A water pump control method without a flow sensor

Abstract

The present invention relates to the technical field of water pump control, and specifically to a water pump control method without a flow sensor, which includes the following steps: collecting the real-time pressure P through a pressure sensor and collecting the real-time temperature T through a temperature sensor; water shortage detection; static pressure monitoring; motor control; judging whether the motor operation flag is set. If the motor operation flag is set, the motor is started; otherwise, the motor is stopped. By determining the real-time pressure value and temperature change situation, the start and stop of the water pump can be controlled. Compared with controlling the start and stop of the water pump by using a flow sensor, the pressure sensor and temperature sensor are not easily damaged, reducing the repair rate and lowering the use cost of the water pump. At the same time, by using the pressure sensor and temperature sensor in cooperation, it is possible to achieve a warning of water shortage in the pipe network and detect the static pressure of the pipe network. When water comes, the water pump can start automatically, reducing the need for manual intervention.

Description

Technical Field

[0001] The present invention relates to the technical field of water pump control, and in particular to a flow sensor-free water pump control method. Background Art

[0002] Water pumps are an important part of water supply and drainage systems. With the development of science and technology, intelligent control systems are being used more and more widely in the field of civil water pumps. At present, the more common application is the use of pressure switch sensors and flow switch sensors. The pressure switch sensor detects the pressure signal of the water pump and outputs the pressure switch signal to the water pump controller. The flow switch sensor detects the water flow signal of the water pump and outputs the water flow switch signal to the water pump controller. The water pump controller controls the start and stop of the water pump through the received pressure switch signal and water flow switch signal, thereby realizing intelligent water supply.

[0003] However, the cost of flow sensors is high, and the failure rate of flow sensors is high, and they are prone to jamming and causing erroneous flow signals.

[0004] Based on this, the present invention designs a water pump control method without flow sensor to solve the above technical problems. Summary of the Invention

[0005] The object of the present invention is to provide a flow sensorless water pump control method and a method of using the same to solve the above technical problems.

[0006] To achieve the above object, the present invention provides the following technical solution: a flow sensorless water pump control method, comprising the following steps:

[0007] S1. Initialize the system, set the forced running time, and set the motor running flag;

[0008] S2, collect real-time pressure P through the pressure sensor, and collect real-time temperature T through the temperature sensor;

[0009] S3, water shortage detection;

[0010] S4, static pressure monitoring;

[0011] S5, motor control;

[0012] S6. Determine whether the motor running flag is set. If the motor running flag is set, start the motor; otherwise, stop the motor.

[0013] Preferably, in step S3, the method for water shortage detection is as follows:

[0014] Determine whether the water pump is running; if the water pump is in the running state, determine whether the real-time pressure P is less than the water shortage pressure Pw, and the duration is greater than or equal to the set time Tw;

[0015] If the real-time pressure P is less than the water shortage pressure Pw, and the duration is greater than or equal to the set time Tw, set the water shortage fault;

[0016] Otherwise, determine whether the real-time pressure P is less than the system minimum pressure Pi;

[0017] If the real-time pressure P is less than the system minimum pressure Pi, then determine whether the difference between the real-time temperature T and the starting temperature Tb is greater than the threshold value Tx. If the difference between the real-time temperature T and the starting temperature Tb is greater than the threshold value Tx, set the water shortage fault.

[0018] Preferably, in the step S4, the method for static pressure monitoring is as follows:

[0019] Determine whether the water pump is running;

[0020] If the water pump is in the stopped state, determine whether the static pressure rising flag is set. If the static pressure rising flag is not set, determine whether the stable pressure cache value Ph is 0;

[0021] If the stable pressure cache value Ph is 0, determine whether the real-time pressure P has been stable for the set duration Th. If the real-time pressure P is stable within the set time Th, save the stable pressure cache value Ph equal to the real-time pressure P;

[0022] If the stable pressure cache value Ph is not 0, determine whether the difference between the real-time pressure P and the stable pressure cache value Ph is greater than the threshold value Phx. If the difference between the real-time pressure P and the stable pressure cache value Ph is greater than the threshold value Phx, set the static pressure rising flag.

[0023] Preferably, in the step S5, the method for motor control is as follows:

[0024] Determine whether the water pump is running;

[0025] If the water pump is running, determine whether the water pump is in forced operation;

[0026] If the water pump is not in forced operation, then determine whether the real-time pressure P is greater than the difference between the shutdown pressure Pt minus the threshold value Ptx;

[0027] If so, set the cached pressure Pb equal to the real-time pressure P, set the shutdown pressure Pt equal to the cached pressure Pb, set the starting pressure Pq equal to the shutdown pressure Pt multiplied by the set percentage value Qx, set the shutdown pressure curve detection, clear the static pressure rising flag, and then, clear the motor running flag bit;

[0028] If not, determine whether the difference between the real-time temperature T and the starting temperature Tb is greater than the threshold value Tx;

[0029] If so, set the buffer pressure Pb equal to the real-time pressure P, set the shutdown pressure Pt equal to the buffer pressure Pb, set the starting pressure Pq equal to the shutdown pressure Pt multiplied by the set percentage value Qx, set the shutdown pressure curve detection, clear the static pressure rise flag, and then, clear the motor running flag bit;

[0030] If the water pump is shut down, determine whether the static pressure rise flag is set;

[0031] If so, set the starting temperature Tb equal to the real-time temperature T, and then, set the motor running flag bit;

[0032] If the static pressure rise flag is not set, determine whether the water shortage fault is set;

[0033] If so, determine whether the water inflow detection is triggered. If so, set the starting temperature Tb equal to the real-time temperature T, and then, set the motor running flag bit;

[0034] If the water shortage fault is not set, determine whether the shutdown pressure curve detection is set;

[0035] If the shutdown pressure curve detection is set, perform the shutdown pressure curve detection, and determine whether the real-time pressure P drop rate Pd is greater than the threshold value Pdx;

[0036] If the real-time pressure P drop rate Pd is greater than the threshold value Pdx, correct the shutdown pressure so that the shutdown pressure Pt is equal to the buffer pressure Pb plus the threshold value Ptb, set the starting temperature Tb equal to the real-time temperature T, and then, set the motor running flag bit;

[0037] If the real-time pressure P drop rate Pd is not greater than the threshold value Pdx, determine whether rust removal is triggered;

[0038] If the shutdown pressure curve detection is not set, determine whether rust removal is triggered;

[0039] If rust removal is triggered, set the starting temperature Tb equal to the real-time temperature T, and then, set the motor running flag bit;

[0040] If rust removal is not triggered, determine whether anti-freezing is triggered;

[0041] If so, set the starting temperature Tb equal to the real-time temperature T, and then, set the motor running flag bit;

[0042] If anti-freezing is not triggered, determine whether the real-time pressure P triggers the starting pressure Pq;

[0043] If so, set the starting temperature Tb equal to the real-time temperature T, and then, set the motor running flag bit.

[0044] Compared with the prior art, the beneficial effects of the present invention are as follows: The real-time pressure value of the water pump during operation is detected by a pressure sensor, and the real-time temperature during the operation of the water pump is detected by a temperature sensor. By judging the real-time pressure value and the temperature change, the start and stop of the water pump can be controlled. Compared with using a flow sensor to control the start and stop of the water pump, the usage cost of the water pump is reduced. Moreover, the pressure sensor and the temperature sensor are not easily damaged, reducing the repair rate. At the same time, by using the pressure sensor and the temperature sensor in cooperation, it is possible to achieve warning of water shortage in the pipe network and detection of the static pressure in the pipe network. When water comes, the water pump can start automatically, reducing the participation of manual labor. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0046] Figure 1 It is a flowchart of the water pump control of the present invention;

[0047] Figure 2 It is a flowchart of the water shortage detection of the present invention;

[0048] Figure 3 It is a flowchart of the static pressure monitoring of the present invention;

[0049] Figure 4 It is a flowchart of the motor control in the water pump of the present invention; DETAILED DESCRIPTION OF THE EMBODIMENTS

[0050] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0051] Embodiment:

[0052] Please refer to Figures 1-4 , the present invention provides a technical solution: A water pump control method without a flow sensor, including the following steps:

[0053] S1. System initialization, set the forced operation time, and set the motor running flag bit;

[0054] S2. Collect the real-time pressure P through a pressure sensor and the real-time temperature T through a temperature sensor;

[0055] S3. Water shortage detection;

[0056] S4. Static pressure monitoring;

[0057] S5. Motor control;

[0058] S6. Determine whether the motor running flag is set. If the motor running flag is set, start the motor; otherwise, stop the motor. The start or stop of the water pump is realized by the start and stop of the motor in the water pump. Therefore, controlling the start and stop of the water pump is equivalent to controlling the start and stop of the motor in the water pump.

[0059] Specifically, in the step S3, the method of water shortage detection is as follows:

[0060] Judge whether the water pump is running; if the water pump is in the running state, judge whether the real-time pressure P is less than the water shortage pressure Pw and the duration is greater than or equal to the set time Tw; the water shortage pressure Pw and the time Tw are set according to actual needs;

[0061] If the real-time pressure P is less than the water shortage pressure Pw and the duration is greater than or equal to the set time Tw, set the water shortage fault;

[0062] Otherwise, judge whether the real-time pressure P is less than the system minimum pressure Pi; the system minimum pressure Pi is set according to needs;

[0063] If the real-time pressure P is less than the system minimum pressure Pi, then judge whether the difference between the real-time temperature T and the starting temperature Tb is greater than the threshold value Tx. If the difference between the real-time temperature T and the starting temperature Tb is greater than the threshold value Tx, set the water shortage fault. The threshold value Tx is set according to needs;

[0064] When the water supply network is short of water and the water use is stopped, the water pump will compress air to make the real-time pressure P rise to a normal threshold value X, and this threshold value X is less than the system minimum pressure Pi. At the same time, when compressing air, the air temperature in the water pump will also rise, that is, the real-time temperature T rises. By judging the difference between the real-time temperature T and the starting temperature Tb, the water pump can still be stopped normally when the water supply network is short of water and the water use is stopped;

[0065] Specifically, in the step S4, the method of static pressure monitoring is as follows:

[0066] Judge whether the water pump is running;

[0067] If the water pump is in the stopped state, judge whether the static pressure rising flag is set. If the static pressure rising flag is not set, judge whether the stable pressure cache value Ph is 0;

[0068] If the stable pressure cache value Ph is 0, determine whether the real-time pressure P has been stable for a set duration Th. If the real-time pressure P is stable within the set time Th, save the stable pressure cache value Ph equal to the real-time pressure P; the initial values of the duration Th and the stable pressure cache value Ph are set as needed.

[0069] If the stable pressure cache value Ph is not 0, determine whether the difference between the real-time pressure P and the stable pressure cache value Ph is greater than the threshold Phx. If the difference between the real-time pressure P and the stable pressure cache value Ph is greater than the threshold Phx, set the static pressure rise flag. The threshold Phx is set as needed.

[0070] When the water pump stops, when it is detected that the real-time pressure P rises by more than a threshold Phx, start the water pump, which can prevent the static pressure of the pipe network from being greater than the starting pressure and causing the water pump to fail to start when using water; at the same time, when the water supply resumes after water shortage, the static pressure of the pipe network will also rise. Through the above method, the water pump can also be started automatically.

[0071] Specifically, in the step S5, the method of motor control is as follows:

[0072] Determine whether the water pump is running;

[0073] If the water pump is running, determine whether the water pump is in forced operation;

[0074] If the water pump is not in forced operation, then determine whether the real-time pressure P is greater than the difference between the stop pressure Pt minus the threshold Ptx;

[0075] If so, set the cached pressure Pb equal to the real-time pressure P, set the stop pressure Pt equal to the cached pressure Pb, set the start pressure Pq equal to the stop pressure Pt multiplied by the set percentage value Qx, set the stop pressure curve detection, clear the static pressure rise flag, and then, clear the motor running flag bit; the initial values of the stop pressure Pt and the start pressure Pq are set as needed.

[0076] If not, then determine whether the difference between the real-time temperature T and the start temperature Tb is greater than the threshold Tx; the threshold Tx is set as needed;

[0077] If so, set the cached pressure Pb equal to the real-time pressure P, set the stop pressure Pt equal to the cached pressure Pb, set the start pressure Pq equal to the stop pressure Pt multiplied by the set percentage value Qx, set the stop pressure curve detection, clear the static pressure rise flag, and then, clear the motor running flag bit;

[0078] If the water pump stops, determine whether the static pressure rise flag is set; [[ID=(end)]]

[0079] If yes, then set the starting temperature Tb equal to the real-time temperature T, and then set the motor running flag;

[0080] If the static pressure rise flag is not set, determine whether the water shortage fault is set;

[0081] If so, determine whether the water inlet detection is triggered. If so, set the starting temperature Tb equal to the real-time temperature T, and then set the motor running flag;

[0082] If the water shortage fault is not set, determine whether the shutdown pressure curve detection is set;

[0083] If the shutdown pressure curve detection is set, the shutdown pressure curve detection is performed to determine whether the real-time pressure P drop rate Pd is greater than the threshold value Pdx; the threshold value Pdx is set as needed.

[0084] If the real-time pressure P drop rate Pd is greater than the threshold value Pdx, the shutdown pressure is corrected so that the shutdown pressure Pt is equal to the buffer pressure Pb plus the threshold value Ptb, and the startup temperature Tb is set to be equal to the real-time temperature T. Subsequently, the motor running flag is set; the threshold value Ptb is set as needed.

[0085] If the real-time pressure P drop rate Pd is not greater than the threshold value Pdx, it is determined whether to trigger rust removal;

[0086] If the shutdown pressure curve detection is not set, determine whether to trigger rust removal;

[0087] If rust removal is triggered, the starting temperature Tb is set equal to the real-time temperature T, and then the motor running flag is set;

[0088] If rust removal is not triggered, determine whether antifreeze is triggered;

[0089] If yes, then set the starting temperature Tb equal to the real-time temperature T, and then set the motor running flag;

[0090] If antifreeze is not triggered, determine whether the real-time pressure P triggers the starting pressure Pq;

[0091] If so, the starting temperature Tb is set equal to the real-time temperature T, and then the motor running flag is set.

[0092] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0093] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and variations can be made according to the content of this specification. These embodiments are selected and specifically described in this specification to better explain the principles and practical applications of the present invention, so that those skilled in the art can well understand and utilize the present invention. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. A water pump control method without a flow sensor, characterized in that: It includes the following steps: S1. System initialization, set the forced running time, and set the motor running flag bit; S2. Collect the real-time pressure P through a pressure sensor and collect the real-time temperature T through a temperature sensor; S3. Water shortage detection; S4. Static pressure monitoring; S5. Motor control; S6. Judge whether the motor running flag is set. If the motor running flag is set, start the motor; otherwise, stop the motor; In the step S5, the method of motor control is as follows: Judge whether the water pump is running; If the water pump is running, judge whether the water pump is in forced operation; If the water pump is not in forced operation, then judge whether the real-time pressure P is greater than the difference between the shutdown pressure Pt minus the threshold value Ptx; If so, set the buffer pressure Pb equal to the real-time pressure P, set the shutdown pressure Pt equal to the buffer pressure Pb, set the start pressure Pq equal to the shutdown pressure Pt multiplied by the set percentage value Qx, set the shutdown pressure curve detection, clear the static pressure rise flag, and then, clear the motor running flag bit; If not, judge whether the difference between the real-time temperature T and the start temperature Tb is greater than the threshold value Tx; If so, set the buffer pressure Pb equal to the real-time pressure P, set the shutdown pressure Pt equal to the buffer pressure Pb, set the start pressure Pq equal to the shutdown pressure Pt multiplied by the set percentage value Qx, set the shutdown pressure curve detection, clear the static pressure rise flag, and then, clear the motor running flag bit; If the water pump is stopped, judge whether the static pressure rise flag is set; If so, set the start temperature Tb equal to the real-time temperature T, and then, set the motor running flag bit; If the static pressure rise flag is not set, judge whether the water shortage fault is set; If so, judge whether the water inflow detection is triggered. If so, set the start temperature Tb equal to the real-time temperature T, and then, set the motor running flag bit; If the water shortage fault is not set, judge whether the shutdown pressure curve detection is set; If the shutdown pressure curve detection is set, perform the shutdown pressure curve detection and judge whether the real-time pressure P decrease rate Pd is greater than the threshold value Pdx; If the real-time pressure P decrease rate Pd is greater than the threshold value Pdx, correct the shutdown pressure so that the shutdown pressure Pt is equal to the buffer pressure Pb plus the threshold value Ptb, set the start temperature Tb equal to the real-time temperature T, and then, set the motor running flag bit; If the real-time pressure P decrease rate Pd is not greater than the threshold value Pdx, judge whether rust removal is triggered; If the shutdown pressure curve detection is not set, judge whether rust removal is triggered; If rust removal is triggered, set the start temperature Tb equal to the real-time temperature T, and then, set the motor running flag bit; If rust removal is not triggered, judge whether anti-freezing is triggered; If so, set the start temperature Tb equal to the real-time temperature T, and then, set the motor running flag bit; If anti-freezing is not triggered, judge whether the real-time pressure P triggers the start pressure Pq; If so, set the start temperature Tb equal to the real-time temperature T, and then, set the motor running flag bit.

2. The water pump control method without a flow sensor according to claim 1, characterized in that: In the step S3, the method of water shortage detection is as follows: Determine whether the water pump is running; if the water pump is in the running state, determine whether the real-time pressure P is less than the water shortage pressure Pw, and the duration is greater than or equal to the set time Tw; If the real-time pressure P is less than the water shortage pressure Pw and the duration is greater than or equal to the set time Tw, set the water shortage fault; Otherwise, determine whether the real-time pressure P is less than the minimum system pressure Pi; If the real-time pressure P is less than the minimum system pressure Pi, then determine whether the difference between the real-time temperature T and the starting temperature Tb is greater than the threshold value Tx. If the difference between the real-time temperature T and the starting temperature Tb is greater than the threshold value Tx, set the water shortage fault.

3. A water pump control method without a flow sensor according to claim 1, characterized in that: In the step S4, the method for static pressure monitoring is as follows: Determine whether the water pump is running; If the water pump is in the stopped state, determine whether the static pressure rising flag is set. If the static pressure rising flag is not set, determine whether the stable pressure cache value Ph is 0; If the stable pressure cache value Ph is 0, determine whether the real-time pressure P has been stable for the set duration Th. If the real-time pressure P is stable within the set time Th, save the stable pressure cache value Ph equal to the real-time pressure P; If the stable pressure cache value Ph is not 0, determine whether the difference between the real-time pressure P and the stable pressure cache value Ph is greater than the threshold value Phx. If the difference between the real-time pressure P and the stable pressure cache value Ph is greater than the threshold value Phx, set the static pressure rising flag.

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