore, when the second special case occurs, a single control operation of reducing the valve opening is performed to reduce the flow rate. This operation, while reducing the spray flow rate, actually increases the spray speed by significantly reducing the flow area of the fire gun head 4 spraying liquid to the outside. This helps to compensate for the spray speed loss caused by the previous continuous reduction of the adjustable motor speed, thereby better meeting the user's intention and making the system run more stably.

[0103] 4. When the instruction at a certain moment is to reduce the spray speed, the strategy of prioritizing reducing the adjustable motor speed is adopted: this causes the centrifugal pump's flow-head curve to move toward the lower left of the coordinate system as a whole, and the intersection of the pipeline resistance curve and the centrifugal pump performance curve moves toward the direction of low flow, resulting in a decrease in the spray flow rate. However, because the valve opening does not change, the flow area of the fire lance head 4 spraying liquid to the outside remains unchanged, resulting in a corresponding decrease in the spray speed. This helps reduce motor energy consumption and vibration wear. However, when either of the two special situations occurs, the strategy of reducing the adjustable motor speed is not adopted, and the strategy of increasing the valve opening is adopted instead: this increases the flow area of the fire lance head 4 spraying liquid to the outside, resulting in a decrease in the spray speed when the change in the spray flow rate is not large.

[0104] The first of the two special cases mentioned above is that the adjustable motor speed has already reached the minimum threshold, leaving no room for further reduction. If the spray flow rate needs to be reduced at this point, it can only be achieved by increasing the valve opening. The second of the two special cases is that, prior to the current moment, control operations to reduce the adjustable motor speed have been executed d times in succession. This, while reducing the spray flow rate, also results in an excessively rapid decrease in the spray flow rate. In typical applications, users do not want to sacrifice excessive spray flow rate to reduce the spray speed. Therefore, when the second special case occurs, a single control operation to increase the valve opening is performed to reduce the spray speed. This operation, while reducing the spray speed, also reduces the pipeline resistance by increasing the flow area through which the fire lance head 4 sprays liquid externally, making the pipeline resistance curve flatter. The intersection of the pipeline resistance curve and the centrifugal pump performance curve shifts toward the direction of high flow, resulting in an increase in the spray flow rate. This helps compensate for the spray flow rate loss caused by the previous continuous reduction of the adjustable motor speed, thereby better meeting the user's intended use and ensuring more stable system operation.

[0105] The present invention will be further described below with reference to the accompanying drawings and examples.

[0106] Example:

[0107] Please refer to Figure 1 、 2 Understand this embodiment.

[0108] In this embodiment, the fire pump 1 is a centrifugal pump, the liquid medium is clean water, a=b=c=d=4, and the maximum speed threshold of the adjustable speed motor 2 is n max =3000r / min, the minimum speed threshold of adjustable motor 2 n min =1000r / min, the maximum threshold value of valve opening K max =100%, minimum valve opening threshold K min=5%, the motor speed change of a single motor speed control operation Δn=100r / min, the valve opening change of a single valve opening control operation ΔK =5%, and the time interval Δt =10s.

[0109] After the liquid supply system is turned on, it is in the default initial state, the speed of the adjustable speed motor 2 is 2000r / min, and the valve opening is 70%.

[0110] Let t=0 be the startup time of the fire-fighting liquid supply system, and i=1 to i=10 correspond to the time period from t=10s to t=100s, during which no command input is received.

[0111] Between i=11 and i=17, corresponding to the time period from t=110s to t=170s, the command input to increase the spray flow rate is continuously received and the control operation is executed according to the rule:

[0112] When i=11, i.e. t=110s, the valve opening , ,and to If the number of valve opening control operations executed at the moment is 0 and not a=4, the valve opening is increased by ΔK=5%;

[0113] When i=12, i.e. t=120s, the valve opening K 12 =75%, K 12 <K max , and the number of valve opening increase control operations performed from t=80s to t=110s is 1, not 4, then the valve opening is increased by 5%;

[0114] When i=13, i.e. t=130s, the valve opening K 13 =80%, K 13 <K max , and the number of valve opening increase control operations performed from t=90s to t=120s is 2, not 4, then the valve opening is increased by 5%;

[0115] When i=14, i.e. t=140s, the valve opening K 14 =85%, K 14 <K max , and the number of valve opening increase control operations performed from t=100s to t=130s is 3, not 4, then the valve opening is increased by 5%;

[0116] When i=15, i.e. t=150s, the valve opening K 15 =90%, K 15 <K max, and the number of valve opening increase control operations performed from t=110s to t=140s is a=4 times, then the speed of the adjustable speed motor 2 is increased by Δn=100r / min;

[0117] When i=16, i.e. t=160s, the valve opening K 16 =95%, K 16 <K max , and the number of valve opening increase control operations performed from t=120s to t=150s is 3, not 4, then the valve opening is increased by 5%;

[0118] When i=17, i.e. t=170s, the valve opening K 17 =100%=K max , then increase the speed of the adjustable speed motor 2 by Δn=100r / min.

[0119] It should be noted that in order to achieve a better technical effect, the appropriate values of a, b, c, d, as well as Δn and ΔK, should be determined through modeling and simulation or multiple tests based on the performance curve of the fire pump 1, the pipeline resistance curve, and the characteristics of the flow area and resistance changes caused by changes in valve opening. For example, when the control measure of reducing the valve opening is adopted instead of continuously inputting a command to reduce the spray flow rate, the spray flow rate will decrease due to the increase in pipeline resistance. However, at the same time, it is necessary to ensure that the flow area of the fire lance head 4 spraying liquid to the outside decreases relatively faster. Only in this way can the spray speed be increased, thereby compensating for the loss of spray speed caused by reducing the adjustable motor speed.

[0120] Therefore, the technical solution in this embodiment can comprehensively consider factors such as the operating energy consumption and operating life loss of the liquid supply system after the liquid supply system receives the firefighter's on-site spray flow and spray speed adjustment instructions, and pay full attention to minimizing the significant impact of one working state on another working state in a short period of time when adjusting the working state, avoiding drastic fluctuations in the output. At the same time, the adjustment method is more flexible, fast, efficient and safe, and can be achieved through simple modification on the basis of the design of the existing fire liquid supply system mainly composed of a fire pump 1 and a fire gun head 4.

[0121] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiment. All technical solutions based on the concept of the present invention are within the scope of protection of the present invention. It should be noted that for those skilled in the art, various improvements and modifications that do not depart from the principles of the present invention should also be considered as within the scope of protection of the present invention.

Claims

1. A control method for a fire-fighting fluid supply system, characterized in that: Applicable to a fire-fighting fluid supply system, the fire-fighting fluid supply system comprising: A fire pump (1), wherein the fire pump (1) is provided with an adjustable speed motor (2), and the adjustable speed motor (2) is used to drive the impeller of the fire pump (1) to rotate; Fire lance head (4); A liquid supply pipe (3), the liquid supply pipe (3) being connected between the fire-fighting gun head (4) and the outlet of the fire-fighting pump (1); A valve (5), the valve (5) being mounted on the fire-fighting gun head (4) and being used to adjust the flow area of the fire-fighting gun head (4) spraying liquid to the outside; An instruction input module (7), the instruction input module (7) being used to receive an adjustment instruction for a liquid spray flow rate and / or a liquid spray speed; A controller (6), the controller (6) being electrically connected to the adjustable speed motor (2), the valve (5), and the instruction input module (7), respectively, and the controller (6) being used to control the speed of the adjustable speed motor (2) and the opening of the valve (5) according to instructions on the instruction input module (7); The control method comprises the following steps: The controller (6) reads the firefighter's instruction from the instruction input module (7) once every preset time interval Δt, performs a control operation, and records the control operation; Let t = 0 be the time when the fire-fighting liquid supply system is turned on. Then, at time t = iΔt, the control operation is executed according to the specified rules based on the instruction at that time, the valve opening, the speed of the adjustable speed motor (2), and the control operation record since the start-up. The specified rules include rules corresponding to when the instruction at the moment is to increase the liquid injection flow rate, when the instruction at the moment is to increase the liquid injection speed, when the instruction at the moment is to reduce the liquid injection flow rate, and when the instruction at the moment is to reduce the liquid injection speed; i. When the instruction at this moment is to increase the spray flow rate: If the valve opening K at this moment i <Valve opening maximum threshold K max , and the number of valve opening increase control operations performed from t=(ia)Δt to t=(i-1)Δt is not a times, then the valve opening is increased by ΔK; If the valve opening K at this moment i = Maximum valve opening threshold K max , or the number of valve opening control operations performed from time t=(ia)Δt to time t=(i-1)Δt is a, then the speed of the adjustable speed motor (2) is increased by Δn; ii. When the instruction at this moment is to increase the spray speed: If the valve opening K at this moment i > Minimum valve opening threshold K min , and the number of valve opening reduction control operations performed from t=(ib)Δt to t=(i-1)Δt is not b times, then the valve opening is reduced by ΔK; If the valve opening K at this moment i = minimum valve opening threshold K min , or the number of valve opening reduction control operations executed from time t=(ib)Δt to time t=(i-1)Δt is b times, then the speed of the adjustable speed motor (2) is increased by Δn; iii. When the instruction at this moment is to reduce the spray flow rate: If the speed of the adjustable motor (2) at this moment is n i >Minimum speed threshold value n for adjustable speed motor (2) min , and the number of speed control operations for reducing the speed of the adjustable speed motor (2) executed from time t=(ic)Δt to time t=(i-1)Δt is not c times, then the speed of the adjustable speed motor (2) is reduced by Δn; If the speed of the adjustable motor (2) at this moment is n i = Minimum speed threshold of adjustable speed motor (2) n min , or the number of speed control operations of reducing the speed of the adjustable speed motor (2) executed from time t=(ic)Δt to time t=(i-1)Δt is c times, then the valve opening is reduced by ΔK; iv. When the instruction at this moment is to reduce the spray speed: If the speed of the adjustable motor (2) at this moment is n i >Minimum speed threshold value n for adjustable speed motor (2) min , and the number of speed control operations for reducing the speed of the adjustable speed motor (2) executed from time t=(id)Δt to time t=(i-1)Δt is not d times, then the speed of the adjustable speed motor (2) is reduced by Δn; If the speed of the adjustable motor (2) at this moment is n i = Minimum speed threshold of adjustable speed motor (2) n min , or the number of speed control operations of reducing the speed of the adjustable speed motor (2) executed from time t=(id)Δt to time t=(i-1)Δt is d times, then the valve opening is increased by ΔK; The above i, a, b, c, and d are all positive integers, Δn is the motor speed change in a single motor speed control operation, and ΔK is the valve opening change in a single valve opening control operation.

2. A method for controlling a fire-fighting fluid supply system according to claim 1, characterized in that: The command input module (7) is arranged on the fire-fighting gun head (4).

3. The control method of a fire-fighting fluid supply system according to claim 1, characterized in that: The valve (5) is an electric regulating valve.

4. The control method of a fire-fighting liquid supply system according to claim 1, characterized in that: The fire pump (1) is a centrifugal pump.

5. The control method of a fire-fighting fluid supply system according to claim 1, characterized in that: If, according to the specified rule, the speed of the adjustable speed motor (2) after a speed control operation is greater than the maximum speed threshold value n of the adjustable speed motor (2), max Or less than the minimum speed threshold n of the adjustable speed motor (2) min , then the speed of the adjustable speed motor (2) is actually controlled to the maximum speed threshold value n of the adjustable speed motor (2) max Or the minimum speed threshold value n of the adjustable speed motor (2) min ; If, according to the specified rules, the valve opening after a certain valve opening control operation is greater than the maximum valve opening threshold K max Or less than the minimum valve opening threshold K min , then the valve opening is actually controlled to the maximum valve opening threshold K max Or the minimum threshold value of valve opening K min .

6. The control method of a fire-fighting fluid supply system according to claim 1, characterized in that: At the same time, the controller (6) receives only one of the two instructions, one for adjusting the spray flow rate of the fire-fighting liquid supply system and the other for adjusting the spray speed of the fire-fighting liquid supply system; If the firefighter inputs two instructions at the same time, namely, adjusting the spray flow rate of the fire-fighting fluid supply system and adjusting the spray speed of the fire-fighting fluid supply system, the instruction will be decomposed into two instructions. The instruction of the same type as the previous instruction will be executed first, and then the instruction of a different type from the previous instruction will be executed.

7. A storage medium, wherein the storage medium is a computer-readable storage medium, characterized in that: The storage medium stores a control program of a fire-fighting fluid supply system control method, wherein when the control program of the fire-fighting fluid supply system control method is executed by a processor, the steps of the fire-fighting fluid supply system control method as described in any one of claims 1 to 6 are implemented.

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