CN116792945A

CN116792945A - Heating system fault prediction method and device and electric water heater

Info

Publication number: CN116792945A
Application number: CN202310820965.4A
Authority: CN
Inventors: 陈涛; 刘书锋; 马鸿飞
Original assignee: AO Smith China Water Heater Co Ltd
Current assignee: AO Smith China Water Heater Co Ltd
Priority date: 2023-07-05
Filing date: 2023-07-05
Publication date: 2023-09-22

Abstract

The embodiment of the application discloses a heating system fault prediction method, a device and an electric water heater, wherein the heating system comprises an electric parameter detector and at least one heating unit, the heating unit comprises a heating element and a first switch for controlling the starting and stopping of the heating element, the electric parameter detector is used for detecting the electric parameter of a power supply line of the heating element, and the method comprises the following steps: executing a first operation of opening the first switch when a predetermined condition is satisfied; and acquiring the time period from the execution of the first operation to the detection of the change of the electrical parameter by the electrical parameter detector exceeding a preset value, and generating a fault prediction signal when the time period is not less than a first preset time period. According to the embodiment of the application, the possibility of failure of the switch can be predicted in advance, so that maintenance personnel can timely maintain or maintain the switch before the switch is really failed, and the service life of the heating system is prolonged.

Description

Heating system fault prediction method and device and electric water heater

Technical Field

The embodiment of the application relates to the field of fault diagnosis, in particular to a heating system fault prediction method and device and an electric water heater.

Background

The heating element of an electric water heater is usually started and stopped by a switch, and for electrical equipment such as a switch, the normal closing and opening of contacts of the electrical equipment are key to ensuring the normal operation of the heating element.

It should be noted that the foregoing description of the background art is only for the purpose of providing a clear and complete description of the technical solution of the present application and is presented for the convenience of understanding by those skilled in the art. The above-described solutions are not considered to be known to the person skilled in the art simply because they are set forth in the background of the application section.

Disclosure of Invention

In the related art, whether a switch fails or not can be detected by monitoring the change of the current in the circuit, but no predictive method for the failure of the switch exists at present, so that whether the switch has failure risk cannot be predicted in advance at present.

In view of at least one of the above problems, embodiments of the present application provide a heating system fault prediction method, a heating system fault prediction device, and an electric water heater.

The specific technical scheme of the embodiment of the application is as follows:

according to a first aspect of an embodiment of the present application, there is provided a heating system failure prediction method, the heating system including an electrical parameter detector for detecting an electrical parameter of a power supply line of a heating element, and at least one heating unit including the heating element and a first switch for controlling start and stop of the heating element, the method including:

Executing a first operation of opening the first switch when a predetermined condition is satisfied;

and acquiring the time period from the execution of the first operation to the detection of the change of the electrical parameter by the electrical parameter detector exceeding a preset value, and generating a fault prediction signal when the time period is not less than a first preset time period.

Further, the heating system further comprises a temperature controller for detecting the heated water temperature, and the preset condition is met when the water temperature reaches a first preset water temperature.

Further, the electrical parameter detector comprises a current transformer for detecting a current on a power supply rail of the heating element.

Further, the first preset duration is a duration required from the closed state of the first switch to the normal automatic opening of the first switch.

Further, when the duration is not less than a first preset duration, generating the fault prediction signal includes:

when the time length is not smaller than a first preset time length and not larger than a second preset time length, determining that the first switch is abnormally and automatically opened, and generating the fault prediction signal, wherein the second preset time length is longer than the first preset time length.

Further, the fault prediction signal includes a fault early warning signal and/or a system maintenance signal.

Further, the method further comprises:

and when the electric parameter detector does not detect that the change of the electric parameter exceeds a preset value within the duration of a second preset duration, determining that the first switch is adhered, and generating a fault signal, wherein the second preset duration is longer than the first preset duration.

Further, the heating system further comprises a second switch which is arranged on a power supply line of the heating unit and is connected with the first switch in series;

the second preset time period is a predetermined value or the second preset time period is not longer than a time period required from the execution of the first operation to the disconnection of the second switch.

Further, the heating system further comprises a second switch in series with the first switch;

Further, after the first operation is performed, when it is detected that the water temperature heated by the heating system exceeds a second preset water temperature, the second switch is turned off, and the second preset water temperature is greater than the first preset water temperature.

Further, the heating system further comprises a third switch for controlling the second switch to be switched on and off, and when the water temperature heated by the heating system exceeds a third preset water temperature, the third switch is switched from an on state to an off state.

Further, upon determining that the first switch is adhered, the method further comprises: opening the second switch.

Further, the first switch and/or the second switch comprises an ac contactor.

According to a second aspect of the embodiments of the present application, there is provided a heating system failure prediction apparatus including a controller configured to perform the heating system failure prediction method of the first aspect.

According to a third aspect of an embodiment of the present application, there is provided an electric water heater, comprising:

a heating system comprising an electrical parameter detector and at least one heating unit, the heating unit comprising a heating element and a first switch controlling the heating element to start and stop, the electrical parameter detector being used for detecting an electrical parameter of a power supply line of the heating element;

a heating system failure prediction apparatus according to the second aspect;

the heating element is used for heating water in the inner container.

Further, the heating system further includes: and the temperature controller is electrically connected with the controller and used for detecting the heated water temperature, and when the temperature controller detects that the water temperature reaches a first preset water temperature, the controller executes a first operation of switching off the first switch.

Further, the heating system further includes: the second switch is arranged on a power supply line of the heating unit and is connected with the first switch in series;

after the controller executes the first operation, when the temperature controller detects that the water temperature exceeds a second preset water temperature, the controller executes a second operation of turning off the second switch.

Further, the first switch and/or the second switch comprises an ac contactor.

Further, the heating system further comprises a third switch for controlling the second switch to be opened and closed, and the third switch is switched between an on state and an off state according to the change of temperature.

Further, the third switch is a high-temperature limit switch, and when the water temperature heated by the heating system exceeds a third preset water temperature, the third switch is switched from the on state to the off state.

The embodiment of the application has the beneficial effects that: and acquiring the time period from the execution of the first operation to the detection of the change of the electrical parameter by the electrical parameter detector exceeding a preset value, and generating a fault prediction signal when the time period is not less than a first preset time period, thereby predicting the possibility of failure of the switch in advance, so that a maintainer can timely maintain or maintain the switch before the switch is truly failed, and prolonging the service life of the heating system.

Specific embodiments of the application are disclosed in detail below with reference to the following description and drawings, indicating the manner in which the principles of the application may be employed. It should be understood that the embodiments of the application are not limited in scope thereby. The embodiments of the application include many variations, modifications and equivalents within the spirit and scope of the appended claims. Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments in combination with or instead of the features of the other embodiments.

Drawings

The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. In addition, the shapes, proportional sizes, and the like of the respective components in the drawings are merely illustrative for aiding in understanding the present application, and are not particularly limited. Those skilled in the art with access to the teachings of the present application can select a variety of possible shapes and scale sizes to practice the present application as the case may be.

FIG. 1 is a schematic diagram of a heating unit according to an embodiment of the present application;

FIG. 2 is a schematic diagram of a fault prediction method according to an embodiment of the present application;

FIG. 3 is a schematic diagram of a heating unit according to an embodiment of the present application;

FIG. 4 is a schematic diagram of a fault prediction method according to an embodiment of the present application;

FIG. 5 is a schematic diagram of a fault prediction method according to an embodiment of the present application;

FIG. 6 is a schematic diagram of a fault prediction method according to an embodiment of the present application;

FIG. 7 is a schematic diagram of a failure prediction apparatus according to an embodiment of the present application;

fig. 8 is a schematic diagram of an electric water heater according to an embodiment of the present application;

fig. 9 is a schematic diagram of a heating system according to an embodiment of the present application.

Detailed Description

The technical solution of the present application will be described in detail below with reference to the attached drawings and specific embodiments, it should be understood that these embodiments are only for illustrating the present application and not for limiting the scope of the present application, and various modifications of equivalent forms of the present application will fall within the scope of the appended claims after reading the present application.

In the embodiments of the present application, the terms "first," "second," and the like are used to distinguish between different elements from each other by name, but do not indicate spatial arrangement or time sequence of the elements, and the elements should not be limited by the terms. The term "and/or" includes any and all combinations of one or more of the associated listed terms. The terms "comprises," "comprising," "including," "having," and the like, are intended to reference the presence of stated features, elements, components, or groups of components, but do not preclude the presence or addition of one or more other features, elements, components, or groups of components.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

Example of the first aspect

An embodiment of the first aspect of the present application provides a heating system fault prediction method, the heating system including an electrical parameter detector and at least one heating unit, the heating unit including a heating element and a first switch for controlling start and stop of the heating element, the electrical parameter detector being configured to detect an electrical parameter of a power supply line of the heating element. Fig. 1 and 3 are schematic structural diagrams of a heating unit according to an embodiment of the present application, as shown in fig. 1 and 3, the heating system includes at least one (hereinafter referred to as N, for example, n=4) heating unit 101, where N is an integer greater than or equal to 1, and by providing an operating current to the heating unit, the heating unit is heated up to generate heat, so that a heating function can be implemented. For example, the heating element 102 may be a heating rod, the first switch 103 may be an ac contactor, the heating element being in an on state or an off state means that the first switch in the heating unit controlling the heating element is in an on state, and the heating element being in an off state means that the first switch in the heating unit controlling the heating element is in an off state.

In some embodiments, each heating unit may include a first switch and one or more heating elements. For example, when the operating current is a single-phase supply current, the heating system comprises only one phase line, as shown in fig. 1, for a heating unit comprising a first switch and a heating element; when the operating current is a three-phase supply current, as shown in fig. 3, the heating system includes three phase lines, where the three phase lines are a U-phase, a V-phase, and a W-phase, respectively, that is, on each of the three phase lines, for a heating unit, a first switch and heating elements of three different phase line branches are included, where the first switch can control start and stop of the heating elements of the three phase lines at the same time, and here, the description of fault detection is given by taking fig. 1 as an example.

It should be noted that, in the above example, one phase line of each heating unit includes one heating element, but the embodiment of the present application is not limited thereto, and may also include at least two heating elements connected in series, and the like, which are not described herein again.

In some embodiments, an electrical parameter detector is used to detect an electrical parameter of the power supply line of the heating element, which may be a current parameter or a voltage parameter. For example, the electrical parameter detector includes a current transformer (also called a current sensor) for detecting a current on a power supply path of the heating element, and the current transformer is serially arranged on the path of the phase line to obtain the current value of the path, but the embodiment of the present application is not limited thereto, and the electrical parameter detector includes a voltage detector for detecting a voltage across the heating element, which may be arranged across the heating element in parallel, and the position and connection relation of the electrical parameter detector will be described in the following embodiments, taking the electrical parameter detector as an example of the current transformer.

FIG. 2 is a schematic diagram of a fault prediction method according to an embodiment of the present application, as shown in FIG. 2, the method includes:

201, when a predetermined condition is satisfied, performing a first operation of turning off the first switch;

202, acquiring a time period from execution of the first operation to when the change of the electrical parameter detected by the electrical parameter detector exceeds a preset value, and generating a fault prediction signal when the time period is not less than a first preset time period.

In some embodiments, the heating system may be used to heat, and the fault prediction determination may be made when it has completed a predetermined heating task, or in certain operating conditions. For example, the heating system may be used in an electric water heater for heating water, the predetermined condition being met when the heated water temperature reaches a first preset water temperature. For example, the first preset water temperature may be a target water temperature set by a user, that is, when the target water temperature is reached, a first operation of turning off the first switch is performed, so that a failure prediction determination may be performed without affecting normal water consumption of the user, but the embodiment of the present application is not limited thereto, and satisfying the predetermined condition may further include turning on (starting power supply), or satisfying the predetermined condition may further include accumulating a time period during which the heating element operates longer than a preset time period, or a preset period between the execution of the previous failure prediction, and the like, which are not exemplified herein.

In some embodiments, the heating system may further include a temperature controller for detecting a heated water temperature, the water temperature being detected by the temperature controller, and when the water temperature reaches a first preset water temperature, the predetermined condition is satisfied, a first operation of turning off the first switch is performed, that is, the temperature controller may control the turning-off of the first switch. The position and connection relation of the thermostat will be described in the later-described embodiments.

In some embodiments, the heating system may further include a controller and a first relay (the position and connection relationship will be described in the embodiments described later) forming a first circuit (for example, the controller and the first switch are connected by a wire to form a first circuit) on which the first relay and the aforementioned thermostat are disposed for controlling on or off of the first switch. The number of the first relays corresponds to the number of the first switches, that is, one first relay corresponds to one first switch, the corresponding first relay is connected in series with the first switch, the temperature controller can report the detected water temperature to the controller in real time or periodically, when the controller judges that the reported water temperature reaches the first preset water temperature, the controller determines that the condition is met, and first operation is executed, wherein the first operation comprises the following steps: the controller sends an off signal to a first relay corresponding to the first switch, the first relay can be regarded as a relay, and after the first relay is turned off, the first relay stops energizing the first switch, and then the first switch is turned off.

In some embodiments, taking the first switch as an ac contactor as an example, when the first switch fails, if the first switch is energized, the contact will attract the coil, so as to turn on the circuit, if the first switch is stopped to be energized, the contact will not attract the coil any more, so the first switch will also be opened, and after the energization is stopped, a certain time TH is required from the state (closed state) of the contact attracting the coil to the state (automatic open state) of the contact failing to attract the coil, that is, the time TH is a time period required from the closed state of the first switch to the normal automatic open state of the first switch. However, when the first switch fails, for example, when the contact is stuck, if the power supply to the first switch is stopped, the contact still attracts the coil, and the first switch cannot be automatically opened. The "automatic opening of the first switch" referred to hereinafter in the embodiments of the present application means that the first switch is automatically opened when the first relay is opened and the first switch is stopped from being energized, and then the first switch is automatically opened when the first switch is from the contact sucking coil to the contact non-sucking coil.

The inventors have found that when the first switch is likely to fail or likely to fail, if power supply to the first switch is stopped, the length of time required for the first switch to switch from the state of the contact-attracting coil to the state of the contact-non-attracting coil will no longer be TH, and therefore, failure prediction can be made based on this length of time, as will be described in detail below.

In some embodiments, in 202, a time period T that passes from when the first operation is performed to when the change in the electrical parameter detected by the electrical parameter detector exceeds a preset value is acquired, and when the time period T is not less than a first preset time period, a fault prediction signal is generated, for example, the first preset time period may be TH or slightly greater than TH, which is not limited by the present application.

In some embodiments, after the first switch is opened, the load in the circuit may be considered to increase compared to the closed state of the first switch, resulting in a decrease in the main current value (for example, when the first switch is opened, the branch where the heating element is located is in an open state, and the heating element stops operating, thereby causing an increase in the load resistance in the circuit, and thus causing a decrease in the main current), so that, after stopping energizing the first switch, the change in the electrical parameter detected by the electrical parameter detector exceeds a preset value, for example, if the main current value changes, and when the change exceeds the preset value, it is indicated that the first switch is opened, and it is necessary to compare the change in the main current value after compensation and correction with the preset value, which is not an example. The preset value (second preset value) may be less than or equal to a previously detected difference between the dry circuit current value when the first switch is closed and the dry circuit current value when the first switch is opened.

In some embodiments, after the first operation is performed, timing is started, or the moment when the first operation is performed is taken as a time starting point, whether the change of the main current exceeds a preset value is detected, if the change of the main current exceeds the preset value is detected, the first switch is turned off, and then, a time period T from the time starting point to the moment when the change of the main current exceeds the preset value is detected is judged, when the time period T is smaller than a first preset time period, the first switch is automatically turned off, when the time period T is not smaller than the first preset time period, a fault prediction signal is generated, and the fault early warning signal and/or the system maintenance signal, that is, when the time period T is not smaller than the first preset time period, indicate that the first switch is actually turned off automatically for a time longer than a time period required by the first switch to be switched from a closed state to a normal automatic open state, but the first switch is automatically turned off (not broken) as a result, and further indicate that the first switch is likely to be broken or is broken, that a fault is predicted, is realized. Therefore, when the time period T is not less than the first preset time period, the possibility that the first switch is to be failed can be predicted. In addition, the fault prediction signal comprises a fault early warning signal and/or a system maintenance signal, and maintenance personnel can be reminded of timely maintaining or maintaining the switch before the switch really breaks down through the fault prediction signal.

In some embodiments, the heating system further comprises a second switch 104 disposed on a power supply line of the heating unit and in series with the first switch; the controller and the second switch 104 form a second loop (e.g., the controller and the second switch are connected by a wire to form a second loop). By providing a dual switch control of the start and stop of the heating element, the second switch may be opened for circuit protection when the first switch may soon fail or fail, wherein the heating system may further comprise second relays (the position and connection relationship will be described in the following embodiments), the second relays are arranged on the second circuit, the number of the second relays corresponds to the number of the second switches, that is, one second relay corresponds to one second switch, and the corresponding second relays are connected in series with the second switch, but the embodiment of the application is not limited by this, and only one second relay may be provided, and the on and off of all the second switches are controlled by one second relay.

The following describes how to control the on and off of the second switch.

In some embodiments, after performing the first operation, the second switch is turned off when it is detected that the water temperature heated by the heating system exceeds a second preset water temperature, the second preset water temperature being greater than the first preset water temperature. After the first operation of turning off the first switch is performed, as described above, when the first switch may soon fail or fail, the automatic turn-off time will be longer than the normal TH, even the automatic turn-off cannot be performed, at this time, the heating element controlled by the first switch still keeps on, the heating element continuously heats the water (e.g. an electric water heater), the water temperature will be continuously raised, the temperature controller continuously detects and reports the water temperature to the controller, when the controller determines that the water temperature reported by the temperature controller reaches the second preset water temperature, the controller sends an off signal to the second relay corresponding to the second switch, the second relay may be regarded as a relay, after the second relay is turned off, the second relay is equivalent to stopping energizing the second switch, so that the second switch is turned off, and after the second switch, the first switch and the heating element are connected in series, the heating element can be controlled to stop running after the second switch is turned off. Therefore, the circuit can be protected, the overheat of water temperature is avoided, and the damage of the heating element is avoided.

In the above example, the opening of the second switch is actively controlled by the controller, but the embodiment of the present application is not limited thereto. The heating system may further include a third switch for controlling the second switch to be turned on and off, the third switch being disposed on the second circuit, and being switched from an on state to an off state when the water temperature heated by the heating system exceeds a third preset water temperature. The third preset water temperature may be greater than or equal to the second preset water temperature, which is not limited in the embodiment of the present application. The third switch may be a high temperature limit switch, and for a specific implementation manner, reference may be made to the prior art, for example, the high temperature limit switch may be a bimetal temperature switch, where when the water temperature exceeds a third preset water temperature, the thermal expansion coefficient of one metal sheet is greater than that of the other metal sheet, so that the whole bimetal sheet bends to one side, and thus the third switch is turned off, and after the third switch is turned off, the second switch connected in series with the third switch is stopped to be energized, so that the third switch is turned off, that is, in the above manner, the second switch is turned off passively. The position and connection relation of the third switch will be described in the later-described embodiment.

The inventor found that, in the related art, when the third switch and the temperature controller are disposed in the same circuit, and when the first switch fails, even if the third switch is turned off, the first switch cannot be turned off, and then the heating element controlled by the first switch still remains on, and the water (e.g., electric water heater) is continuously heated, so that the water temperature continues to rise. According to the embodiment, the temperature controller and the third switch are respectively arranged on different loops where the first switch and the second switch are located, so that when the first switch is likely to be failed or fails, the second loop is disconnected through the third switch to conduct circuit protection, water temperature overheating is avoided, and damage to the heating element is avoided. In addition, the third switch can also ensure the effective disconnection of the second loop, and even if the controller fails to timely and reliably control the second switch to be disconnected, the second switch is still disconnected through the third switch.

In some embodiments, in 202, to further improve the accuracy of fault prediction and improve the detection speed, it may be determined that the first switch is abnormally opened and the fault prediction signal is generated when the duration T is not less than a first preset duration and not greater than a second preset duration, where the second preset duration is longer than the first preset duration. The second preset time period is a preset value. For example, the second preset time period may be a predetermined value, which is a time period required for switching from the closed state to the automatic opening when the first switch, which is obtained experimentally in advance, has less local adhesion; that is, if no change in the main current exceeds the preset value for the first preset period of time, but if the change in the main current exceeds the preset value for the first preset period of time to the second preset period of time, it indicates that the first switch is likely to fail or fail soon, that is, prediction of the failure is achieved. For example, the first switch may fail or may fail soon, including that the first switch may have a local adhesion, and the first switch may not fail (as described above, the failure refers to stopping power supply to the first switch, the contact still may attract the coil, the first switch may not be automatically opened), and after stopping power supply to the first switch, the first switch may still be automatically opened, but due to the local adhesion, the duration that the first switch is automatically opened may be longer than the duration that the first switch is normally automatically opened but may not be longer than the second preset duration.

The second preset time period is taken as an example of the preset value, and the second preset time period can also be related to the second switch. For example, the second preset time period is not longer than a time period required for executing the first operation until the second switch is turned off, as described above, after executing the first operation for turning off the first switch, when the first switch may soon fail or fail, the automatic turn-off time is longer than the normal TH, even if the first switch cannot be automatically turned off, at this time, the heating element controlled by the first switch still maintains the on state, heating water (for example, an electric water heater) continuously causes the water temperature to continue to rise, when the water temperature exceeds the second preset water temperature, the controller controls to turn off the second switch, when the water temperature exceeds the third preset water temperature, the third switch is turned off to passively turn off the second switch, and the second switch is turned off, so that a change of the electrical parameter detected by the electrical parameter detector exceeds a preset value, when the change of the electrical parameter detected by the electrical parameter detector exceeds the preset value, in other words, when the first switch is turned off, the first switch is automatically turned off, the first switch does not automatically turn off, and the first switch does not automatically turn off, when the first switch exceeds the preset value, which indicates that the first switch does not automatically turn off, and the first switch does not automatically turn off.

As can be seen from the above embodiments, when the second switch exists in the circuit, the change of the electrical parameter exceeding the preset value is not necessarily caused by the automatic disconnection of the first switch, but may also be caused by the disconnection of the second switch, so that it is not possible to accurately predict whether the automatic disconnection of the first switch is abnormal or not only by means of the change of the electrical parameter and the first preset time period, but also by combining the second preset time period.

In some embodiments, in addition to making a prediction of a fault, a determination of a fault may be made, the method further comprising:

203, determining that the first switch is adhered when the electrical parameter detector does not detect that the change of the electrical parameter exceeds a preset value within a second preset duration, and generating a fault signal. That is, the first switch is not automatically turned off within the second preset time period, and therefore, the electrical parameter detector does not detect that the change of the electrical parameter exceeds the preset value, and it is determined that the first switch fails, that is, adhesion occurs. In addition, for example, when the second preset time period is not longer than (for example, equal to) the time period required for executing the first operation until the second switch is turned off, and when the electric parameter detector detects that the change of the electric parameter exceeds the preset value in the time period exceeding the second preset time period, it indicates that the change of the electric parameter detected by the electric parameter detector is caused by the second switch being turned off, the first switch is not automatically turned off in the time period exceeding the second preset time period, it may be determined that the first switch is stuck, and a fault signal is generated,

In some embodiments, upon determining that the first switch is stuck, the method further comprises: opening the second switch. In this embodiment, the controller does not need to control the on/off of the second switch according to the second preset water temperature and the third preset water temperature, but sends an off signal to the second relay corresponding to the second switch when the first switch is determined to be adhered, and after the second relay is disconnected, the second relay is equivalent to stopping energizing the second switch, so that the second switch is disconnected, thereby further increasing the protection measures to disconnect the heating, stopping the heating of the unit, protecting the heating system, and prolonging the service life of the heating system.

Fig. 4 is a schematic diagram of a fault prediction method according to an embodiment of the present application, as shown in fig. 4, and for the scenario in fig. 1, the method includes:

401, executing a first operation of turning off the first switch when the thermostat detects that the water temperature exceeds a first preset water temperature;

in a first preset period from the first operation of turning off the first switch, determining whether the change of the electrical parameter detected by the electrical parameter detector exceeds a preset value, executing 403 when the change exceeds the preset value, otherwise entering 404;

403, determining that the first switch is normal and has no fault;

404, after a first operation of turning off the first switch is performed, exceeding a first preset time period, but within a second preset time period, judging whether the change of the electric parameter detected by the electric parameter detector exceeds a preset value, and when the change exceeds the preset value, performing 405, otherwise entering 406;

405, generating a fault prediction signal;

406, determining that the first switch is stuck and opening the second switch.

Fig. 5 is a schematic diagram of a fault prediction method according to an embodiment of the present application, as shown in fig. 5, and for the scenario in fig. 1, the method includes:

501, when the temperature controller detects that the water temperature exceeds a first preset water temperature, executing a first operation of turning off the first switch;

502, judging whether the change of the electric parameter detected by the electric parameter detector exceeds a preset value within a first preset time period from the first operation of executing the opening of the first switch, executing 503 when the change exceeds the preset value, otherwise entering 504;

503, determining that the first switch is normal and has no fault;

504, when the water temperature exceeds the second preset water temperature or the third preset water temperature, the second switch is turned off (the controller is actively turned off or the third switch is passively triggered);

505, from the first operation of turning off the first switch, exceeding a first preset time period, to the time of turning off the second switch, judging whether the change of the electric parameter detected by the electric parameter detector exceeds a preset value, if so, executing 506, otherwise, entering 507;

506, generating a fault prediction signal;

507, determining a first switch adhesion.

The embodiments 401 to 406 and 501 to 507 are as described above and will not be repeated here.

In the above example, how to perform the failure prediction is illustrated in fig. 1. With respect to the scenario in fig. 3, only the differences will be described below, when N is greater than 1, and when the thermostat detects that the water temperature reaches the first preset water temperature, a first operation of opening the first switch corresponding to each heating unit is performed on the first switch, each first switch has a corresponding first relay, and the embodiment of performing the first operation is as described above, and when each first switch fails, after each first switch is opened, the load in the circuit can be regarded as being increased compared with the closed state of each first switch, resulting in a decrease in the dry circuit current value, and therefore, after the energization of each first switch is stopped, the change of the electrical parameter detected by the electrical parameter detector exceeds a preset value, which indicates that each first switch is opened, and the preset value (first preset value) may be less than or equal to the difference between the dry circuit current value when each first switch is previously detected to be closed and the dry circuit current value when each first switch is opened.

In some embodiments, for a scenario in which N is greater than 1, a time period elapsed from when the first operation is performed to when the change in the electrical parameter detected by the electrical parameter detector exceeds a preset value is acquired, and when the time period is not less than a first preset time period, a failure prediction signal is generated, where only it may be indicated that at least one first switch of the N first switches may be failed, but it cannot be determined which first switch may be failed, then the method further includes: the first operation of turning off each first switch is sequentially executed, and the fault prediction is performed on each first switch by using the methods in the foregoing 202 to 203, and the repetition is not repeated. For example, for the 4 heating units, the first switches KM1 to KM4 are respectively corresponding, when the water temperature reaches a first preset water temperature, the controller controls the first relays of the first switches KM1 to KM4 to be turned off, performs a first operation of turning off the first switches KM1 to KM4, determines whether the change of the electric parameter detected by the electric parameter detector exceeds a preset value (first preset value), acquires a time period elapsed from the execution of the first operation to the time period when the change of the electric parameter detected by the electric parameter detector exceeds the preset value (first preset value) when the change of the electric parameter exceeds the preset value, and generates a failure prediction signal when the time period is not less than the first preset time period. But only determining that a first switch of KM 1-KM 4 is likely to fail, in order to determine which first switch of KM 1-KM 4 is likely to fail, the controller controls the first relays corresponding to the first switches KM1 to be turned off, controls the respective first relays of the first switches KM 2-KM 4 to be turned on, determines whether a change in the electrical parameter detected by the electrical parameter detector exceeds a preset value (a third preset value, corresponding to the respective first switch, a difference between a current detected when the first switch is closed (other switches are all closed) and a current detected when the first switch is opened (other switches are all closed) of KM 1), and when the first relay corresponding to the first switch KM1 is opened to a time when the change in the electrical parameter detected by the electrical parameter detector exceeds a preset value (a third preset value), generates a failure prediction signal indicating that the first switch 1 is likely to fail, determines whether a time length of the first switch corresponding to the first relay corresponding to the first switch is not less than the first preset value (a third preset value), a time length of time when the first relay corresponding to the first switch KM1 is opened (a first relay corresponding to the first switch is opened) is controlled to a time length of time when the first relay corresponding to the first switch KM1 is opened (a third preset value), and a time length of time when the first relay corresponding to the first switch KM1 corresponding to the first relay corresponding to the first switch KM1 is opened is detected to a time of the first relay corresponding to the first relay is not less than the first preset value (a preset value is equal to a time length of 3, and a time corresponding to the first relay corresponding to the first switch 1 is detected to be opened) is detected to be opened or 3 is detected to be opened or a time is equal to a time value corresponding to a value, acquiring the time period from the first relay corresponding to the first switch KM2 to the time period when the change of the electric parameter detected by the electric parameter detector exceeds a preset value (a third preset value), generating a fault prediction signal when the time period is not less than a first preset time period, indicating that the first switch KM2 is likely to be in fault, controlling the first relay corresponding to the first switch KM3 to be disconnected by the controller when the time period is less than the first preset time period, and performing fault prediction on each first switch by analogy.

Fig. 6 is a schematic diagram of a fault prediction method according to an embodiment of the present application, as shown in fig. 6, and for the scenario in fig. 3, the method includes:

601, executing a first operation of turning off all N first switches when the temperature controller detects that the water temperature exceeds a first preset water temperature;

602, in a first preset time period from the first operation of turning off all N first switches, judging whether the change of the electric parameters detected by the electric parameter detector exceeds a first preset value, executing 603 when the change exceeds the first preset value, otherwise entering 604;

603, determining that N first switches are normal and have no faults;

604, from the first operation of turning off the N first switches, exceeding a first preset time period, but within a second preset time period, judging whether the change of the electric parameter detected by the electric parameter detector exceeds a first preset value, if yes, executing 605, otherwise setting p=1, and entering 606;

605, generating a fault prediction signal; let p=1;

606, judging whether P is less than or equal to N, executing 607 when the judgment result is yes, otherwise ending;

607, the controller controls to turn off the first switch KMP, but controls to turn on the other first switches (by controlling the first relays corresponding to the respective first switches);

608, judging whether the change of the electric parameter detected by the electric parameter detector exceeds a second preset value within a first preset time period from the first operation of opening the first switch KMP, executing 609 when the change exceeds the second preset value, otherwise, entering 610;

609, determining that the first switch KMP is normally fault-free;

610, after a first operation of opening the first switch KMP is performed, exceeding a first preset time period, but within a second preset time period, judging whether the change of the electrical parameter detected by the electrical parameter detector exceeds a second preset value, if so, executing 611, otherwise, entering 612;

611 generating a fault prediction signal of the first switch KMP; p+1, and returns to 606;

612, determining that the first switch KMP is attached; p=p+1, and returns to 606.

In some embodiments, the second switch may be turned off after the method described above ends. Alternatively, in 610, when the water temperature exceeds the second preset water temperature or the third preset water temperature, the second switch is turned off (the controller is actively turned off or the third switch is passively triggered), and the second preset time period is equal to the time period required from the execution of the first operation to the turning-off of the second switch, which is not limited in the embodiment of the present application.

It should be noted that fig. 2 and fig. 4 to fig. 6 above only schematically illustrate an embodiment of the present application, but the present application is not limited thereto. For example, the order of execution among the operations may be appropriately adjusted, and other operations may be added or some of the operations may be reduced. Those skilled in the art can make appropriate modifications in light of the above, and are not limited to the descriptions of fig. 2 and fig. 4 to 6 described above.

The above description uses the electrical parameter as the current as an example, and the embodiment when the electrical parameter is the voltage is similar, and will not be illustrated here.

As can be seen from the above embodiments, the time period from the execution of the first operation to the detection of the electrical parameter by the electrical parameter detector exceeding the preset value is acquired, and the failure prediction signal is generated when the time period is not less than the first preset time period, so that the possibility of failure of the switch can be predicted in advance, so that a maintainer can maintain or maintain the switch in time before the switch is actually failed, and the service life of the heating system is prolonged.

In addition, a second switch connected in series with the first switch is arranged in the circuit, and the start and stop of the heating element are controlled by arranging the double switches, so that the second switch can be disconnected for circuit protection when the first switch is likely to fail or fail. Therefore, the circuit can be protected, the overheat of water temperature is avoided, and the damage of the heating element is avoided.

In addition, by designing a second preset time length related to the time when the second switch is disconnected, whether the first switch is disconnected automatically is abnormal or not can be accurately predicted.

Embodiments of the second aspect

An embodiment of the second aspect of the present application provides an apparatus, fig. 7 is a schematic diagram of a heating system failure prediction apparatus according to an embodiment of the present application, fig. 7 is a schematic diagram of a failure prediction apparatus according to an embodiment of the present application, and as shown in fig. 7, a failure prediction apparatus 700 according to an embodiment of the present application may include: at least one interface (not shown in fig. 7), a controller 701, a memory 702; a memory 702 is coupled to the controller 701. Wherein the memory 702 may store various data; a program 703 is also stored for determining a failure, and the program 703 is executed under the control of the controller 701, and various preset thresholds, predetermined conditions, and the like are stored.

In some embodiments, the controller 701 may implement the fault prediction method described in the first aspect embodiment, for example, the controller 701 may be configured to: executing a first operation of opening the first switch when a predetermined condition is satisfied; and acquiring the time period from the execution of the first operation to the detection of the change of the electrical parameter by the electrical parameter detector exceeding a preset value, and generating a fault prediction signal when the time period is not less than a first preset time period. Reference may be made to the foregoing embodiments for a specific implementation of the controller 701, which is not described herein.

It is noted that the fault prediction device 700 may also include the communication module 704, or not necessarily include all of the components shown in fig. 7; in addition, the fault prediction device 700 may further include components not shown in fig. 7, to which reference is made to the related art, and not to be taken as an example, for example, the fault prediction device 700 may further include an electrical parameter detector to which the controller 701 is connected.

In embodiments of the present application, controller 701, also sometimes referred to as a processor or operational control, may include a microcontroller or other processor device and/or logic device, with controller 701 receiving inputs and controlling the operation of the various components of failure prediction device 700.

In an embodiment of the application, the memory 702 may be, for example, one or more of a buffer, a flash memory, a hard drive, a removable media, a volatile memory, a non-volatile memory, or other suitable device. Various information may be stored, and a program for executing the related information may be stored. And the controller 701 can execute the program stored in the memory 702 to realize information storage or processing, and the like. The function of the other components is similar to that of the prior art and will not be described in detail here. The components of the fault prediction device 700 may be implemented by dedicated hardware, firmware, software, or combinations thereof without departing from the scope of the application.

For example, when the heating system is applied to an electric water heater, the controller 701 may be configured separately from the controller of the electric water heater (heating system), for example, the controller 701 may be configured as a chip connected to the controller of the electric water heater (heating system), or the two may be controlled by each other, or the functions of the controller 701 may be integrated into the controller of the electric water heater (heating system) itself, which is not limited by the embodiment of the present application.

Embodiments of the third aspect

Embodiments of a third aspect of the present application provide an electric water heater. The electric water heater may be a commercial electric water heater, but the embodiment of the application is not limited thereto. Fig. 8 is a schematic diagram of an electric water heater according to an embodiment of the application. As shown in fig. 8, the electric water heater 800 includes:

A heating system 801 comprising an electrical parameter detector for detecting an electrical parameter of a power supply line of a heating element and at least one heating unit comprising the heating element and a first switch controlling the start and stop of the heating element;

a heating system failure prediction device 802;

a liner 803, the heating element for heating water in the liner.

In some embodiments, the working current of the heating system 801 may be a single-phase power supply current or a three-phase power supply current, and the specific configuration thereof may be described with reference to fig. 1 and 3 of the first aspect, and the implementation of the heating system fault prediction device 802 may refer to the fault prediction device 700 of the third aspect, which is not described herein.

In some embodiments, the fault prediction device 802 may be configured separately from the controller of the electric water heater (heating system), for example, the fault prediction device 802 may be configured as a chip connected to the controller of the electric water heater (heating system), or the two may be controlled by each other, or the functions of the fault prediction device 802 may be integrated into the controller of the electric water heater (heating system) itself, which is not limited by the embodiment of the present application.

In some embodiments, the fault prediction device is configured to perform the fault prediction method in the embodiment of the first aspect, and may refer to the embodiment of the first aspect, and details are not repeated.

It should be noted that the electric water heater 800 may further include components not shown in fig. 8, and reference may be made to the related art, which is not illustrated herein.

The structure of the heating system 801 is further described below, and the repetition of the embodiment of the first aspect is not repeated. Fig. 9 is a schematic diagram of a heating system according to an embodiment of the present application, as shown in fig. 9, a heating system electrical parameter detector 901 and at least one heating unit 902, where the heating unit includes heating elements 9021 (EH 1 to EH 5) and first switches 9022 (KM 1 to KM 5) for controlling start and stop of the heating elements, and the electrical parameter detector 901 is configured to detect an electrical parameter of a power supply line of the heating elements; for example, the electrical parameter detector 901 comprises a current transformer for detecting the current on the power supply path of the heating element. The electrical parameter detector 901 may be provided on the power supply rail.

In some embodiments, the heating system 801 further comprises: the controller 903, and the first relay 904 that is connected with the controller 903, this first relay 904 still is connected with first switch 9022, and this first relay 904 and first switch 9022 one-to-one are used for controlling the break-make of first switch 9022, and the controller 903 forms first circuit with first switch 9022 (one or more), and this first relay sets up on this first circuit.

In some embodiments, the heating system 801 further comprises: the temperature controller 905 electrically connected to the controller and used for detecting the heated water temperature is provided on the first circuit, and when the temperature controller detects that the water temperature reaches the first preset water temperature, the controller 903 performs a first operation of turning off the first switch, and the specific control manner may refer to the embodiment of the first aspect.

In some embodiments, the heating system 801 further comprises: a second switch 906 provided on a power supply line of the heating unit and connected in series with the first switch; the controller 903 forms a second loop with the second switch 906. When the heating system comprises N heating units, the heating system also comprises N first switches (corresponding to N first relays) and N second switches corresponding to the N first switches one by one, and each second switch is connected with one first switch corresponding to the second switch in series.

In some embodiments, the heating system 801 further comprises: and the second relays 907 are connected with the controller 903 and used for controlling the on-off of the second switches 906, the second relays 907 are arranged in the second loop and are also connected with the second switches 906, the second relays 907 are in one-to-one correspondence with the second switches 906 (i.e. the second relays 907 comprise N, and the second relays 907 are synchronously controlled to be on or off by the controller), or the second relays 907 are used for controlling the on-off of all the second switches 906 (i.e. the second relays comprise 1).

In some embodiments, the controller performs the second operation of opening the second switch when the temperature controller detects that the water temperature exceeds a second preset water temperature after the controller performs the first operation, and may refer to the embodiment of the first aspect.

In some embodiments, the first switch and/or the second switch comprises an ac contactor.

In some embodiments, the heating system 801 further comprises a third switch 908 for controlling the opening and closing of the second switch, the third switch being switched between an on-state and an off-state according to a change in temperature. That is, a third switch 908, which may be a high temperature limit switch, is further provided on the second circuit, and is switched from an on state to an off state when the water temperature heated by the heating system exceeds a third preset water temperature. For specific embodiments reference may be made to the examples of the first aspect.

It is noted that the heating system 801 may further include components not shown in fig. 9, and reference is made to the related art, which is not exemplified here.

The embodiment of the application also provides a computer program, wherein when the program is executed in a fault prediction device or an electric water heater, the program enables the main controller to execute the fault prediction method according to the embodiment of the first aspect.

The embodiment of the application also provides a storage medium storing a computer program, wherein the computer program causes a fault prediction device or an electric water heater to execute the fault prediction method according to the embodiment of the first aspect.

The data transmission apparatus described in connection with the embodiments of the present application may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. For example, one or more of the functional blocks shown in the figures and/or one or more combinations of the functional blocks may correspond to individual software modules or individual hardware modules of the computer program flow. These software modules may correspond to the individual steps shown in fig. 1, respectively. These hardware modules may be implemented, for example, by solidifying the software modules using a Field Programmable Gate Array (FPGA).

A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. A storage medium may be coupled to the processor such that the processor can read information from, and write information to, the storage medium; or the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The software modules may be stored in a memory of the information handling system or in a memory card that is insertable into the information handling system.

One or more of the functional block diagrams depicted in the figures and/or one or more combinations of functional block diagrams may be implemented as a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any suitable combination thereof for use in performing the functions described herein. One or more of the functional block diagrams depicted in the figures and/or one or more combinations of functional block diagrams may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP communication, or any other such configuration.

While the application has been described in connection with specific embodiments, it will be apparent to those skilled in the art that the description is intended to be illustrative and not limiting in scope. Various modifications and alterations of this application will occur to those skilled in the art in light of the spirit and principles of this application, and such modifications and alterations are also within the scope of this application.

Claims

1. A heating system fault prediction method, the heating system comprising an electrical parameter detector and at least one heating unit, the heating unit comprising a heating element and a first switch controlling the start and stop of the heating element, the electrical parameter detector being configured to detect an electrical parameter of a power supply line of the heating element, the method comprising:

2. The method of claim 1, wherein the heating system further comprises a thermostat for detecting a heated water temperature, the predetermined condition being met when the water temperature reaches a first preset water temperature.

3. The method of claim 1, wherein the electrical parameter detector comprises a current transformer for detecting current on a power supply rail of the heating element.

4. The method of claim 1, wherein the first predetermined period of time is a period of time required from a closed state of the first switch to a normal automatic opening of the first switch.

5. The method of any one of claims 1 to 4, wherein generating the fault prediction signal when the time period is not less than a first preset time period comprises:

6. The method of claim 5, wherein the fault prediction signal comprises a fault pre-warning signal and/or a system maintenance signal.

7. The method according to any one of claims 1 to 4, further comprising:

8. The method of claim 5, wherein the heating system further comprises a second switch disposed on a power supply line of the heating unit and in series with the first switch;

9. The method of claim 7, wherein the heating system further comprises a second switch in series with the first switch;

10. The method according to claim 8 or 9, wherein the second switch is turned off when it is detected that the water temperature heated by the heating system exceeds a second preset water temperature, which is greater than the first preset water temperature, after the first operation is performed.

11. The method according to claim 8 or 9, wherein the heating system further comprises a third switch for controlling the second switch to be turned on and off, and the third switch is switched from an on state to an off state when the water temperature heated by the heating system exceeds a third preset water temperature.

12. The method of claim 9, wherein upon determining that the first switch is stuck, the method further comprises: opening the second switch.

13. The method according to claim 1 or 8 or 9, wherein the first switch and/or the second switch comprises an ac contactor.

14. A heating system failure prediction apparatus comprising a controller configured to perform the heating system failure prediction method of any of claims 1-13.

15. An electric water heater, comprising:

the heating system failure prediction apparatus of claim 14;

the heating element is used for heating water in the inner container.

16. The electric water heater of claim 15, wherein the electrical parameter detector includes a current transformer for detecting current on a power supply rail of the heating element.

17. The electric water heater of claim 15, wherein the heating system further comprises: and the temperature controller is electrically connected with the controller and used for detecting the heated water temperature, and when the temperature controller detects that the water temperature reaches a first preset water temperature, the controller executes a first operation of switching off the first switch.

18. The electric water heater of claim 17, wherein the heating system further comprises: the second switch is arranged on a power supply line of the heating unit and is connected with the first switch in series;

19. The electric water heater of claim 15 or 18, wherein the first switch and/or the second switch comprises an ac contactor.

20. The electric water heater of claim 18, wherein the heating system further comprises a third switch for controlling the second switch to open and close, the third switch being switched between an on state and an off state in response to a change in temperature.

21. The electric water heater of claim 20, wherein the third switch is a high temperature limit switch that switches from the on state to the off state when the water temperature after being heated by the heating system exceeds a third preset water temperature.