CN114279055B - Fault detection method and system and air conditioner - Google Patents
Fault detection method and system and air conditioner Download PDFInfo
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- CN114279055B CN114279055B CN202111628180.4A CN202111628180A CN114279055B CN 114279055 B CN114279055 B CN 114279055B CN 202111628180 A CN202111628180 A CN 202111628180A CN 114279055 B CN114279055 B CN 114279055B
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Abstract
The invention discloses a fault detection method, a system and an air conditioner, relating to the technical field of air conditioners, wherein the fault detection system comprises: the circuit comprises a control chip, a current detection circuit and a plurality of comparators; the output end of the current detection circuit is connected with the input end of each comparator, and the output end of each comparator is connected with the control chip; the control chip is used for outputting a driving signal to the stepping motor and determining the working state of the stepping motor according to the driving signal; the current detection circuit is used for detecting the running current of the stepping motor and inputting the running current of the stepping motor into each comparator; the control chip is also used for acquiring level signals output by the comparators and judging whether the stepping motor works abnormally or not based on the working state and the level signals. The invention realizes the self-checking of the fault of the stepping motor, avoids influencing the movement angle of the part driven by the stepping motor, and further avoids influencing the normal operation of the equipment where the stepping motor is positioned.
Description
Technical Field
The invention relates to the technical field of air conditioners, in particular to a fault detection method and system and an air conditioner.
Background
At present, an electronic expansion valve is widely applied to refrigerant flow regulation in an air conditioning unit, the opening regulation of the electronic expansion valve is usually driven according to a stepping motor, the current driving control mode of the stepping motor mainly adopts open-loop control, and when the stepping motor is in short circuit, open circuit or other circuit abnormalities, the movement angle of the expansion valve is wrong, so that the pressure of an air conditioning system is influenced, and the operation of an air conditioner is abnormal.
Disclosure of Invention
In order to solve the problems, the invention provides a fault detection method, a fault detection system and an air conditioner, which realize fault self-detection on a stepping motor, avoid influencing the motion angle of a part driven by the stepping motor, and further avoid influencing the normal operation of equipment where the stepping motor is located.
According to an embodiment of the present invention, in one aspect, a fault detection system is provided, including: the control chip, the current detection circuit and the plurality of comparators are arranged on the circuit board; the output end of the current detection circuit is connected with the input end of each comparator, and the output end of each comparator is connected with the control chip; the control chip is used for outputting a driving signal to the stepping motor and determining the working state of the stepping motor according to the driving signal; wherein the working state comprises a single-phase working state and a two-phase working state; the current detection circuit is used for detecting the running current of the stepping motor and inputting the running current of the stepping motor into each comparator; the comparator is used for outputting a corresponding level signal according to the magnitude relation between the running current and the corresponding reference current; the reference current of each comparator is different, and is related to the theoretical operating current of the stepping motor in different working states; the control chip is further used for obtaining level signals output by the comparators and judging whether the stepping motor works abnormally or not based on the working state and the level signals.
By adopting the technical scheme, the collected running current of the stepping motor is input into the comparator, so that the comparator outputs different level signals according to different running currents, whether the stepping motor breaks down or not can be accurately judged according to the working state of the stepping motor and the level signals fed back by the comparator, the fault self-checking of the stepping motor is realized, the influence on the motion angle of a part driven by the stepping motor is avoided, and the influence on the normal operation of equipment where the stepping motor is located is further avoided.
Preferably, the fault detection system includes: the driving chip is arranged between the control chip and the stepping motor, and the current detection circuit is connected with the control chip so as to detect the operating current of the stepping motor; the control chip is used for determining that the stepping motor and the driving chip work normally when the stepping motor is in a stop working state and the level signals output by the comparators are all low level signals; the control chip is also used for determining that the stepping motor or the driving chip works abnormally when the stepping motor is in a stop working state and the level signal output by the comparator is a high level signal.
By adopting the technical scheme, when the stepping motor stops working, whether the output level signals of the comparator are low levels or not is judged, whether the stepping motor and the driving chip are abnormal or not in the standby state can be accurately determined, whether faults exist or not is further judged, and the accuracy of fault detection of the stepping motor is improved.
Preferably, the method comprises the following steps: the reference current of the first comparator is a first theoretical operating current of the stepping motor in a single-phase working state, and the reference current of the second comparator is a second theoretical operating current of the stepping motor in a two-phase working state; the control chip is used for judging whether a first level signal output by the first comparator and a second level signal output by the second comparator are overturned when the stepping motor is in the single-phase working state, and if the first level signal is a high level signal and the second level signal is a low level signal, the stepping motor and the driving chip are determined to work normally; otherwise, determining that the stepping motor or the driving chip works abnormally.
By adopting the technical scheme, the reference current for turning the output level signals of the first comparator and the second comparator is respectively set as the theoretical operating current when the stepping motor normally operates in a single-phase working state and a two-phase working state, so that the control chip can effectively judge whether the stepping motor works abnormally or not in the single-phase working state according to the output level signals of the first comparator and the second comparator, and the influence on components driven by the stepping motor during working is avoided.
Preferably, the fault detection system further comprises: a third comparator, a reference current of which is a third operating current, the third operating current being greater than the second theoretical operating current; the control chip is used for judging whether the first level signal, the second level signal and a third level signal output by the third comparator are overturned when the stepping motor is in the two-phase working state, and if the first level signal and the second level signal are high level signals and the third level signal is a low level signal, the stepping motor and the driving chip are determined to work normally; otherwise, determining that the stepping motor or the driving chip works abnormally.
By adopting the technical scheme, the reference current of the third comparator is set to be the third running current which is larger than the second theoretical running current, so that the control chip can effectively judge whether the stepping motor works abnormally under the two-phase working state according to the output level signals of the three comparators, and can also detect whether the stepping motor has abnormal large current, thereby avoiding the stepping motor from being burnt due to overlarge current and improving the working reliability and safety of the stepping motor.
Preferably, the fault detection system includes: the voltage detection circuit is used for detecting the working voltage of the stepping motor and transmitting the working voltage to the control chip; the control chip is used for obtaining working voltage of the stepping motor in a normal operation state and determining the first theoretical operation current and the second theoretical operation current based on the working voltage and the direct current resistance of each phase of the stepping motor.
By adopting the technical scheme, the working voltage of the stepping motor in the normal running state is detected, the reference currents of the first comparator and the second comparator are calculated according to the working voltage and the direct current resistance of each phase, the types of the comparators and the selection of components of the negative phase reference circuit of the comparator can be assisted, the comparator can quickly and accurately feed back the current condition of the stepping motor, and the fault detection effectiveness of the fault detection system is ensured.
Preferably, the fault detection system includes: the fault prompting device is connected with the control chip; the control chip is used for controlling the fault prompting equipment to send out fault prompts when the stepping motor works abnormally.
By adopting the technical scheme, the fault prompt is sent when the abnormal work of the stepping motor or the driving chip is determined so as to remind a user to perform fault troubleshooting in time, avoid causing the abnormal work of equipment where the stepping motor is located, and improve the user experience.
According to an embodiment of the present invention, on the other hand, a fault detection method is provided, which is applied to the fault detection system of any one of the first aspect; the fault detection method comprises the following steps: when the control chip outputs a driving signal to the stepping motor, determining the working state of the stepping motor according to the driving signal; wherein the working state comprises a single-phase working state and a two-phase working state; acquiring level signals output by each comparator; the reference current of each comparator is different, and is related to the theoretical operating current of the stepping motor in different working states; and judging whether the stepping motor works abnormally or not based on the working state and each level signal.
Preferably, the step of determining whether the stepping motor is abnormal based on the operating state and each of the level signals includes: when the stepping motor is in a stop working state and the level signals output by the comparators are all low level signals, determining that the stepping motor or the driving chip works normally; and when the stepping motor is in a stop working state and the level signal output by the comparator is a high level signal, determining that the stepping motor or the driving chip works abnormally.
Preferably, the fault detection system includes a first comparator, a second comparator and a third comparator, the reference current of the first comparator is a first theoretical operating current of the stepping motor in a single-phase operating state, the reference current of the second comparator is a second theoretical operating current of the stepping motor in a two-phase operating state, the reference current of the third comparator is a third operating current, and the third operating current is greater than the second theoretical operating current; the step of judging whether the stepping motor works abnormally based on the working state and each level signal comprises the following steps: when the stepping motor is in the single-phase working state, if the first level signal output by the first comparator is a high level signal and the second level signal output by the second comparator and the third level signal output by the third comparator are both low level signals, determining that the stepping motor and the driving chip work normally; otherwise, determining that the stepping motor or the driving chip works abnormally; when the stepping motor is in the two-phase working state, if the first level signal and the second level signal are both high level signals and the third level signal is a low level signal, determining that the stepping motor and the driving chip work normally; otherwise, determining that the stepping motor or the driving chip works abnormally.
According to an embodiment of the present invention, in another aspect, an air conditioner is provided, including the fault detection system of any one of the first aspect, the fault detection system is configured to detect whether a stepping motor driving an electronic expansion valve or an air guide door is working abnormally.
The invention has the following beneficial effects: the working state of the stepping motor is determined, the collected running current of the stepping motor is input into the comparator, so that the comparator outputs different level signals according to different running currents, whether the stepping motor breaks down or not can be accurately judged according to the working state of the stepping motor and the level signals fed back by the comparator, fault self-checking of the stepping motor is achieved, the influence on the motion angle of a part driven by the stepping motor is avoided, and further the influence on the normal running of equipment where the stepping motor is located is avoided.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It should be apparent that the drawings in the following description are merely exemplary, and that other embodiments can be derived from the drawings provided by those of ordinary skill in the art without inventive effort.
The structures, ratios, sizes, and the like shown in the present specification are only used for matching with the contents disclosed in the specification, so as to be understood and read by those skilled in the art, and are not used to limit the conditions that the present invention can be implemented, so that the present invention has no technical significance, and any structural modifications, changes in the ratio relationship, or adjustments of the sizes, without affecting the effects and the achievable by the present invention, should still fall within the range that the technical contents disclosed in the present invention can cover.
FIG. 1 is a schematic structural diagram of a fault detection system according to the present invention;
FIG. 2 is a schematic diagram of another fault detection system provided by the present invention;
fig. 3 is a flowchart of a fault detection method provided in the present invention.
Detailed Description
The present invention is described in terms of particular embodiments, other advantages and features of the invention will become apparent to those skilled in the art from the following disclosure, and it is to be understood that the described embodiments are merely exemplary of the invention and that it is not intended to limit the invention to the particular embodiments disclosed. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.
The present embodiment provides a fault detection system, referring to a schematic structural diagram of the fault detection system shown in fig. 1, the system includes: a control chip 11, a current detection circuit 12, and a plurality of comparators 13 (the number of comparators is 2 or more); as shown in fig. 1, the output terminal of the current detection circuit 12 is connected to the input terminal of each comparator 13, and the output terminal of each comparator 13 is connected to the control chip 11. The control chip can be an integrated circuit chip such as a singlechip.
The control chip 11 is configured to output a driving signal to the stepping motor 14, and determine a working state of the stepping motor 14 according to the driving signal; the working state comprises a single-phase working state and a two-phase working state. The method comprises the steps thatbase:Sub>A stepping motor sequentially circulates inbase:Sub>A forward direction according to four-phase eight-beat A-AB-B-BC-C-CD-D-DA underbase:Sub>A normal working state, sequentially circulates according to D-DC-C-CB-B-BA-A-AD under an opposite phase state,base:Sub>A control chip drives the stepping motor to work through 4 paths of driving signals, when the 4 paths of driving signals are all low level, the working state of the stepping motor is determined to bebase:Sub>A stop working state, when only 1 path of driving signals in the 4 paths of driving signals outputs low level, the working state of the stepping motor is determined to bebase:Sub>A single-phase working state, and when 2 paths of driving signals in the 4 paths of driving signals output low level, the working state of the stepping motor is determined to bebase:Sub>A two-phase working state.
The current detection circuit 12 is configured to detect an operation current of the stepping motor, and input the operation current of the stepping motor to each comparator 13. In a possible implementation manner, the current detection circuit may include a sampling resistor, and may further include an operational amplifier, the sampling resistor collects an operating current of the stepping motor, the sampling resistor is connected to an input terminal of the comparator, and when the operating current of the stepping motor changes, a voltage at the input terminal of the comparator also changes accordingly.
The comparator 13 is used for outputting a corresponding level signal according to the magnitude relation between the running current and the corresponding reference current; the reference currents of the comparators are different (that is, the input voltages of the negative ends of the comparators are not used, and the input voltages corresponding to the positive ends are different when the output level signal is inverted), and the reference currents of the comparators are related to the theoretical operating currents of the stepping motor in different working states. The stepping motor comprises three working states of standby (stop working state), single-phase working and two-phase working, the running current in each working state is different, when the running current of the stepping motor detected by the current detection circuit is different, the voltage input to the positive phase end of the comparator is also different, and the larger the running current of the stepping motor is, the larger the input voltage of the positive phase end of the comparator is.
The control chip 11 is further configured to obtain the level signals output by the comparators 13, and determine whether the stepping motor 14 is working abnormally based on the working state and the level signals. Because the comparator outputs a high level signal when the input voltage of the positive phase end is greater than the input voltage of the negative phase end, and outputs a low level signal when the input voltage of the positive phase end is less than the input voltage of the negative phase end, the range of the operating current of the stepping motor can be judged according to the level signals output by the comparators by arranging the comparators with different reference currents.
The above-mentioned fault detection system that this embodiment provided, through the operating condition who confirms step motor to during the operating current input comparator of step motor who will gather, so that the comparator outputs different level signals according to the operating current of difference, can accurately judge whether step motor has taken place the trouble according to step motor's operating condition and the level signal that the comparator fed back, realized the trouble self-checking to step motor, avoid influencing the motion angle of step motor driven part, and then avoid influencing the normal operating of step motor place equipment.
In a possible embodiment, as shown in fig. 1, the fault detection system may further include a driving chip 15 (i.e., a stepping motor driving IC), the driving chip 15 is disposed between the control chip 11 and the stepping motor 14, and the current detection circuit 12 is connected to the control chip 11 to detect the operating current of the stepping motor 14.
The control chip 11 is used for determining that the stepping motor and the driving chip work normally when the stepping motor is in a stop working state and the level signals output by the comparators are all low level signals. When 4 paths of driving IO input to the driving chip by the control chip are all low level, the stepping motor stops working, at the moment, the running current of the stepping motor is 0, the input voltage of the positive phase end of the comparator is 0, and the output end of each comparator continuously outputs a low level signal, which indicates that the stepping motor is in a stop working state, the stepping motor and the driving chip are not in fault, and the state is normal.
The control chip 11 is further configured to determine that the stepping motor or the driving chip is abnormal when the stepping motor is in a stop state and the level signal output by the comparator is a high level signal. If any comparator outputs a high level signal, which indicates that the current running current of the stepping motor is not 0, the stepping motor or the driving chip works abnormally, and a fault may exist.
When the stepping motor stops working, whether output level signals of the comparator are all low levels or not is judged, whether the stepping motor or the driving chip works abnormally or not can be accurately determined, and the accuracy of fault detection of the stepping motor is improved.
In a possible embodiment, the fault detection system includes a first comparator and a second comparator, the reference current of the first comparator is a first theoretical operating current of the stepping motor in a single-phase operating state, and the reference current of the second comparator is a second theoretical operating current of the stepping motor in a two-phase operating state; when the actual running current of the stepping motor is larger than the first theoretical running current in the single-phase working state, the output end of the first comparator is inverted from a low-level output signal to a high-level output signal; when the actual running current of the stepping motor is larger than the second theoretical running current in the two-phase working state, the output end of the second comparator is inverted from the low-level output signal to the high-level output signal.
The control chip is used for judging whether a first level signal output by the first comparator and a second level signal output by the second comparator are overturned when the stepping motor is in a single-phase working state, and if the first level signal is a high level signal and the second level signal is a low level signal, the stepping motor and the driving chip are determined to work normally; otherwise, determining that the stepping motor or the driving chip works abnormally.
When 4 drive IO of the control chip only outputs low level in 1 way, the stepping motor is in a single-phase working state, if the control chip detects that the first comparator outputs a high level signal and the second comparator outputs a low level signal, the result shows that the input current of the positive phase end of the comparator is larger than or equal to the first theoretical operating current and smaller than the second theoretical operating current, the stepping motor and the drive chip are not in fault, and the working state is normal. If the first comparator does not output a high level signal and the second comparator outputs a low level signal, it indicates that the running current of the stepping motor is abnormal, and it may be that the stepping motor or the driving chip has a fault and works abnormally.
The reference current for turning the output level signals of the first comparator and the second comparator is triggered to be respectively set as the theoretical operating current when the stepping motor normally operates in a single-phase working state and a two-phase working state, so that the control chip can effectively judge whether the stepping motor works abnormally or not in the single-phase working state according to the output level signals of the first comparator and the second comparator, and the influence on components driven by the stepping motor during working is avoided.
In a possible embodiment, the fault detection system further includes a third comparator, the reference current of the third comparator is a third operating current (such as 1.2 × second theoretical operating current — 1.5 × second theoretical operating current), and the third operating current is greater than the second theoretical operating current, that is, when the operating current of the stepping motor is greater than the third operating current, the output terminal of the third comparator generates a signal inversion output high level.
The control chip is used for judging whether the first level signal, the second level signal and the third level signal output by the third comparator are overturned when the stepping motor is in a two-phase working state, and if the first level signal and the second level signal are high level signals and the third level signal is a low level signal, the stepping motor and the driving chip are determined to work normally; otherwise, determining that the stepping motor or the driving chip works abnormally.
When two paths of the 4 paths of drive IO of the control chip output low level, the stepping motor is indicated to be in a two-phase working state, if the control chip detects that the first comparator and the second comparator both output high level signals and the third comparator outputs low level signals, the fact that the input current of the positive phase end of the comparator is larger than or equal to the second theoretical operating current and smaller than the third operating current is indicated, the stepping motor and the drive chip are not in fault, and the working state is normal. If the first comparator and the second comparator output high level signals and the third comparator outputs low level signals, it is indicated that the running current of the stepping motor is abnormal, and it may be that the stepping motor or the driving chip has a fault and works abnormally. If the third comparator outputs a high level signal, the running current of the stepping motor is larger, and the stepping motor or the driving chip works abnormally.
The reference current of the third comparator is set to be the third running current larger than the second theoretical running current, so that the control chip can effectively judge whether the stepping motor works abnormally under the two-phase working state according to the output level signals of the three comparators, and can also detect whether the stepping motor has abnormal large current, thereby avoiding the stepping motor from being burnt due to overlarge current and improving the working reliability and safety of the stepping motor.
In a possible embodiment, referring to the schematic structural diagram of the fault detection system shown in fig. 2, the fault detection system further includes: and the voltage detection circuit 21 is used for detecting the working voltage of the stepping motor and transmitting the working voltage to the control chip by the voltage detection circuit 21.
The control chip 11 is further configured to obtain a working voltage of the stepping motor in a normal operation state, and determine and output a first theoretical operating current and a second theoretical operating current based on the working voltage and a dc resistance of each phase of the stepping motor.
Under the condition that the stepping motor and the driving chip are determined to normally operate without faults, the working voltage Vcc of the stepping motor is detected based on the voltage detection circuit, the working current Ia = Ib = Ic = Id = Vcc/Rx of each phase is calculated according to the working voltage Vcc and the direct-current resistance Rx of each phase of the stepping motor, the theoretical operating current when the stepping motor is in a single-phase working state is the first theoretical operating current Vcc/Rx, and the theoretical operating current when the stepping motor is in a two-phase working state is the second theoretical operating current 2 Vcc/Rx. The reference current of the first comparator is Vcc/Rx, and when the current detection circuit detects that the running current of the stepping motor is greater than or equal to the first theoretical running current Vcc/Rx, a high-level signal is output; the reference current of the second comparator is 2 × Vcc/Rx, and when the current detection circuit detects that the running current of the stepping motor is more than or equal to the second theoretical running current 2 × Vcc/Rx, a high level signal is output.
In a specific embodiment, the reference current of the third comparator and the third operating current may be 2.5 x vcc/Rx. By detecting the working voltage of the stepping motor in the normal running state and calculating the reference currents of the first comparator and the second comparator according to the working voltage and the direct current resistance of each phase, the selection of components of the reference circuit at the negative phase end of the comparator and the model of the comparator can be assisted, so that the current condition of the stepping motor can be fed back quickly and accurately by the comparator, and the fault detection effectiveness of the fault detection system is ensured.
In a possible embodiment, as shown in fig. 2, the fault detection system further includes a fault notification device 22, where the fault notification device 22 is connected to the control chip 11, and the control chip 11 is configured to control the fault notification device to send a fault notification when the stepper motor works abnormally. The fault indication may comprise any one or more of a sound indication, a light indication and a display indication. Through sending out the fault suggestion when confirming that step motor or driver chip work is unusual to remind the user in time to carry out troubleshooting, avoid arousing step motor place equipment work unusual, promoted user experience.
The above fault detection system provided by this embodiment realizes current detection of the stepping motor in different working states, can quickly and accurately detect whether the stepping motor or the driving chip thereof is in abnormal working or not in different working states, and can give an alarm in time when the stepping motor or the driving chip thereof is in abnormal working, thereby avoiding causing abnormal operation of the device.
Corresponding to the fault detection system provided in the above embodiment, an embodiment of the present invention provides a fault detection method, which can be applied to the above fault detection system, and refer to a flow chart of the fault detection method shown in fig. 3, where the method mainly includes the following steps:
step S302: when the control chip outputs a driving signal to the stepping motor, the working state of the stepping motor is determined according to the driving signal.
The working states of the stepping motor include a single-phase working state and a two-phase working state. The step motor can be a motor for driving an electronic expansion valve in an air conditioner, and when the air conditioner adjusts the opening of the electronic expansion valve, the fault detection method is automatically executed to carry out fault self-detection on the step motor.
Step S304: and acquiring level signals output by the comparators.
The reference currents of the comparators are different, and the reference currents of the comparators are related to theoretical operating currents of the stepping motor in different working states.
Step S306: and judging whether the stepping motor works abnormally or not based on the working state and each level signal.
Whether the electronic expansion valve has a fault is judged by detecting the current of a stepping motor driving the electronic expansion valve.
According to the fault detection method provided by the embodiment, the working state of the stepping motor is determined, the collected running current of the stepping motor is input into the comparator, so that the comparator outputs different level signals according to different running currents, whether the stepping motor has a fault or not can be accurately judged according to the working state of the stepping motor and the level signals fed back by the comparator, fault self-detection on the stepping motor is realized, the influence on the motion angle of a part driven by the stepping motor is avoided, and the influence on the normal operation of equipment where the stepping motor is located is further avoided.
In a possible implementation manner, the present embodiment provides an implementation manner for determining whether the stepping motor operates abnormally based on the operating state and the level signals, and the following steps (1) to (3) may be specifically referred to:
step (1): when the stepping motor is in a stop working state and the level signals output by the comparators are all low level signals, determining that the stepping motor or the driving chip works normally; and when the stepping motor is in a stop working state and the level signal output by the comparator is a high level signal, determining that the stepping motor or the driving chip works abnormally.
Step (2): when the stepping motor is in a single-phase working state, if a first level signal output by the first comparator is a high level signal and a second level signal output by the second comparator and a third level signal output by the third comparator are both low level signals, determining that the stepping motor and the driving chip work normally; otherwise, determining that the stepping motor or the driving chip works abnormally.
And (3): when the stepping motor is in a two-phase working state, if the first level signal and the second level signal are both high level signals and the third level signal is a low level signal, determining that the stepping motor and the driving chip work normally; otherwise, determining that the stepping motor or the driving chip works abnormally.
In a possible implementation manner, the fault detection method provided in this embodiment further includes: the method comprises the steps of obtaining working voltage of the stepping motor in a normal operation state, and determining first theoretical operation current and second theoretical operation current based on the working voltage and direct current resistance of each phase of the stepping motor.
And controlling the fault prompting equipment to send out fault prompts when the stepping motor or the driving chip works abnormally.
The fault detection method provided by the embodiment realizes current detection of the stepping motor in different working states, can quickly and accurately detect whether the stepping motor or the driving chip thereof is abnormally operated and has a fault or not in different working states, and can give an alarm in time when the stepping motor or the driving chip thereof is abnormally operated so as to avoid causing abnormal operation of equipment.
Corresponding to the fault detection system provided in the above embodiment, an embodiment of the present invention provides an example of performing fault detection on an electronic expansion valve of an air conditioner by using the above fault detection system, which may be specifically executed with reference to the following steps 1 to 4:
step 1, obtaining 4 paths of drive IO level signals output to a stepping motor drive chip by a singlechip.
The fault detection system comprises a single chip microcomputer, a stepping motor driving chip, a voltage detection voltage, a current detection circuit, a first comparator, a second comparator, a third comparator and a fault indicator lamp.
When the running current of the stepping motor detected by the current detection circuit is more than or equal to single-phase working current Vcc/Rx, the output level of the first comparator is inverted from a low level signal to a high level signal; when the running current of the stepping motor detected by the current detection circuit is greater than or equal to two-phase working current 2 x Vcc/Rx, the output level of the second comparator is inverted from a low level signal to a high level signal; when the running current of the stepping motor detected by the current detection circuit is more than or equal to 2.5 times of single-phase working current 2.5 x Vcc/Rx, the output level of the third comparator is inverted from a low level signal to a high level signal. When the stepping motor works, when the first comparator outputs a high level, and the second comparator and the third comparator output a low level, the stepping motor works in a single-phase state; when the first comparator and the second comparator output high level and the third comparator output low level, the stepping motor works in a two-phase state; the output low level of the third comparator represents that the stepping motor has abnormal large current and the circuit is in failure.
And step 2, when the 4 paths of drive IO of the singlechip microcomputer all output low levels, the stepping motor does not work, and the working current is 0. The current detection circuit detects the current of the driving chip (namely the running current of the stepping motor), and at the moment, if the first comparator, the second comparator and the third comparator are not turned over (namely, low level signals are all output), the stepping motor does not work and is in a normal state; and otherwise, if the comparator is turned over, the step motor or the driving chip circuit is abnormal, and the fault indicator lamp is controlled to be on.
And step 3, when 4 paths of drive IO of the single chip microcomputer are only 1 path of output low level, the stepping motor is in a single-phase working state. The current detection circuit detects the current of the driving chip (namely the running current of the stepping motor), and at the moment, if the first comparator is turned over (namely, a high level signal is output), and the second comparator and the third comparator are not turned over (namely, a low level signal is output), the stepping motor works normally; otherwise, the step motor or the driving chip circuit is abnormal, and the fault indicator lamp is controlled to be on.
And step 4, when the singlechip drives the IO two paths to output low level, the stepping motor is in a two-phase working state. The current detection circuit detects the current of the driving chip (namely the running current of the stepping motor), and at the moment, if the first comparator and the second comparator are turned over (namely high level signals are output) and the third comparator is not turned over (namely low level signals are output), the stepping motor works normally; otherwise, the step motor or the driving circuit is abnormal, and the fault indicator lamp is controlled to be on.
Corresponding to the fault detection system provided by the above embodiment, this embodiment provides an air conditioner, which includes the fault detection system provided by the above embodiment, and the fault detection system is configured to detect whether a stepping motor driving an electronic expansion valve or an air guide door is abnormal, so as to determine whether the electronic expansion valve or the air guide door has a fault, and when the stepping motor is abnormal, determine that the electronic expansion valve or the air guide door has a fault.
The present embodiment further provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the computer program implements the processes of the foregoing fault detection method embodiment, and can achieve the same technical effects, and in order to avoid repetition, details are not repeated here. The computer-readable storage medium may be a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk.
Of course, those skilled in the art will understand that all or part of the processes in the methods of the above embodiments may be implemented by instructing the control device to perform operations through a computer, and the programs may be stored in a computer-readable storage medium, and when executed, the programs may include the processes of the above method embodiments, where the storage medium may be a memory, a magnetic disk, an optical disk, and the like.
Although the present invention is disclosed above, the present invention is not limited thereto. Various changes and modifications may be effected by one skilled in the art without departing from the spirit and scope of the invention, as defined in the appended claims.
Finally, it should also be noted that, in this document, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrases "comprising a," "8230," "8230," or "comprising" does not exclude the presence of additional like elements in a process, method, article, or apparatus that comprises the element.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Although the present invention is disclosed above, the present invention is not limited thereto. Various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (10)
1. A fault detection system, comprising: the control chip, the current detection circuit and the plurality of comparators are arranged on the circuit board; the output end of the current detection circuit is connected with the input end of each comparator, and the output end of each comparator is connected with the control chip;
the control chip is used for outputting a driving signal to the stepping motor and determining the working state of the stepping motor according to the driving signal; wherein the working state comprises a single-phase working state and a two-phase working state;
the current detection circuit is used for detecting the running current of the stepping motor and inputting the running current of the stepping motor into each comparator;
the comparator is used for outputting a corresponding level signal according to the magnitude relation between the running current and the corresponding reference current; the reference current of each comparator is different, and is related to the theoretical operating current of the stepping motor in different working states;
the control chip is further used for obtaining level signals output by the comparators and judging whether the stepping motor works abnormally or not based on the working state and the level signals.
2. The fault detection system of claim 1, comprising: the driving chip is arranged between the control chip and the stepping motor, and the current detection circuit is connected with the control chip so as to detect the operating current of the stepping motor;
the control chip is used for determining that the stepping motor and the driving chip work normally when the stepping motor is in a stop working state and the level signals output by the comparators are all low level signals;
the control chip is also used for determining that the stepping motor or the driving chip works abnormally when the stepping motor is in a stop working state and the level signal output by the comparator is a high level signal.
3. The fault detection system of claim 2, comprising: the reference current of the first comparator is a first theoretical operating current of the stepping motor in a single-phase working state, and the reference current of the second comparator is a second theoretical operating current of the stepping motor in a two-phase working state;
the control chip is used for judging whether a first level signal output by the first comparator and a second level signal output by the second comparator are overturned when the stepping motor is in the single-phase working state, and if the first level signal is a high level signal and the second level signal is a low level signal, determining that the stepping motor and the driving chip work normally; otherwise, determining that the stepping motor or the driving chip works abnormally.
4. The fault detection system of claim 3, further comprising: a third comparator, a reference current of which is a third operating current, the third operating current being greater than the second theoretical operating current;
the control chip is used for judging whether the first level signal, the second level signal and a third level signal output by the third comparator are overturned when the stepping motor is in the two-phase working state, and if the first level signal and the second level signal are high level signals and the third level signal is a low level signal, the stepping motor and the driving chip are determined to work normally; otherwise, determining that the stepping motor or the driving chip works abnormally.
5. The fault detection system of claim 3, comprising: the voltage detection circuit is used for detecting the working voltage of the stepping motor and transmitting the working voltage to the control chip;
the control chip is used for obtaining working voltage of the stepping motor in a normal operation state and determining the first theoretical operation current and the second theoretical operation current based on the working voltage and the direct current resistance of each phase of the stepping motor.
6. The fault detection system according to any one of claims 1 to 5, comprising: the fault prompting device is connected with the control chip;
the control chip is used for controlling the fault prompting equipment to send out fault prompts when the stepping motor works abnormally.
7. A fault detection method, characterized by being applied to the fault detection system of any one of claims 1-6; the fault detection method comprises the following steps:
when the control chip outputs a driving signal to the stepping motor, determining the working state of the stepping motor according to the driving signal; wherein the working state comprises a single-phase working state and a two-phase working state;
acquiring level signals output by each comparator; the reference current of each comparator is different, and the reference current of each comparator is related to the theoretical running current of the stepping motor in different working states;
and judging whether the stepping motor works abnormally or not based on the working state and each level signal.
8. The method according to claim 7, wherein the fault detection system includes a driver chip disposed between the control chip and the stepping motor, and the step of determining whether the stepping motor is operating abnormally based on the operating state and each of the level signals includes:
when the stepping motor is in a stop working state and the level signals output by the comparators are all low level signals, determining that the stepping motor or the driving chip works normally;
and when the stepping motor is in a stop working state and the level signal output by the comparator is a high level signal, determining that the stepping motor or the driving chip works abnormally.
9. The fault detection method according to claim 8, wherein the fault detection system includes a first comparator, a second comparator and a third comparator, the reference current of the first comparator is a first theoretical operating current of the stepping motor in a single-phase operating state, the reference current of the second comparator is a second theoretical operating current of the stepping motor in a two-phase operating state, the reference current of the third comparator is a third operating current, and the third operating current is greater than the second theoretical operating current;
the step of judging whether the stepping motor works abnormally based on the working state and each level signal comprises the following steps:
when the stepping motor is in the single-phase working state, if the first level signal output by the first comparator is a high level signal and the second level signal output by the second comparator and the third level signal output by the third comparator are both low level signals, determining that the stepping motor and the driving chip work normally; otherwise, determining that the stepping motor or the driving chip works abnormally;
when the stepping motor is in the two-phase working state, if the first level signal and the second level signal are both high level signals and the third level signal is a low level signal, determining that the stepping motor and the driving chip work normally; otherwise, determining that the stepping motor or the driving chip works abnormally.
10. An air conditioner comprising the fault detection system as claimed in any one of claims 1 to 6, wherein the fault detection system is adapted to detect whether a stepping motor for driving an electronic expansion valve or an air guide door is abnormally operated.
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Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102891644A (en) * | 2012-10-08 | 2013-01-23 | 宁波大学 | Two-phase stepping motor driving circuit and motor fault detection method |
| CN104022697A (en) * | 2014-06-13 | 2014-09-03 | 四川亚美动力技术有限公司 | Constant current source driving module for stepping motor of engine |
| JP2015061341A (en) * | 2013-09-17 | 2015-03-30 | Ｎｅｃエンジニアリング株式会社 | Stepping motor failure detection circuit, stepping motor drive unit, and stepping motor drive system |
| CN204287304U (en) * | 2014-10-16 | 2015-04-22 | 常州品博驱动科技有限公司 | The testing circuit of one kind of multiple voltage failure patterns |
| CN105510827A (en) * | 2015-12-04 | 2016-04-20 | 珠海格力电器股份有限公司 | Method and device for monitoring working state of stepping motor and air conditioner controller |
| CN206004565U (en) * | 2016-08-31 | 2017-03-08 | 弘乐电气有限公司 | Servo-type voltage regulator controller |
| CN107340472A (en) * | 2017-06-30 | 2017-11-10 | 杭州华橙网络科技有限公司 | A kind of detection means and method of stepper motor motion state |
| KR20180038723A (en) * | 2016-10-07 | 2018-04-17 | 주식회사 만도 | Apparatus and method for detecting failure of motor system |
| CN208797564U (en) * | 2018-10-08 | 2019-04-26 | 岩金龙 | Stepper motor protective device |
| CN110460293A (en) * | 2019-08-23 | 2019-11-15 | 杭州宝协机电有限公司 | A kind of servo control system and its control method with monitoring function |
| CN209656857U (en) * | 2018-12-28 | 2019-11-19 | 一诺云科技(武汉)有限公司 | A kind of stepper motor detection case |
| CN213240402U (en) * | 2020-10-09 | 2021-05-18 | 深圳莱福德科技股份有限公司 | Load state detection circuit and system |
-
2021
- 2021-12-28 CN CN202111628180.4A patent/CN114279055B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102891644A (en) * | 2012-10-08 | 2013-01-23 | 宁波大学 | Two-phase stepping motor driving circuit and motor fault detection method |
| JP2015061341A (en) * | 2013-09-17 | 2015-03-30 | Ｎｅｃエンジニアリング株式会社 | Stepping motor failure detection circuit, stepping motor drive unit, and stepping motor drive system |
| CN104022697A (en) * | 2014-06-13 | 2014-09-03 | 四川亚美动力技术有限公司 | Constant current source driving module for stepping motor of engine |
| CN204287304U (en) * | 2014-10-16 | 2015-04-22 | 常州品博驱动科技有限公司 | The testing circuit of one kind of multiple voltage failure patterns |
| CN105510827A (en) * | 2015-12-04 | 2016-04-20 | 珠海格力电器股份有限公司 | Method and device for monitoring working state of stepping motor and air conditioner controller |
| CN206004565U (en) * | 2016-08-31 | 2017-03-08 | 弘乐电气有限公司 | Servo-type voltage regulator controller |
| KR20180038723A (en) * | 2016-10-07 | 2018-04-17 | 주식회사 만도 | Apparatus and method for detecting failure of motor system |
| CN107340472A (en) * | 2017-06-30 | 2017-11-10 | 杭州华橙网络科技有限公司 | A kind of detection means and method of stepper motor motion state |
| CN208797564U (en) * | 2018-10-08 | 2019-04-26 | 岩金龙 | Stepper motor protective device |
| CN209656857U (en) * | 2018-12-28 | 2019-11-19 | 一诺云科技(武汉)有限公司 | A kind of stepper motor detection case |
| CN110460293A (en) * | 2019-08-23 | 2019-11-15 | 杭州宝协机电有限公司 | A kind of servo control system and its control method with monitoring function |
| CN213240402U (en) * | 2020-10-09 | 2021-05-18 | 深圳莱福德科技股份有限公司 | Load state detection circuit and system |
Non-Patent Citations (1)
| Title |
|---|
| 韩彩霞.单片机原理及应用.华中科技大学出版社,2022,第163-164页. * |
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