Method for exchanging information between external receiver and pump

Abstract

The invention relates to a method for exchanging information between an external receiver and a pump comprising an electric motor as a pump drive and a frequency converter for controlling the rotational speed of the motor, in which an acoustic information signal that can be detected by the external receiver is generated by the pump. At least one operating parameter of the frequency converter varies during the conventional pump operation such that the pump emits an acoustic information signal (20) that can be detected by an external receiver during the conventional pump operation.

Description

Technical Field

[0001] The present invention relates to a method for exchanging information between an external receiver and a pump, the pump including an electric motor as a pump driver and an inverter for controlling the rotational speed regulation of the motor, wherein an acoustic information signal that can be detected by the external receiver is generated by the pump. Background Art

[0002] Today, for efficiency reasons, modern pumps (such as heating circulation pumps) operate in a rotational speed regulation manner. The pump driver in the form of an electric motor is fed by means of an inverter. The output voltage generated by the inverter can be varied for rotational speed adaptation, and the output voltage is supplied to the electric motor as the motor voltage.

[0003] In addition, in addition to the energy-efficient control of the pump, it is becoming increasingly important to create a communication connection between the pump and at least one external receiver for the purpose of exchanging information. The external receiver can be a central control or management unit, or can simply be a commercially available smartphone or tablet on which an application for communicating with the pump runs. The operating data of the pump should be transmitted via this interface for external monitoring, management, or control. In order for the pump to communicate, separate communication hardware needs to be integrated into the pump. For example, the integration of a Bluetooth communication module is known, but this increases the production cost of the pump. Summary of the Invention

[0004] The object of the present invention is to create a simple and cost-appropriate pump communication option.

[0005] This object is achieved by a method for exchanging information between an external receiver and a pump according to the features of claim 1. Advantageous embodiments of the method are the subject matter of the dependent claims. In addition, this object is achieved by a pump according to the features of claim 12.

[0006] Starting from a known pump having an electric motor and an inverter for regulating the rotational speed of the pump, it is proposed to dispense with separate hardware for communicating with at least one external receiver. Instead, the existing hardware of the inverter is used for communication purposes in a repurposed manner, which is achieved by adapting the control of the inverter; in particular, the software-based inverter control logic can be simply adapted.

[0007] According to the present invention, it is specifically proposed that at least one operating parameter of the inverter changes during continuous pump operation, such that the pump generates a dedicated acoustic signal during continuous pump operation that can be clearly detected by the external receiver. Simply put, by specifically modifying the motor control, the conventional operating noise of the pump is specifically changed so that this can be recognized by the external receiver, wherein the modification does not significantly affect the rotational speed regulation.

[0008] In this way, a simple option for exchanging information between the pump and any desired receiver can be realized. For most applications, the option thus created is sufficient, for example, to signal alarms or other pump conditions or states. Existing pumps do not require any hardware additions; instead, a programmatic adaptation of the frequency converter is sufficient. Existing pumps can thus also be modified subsequently and retrofitted with the communication option.

[0009] When implementing this method, it should be noted that in an ideal situation, changes in the operating parameters of the frequency converter do not affect or at least only slightly affect the normal pump function.

[0010] According to an advantageous embodiment, for example, the generated output voltage of the frequency converter, i.e. the motor feed voltage, can be varied, thereby generating a detectable acoustic signal. For the normal operation of the pump motor, a motor voltage with a variable fundamental frequency and amplitude is generated at the output of the frequency converter. Preferably, for example, the voltage or a voltage curve with a frequency higher than the fundamental frequency can be fed in, i.e., a so-called high-voltage injection can be performed by appropriately controlling the frequency converter. By appropriately feeding a high-frequency voltage curve into the fundamental frequency motor voltage, a definable acoustic signal can be generated during the continuous operation of the pump, which acoustic signal can be detected by a receiver. This additional frequency modulation of the motor voltage does not affect the normal operation of the pump, or only slightly affects it, so that the pump still operates normally. By generating an acoustic signal by high-frequency injection, the pump can therefore output an acoustic indication as required, which can be detected by a terminal device equipped with an acoustic receiver.

[0011] Instead of the option of high-frequency injection, in an advantageous embodiment of the invention it is proposed to modify the switching frequency of the built-in switching elements of the inverter module for switching the frequency converter. Adapting the switching frequency generally does not influence the generated output voltage, but leads to deviations in the acoustic operating noise of the pump, which in turn can be detected by the receiver as an information signal. For example, it is conceivable that the switching element is initially switched at a generally constant reference switching frequency. If information is transmitted from the pump to the receiver, the switching frequency is preferably increased or reduced by a defined amount. Deviations of the current switching frequency from the original reference switching frequency can be detected acoustically and thus recognized by the receiver. For example, in the case of an original reference switching frequency of 16 kHz, by reducing the switching frequency to 15 kHz, information, such as an alarm, can be signaled from the pump to the receiver.

[0012] According to a preferred embodiment of the invention, the defined change in the switching frequency can also be used to transmit a binary data sequence from the pump to the receiver. For this purpose, the change in the switching frequency must be clocked, i.e. the change in the switching frequency must take place at a defined time. If the receiver is synchronized with the time rate of change, the binary data sequence can be transmitted from the pump to the receiver.

[0013] The use of the method for transmitting information according to the invention can be used for different application purposes, where information is to be transmitted from a pump to at least one receiver. For example, it can be considered that the pump transmits its current state by means of this method. For example, the normal operating state of the pump is signaled by the pump operation without modifying the frequency converter operating parameters, while during operation with modified operating parameters and thus generating an acoustic signal, an abnormality in the pump behavior should be indicated.

[0014] In practice, pump manufacturers are usually interested in registering the pumps used by customers, i.e., the pump manufacturer can clearly link the pump to a specific customer identifier so that dedicated customer service can be provided thereby. Here, for example, it is advantageous that; an acoustic signal is generated by modifying the operating parameters, thereby indicating to the receiving device whether the pump has been registered at the manufacturer. In this way, a dedicated application executed on a smartphone, tablet or laptop can detect the acoustic signal in the reception area and assist the user automatically when registering the pump. The application can also indicate to the customer whether the pump is operating normally or whether there may be an error.

[0015] For detecting and evaluating the acoustic signal, an external receiving device preferably uses a built-in, commercially available microphone. By performing audio analysis on the recorded audio signal, especially by means of frequency analysis such as the Fast Fourier Transform (FFT) or the Discrete Fourier Transform (DFT), the application executed on the device can extract the transmitted information from the recorded audio signal.

[0016] The acoustic signal generated by means of this method can be heard by humans, so that in principle no technical device is required to transmit the information, but the user can already recognize and ideally evaluate the changed operating noise of the pump. However, there is no objection to choosing a modification of the operating parameters such that the operating noise, i.e., the change in the generated acoustic signal, is not perceptible to humans.

[0017] In addition to the method according to the invention, the invention also relates to a pump, in particular a centrifugal pump, which pump comprises an electric motor and a frequency converter for variably adjusting the electric motor. According to the invention, the frequency converter, in particular the control device of the frequency converter, is configured to perform the steps of the method according to the invention. Thus, the same advantages and features as already discussed above according to the method are obtained for the pump according to the invention. For the sake of simplicity, repeated explanations are omitted.

[0018] The pump can be a heating circulation pump, a circulation pump for a pressurization facility or other centrifugal pump. The electric motor is an inverter-controlled alternating current electric motor or a three-phase electric motor. Generally, this method can be used for any type of motor controlled by a frequency converter, such as synchronous and asynchronous motors, reluctance motors, synchronous reluctance motors, etc. Description of the Drawings

[0019] Next, further advantages and features of the present invention will be explained in more detail based on the application steps described in the figures. Among them:

[0020] Figure 1 A schematic sketch showing the method steps according to the first application scenario, and

[0021] Figure 2 A sketch showing the schematic steps during the second application scenario. Detailed implementation

[0022] A possible application scenario of the method according to the present invention is described below. The pump 1 shown here is a heating circulation pump installed in the heating facility of a customer 5. The heating circulation pump 1 includes an electric motor, and the electric motor is regulated in an energy-efficient manner by means of an integrated frequency converter. Here, the method according to the present invention is used to: output the status information of the hardware of the pump 1, and then the status information can be detected by any terminal device 2. In a specific embodiment, the status information (hereinafter referred to as "acoustic red or green light") indicates whether the pump 1 has been registered with the pump manufacturer 3. Figure 1 The sketch shows the schematic steps of the registration process.

[0023] Step 1:

[0024] In the delivered state of the pump 1, the pump emits an acoustic signal 20 ("acoustic red light"), which can be recognized via the microphone of the smartphone 2, and the acoustic signal contains the device ID of the pump 1. The acoustic signal 20 is generated by changing the operating parameters of the built-in frequency converter of the pump 1 by means of the method according to the present invention.

[0025] In addition to the voltage curve of the fundamental frequency required for running the motor, there is an option here to generate an additional high-frequency voltage curve by means of the so-called high-frequency injection. The high-frequency voltage curve can be fed in such that an acoustic signal 20 is formed, which can be detected and evaluated by the smartphone 2 and the application installed therein. In particular, the application performs real-time FFT analysis on the signal previously recorded via the microphone of the smartphone.

[0026] Instead, it is possible to generate an acoustically detectable or perceivable signal 20 by changing the switching frequency of the frequency converter, such that the deviation from a fixed reference frequency can be used to transmit information. For example, in the case of a reference switching frequency of 16 kHz, a switching frequency of 15 kHz can signal that pump 1 is not registered ("acoustic red light"). Here, the base frequency of the actual operation of the motor is typically in the range of 50 Hz to 300 Hz and is not affected by the change in the switching frequency. If a fixed time window is specified for the change between two or even more switching frequencies, it is possible to form and send basic digital information such as the device ID in the form of binary "1"s and "0"s as a "broadcast".

[0027] When the corresponding application is executed on the smartphone 2, the acoustic signal 20 can be evaluated and pump 1 can be identified as an unregistered pump. In addition, the acoustic signal 20 can already contain the device ID of pump 1, and the smartphone 2 can receive the device ID and use it in a further process.

[0028] Step 2:

[0029] After receiving the device ID of pump 1 via the smartphone 2, the user 5 is guided via the application of the smartphone 2 to register pump 1 online. Here, the connection between the smartphone 2 and the cloud 3 can be at least partially via a mobile communication standard, such as LTE or WLAN. The device ID is transmitted to the cloud service 3 of the pump manufacturer and associated with the customer ID there.

[0030] Step 3:

[0031] After providing the customer ID and linking it to the device ID, the customer ID is then transmitted to pump 1 via an optional additional digital communication connection between the smartphone 2 and pump 1 according to the Bluetooth / Low Energy Bluetooth standard. The generated acoustic signal 20 of pump 1 becomes an "acoustic green light", for example by resetting the change in the operating parameters. However, transmitting the customer ID to pump 1 is only optional; alternatively, pump 1 can also indicate a successful registration by a manual input at the pump control panel.

[0032] Step 4:

[0033] The registered pump 1 sends the identifier of its health value 4 to the application of the smartphone 2 either via the acoustic signal 20 as well or preferably via the established Bluetooth connection.

[0034] Step 5:

[0035] The health value 4 is sent from the smartphone 2 to the cloud 3. In the cloud 3, the submitted health value 4 of pump 1 is compared with the health values 7 of an anonymous group 10 of similar pump models. Then, the customer 5 obtains an assessment 6 of its own pump 1 compared to the anonymous group 10.

[0036] Step 6:

[0037] In the event of interference or an anomaly, the acoustic signal 20 is used again in order to make the customer 5 aware of the anomaly of the pump 1. The acoustic "green light flashing" then signals the anomaly. The service 11 can now proactively contact the customer 5 using the known customer ID and service the pump 1.

[0038] Figure 2 Shows a modified application scenario of the method according to the invention. Different from the first scenario according to Figure 1 in the use case according to Figure 2 interference ("red light") has already occurred in a pump that has not yet been registered. The pump 1 can here: autonomously recognize the anomaly even without being connected to the cloud 3. After detecting the anomaly of the pump 1, an acoustic signal is used in order to make the customer aware of the pump 1. If the acoustic signal is recognized by the smartphone 2, the registration process should also be carried out here in order to link the clear device ID of the pump 1 with the customer ID and thus enable customer-specific services to be provided.

Claims

1. A method for exchanging information between an external receiver (2) and a pump (1), the pump comprising an electric motor as a pump driver and an inverter for controlling the rotational speed regulation of the motor, wherein an acoustic information signal (20) capable of being detected by the external receiver (2) is generated by the pump (1). Characterized in that At least one operating parameter of the frequency converter changes during normal pump operation, such that the pump (1) emits an acoustic information signal (20) during normal pump operation that can be detected by the external receiver (2).

2. The method according to claim 1, characterized in that The at least one operating parameter is the motor voltage generated at the output of the frequency converter.

3. The method according to claim 2, characterized in that A high-frequency voltage is modulated onto the generated motor voltage by means of the frequency converter, and the high-frequency voltage generates an acoustic signal (20) during pump operation that can be detected by the receiver (2).

4. The method according to claim 1, characterized in that The switching frequency of the integrated inverter of the frequency converter changes as an operating parameter, thereby generating an acoustic information signal (20) that can be detected during normal pump operation.

5. The method according to claim 4, characterized in that The information content of the acoustic signal (20) is determined by the deviation of the changed switching frequency of the frequency converter from the original switching frequency.

6. The method according to claim 4 or 5, characterized in that Specific information, such as an indicator or a binary value, can be output by means of a defined deviation of the switching frequency from an original reference switching frequency.

7. The method according to any one of claims 4 to 6, characterized in that The change in the switching frequency is carried out in a time-synchronized manner in order to enable the transmission of a binary data sequence.

8. The method according to any one of the preceding claims, characterized in that The information contained in the acoustic information signal (20) includes the state of the pump (1), for example information on whether the pump (1) is operating normally.

9. The method according to any one of the preceding claims, characterized in that The information contained in the acoustic information signal (20) indicates whether the pump (1) has been registered.

10. The method according to any one of the preceding claims, characterized in that The external receiving device (2) records the operating noise of the pump (1) by means of a microphone and extracts the transmitted information by means of audio signal analysis.

11. The method according to claim 10, characterized in that The audio analysis includes a fast Fourier transform or a discrete Fourier transform.

12. The method according to any one of the preceding claims, characterized in that The acoustic information signal (20) is a signal perceptible to humans.

13. A pump (1), in particular a centrifugal pump, having an electric motor and an inverter for regulating the rotational speed variation of the electric motor, characterized in that The frequency converter is configured to carry out the method according to any one of the preceding claims 1 to 12.

Images