Patent Application
20200049152
The present invention relates to a pumping system; and more particularly relates to a pumping system having a controller.
In the Variable Speed Pumping application monitoring pump system vibration level and elevated motor temperature have become critical elements to expand pumping system life expediency and reducing the energy consumption. These elements are especially important to be controllable in the pumping application where over speed operation is engaged.
The present invention provides an active pumping vibration control technique for a variable speed pumping system, in which resonances around critical speeds are detected and avoided automatically by adjusting pump speed accordingly. The present invention also provides failure detection and alarm criterions with a real time graphic display.
For an over speed pump operation that is now practiced in some specific applications, both the temperature and overall vibration may be raised. The active pump vibration control may also be applied in these speed regions by checking upon the vibration resonances as well as the overall power spectra rising levels respectively to protect pumps from failure. The system dynamic analysis data is acquired for the pump together with hydronic system and integrated to the control system, which shows the exact relationship between the parts and the bands alarmed, to pin point a failure mode with a specific part for calling a service.
According to some embodiments, the present invention may take the form of apparatus featuring a controller having a signal processor or processing module configured to:
The apparatus may also include one or more of the following features:
The signal processor or processing module may be configured to provide the corresponding signaling as control signaling to adjust the pump speed.
The apparatus may include a variable speed pumping control system.
The controller may include a moving average historic peak detector configured to
The moving average historic peak detector may be a 3-dimensional moving average historic peak detector.
The 3-dimensional pump vibration power spectrum of P with respect to the pump speed of the frequency domain of f and the temperature change difference of ∇T may take the form of the following equation:
P(n,f,∇T)=φ(n,f,∇T), (1)
where the expression φ(n,f,∇T) is a 3-dimensional power spectra distribution with respect to pump speed of n, time and temperature change difference of ∇T, respectively.
The controller may include a moving average historic peak detector configured to obtain moving average historic peaks over frequency of f in the frequency domain, using the equation:
{circumflex over (P)}(ni, ∇T)={circumflex over (φ)}(ni,MAHP(fi±Δf,∇t,∇T)), (2)
where ni=0, . . . , nmax within a speed region, MAHP(fi±Δf,∇t,∇T) is a 3-dimensional moving average historic peak detector with its center frequency at fi which is associated with a given pump speed of ni, and with filter lengths of ±Δf along frequency, ∇t along time, and the temperature change difference of ∇T, where the 3-dimensional power spectra distribution is combined over fractional octave bands with respect to the pump speed of n.
The controller may be configured to implement an active vibration control with respect to the pump speed of n based upon Eq. 2 as follows:
fixing the pump speed of n at a value of ntria, as
n=ntria (3);
determining when a power spectrum jump of Δ{circumflex over (P)} is greater than a power spectra threshold value of Δ{circumflex over (P)}Thr i set for detecting a resonance at a band of i, based upon the relationship:
Δ{circumflex over (P)}≥Δ{circumflex over (P)}Thr i; (4)
defining a temperature criterion as
∇T≥∇Tthr i, (5)
where ∇Tthr i is a temperature change threshold value set up; and
defining the power spectrum jump of Δ{circumflex over (P)} by the equation:
Δ{circumflex over (P)}(ni, ∇T)=abs({circumflex over (φ)}(ni,∇T)−
where Δ{circumflex over (P)} is the power spectrum jump in between {circumflex over (φ)} at speed of ni and ∇T,
The controller may be configured to implement the active vibration control by resuming the pump speed of n whenever there is no resonance triggered if Δ{circumflex over (P)}<Δ{circumflex over (P)}Thr i, and setting the trig flag from “true” to “false”, respectively.
The signal processor or processing module may be configured to provide the corresponding signaling as control signaling to control the operation of a pumping system, including staging/destaging a pump to or from the pumping system.
According to some embodiments, the present invention may include, or take the form of, a method featuring steps for:
receiving, with a controller having a signal processor or processing module, signaling containing information about a relationship between frequencies of pump vibration resonances detected around critical pump speeds and a 3-dimensional pump vibration power spectrum in the frequency domain with respect to pump speed and pump temperature change differences; and
determining, with the controller, corresponding signaling containing information to adjust the pump speed to avoid the pump vibration resonances around the critical pump speeds, based upon the signaling received.
The method may also include one or more of the features set forth herein.
The drawing, which is not necessarily drawn to scale, includes the following Figures:
Similar parts or components in Figures are labeled with similar reference numerals and labels for consistency. Every lead line and associated reference label for every element is not included in every Figure of the drawing to reduce clutter in the drawing as a whole.
Pumps are essential to Heating or cooling facility operation. Pre-engineered Pump Health Monitoring solutions, such as a vibration monitoring system, deliver diagnostics information to predict issues and take corrective action to reduce downtime and maintenance costs.
There are literally dozens of root causes for damage to a pump and related failure, such as cavitation damage, the failure of seals, bearings or other internals, misaligned or imbalanced installation.
Instead of monitoring pump vibration status, the present invention provides an active pumping vibration control technique for a variable speed pumping system, in which resonances around critical speeds are detected and avoided automatically during pumping operation. The failure detection and alarm criterions are proposed as well with the real time graphic display, in which each vibration resonance model is presented.
For an over speed pump operation that is now practiced in some specific applications, both the temperature and overall vibration may be raised. The active pump vibration control proposed above may also be applied in these speed regions by checking upon the vibration resonances as well as the overall power spectra rising levels respectively to protect pumps from failure.
To achieve that, the pump vibration power spectra with respect to pump speed may be obtained by a 3-dimensional moving average historic peak detector with respect to pump speed, frequency and temperature change, respectively. A resonance under a critical speed may then be detected and avoided in real time by adjusting proportional/integral/derivative (pid) speed of drive/pump accordingly.
The solution can include a wireless field network communicating continuous real-time Active vibration control, diagnostics, and application data from wireless measurement instruments to the host system's HMI display and data applications.
A pump active vibration control and health monitoring system S is shown schematically in
The power spectra distribution of P with respect to the pump speed of n, the frequency domain of f as well as the temperature change difference of ∇T, may be represented in the form of
P(n,f,∇T)=φ(n,f,∇T), (1)
where φ(n,f,∇T) is an expression of 3-dimensional power spectra distribution with respect to pump speed, time and temperature change, respectively.
With φ(n,f,∇T), the detailed resonances of the pump vibration with respect to pump speed, frequency and temperature change can be analyzed and each dynamic mode may be identified accordingly.
To achieve the Active vibration control, the pump vibration resonances power spectra of {circumflex over (P)} or {circumflex over (φ)}, with respect to pump speed of n, as well as temperature change of ∇T, may be obtained by a peak detector over frequency of f in the frequency domain, which may be represented as
{circumflex over (P)}(ni,∇T)={circumflex over (φ)}(ni,MAHP(fi±Δf,∇t,∇T)), (2)
where ni=0, . . . nmax within a speed region, MAHP(fi±Δf,∇t,∇T) is a 3-dimensional moving average historic peak detector with its center frequency at fi which is associated with pump speed of ni, and with the filter lengths of ±γf along frequency, ∇t along time, and the temperature change of ∇T, where the power spectra is combined over fractional octave bands with respect to the pump speed of n.
Therefore, the Active vibration control with respect to pump speed of n based upon Eq. 2 may be derived as following.
The pump speed of n may be fixed at a value of ntrig, as
n=ntrig (3)
when the power spectra has a jump of Δ{circumflex over (P)} which is greater than a power spectra threshold value of Δ{circumflex over (P)}Thr i set for detecting a resonance at the band of i, i.e.,
Δ{circumflex over (P)}≥Δ{circumflex over (P)}Thr i, (4)
together with a temperature criterion defined as
∇T≥∇TThr i, (5)
where ∇Tthr i is a temperature change threshold value set up, and Δ{circumflex over (P)} may be defined in form of
Δ{circumflex over (P)}(ni,∇T)=abs({circumflex over (φ)}(ni,∇T)−
where Δ{circumflex over (P)} is the power spectrum jump in between {circumflex over (φ)} at speed of ni, and ∇T,
A trig flag is raised as “true” accordingly.
The pump speed resume to pid control on speed of n, whenever there is no resonance triggered, i.e., Δ{circumflex over (P)}<Δ{circumflex over (P)}Thr i, and the trig flag is set “false”, respectively.
In general, the pump speed is frozen at ntrig momentarily whenever a resonance-trigger signal triggered, and resumes back to the pid function speed control soon after the trigger signal is vanished.
By way of example,
Note that the temperature change threshold condition of Eq. 5 is only for over speed operation to protect the motor and pump failure.
An individual modes failure detection and alarm may be expressed in form of
Δ{circumflex over (P)}(ni,∇T)≥Δ{circumflex over (P)}Thr i, (7)
∇T≥∇Tthr i, (8)
where
Δ{circumflex over (P)}(ni∇T)=abs({circumflex over (φ)}(ni,∇T)−
where {circumflex over (φ)}(ni, ∇T) is the power spectra combined over fractional octave bands with respect to the pump speed of n, and
The failure detection and alarm may be expressed in form of the overall power spectra as
Δ
and
∇T≥∇Tthr all, (11)
Δ{circumflex over (P)}overall=abs(
where
Equations 7-12 may be used for active pump vibration control as well, especially for the over speed operation, when the overall power spectrum averaged over the pump speed may exceed their thresholds set up, while checking upon any resonances to avoid as well the same as for the resonances handled in the normal operation speed region in Equations 3-6.
Varying pump speed may be realized by staging or destaging a pump to pump system to avoid the over vibration introduced by over speeding operation.
In addition, to pin point a failure mode with a specific part, as the best practice for calling a service, the system dynamic analysis for the pump together with hydronic system should be carried out as well, ahead of time. Therefore, the exact relationship of the parts and the bands alarmed are known specifically to the control system.
According to some embodiments, the present invention may include, or take the form of, apparatus 10 featuring a controller 11 having a signal processor or processing module 10a configured to:
The signal processor or processing module 10a may be configured to provide the corresponding signaling as control signaling to adjust the pump speed.
By way of example, the functionality of the controller 11 may be implemented using hardware, software, firmware, or a combination thereof. In a typical software implementation, the controller would include one or more microprocessor-based architectures having, e. g., at least one signal processor or microprocessor like element 10a. A person skilled in the art would be able to program such a microcontroller (or microprocessor)-based implementation to perform the functionality described herein without undue experimentation. The scope of the invention is not intended to be limited to any particular implementation using technology either now known or later developed in the future. The scope of the invention is intended to include implementing the functionality of the processors 10a as stand-alone processor or processor module, as separate processor or processor modules, as well as some combination thereof.
The apparatus 10 and/or controller 11 may also include other signal processor circuits or components 10b, e.g. including memory modules like random access memory (RAM) and/or read only memory (ROM), input/output devices and control, and data and address buses connecting the same, and/or at least one input processor and at least one output processor.
The apparatus 10 may also include other circuitry and components 10c, including sensors for detecting pump speed, pump vibration, pump temperature, e.g., such as accelerometers, thermistors, etc.
By way of example, the 3-dimensional pump vibration power spectrum may be suitably sensed. The sensed signaling may be suitably processed using the modules 3, 4, 5 and 6 in
By way of further example, the functionality of the controller 11 may be implemented in whole or in part in the pump active vibration control C (
The present invention may be implemented in one or more different embodiments, e.g., consistent with that set forth below:
According to some embodiments, the present invention may include, or take the form of, a variable speed pumping control system with active temperature and vibration monitoring and control means having primarily a variable speed pumping control system with active temperature and vibration monitoring and control device, which is capable for active pump vibration control and failure detection for a pumping hydronic system with a VFD drive. The active pump vibration control may be primarily realized by on-operation vibration and temperature elevation detection by voiding the resonance speeds directly and/or simply by alternating pump speed for a certain rising levels based upon their overall vibration power spectra not only for normal operation, but also for over speed pump operation as well.
According to some embodiments, the present invention may include, or take the form of, the active temperature and vibration monitoring and control means having a 3-dimensional moving average historic peak detector, an automatic resonance detector, a pump/drive speed altering module, and a failure mode evaluation module with associated their real time spectra display and alarming of
{circumflex over (P)}(ni,∇T).
According to some embodiments, the present invention may include, or take the form of, the 3-dimensional moving average historic peak detector for the active pumping vibration control and monitoring means having the form of MAHP(fi±Δf,∇T) with its center frequency at fi and the filter lengths of ±Δf along frequency and ∇T along the time. The power spectra may be combined over fractional octave bands with respect to the pump speed of n.
According to some embodiments, the present invention may include, or take the form of, the automatic resonance detector for the active pumping vibration control and monitoring means having the form of Δ{circumflex over (P)}(ni)≥Δ{circumflex over (P)}Thr i and ∇T≥∇Tthri, with Δ{circumflex over (P)}(ni,∇T)=abs({circumflex over (φ)}(ni,∇T)−
Alternatively, according to some embodiments, the present invention may include, or take the form of, the automatic resonance detector for the active pumping vibration control and monitoring means having the form of Δ{circumflex over (P)}overall≥Δ{circumflex over (P)}Thr all and ∇T≥∇Tthr all, with Δ{circumflex over (P)}overall=abs(
Alternatively, according to some embodiments, the present invention may include, or take the form of, the active temperature and vibration monitoring and control means having the active pump vibration control specially for the over speed operation, when the overall power spectrum and temperature may exceed thresholds set up the same as represented in Eqs. 7-12, for avoiding the resonances as well as their overall spectra limits.
According to some embodiments, the present invention may include, or take the form of, the active temperature and vibration monitoring and control means having the graphic real time spectra display and alarming, in which the vibration spectra, the overall power spectra averaged over the pump speed, temperature, as well as their corresponding thresholds are displayed graphically in real time.
According to some embodiments, the present invention may include, or take the form of, the active temperature and vibration monitoring and control means having system dynamic analysis data acquired for the pump together with the hydronic system and integrated to the control system, which shows the exact relationship between the parts and the bands alarmed, to pin point a failure mode with a specific part for calling a service.
According to some embodiments, the present invention may include, or take the form of, the active temperature and vibration monitoring and control means having all close loop or open loop hydronic pumping systems, such as primary pumping systems, secondary pumping systems, water circulating systems, and pressure booster systems. The systems mentioned here may consist of a single zone or multiple zones as well.
According to some embodiments, the present invention may include the vibration sensors, e.g., such as any accelerators, mems sensors, and so forth.
According to some embodiments, the present invention may include control signals transmitting and wiring technologies, e.g., such as all conventional sensing and transmitting means that are used currently in the art, as well as those later developed in the future. Preferably, wireless sensor signal transmission technologies would be optimal and favorable.
According to some embodiments, the present invention may include pumps for the hydronic pumping systems, e.g., such as a single pump, a circulator, a group of parallel ganged pumps or circulators, a group of serial ganged pumps or circulators, or their combinations.
This application forms part of a family of technologies, as follows:
Reference [1]: [911-019-001-2 (F-B&G-1001US)], by Andrew Cheng, James Gu, entitled “Method and Apparatus for Pump Control Using Varying Equivalent System Characteristic Curve, a/k/a an Adaptive Control Curve,” issued as U.S. Pat. No. 8,700,221, on 15 Apr. 2014.
Reference [2]: [911-019-004-2 (F-B&G-X0001 US01)], by Andrew Cheng, James Gu, Graham Scott, entitled “Dynamic Linear Control Methods And Apparatus For Variable Speed Pump Control,” issued as U.S. Pat. No. 10,048,701, on 14 Aug. 2018.
Reference [3]: [ 911-019-012-2 (F-B&G-X0010US01], by Andrew Cheng, James Gu, Graham Scott, entitled “Sensorless Adaptive Pump Control with Self-Calibration Apparatus for Hydronic Pumping Systems” issued as U.S. Pat. No. 9,897,084, on 20 Feb. 2018.
Reference [4]: [ 911-019.015-3 (F-B&G-X0012WO)], by Andrew Cheng, James Gu, Graham Scott, entitled “System and Flow Adaptive Pumping Control Apparatus—A Minimum Pumping Energy Operation Control System vs. Sensorless Application,” issued as U.S. Pat. No. 9,846,416, on 19 Dec. 2017.
Reference [5]: [911-019-019-1 (F-B&G-X0016US], by Andrew Cheng, James Gu, entitled “No Flow Detection Means for Sensorless Pumping Control Applications,” issued as U.S. Pat. No. 10,317,894, on 11 Jun. 2019.
Reference [6]: [911-019-022-2 (F-B&G-X0022US01], by Andrew Cheng, James Gu, Kyle Schoenheit, entitled “Advanced Real Time Graphic Sensorless Energy Saving Pump Control System,” filed on 22 Jul. 2016, and assigned Ser. No. 15/217,070, which claims benefit to provisional application Ser. No. 62/196,355, filed 24 Jul. 2015.
Reference [7]: [911-019-034-1 (F-B&G-X0022US], by Andrew Cheng, Matt Ruffo and Ruff Jordan, entitled “Adaptive Water Level Controls For Water Empty Or Fill Applications,” filed on 21 Mar. 2018, and assigned Ser. No. 15/927,296, which claims benefit to provisional application Ser. No. 62/196,355, filed 21 Mar. 2017.
All of the aforementioned patents and patent applications are incorporated by reference in their entirety.
The embodiments shown and described in detail herein are provided by way of example only; and the scope of the invention is not intended to be limited to the particular configurations, dimensionalities, and/or design details of these parts or elements included herein. In other words, one skilled in the art would appreciate that design changes to these embodiments may be made and such that the resulting embodiments would be different than the embodiments disclosed herein, but would still be within the overall spirit of the present invention.
It should be understood that, unless stated otherwise herein, any of the features, characteristics, alternatives or modifications described regarding a particular embodiment herein may also be applied, used, or incorporated with any other embodiment described herein.
Although the invention has been described and illustrated with respect to exemplary embodiments thereof, the foregoing and various other additions and omissions may be made therein and thereto without departing from the spirit and scope of the present invention.
This application claims benefit to provisional patent application Ser. No. 62/716,027, filed 8 Aug. 2018, which is hereby incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62716027 | Aug 2018 | US |
