Drive protection and management method of booster system

Abstract

The present invention relates to a method for protecting and managing the driving of a boosting system (1) comprising at least two independently operable hydraulic pumps (2), the method comprising the following steps: a plurality of preset parameters are set by a user at each hydraulic pump (2) via an electronic control unit (5), at least one pressure value at a transmission pipeline (7) of each hydraulic pump (2) is detected via at least one pressure sensor, the driving of at least two hydraulic pumps (2) is determined in a sequential and / or synchronous manner by managing and interpolating these preset parameters and at least one pressure value at each hydraulic pump (2) independently for each pump using each electronic control unit (5). The method allows protecting the electric driving of the boosting system by effectively controlling the number of driving times of each pump. The present invention also relates to a boosting system suitable for implementing the method.

Description

Technical Field

[0001] The present invention relates to a drive protection and management method for a pressure boosting system comprising at least two hydraulic pumps, in particular for optimizing the starting and stopping of the hydraulic pumps.

[0002] The method described above finds useful application particularly, but not exclusively, in the field of pumps and booster units equipped with fixed or variable speed motors in both the civil and industrial sectors.

[0003] The invention also relates to a pressure boosting system suitable for implementing the method. Background Art

[0004] In the art, it is known that equipment for pumping liquids, especially domestic or industrial water, is usually equipped with a suitable pressure boosting system or unit, which includes one or more fixed speed and / or variable speed electric pumps for supplying energy to the water distribution network. One or more autoclaves and one or more pressure switches and / or flow meters are connected to the system.

[0005] In small-scale equipment, the autoclave consists of a tank in which an elastic diaphragm separates a first chamber containing the compressed gas from a second chamber connected to the water distribution network. A certain amount of water is thus collected in the chamber connected to the water distribution network, so as to make the operation of the equipment more flexible and avoid too frequent starts and stops of the pump. In fact, when the pressure in the water distribution network decreases, by using the water contained in the second chamber, it is possible to deliver water to the user without the pump starting to operate. The water circulates by the thrust generated by the compressed gas present in the first chamber acting on the diaphragm.

[0006] Delivery continues until a user-defined minimum pressure value is reached in the network, at which point the pressure switch activates the pump to restore the recommended maximum pressure in the network and tank. Once the maximum pressure is reached, the maximum pressure switch switches off the pump.

[0007] It can therefore be understood from this description how the autoclave performs a buffering function, thereby avoiding starting and stopping of the pump too closely in time (which could damage the impeller and the connection connecting the impeller to the shaft).

[0008] However, autoclaves can malfunction due to damage to the elastic diaphragm or to the compressed gas supply system. In these cases, the autoclave loses its buffering effect, so that any user needs to draw even a small amount of water from the network to start the pump. In this case, the pump or pumps included in the booster equipment start and stop suddenly and continuously as the consumption changes, which quickly leads to damage to the electric drive and in particular to the contactors of the motor that operates the electric pump.

[0009] As a result, diffuse damage occurs in all components of the booster equipment and significant deterioration occurs in the steps that deliver the water to the end user.

[0010] Currently, in order to remedy these drawbacks, specific solutions and methods are being sought that allow regulating the drive of the pump by adopting an autonomous and independent booster unit and correspondingly protecting the electric drive of the system.

[0011] In this context, Italian Patent Document No. 0001336166 shows a method and a system for protecting an electric drive in an electric pump, wherein the analog control board of the pump is removed.

[0012] Based on similar principles applied to analog-digital hybrid solutions, US Pat. No. 9,863,425B2 removes the centralized electronic control equipment for managing pressure and flow signals, aiming to simultaneously ensure water delivery according to the user's desired comfort parameters.

[0013] However, these systems do not yet ensure prompt resolution of problems with protecting the electrical drives of the pumps employed.

[0014] Spanish patent document ES2620685B1 proposes another solution for a parallel pump system that operates differently depending on different configurations detected.

[0015] Although advantageous, this solution is particularly complex and not easy to implement when setting up an operational configuration.

[0016] It is therefore an object of the present invention to provide a method which does not produce the disadvantages of the prior art and which allows protecting the electric drive of the boosting system by effectively controlling the number of drives of each pump.

[0017] Another object is to provide a method capable of optimizing the actuation times of a pressure boosting system by using the unique delivery pressure of each pump of the pressure boosting system as data measured in real time.

[0018] Another object is to provide a method which allows the pumps to be used independently of one another while ensuring the overall reliability of the pressure boosting system and minimizing wear on the mechatronic components.

[0019] Another object is to provide a method and system that can be implemented in existing assemblies simply by replacing one or more of the pumps employed.

[0020] Another object is to provide a method and a system which can be used by the user in a quick and highly intuitive manner without requiring particular specific skills.

[0021] Finally, another object is to provide a method and a system that can be implemented in a cost-effective manner. Summary of the invention

[0022] The solution idea on which the invention is based is to provide a method that allows identifying the operation of a supercharging system by minimizing the number of parameters detected in a continuous manner and implementing a derivation algorithm based on a series of preset parameters.

[0023] The above technical problems are solved by a drive protection and management method for a boosting system comprising at least two operably independent hydraulic pumps, the method comprising the following steps: a user sets a plurality of predetermined parameters through an electronic control unit at each hydraulic pump, detects at least one pressure value through at least one pressure sensor at a delivery pipe of each hydraulic pump, and manages and interpolates the preset parameters and at least one pressure value obtained at each hydraulic pump by utilizing each electronic control unit, thereby determining the drive of at least two hydraulic pumps in a sequential and / or synchronous manner.

[0024] Advantageously, the method allows optimizing the number of opening and closing actions of the booster system, minimizing and evenly distributing the wear of the electromechanical components.

[0025] According to a particular embodiment, the method according to the invention further comprises a step of calibrating the pressure boosting system, wherein at least one system maximum pressure is defined and set.

[0026] Advantageously, this avoids possible calibration deviations between pressure sensors present on different pumps of the pressure boosting system.

[0027] Preferably, there is also provided the step of defining an operating range common to all hydraulic pumps of the boosting system.

[0028] Advantageously, this allows further optimization of the degree of wear of the electromechanical components involved in the supercharging system.

[0029] Still preferably, the method according to the invention further comprises the step of generating a temporary index specific to each hydraulic pump.

[0030] Advantageously, the temporary index allows the method update rules to be iterated in a timely manner.

[0031] More preferably, the method according to the invention provides the step of detecting a plurality of pressure values ​​by at least one pressure sensor at the delivery conduit of each hydraulic pump, and calculating at least one first derivative of an interpolation function of the plurality of values ​​by an electronic control unit at each hydraulic pump.

[0032] Advantageously, this calculation allows trends in measured pressure to be determined and the circuit demands required by the user to be met in a timely manner.

[0033] Preferably, the method according to the present invention further comprises the step of identifying and setting a waiting time in the sequential driving of the hydraulic pumps.

[0034] Advantageously, the invention allows obtaining an improved distribution of the switching actions of the pump of the pressure boosting system.

[0035] More preferably, the method further comprises the step of correcting the waiting time set in the electronic control unit at each hydraulic pump by means of a correction constant.

[0036] Advantageously, this constant stored in the installation step allows the waiting time value to be corrected over time according to a prediction function.

[0037] According to a particular embodiment, the method according to the invention also provides for an iterative repetition of at least two steps of the method.

[0038] Advantageously, this aspect allows for continuous updating of boost system status and updating of system response.

[0039] According to an example that does not belong to the claimed invention, the driving protection and management method of the boost pressure system further comprises the step of setting at least one threshold constant and / or at least one minimum operating range between the start pressure and the stop pressure.

[0040] Advantageously, this is particularly effective for implementation in systems that are already controlled by a single control board.

[0041] Preferably, the range of opening and closing is detected and determined by a timer.

[0042] Advantageously, this solution is effective for the aforementioned systems controlled by a single control panel.

[0043] According to another aspect of the present invention, a boosting system is provided, which includes at least two hydraulic pumps, at least one pressure sensor at a delivery pipeline of each hydraulic pump, and an electronic control unit at each hydraulic pump, and the boosting system is suitable for executing the method according to the present invention.

[0044] Advantageously, the system according to the invention allows the protection of internal electromechanical components through a suitable relationship of opening and closing actions.

[0045] Other characteristics and advantages will become more apparent from the following detailed description of a preferred but not the only embodiment of the invention, with reference to the accompanying drawings, given by way of non-limiting example. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In the attached figure:

[0047] Figure 1 A perspective view showing an exemplary pressure boosting system according to a first embodiment of the method of the present invention;

[0048] Figure 2 express Figure 1 A top view of the boost system in FIG.

[0049] Figure 3 express Figure 1 The front view of the boost system in FIG.

[0050] Figure 4 express Figure 1 A side view of the boost system in FIG.

[0051] Figure 5 An example diagram representing the operation of the method according to the present invention;

[0052] Figure 6 A perspective view showing an exemplary boosting system not pertaining to the present invention;

[0053] Figure 7 express Figure 6 A top view of the boost system in FIG.

[0054] Figure 8 express Figure 6 Front view of the boost system in . DETAILED DESCRIPTION

[0055] With reference to the drawings, reference numeral 1 schematically represents throughout a pressure boosting system made in accordance with the present invention.

[0056] Figures 1 to 4 Specifically shown is a booster system 1 comprising two hydraulic pumps 2. As will be more clearly described later, this embodiment is exemplary and non-limiting of the scope of protection defined by the claims. In practice, typically the booster system 1 may provide a number np of associated hydraulic pumps 2.

[0057] Each hydraulic pump 2 includes a motor 3 and a hydraulic unit 4. Each hydraulic pump 2 includes an electronic control unit 5.

[0058] The electric motor 3 and the hydraulic unit 4 are movably coupled via a drive shaft (not shown).

[0059] The electric motor 3 is preferably of the asynchronous two-phase type.

[0060] The liquid suction pipe 6 and the liquid delivery pipe 7 are branched out from the hydraulic unit 4 , and these two pipes are preferably connected to the supply pipe 8 and the distribution pipe 9 of the boosting system 1 respectively through threaded connections.

[0061] exist Figure 1 In the exemplary embodiment of , the motor 3 is transversely coupled to the electric control unit 5. The electric control unit 5 comprises an electronic control board (not shown) and an interface display 10. The electric control unit is powered by a connecting cable 11.

[0062] The electronic control unit 5 also includes a pressure sensor (not shown) connected to the electronic control board. The pressure sensor is suitable for detecting the pressure of the liquid in the liquid delivery pipeline 7 and adjusting the start / stop cycle of the boosting system 1 accordingly. Each hydraulic pump 2 includes a pressure sensor. As will be more clearly described later, the present description is exemplary and not restrictive, the scope of protection being defined by the appended claims.

[0063] The motor 3 is cooled by a cooling fan 12 splined to the drive shaft at the rear cover 13. The cooling fan 12 is housed in a ventilated housing 14 which is coupled to the rear cover 13.

[0064] The electronic control unit 5 is suitable for managing and controlling at least one operating parameter of the hydraulic pump 2 of the boosting system 1 , in particular by detecting a pressure sensor integrated in the structure of the hydraulic pump 2 .

[0065] The variables managed and controlled by the electronic control unit 5 specifically (but not exclusively) include the gauge pressure Hs measured by the pressure sensor of each hydraulic pump 2, the minimum equipment pressure Hmin set by the user, the maximum equipment pressure Hmax set by the user, and the time unit Δt that is fixed and equal for each hydraulic pump 2 during the installation step.

[0066] In addition, the electronic control unit 5 associates a respective temporary number Np with each hydraulic pump 2, the temporary number Np being variable from 1 to np, np varying according to specific circumstances, and each hydraulic pump 2 having an independent index n.

[0067] Furthermore, in the embodiment with sequential opening action, a waiting time Tatt is determined, which is related to the time offset when the sequential opening or closing of the hydraulic pumps 2 of the boosting system 1 occurs.

[0068] A correction constant Kpc is also associated with the waiting time Tatt. This correction constant Kpc makes a predictive correction based on the evolution of the value of the first derivative of the function interpolating the pressure measured by the sensor of each hydraulic pump 2 and the sign of the second derivative. The value of the correction constant Kpc can be stored in a table that can be modified during the installation step of the booster system 1. If distributed withdrawals of the user occur, the value of Kpc will be between zero and 1. On the contrary, in the case of detection of a small withdrawal with minimal pressure loss (for example, in dripping conditions), the value of Kpc is much greater than 1.

[0069] Therefore, the waiting time parameter Tatt for each pump having a respective temporary number Np is determined as TattNp=Kpc*Np*Δt.

[0070] According to the first embodiment, a step of calibrating the boosting system 1 is performed after the steps of installing and setting parameters are completed. In this step, the boosting system 1 is boosted at a maximum pressure Hmax. The maximum pressure Hmax is measured by any hydraulic pump 2 of the np hydraulic pumps included in the boosting system 1. Therefore, the hydraulic pump 2 is set as the reference hydraulic pump of the system, and all pressures measured by the sensor of each pump of the boosting unit are defined as Hmax. This calibration step allows avoiding possible calibration deviations of the pressure sensor of each hydraulic pump 2. A similar calibration step can also be set with respect to the minimum pressure Hmin. In this calibration step, the correction parameter Kpc is set to 1.

[0071] A step of defining an operating range is then provided, the operating range being defined by a maximum pressure Hmax and a minimum pressure Hmin common to all hydraulic pumps 2 of the pressure boosting system 1 .

[0072] The hydraulic pumps 2 different from the reference hydraulic pump are associated with respective temporary numbers Np between 1 and np.

[0073] Once the supercharging system 1 is activated, each pressure sensor detects the gauge pressure Hs, and the electronic control unit 5 determines a function interpolating the trend of the gauge pressure Hs and the first and second derivatives of the interpolated function.

[0074] If the value of the gauge pressure Hs is lower than the minimum pressure Hmin, the hydraulic pump 2 corresponding to the Np value of 1 is started and remains in the on state until the gauge pressure Hs is higher than the maximum pressure Hmax.

[0075] Furthermore, if the first and second derivatives indicate that the pressure in the circuit is increasing, a value greater than 1 is assigned to the correction constant Kpc, which is selected between the listed values ​​according to the slope of the function of the detected gauge pressure Hs. In this case, the hydraulic pump 2 corresponding to an Np value of 1 restores the pressure to the reference state, thereby providing the user with a delivery volume that meets the equipment specifications.

[0076] If the first and second derivatives indicate that the pressure in the circuit is decreasing, a value less than 1 is assigned to the correction constant Kpc, which is selected between the listed values ​​depending on the slope of the function of the detected gauge pressure Hs.

[0077] In this case, the hydraulic pump 2 corresponding to the Np value of 1 will not return the circuit pressure to the reference state, nor will it provide the user with a delivery volume that meets the specifications. Therefore, TattNp can be dynamically modified to maximize the user's delivery requirements.

[0078] For a duration equal to TattNp, all pumps remain stably in the Hs monitoring step without being turned on. Only the pumps whose respective temporary number Np is 1 have a waiting time value Tatt of 0.

[0079] Once a shorter observation time has elapsed, i.e. the observation time corresponding to the respective temporary number 2 hydraulic pump 2, if the gauge pressure value Hs measured by the pressure sensor is lower than the maximum pressure Hmax, this hydraulic pump is also turned on. Similarly, the same operation is performed for all other hydraulic pumps 2, the order of which is determined by the value TattNp.

[0080] When the gauge pressure Hs measured by the pressure sensor in each pump is higher than or equal to the maximum pressure Hmax, all hydraulic pumps will be shut down because the entire circuit is pressurized according to the required specifications.

[0081] Once all hydraulic pumps 2 are turned off, the individual indexes of hydraulic pumps 2 are updated according to the following law:

[0082] - If Np = np, then set Np = 1

[0083] - If Np = n, then set Np = n + 1

[0084] The first embodiment described is particularly effective for evenly distributing the wear among the electromechanical components of the hydraulic pump 2 .

[0085] exist Figure 5 In FIG. 1 , a diagram of the operation and performance of a pressure boosting system 1 provided with np pumps of the type just described is shown as a curve Q / H, where Q is the flow required to boost the input and H is the associated hydraulic head. Operating curves with steady, proportional and quadratic H are also shown.

[0086] In a second embodiment of the invention, in an initial step, various temporary numbers Np comprised between the values ​​1 and np are generated and associated in a random manner with each pump, and for each pump, the electronic control unit 5 calculates the waiting time parameter TattNp as already described.

[0087] A pump on and off procedure similar to that provided in the first embodiment is then performed.

[0088] Once shut down of all pumps is complete, repetition of the iteration is provided.

[0089] In the second embodiment described, it is possible that the respective temporary numbers Np of several hydraulic pumps overlap, so that these hydraulic pumps can be turned on simultaneously. In this case, the operating time is proportionally reduced, thereby improving the distribution of the random process.

[0090] Alternatively, the switching on and off of the hydraulic pump 2 determined by the electronic control unit 5 may be provided based on a range between the maximum pressure Hmax and the minimum pressure Hmin, the range being appropriately offset for each hydraulic pump 2 of the boosting system 1 .

[0091] In this case, a variable defined as "shift", i.e., a threshold constant, is set in the electronic control unit 5 to define the opening and closing range of each hydraulic pump 2. The definition of the opening and closing range is detected and determined by a timer. In addition, a minimum operating range x between the opening pressure and the closing pressure of each hydraulic pump 2 is set to achieve the best distribution of the opening time of each hydraulic pump 2 and reduce the number of starts per hour. The minimum range x is usually, but not limited to, fixed between 1 and 1.5 bar.

[0092] Each hydraulic pump 2 is identified by an identification index ID.

[0093] By defining a suitable threshold constant “shift”, the profile of all operating ranges of the hydraulic pump 2 is set.

[0094] With t representing the measurement tolerance of the pressure sensor, a threshold constant "shift" is fixed which is greater than t and is equal for all hydraulic pumps 2. For each hydraulic pump 2, a start pressure Pstart, a stop pressure Pstop value and a number of pumps np are set.

[0095] The following formula is preferably used, but not exclusively:

[0096] Pstop,i=Pstop–i·shift

[0097] Pstart,i=Pstart+(np-i)shift

[0098] Start with the boundary conditions to be satisfied:

[0099] shift=(Pstop-Pstart-x) / (np-1)

[0100] Shiftmin=t

[0101] Get the operation formula:

[0102] (Pstop,min-Pstart,max)=ΔPmin=t·(np-1)+x

[0103] Based on the identification index ID set by the user, each pump is set according to its own i-th threshold to equally distribute the operating pressure range. In order to subject the pumps to similar degrees of wear, the operation alternation of the hydraulic pump 2 is obtained by appropriately exchanging the reference index ID of each hydraulic pump. In fact, while making each pump completely independent of each other, the power supply network voltage cycle of the booster unit 1 as a clock function is preferably used as a synchronization signal for exchanging the identification index ID. The power supply network voltage cycle is measured by calculating the sinusoidal voltage peak. The preferred but not exclusive choice of this signal makes the synchronization very strong, because even in the case of network frequency fluctuations, the hydraulic pumps will remain synchronized and all are subject to the same fluctuations.

[0104] Therefore, the operation time of the single hydraulic pump 2 is calculated, and the index ID exchange is selected accordingly.

[0105] Alternatively, a microcontroller with an integrated RTC (Real Time Clock) may be used.

[0106] exist Figures 6 to 8 , a boosting system 1 not belonging to the claimed invention is shown, the boosting system 1 comprising three hydraulic pumps 2, wherein a reference hydraulic pump 2 and two interlocking hydraulic pumps 15 powered by an electronic control unit 5 of the hydraulic pump 2 operate in the method described above. The interlocking hydraulic pumps 15 are connected to a single reference hydraulic pump 2 via a connecting pipe 16.

[0107] Advantageously, the invention allows minimizing the number of actuations of the booster system, thus protecting the electromechanical equipment involved.

[0108] Furthermore, the method according to the invention allows to employ only one measured physical parameter (eg pressure), thereby minimizing problems caused by possible measurement errors.

[0109] Furthermore, the invention allows to produce in a cost-effective manner an efficient pressure boosting system with mutually independent hydraulic pumps.

[0110] Those skilled in the art will also understand how the present invention can be implemented in existing components without specific conditions.

[0111] It will be understood by those skilled in the art that, according to specific and contingent requirements, the embodiments presented may be subjected to numerous modifications and variations, all of which fall within the scope of protection of the invention as defined by the claims.

Claims

1. A method for drive protection and management of a booster system (1) comprising at least two independently operable hydraulic pumps (2), the method comprising the following steps: - a user sets a plurality of preset parameters at each of the hydraulic pumps (2) through the electronic control unit (5); the preset parameters at least include a minimum pressure (Hmin) and a maximum pressure (Hmax); - detecting at least one gauge pressure value (Hs) at the delivery pipe (7) of each of the hydraulic pumps (2) by means of at least one pressure sensor; - determining the driving of the at least two hydraulic pumps (2) in a sequential and / or synchronous manner, comprising the following steps: Step 1: Associating a separate temporary number (Np) with each hydraulic pump (2), the separate temporary number varying from 1 to np, np being the number of the at least two independently operable hydraulic pumps (2), and n being the separate index of each hydraulic pump (2); Step 2: Each pressure sensor detects a gauge pressure (Hs), and the electronic control unit (5) determines the trend of the gauge pressure (Hs) and the first and second derivatives of the gauge pressure (Hs); Step 3: If the value of the gauge pressure (Hs) is lower than the minimum pressure (Hmin), the hydraulic pump (2) corresponding to the value 1 of the temporary number (Np) is started; Step 4: Determine and set a waiting time (Tatt) in the sequential driving of the at least two independently operable hydraulic pumps (2); Step 5: If the first-order derivative and the second-order derivative indicate that the gauge pressure (Hs) in the circuit is increasing, the hydraulic pump (2) corresponding to the temporary number (Np) value of 1 restores the pressure to a reference state; Step 6: If the first-order derivative and the second-order derivative indicate that the gauge pressure (Hs) in the circuit is decreasing, once the waiting time (Tatt) has elapsed, i.e., the waiting time (Tatt) of the hydraulic pump (2) with a single temporary number and a value of 2 has elapsed, if the gauge pressure (Hs) measured by the pressure sensor is lower than the maximum pressure (Hmax), the hydraulic pump (2) with a single temporary number and a value of 2 will also be turned on; Step 7: Repeat steps 2 to 6 for all hydraulic pumps (2); - Once the gauge pressure (Hs) measured by the pressure sensor in each pump is higher than or equal to the maximum pressure (Hmax), all hydraulic pumps (2) are shut down and the individual temporary number (Np) is updated as follows: - If Np = np, then set Np = 1 - If Np = n, then set Np = n + 1 - Continue at step 2.

2. The method for driving protection and management of the boosting system (1) according to claim 1 also includes a step of correcting the waiting time by a correction constant (Kpc), and the correction constant is set in the electronic control unit (5) at each of the hydraulic pumps (2).

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