CN109406989B - Load loop detection method, load detection circuit and electronic equipment - Google Patents

Abstract

The present invention belongs to the field of load detection technology, and in particular, relates to a load loop detection method, a load detection circuit, and an electronic device. By sending a drive signal to the thyristor, the load current sampled by the load detection circuit and the level signal converted from the load current are obtained, the load current includes a first current sampled to flow through the load or a second current that does not flow through the load but flows through the load detection circuit, the second current is less than the holding current of the thyristor, and then the working state of the thyristor or the load is determined according to the drive signal and the level signal. Therefore, the detection of the state of the load and the thyristor can be realized, and the overall safety performance is improved.

Description

A load circuit detection method, load detection circuit and electronic equipment

Technical Field

The present invention relates to the technical field of load detection, and in particular to a load loop detection method, a load detection circuit and an electronic device.

Background technique

At present, load control is the ultimate goal of various electronic intelligent control products. Among them, the thyristor is used as a switch, and the load is connected in series with the thyristor and connected to the power supply to achieve control of the load.

In the process of implementing the present invention, the inventors found that the prior art has at least the following problems:

When a load circuit fails, the power supply continues to provide power, but the status of the load or thyristor cannot be confirmed, posing a great threat to safety.

Summary of the invention

The present invention aims to solve the problem that when the load is open or the thyristor fails, the state of the load or thyristor cannot be confirmed, which causes potential safety hazards in the traditional load circuit detection method, and provides a load circuit detection method. The technical solution is as follows:

To solve the above technical problems, the embodiments of the present invention provide the following technical solutions:

In a first aspect, an embodiment of the present invention provides a load circuit detection method, which is applied to a load detection circuit, wherein the load detection circuit is used to detect a working state of a load circuit, wherein the load circuit includes a thyristor and a load, wherein the thyristor is connected to the load, and wherein the method includes:

Sending a driving signal to the thyristor, wherein the driving signal is used to instruct the thyristor to operate in an on state or an off state;

Acquire a load current sampled by the load detection circuit and a level signal converted from the load current, wherein the load current includes a first current sampled to flow through the load or a second current sampled to flow through the load detection circuit without flowing through the load, wherein the second current is less than a holding current of the thyristor;

The working state of the thyristor or the load is determined according to the driving signal and the level signal.

Further, determining the working state of the thyristor according to the driving signal and the level signal includes:

When the driving signal is used to instruct the thyristor to operate in a cut-off state, the operating state of the thyristor is determined according to the level type of the level signal.

Further, determining the working state of the thyristor according to the level type of the level signal includes:

When the level signal is a periodic high and low level, the thyristor is in a normal state;

When the level signal is at a continuous low level, the thyristor is in a breakdown state or a short circuit state.

Further, when the thyristor is in a normal state, determining the working state of the load according to the drive signal and the level signal includes:

When the driving signal is used to indicate that the thyristor is operating in a conducting state, and the level signal is a periodic high and low level, the load is in a fault state;

When the driving signal is used to indicate that the thyristor is operating in the on state, and the level signal is a continuous low level, the load is in a normal state.

Furthermore, before sending the driving signal to the thyristor, the method includes:

Obtain the zero-crossing signal of the power supply;

The time for sending the driving signal of the thyristor is set according to the zero-crossing signal.

In a second aspect, an embodiment of the present invention provides a load detection circuit for detecting a working state of a load circuit, wherein the load circuit includes a thyristor and a load, wherein the thyristor is connected to the load, and the load detection circuit includes:

A sampling module, the sampling module is connected to the load, and is used to sample a load current and convert the load current into a level signal, wherein the load current includes sampling a first current flowing through the load or a second current flowing through the load detection circuit without flowing through the load, and the second current is less than a holding current of the thyristor;

A control module, the control module is connected to the sampling module and the thyristor;

Wherein, the control module comprises:

at least one processor; and

A memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor so that the at least one processor can be used to execute the load loop detection method as described above.

Further, the sampling module includes: a sampling point circuit connected in parallel with the load, and a shaping circuit connected to the sampling circuit and the control module;

The sampling circuit is used to obtain the load current sampled by the load detection circuit;

The shaping circuit is used for converting the load current into a level signal.

Furthermore, the sampling circuit includes: a first resistor, one end of the first resistor is connected to the other end of the load and connected to a power supply, and the other end of the first resistor is connected to one end of the load.

Further, the shaping circuit includes: a second resistor, a first diode, a second diode and a first capacitor;

One end of the second resistor is connected to one end of the load, the other end of the second resistor is connected to the cathode of the first diode and the anode of the second diode, the anode of the first diode is grounded, the cathode of the second diode is connected to a forward voltage, one end of the first capacitor is connected to the control module and the other end of the second resistor, and the other end of the first capacitor is grounded.

Furthermore, the load detection circuit further includes:

A protection circuit is connected between the control end of the thyristor and the control module to prevent the driving voltage from damaging the thyristor.

The protection circuit includes a third resistor and a second capacitor, one end of the second capacitor is connected to the other end of the third resistor, the other end of the second capacitor is connected to the control end of the thyristor, and one end of the third resistor is connected to the control module.

Furthermore, the load detection circuit further includes:

A RC step-down circuit, which is connected to the other end of the load and is used to step down, stabilize and filter the power signal;

The RC step-down circuit includes a fourth resistor, a third capacitor, a fifth diode, a voltage-stabilizing diode and an electrolytic capacitor; one end of the fourth resistor is connected to the power input terminal, and the other end is connected to one end of the third capacitor, the other end of the third capacitor is connected to the negative electrode of the voltage-stabilizing diode and the positive electrode of the fifth diode, the positive electrode of the voltage-stabilizing diode is grounded, the negative electrode of the fifth diode is connected to the positive electrode of the electrolytic capacitor, the positive electrode of the electrolytic capacitor is connected to a forward voltage, and the negative electrode of the electrolytic capacitor is grounded.

Furthermore, the load detection circuit further includes:

A zero-crossing detection circuit, the zero-crossing detection circuit is connected to the other end of the load and the control module, and is used to perform zero-crossing detection on the power supply signal and send the acquired zero-crossing signal to the processing module;

The zero-crossing detection circuit includes a third resistor, a third diode and a fourth diode; one end of the third resistor is connected to the power input end, the other end of the third resistor is connected to the cathode of the third diode and the anode of the fourth diode, the anode of the third diode is grounded, the anode of the fourth diode is connected to the control module, and the cathode of the fourth diode is connected to the forward voltage.

In a third aspect, an embodiment of the present invention provides an electronic device, including:

housing; and,

As the aforementioned load detection circuit, the load detection circuit is arranged in the housing.

The beneficial effect of the embodiment of the present invention is that: the load circuit detection method, load detection circuit and electronic device provided by the embodiment, by sending a drive signal to the thyristor, obtains the load current sampled by the load detection circuit and the level signal converted from the load current, the load current includes a first current sampled to flow through the load or a second current that does not flow through the load but flows through the load detection circuit, the second current is less than the holding current of the thyristor, and then determines the working state of the thyristor or the load according to the drive signal and the level signal. Therefore, the detection of the state of the load and the thyristor can be realized, and the overall safety performance is improved.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of an application scenario of load detection provided by an embodiment of the present invention;

FIG2 is a schematic flow chart of a load circuit detection method provided in accordance with an embodiment of the present invention;

3 is a schematic diagram of the structure of a load detection circuit provided by an embodiment of the present invention;

FIG4 is a schematic diagram of the structure of another load detection circuit provided by an embodiment of the present invention;

5 is a schematic diagram of the structure of another load detection circuit provided by an embodiment of the present invention;

6 is a schematic diagram of the structure of another load detection circuit provided by an embodiment of the present invention;

Detailed ways

In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

It should be noted that, if there is no conflict, the various features in the embodiments of the present invention can be combined with each other, all within the scope of protection of the present invention. In addition, although the functional modules are divided in the device schematic diagram and the logical order is shown in the flow chart, in some cases, the steps shown or described can be performed in a different order from the module division in the device or the flow chart. Furthermore, the words "first", "second", "third", etc. used in the present invention do not limit the data and execution order, but only distinguish the same items or similar items with basically the same functions and effects.

When realizing intelligent product control, it is an essential and important link to control the load by turning on or off the switch components. For example, many home appliance control boards currently use the on and off of thyristors to control the load. However, since both the load and the thyristor are electronic components, there is a risk of failure and loss of control. Once these key components fail or lose control, they may cause significant property losses or casualties. Therefore, it is necessary to set a load detection circuit for the load circuit to monitor the load and thyristor.

Generally, the load detection circuit is usually equipped with a sampling module to obtain the current signal in the load circuit, and convert the detection value into a voltage signal, and then judge the state of the load and switch components in the load circuit according to the signal input into the load circuit and the voltage signal obtained by the load detection circuit. A single-chip microcomputer is usually used in the load detection circuit to obtain the voltage signal. In addition, the technical solutions recorded by the existing technology center generally connect the sampling module in series to the load circuit to facilitate the acquisition of the current in the load circuit. However, when the load is open or the thyristor fails, this detection method is in a suspended state, and the specific state of the load and the thyristor is unknown. In addition, the power supply continues to provide power to the load, which poses certain safety hazards.

Based on this, an embodiment of the present invention provides a load loop detection method, a load detection circuit and an electronic device.

The load circuit detection method applied to the load detection circuit provided in the embodiment of the present invention is a load circuit detection method capable of improving the safety performance of the load circuit, specifically comprising: sending a drive signal to the thyristor, the drive signal being used to indicate that the thyristor is operating in an on state or an off state;

Acquire a load current sampled by the load detection circuit and a level signal converted from the load current, wherein the load current includes a first current sampled to flow through the load or a second current sampled to flow through the load detection circuit without flowing through the load, wherein the second current is less than a holding current of the thyristor;

The working state of the thyristor or the load is determined according to the driving signal and the level signal.

Among them, in the embodiment of the present invention, by sending a driving signal to the thyristor, the load current sampled by the load detection circuit and the level signal converted from the load current are obtained, the load current includes a first current sampled flowing through the load or a second current that does not flow through the load but flows through the load detection circuit, the second current is less than the holding current of the thyristor, and then the working state of the thyristor or the load is determined according to the driving signal and the level signal. Therefore, it is ensured that the load detection circuit will not be in a suspended state, so that the state of the load and the thyristor can be provided in real time, improving the overall safety performance.

Among them, the load detection circuit for detecting the working status of the load circuit provided in the embodiment of the present invention is a virtual device composed of a software program that can implement the load circuit detection method applied to the load detection circuit provided in the embodiment of the present invention. It is based on the same inventive concept as the load circuit detection method applied to the load detection circuit provided in the embodiment of the present invention, and has the same technical features and beneficial effects.

The electronic device provided by the embodiment of the present invention is capable of executing the load loop detection method provided by the embodiment of the present invention, or running the load detection circuit provided by the embodiment of the present invention.

Specifically, the embodiments of the present invention are further described below in conjunction with the accompanying drawings.

FIG1 is a schematic diagram of an application scenario of load detection provided by conventional technology, wherein the application environment includes: a power supply, a load, a thyristor and a load detection module.

Among them, the power supply, load and thyristor form a conduction loop, the thyristor realizes the switch function, and the control end of the thyristor also includes access to the drive signal, and realizes the on or off working state according to the drive signal, so as to realize the control of the load by its own shutdown and conduction. The load detection module is usually composed of a sampling module and a detection module. The sampling module is generally a resistor, inductor and other components that can realize the voltage division effect. The detection module is usually a single-chip microcomputer, which acquires the signal of the sampling module and judges the working state of the thyristor and the load according to the signal acquired by the detection module and the signal input by the conduction loop.

It should be noted that the positioning method provided in the embodiment of the present invention can be further extended to other suitable application environments, and is not limited to the application environment shown in Figure 1. In actual application, the application environment can also include more targets.

FIG. 2 is a flow chart of a load circuit detection method provided by an embodiment of the present invention. Specifically, referring to FIG. 2 , the method may include:

S10: Sending a driving signal to the thyristor, wherein the driving signal is used to instruct the thyristor to operate in an on state or an off state;

In this embodiment, the driving signal is generated by a controller for realizing the control function, and is sent to the control end of the thyristor to control the conduction or shutoff of the thyristor. The driving signal usually includes a high level or a low level. For example, when the thyristor is in a normal working state, when the driving signal is a high level, the thyristor is in a conducting state, and when the driving signal is a low level, the thyristor is in a cut-off state; the driving signal is used to indicate that the thyristor is working in a conducting state or a cut-off state, that is, the driving signal includes a conducting signal or a cut-off signal. The conducting signal means that when the thyristor is in a normal working state, the thyristor is driven to be in a conducting state, and the cut-off signal means that when the thyristor is in a normal working state, the thyristor is driven to be in a cut-off state. Generally, the conducting signal is one of the high level and the low level, and the cut-off signal is the other. It should be noted that the sending of a drive signal to the thyristor, wherein the drive signal is used to indicate whether the thyristor is operating in an on state or an off state, is performed without determining the state of the thyristor and the load. That is to say, the drive signal at this time will definitely make the thyristor be in the working state corresponding to the drive signal; for example, the drive signal at this time is a signal indicating that the thyristor is operating in an off state, while the thyristor is in an abnormal working state of "short circuit state". At this time, the thyristor will not operate in the off working state according to the drive signal, but will still be in a short circuit state.

S20: Acquire a load current sampled by the load detection circuit and a level signal converted from the load current, wherein the load current includes a first current sampled to flow through the load or a second current sampled to flow through the load detection circuit without flowing through the load, wherein the second current is less than a holding current of the thyristor;

In this embodiment, the load current includes a first current and a second current, the first current is the current obtained after the power source flows through the load, and the second current is the current obtained after the power source flows directly through the load detection circuit without flowing through the load. It should be noted that a module in the load detection circuit of this embodiment is connected in parallel with the load. When the load fails and cannot form a conductive loop through the load, the power source will flow directly through the module, thereby obtaining a second current of a different type from the first current obtained after flowing through the load. Furthermore, the overall resistance of the module is much higher than the resistance of the load, so that when the load is normal, the resistance value of the module has a negligible effect on the overall current of the load loop (because the module is connected in parallel with the load).

Furthermore, the second current is less than the holding current of the thyristor. It should be noted that the so-called holding current of the thyristor is the minimum current that keeps the thyristor forwardly conducting. When the current flowing through the thyristor is less than the holding current, the thyristor will automatically turn off even if the thyristor triggering conduction condition is met. In other words, when the load cannot form a conducting circuit with the load loop, the current after the power supply flows through the load detection circuit is not enough to reach the holding current of the thyristor, and even if the driving signal of the thyristor indicates that the thyristor is working in the conducting state, the thyristor will be turned off and then in the cut-off state. On the one hand, it plays a role in protecting the thyristor, and on the other hand, it uses this characteristic of the thyristor to achieve a high degree of recognition of the detection of the load. Even if the load is in an open circuit state, the detection circuit can obtain the specific working state of the load or the thyristor, thereby improving the overall safety performance.

S30: Determine the working state of the thyristor or the load according to the driving signal and the level signal.

In this embodiment, the working state of the thyristor or the load is determined according to the driving signal and the level signal, specifically as follows:

When the driving signal indicates that the thyristor is operating in the on state, and the level signal is a periodic high and low level, the thyristor is in a normal working state and the load is in an open circuit state;

When the driving signal indicates that the thyristor is operating in the on state, and the level signal is a continuous low level, the thyristor is in a short circuit or breakdown state and the load is in an uncertain state, or the thyristor is in a normal working state and the load is in a normal working state;

When the driving signal indicates that the thyristor is working in the cut-off state, and the level signal is a periodic high and low level, the thyristor is in a normal working state and the load is in an uncertain state;

When the driving signal indicates that the thyristor is operating in a cut-off state, and the level signal is a continuous low level, the thyristor is in a short-circuit or breakdown state and the load is in an uncertain state;

It should be noted that the uncertain state of the load means that the load can be in a normal working state or an open circuit state. When the thyristor can be in a normal state or a short circuit or breakdown state, it is necessary to first determine the working state of the thyristor; when the thyristor is in a short circuit or breakdown state, the thyristor should be repaired or replaced first. After the thyristor reaches a normal working state, you can choose to further detect the working state of the load; when the thyristor is in a normal working state, you can directly further detect the working state of the load.

For example, when it is detected that the driving signal indicates that the thyristor is working in the on state and the level signal is a continuous low level, there are two states of the load and the thyristor:

1. The thyristor is in a short circuit or breakdown state, and the load is in an uncertain state, that is, the load can be in a normal state or an open circuit state;

2. The thyristor is in normal working state and the load is in normal working state;

When this situation is detected, since the state of the thyristor is uncertain, it is necessary to further determine the working state of the thyristor. When the working state of the thyristor is detected to be a normal working state, the detection result of the load circuit corresponds to the second situation. When the working state of the thyristor is detected to be a short circuit or breakdown state, the detection result of the load circuit corresponds to the first situation.

In this embodiment, the working states of the load and the thyristor are detected by acquiring the driving signal of the input load circuit and the level signal acquired by the load detection circuit, thereby ensuring the safety of the load circuit and avoiding potential safety hazards.

Further, determining the working state of the thyristor or the load according to the drive signal and the level signal includes determining the working state of the thyristor according to the drive signal and the level signal;

Specifically, the control of the drive signal indicates that the thyristor is working in the cut-off state, and determines the state of the thyristor. When the thyristor is in the short-circuit state or the breakdown state, further maintenance is required by maintenance personnel. When the thyristor is in a good state, the drive signal can be controlled to indicate that the thyristor is working in the on state, and the working state of the load is further judged.

Specifically, determining the working state of the thyristor according to the driving signal and the level signal includes:

When the driving signal is used to instruct the thyristor to operate in a cut-off state, the operating state of the thyristor is determined according to the level type of the level signal.

It should be noted that when the thyristor is in a normal working state, the driving signal is used to indicate that the thyristor is working in a cut-off state, and the level signals obtained by the load detection circuit are all periodic high and low levels, that is, the power signal does not pass through the thyristor to be grounded, but flows directly through the load detection circuit. At this time, because a part of the load detection circuit is connected in parallel with the load, even if the load is in an uncertain working state, it does not affect the periodic high and low level signals obtained by the load detection circuit. Based on this characteristic, the working state of the thyristor can be determined. Prioritizing the state of the thyristor can provide a reference basis for the subsequent working state of the load, thereby realizing accurate detection of the load and thyristor in the load circuit, eliminating the safety hazards caused by the unclear state of the thyristor.

Specifically, determining the working state of the thyristor according to the level type of the level signal includes:

When the level signal is a periodic high and low level, the thyristor is in a normal state;

When the level signal is at a continuous low level, the thyristor is in a breakdown state or a short circuit state.

When the thyristor is detected to be in a breakdown state or a short circuit state, the detection system will automatically generate an alarm message and notify the user or manager by text or voice to switch the thyristor circuit or repair or replace the thyristor. Accurate detection of the working state of the thyristor eliminates the potential safety hazards of the load circuit caused by unclear thyristor state and improves the overall safety performance.

Furthermore, when it is ensured that the working state of the thyristor is in a normal working state, the working state of the load can be further detected. Under the premise that the thyristor is in a normal working state and the driving signal is used to indicate that the thyristor is working in a conducting state, the working state of the load is detected at this time, and the working state of the load can also be further accurately detected, that is, it can be accurately detected whether the load is in a normal working state or an open circuit state.

Specifically, when the thyristor is in a normal state, determining the working state of the load according to the drive signal and the level signal includes:

When the driving signal is used to indicate that the thyristor is operating in a conducting state, and the level signal is a periodic high and low level, the load is in an open circuit state;

When the driving signal is used to indicate that the thyristor is operating in the on state, and the level signal is a continuous low level, the load is in a normal state.

Among them, after confirming the working status of the thyristor, the working status of the load is confirmed, which realizes the detection of the status of two key components in the load circuit, solves the hidden safety hazard problem to a large extent, and improves the overall safety performance.

In this embodiment, before sending the driving signal to the thyristor, the method includes:

Obtain the zero-crossing signal of the power supply;

The time for sending the driving signal of the thyristor is set according to the zero-crossing signal.

It should be noted that the power supply signal is a pulse signal, that is, the power supply signal is a periodic high-low level type signal, and a zero point will be passed when the high level and the low level are converted. At the moment of the zero point, there is no power in the load circuit, and the switching of the on or off state of the thyristor at this moment will greatly reduce the loss of the thyristor and increase the service life of the thyristor. Therefore, the acquired zero-crossing signal is sent to the thyristor signal controller, and the sending time parameter of the drive signal is set according to the zero-crossing signal, so as to reduce the loss of the thyristor and increase the service life of the thyristor.

It can be known from the above technical scheme that the load loop detection method provided in this embodiment sends a drive signal to the thyristor, and the drive signal is used to indicate that the thyristor is working in the on state or the off state; obtains the load current sampled by the load detection circuit and the level signal converted from the load current, and the load current includes a first current sampled to flow through the load or a second current that does not flow through the load but flows through the load detection circuit, and the second current is less than the holding current of the thyristor; determines the working state of the thyristor or the load according to the drive signal and the level signal. Therefore, the detection of the state of the load and the thyristor can be realized, and the overall safety performance is improved.

It should be noted that, in each of the above embodiments, there is not necessarily a certain order between the above steps. A person skilled in the art can understand, based on the description of the embodiments of the present invention, that in different embodiments, the above steps may have different execution orders, that is, they may be executed in parallel, may be executed interchangeably, and so on.

Figure 3 is a structural schematic diagram of a load detection circuit provided by an embodiment of the present invention; specifically, please refer to Figures 2 and 3, a load detection circuit is used to detect the working state of a load circuit, the load circuit includes a thyristor T and a load L, the thyristor T is connected to the load L, and the load detection circuit includes a sampling module 10 and a control module 30.

The sampling module 10 is connected to the load L, and is used to sample the load current and convert the load current into a level signal, wherein the load current includes sampling a first current flowing through the load or a second current flowing through the load detection circuit without flowing through the load, and the second current is less than the holding current of the thyristor;

In some embodiments, the sampling module 10 collects the load current in various forms, which may be: when the load L and the thyristor T are both in normal working conditions and the thyristor T is turned on, the sampling module 10 collects the first current flowing through the load L; and when the load L is in an open circuit and the thyristor T is in the on state, the sampling module 10 collects the second current that does not flow through the load L but directly flows through the load detection circuit.

The control module 30 is connected to the sampling module 10 and the thyristor T respectively;

In some embodiments, the control module 30 has multiple signal input and output ports, and the multiple signal input and output ports are used to receive and output signals, thereby realizing signal interaction with other execution terminals or servers. Specifically, in this embodiment, the control module 30 is used to output the driving signal of the thyristor T and receive the zero-crossing signal of the power supply and the level signal of the load circuit, that is, it plays the role of driving and protecting the load circuit, and realizes the detection function of the load circuit.

Further, referring to FIG. 3 , the control module 30 includes:

at least one processor 31; and

A memory 32 communicatively connected to the at least one processor 31; wherein the memory 32 stores instructions executable by the at least one processor 31, and the instructions are executed by the at least one processor 31 so that the at least one processor 31 can be used to execute the load loop detection method of each of the aforementioned embodiments.

Please refer to FIG. 3 , the sampling module 10 includes: a sampling circuit 12 connected in parallel with the load L, and a shaping circuit 11 connected to the sampling circuit 12 and the control module 30;

The sampling circuit 12 is used to sample the load current in the load loop;

The shaping circuit 11 is used to convert the load current into a level signal.

In the embodiment of the present invention, the sampling circuit 12 is connected to the load circuit in parallel with the load L, and the resistance of the sampling circuit 12 is much greater than the resistance of the load L, so that the influence of the sampling circuit 12 in parallel with the load L on the load circuit can be ignored. In addition, when the load L is open-circuited, because the sampling circuit 12 and the load L are in parallel, the load circuit will form a loop of power supply-sampling circuit-thyristor-ground wire, and the detection circuit and one end of the thyristor T will not be suspended due to the open circuit state of the load L, and the state of the thyristor T or other components cannot be detected or obtained, so that the entire load circuit is in an uncertain state and forms a safety hazard.

It should be noted that, since the sampling circuit 12 of the present invention is another load with a larger resistance value relative to the load circuit, and the current after the power supply does not flow through the load but flows through the sampling circuit 12 is less than the holding current of the thyristor T, when the current flowing through the two ends of the thyristor T is less than the holding current, regardless of whether the driving signal input to the control end of the thyristor T is a working mode indicating that the thyristor T is turned on, the thyristor T is in a cut-off state, and the current is directly converted into a level signal after passing through the sampling module 10. At this time, the level signal obtained by the control module 30 is a periodic high and low level signal. The load detection circuit of this embodiment acts as a load when the load L is in an open circuit state, and can further detect the working state of the thyristor T, and will not cause one end of the thyristor T and the load detection circuit to be in a suspended state due to the open circuit state of the load L, and cannot detect the working state of the load circuit, thereby eliminating this potential safety hazard and improving the overall safety performance.

Specifically, please refer to FIG. 3 , the sampling circuit 12 includes: a first resistor R1 , one end of the first resistor R1 is connected to the other end of the load L and is connected to a power supply, and the other end of the first resistor R1 is connected to one end of the load L.

The sampling circuit 12 is not only composed of a single resistor, but also composed of multiple resistors with different connection modes. It is not limited to the type of resistor, but also can be an inductor or other components with large resistance. The sampling circuit 12 plays a current limiting role when the load L is in an open circuit state, pulling the current of the load loop down to the holding current of the thyristor T, so that the thyristor T is in a cut-off state, thereby playing a protective role.

Specifically, the shaping circuit 11 includes: a second resistor R2, a first diode D1, a second diode D2 and a first capacitor C1;

One end of the second resistor R2 is connected to one end of the load L, the other end of the second resistor R2 is connected to the cathode of the first diode D1 and the anode of the second diode D2, the anode of the first diode D1 is grounded, the cathode of the second diode D2 is connected to the forward voltage, one end of the first capacitor C1 is connected to the control module 30 and the other end of the second resistor R2, and the other end of the first capacitor C1 is grounded.

Furthermore, the shaping circuit 11 can be specifically divided into a current limiting unit, an amplitude limiting unit and a filtering unit;

The current limiting unit includes the second resistor R2, which is used to limit the current to prevent the load detection circuit from being damaged by excessive current;

The amplitude limiting unit includes a first diode D1 and a second diode D2, which are used to limit the voltage amplitude;

The filtering unit includes a first capacitor C1, which is used to filter the voltage signal.

The shaping circuit 11 of this embodiment is used to perform shaping processing on the level signal flowing through the load circuit, specifically including current limiting processing, amplitude limiting processing and filtering processing, so that there will be no other impurities in the level signal when it is sent to the control module, and it can be clearly recognized by the corresponding controller, thereby improving the accuracy of detection.

Specifically, referring to FIG. 5 , the load detection circuit further includes:

A protection circuit 20, which is connected between the control end of the thyristor T and the control module 30, and is used to prevent the driving voltage from damaging the thyristor T;

The protection circuit 20 includes a third resistor R3 and a second capacitor C2, one end of the second capacitor C2 is connected to the other end of the third resistor R3, the other end of the second capacitor C2 is connected to the control end of the thyristor T, and one end of the third resistor R3 is connected to the control module 30.

Specifically, referring to FIG. 6 , the load detection circuit further includes:

A RC step-down circuit 50, which is connected to the other end of the load L and is used to step down, stabilize and filter the power signal;

The RC step-down circuit 50 includes a fourth resistor R4, a third capacitor C3, a fifth diode D5, a voltage-stabilizing diode D6 and an electrolytic capacitor C4; one end of the fourth resistor R4 is connected to the power input end, and the other end is connected to one end of the third capacitor C3; the other end of the third capacitor C3 is connected to the cathode of the voltage-stabilizing diode D6 and the anode of the fifth diode D5; the anode of the voltage-stabilizing diode D6 is grounded; the cathode of the fifth diode D5 is connected to the anode of the electrolytic capacitor C4; the anode of the electrolytic capacitor C4 is connected to the forward voltage; and the cathode of the electrolytic capacitor C4 is grounded.

Specifically, the load detection circuit further includes:

A zero-crossing detection circuit 40, which is connected to the other end of the load L and the control module 30, and is used to perform zero-crossing detection on the power supply signal and send the acquired zero-crossing signal to the control module 30;

The zero-crossing detection circuit includes a third resistor R3, a third diode D3 and a fourth diode D4; one end of the third resistor R3 is connected to the power input end, the other end of the third resistor R3 is connected to the cathode of the third diode D3 and the anode of the fourth diode D4, the anode of the third diode D3 is grounded, the anode of the fourth diode D4 is connected to the control module 30, and the cathode of the fourth diode D4 is connected to the forward voltage.

In this embodiment, a sampling circuit is connected to the load circuit in parallel with the load, so that when the load is open, the load detection circuit and one end of the thyristor will not be left hanging, and a level signal can be provided to the load detection circuit, thereby making the working state of the thyristor detectable, avoiding the potential safety hazard of the load circuit being in an uncertain state due to one end of the load detection circuit and the thyristor being left hanging due to the load open, thereby improving the overall safety performance.

An embodiment of the present invention also provides an electronic device, including:

housing; and,

As the aforementioned load detection circuit, the load detection circuit is arranged in the housing.

Since this embodiment and the above embodiments are based on the same concept, the contents of this embodiment can refer to the above embodiments on the premise that the contents do not conflict with each other, and will not be repeated here.

The electronic device can execute the load circuit detection method in the above corresponding method embodiment, and has the corresponding functional modules and beneficial effects of the execution method. For technical details not described in detail in the electronic device embodiment, please refer to the load circuit detection method in the above corresponding method embodiment.

The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

Through the description of the above embodiments, a person of ordinary skill in the art can clearly understand that each embodiment can be implemented by means of software plus a general hardware platform, or of course by hardware. A person of ordinary skill in the art can understand that all or part of the processes in the method of the embodiment can be completed by hardware related to computer program instructions, and the program can be stored in a computer-readable storage medium, which, when executed, can include the processes of the embodiments of the methods. The storage medium can be a disk, an optical disk, a read-only memory (ROM) or a random access memory (RAM), etc.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. Under the concept of the present invention, the technical features in the above embodiments or different embodiments may also be combined, the steps may be implemented in any order, and there are many other changes in different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims (11)

1. A load detection circuit for detecting an operating state of a load circuit, the load circuit comprising a thyristor and a load, the thyristor being connected to the load, the load detection circuit comprising:

the sampling module is connected with the load and is used for sampling load current and converting the load current into a level signal, the load current comprises a first current flowing through the load or a second current flowing through the load detection circuit without flowing through the load, and the second current is smaller than the maintaining current of the silicon controlled rectifier;

The control module is connected with the sampling module and the silicon controlled rectifier;

wherein, the control module includes:

at least one processor; and

a memory communicatively coupled to the at least one processor; wherein the memory stores instructions executable by the at least one processor to enable the at least one processor to perform:

transmitting a driving signal to the controllable silicon, wherein the driving signal is used for indicating the controllable silicon to work in an on state or an off state;

acquiring a load current sampled by the load detection circuit and a level signal converted by the load current, wherein the load current comprises a first current which flows through the load or a second current which does not flow through the load but flows through the load detection circuit, and the second current is smaller than a maintaining current of the silicon controlled rectifier;

determining the working state of the controllable silicon or the load according to the driving signal and the level signal;

wherein, the sampling module includes: the sampling circuit is connected with the load in parallel, and the shaping circuit is connected with the sampling circuit and the control module;

The sampling circuit is used for sampling the load current in the load loop;

the shaping circuit is used for converting the load current into a level signal;

the shaping circuit includes: the second resistor, the first diode, the second diode and the first capacitor;

one end of the second resistor is connected with one end of the load, the other end of the second resistor is connected with the negative electrode of the first diode and the positive electrode of the second diode, the positive electrode of the first diode is grounded, the negative electrode of the second diode is connected with a forward voltage, one end of the first capacitor is connected with the control module and the other end of the second resistor, and the other end of the first capacitor is grounded.

2. The load detection circuit of claim 1, wherein: the sampling circuit includes: and one end of the first resistor is connected with the other end of the load and is connected with a power supply, and the other end of the first resistor is connected with one end of the load.

3. The load detection circuit of claim 1, wherein: the load detection circuit further includes:

the protection circuit is connected between the control end of the controllable silicon and the control module and is used for preventing the driving voltage from damaging the controllable silicon;

The protection circuit comprises a third resistor and a second capacitor, one end of the second capacitor is connected with the other end of the third resistor, the other end of the second capacitor is connected with the control end of the silicon controlled rectifier, and one end of the third resistor is connected with the control module.

4. The load detection circuit of claim 1, wherein: the load detection circuit further includes:

the resistor Rong Jiangya circuit is connected with the other end of the load and used for reducing, stabilizing and filtering the power supply signal;

the resistance-capacitance voltage reduction circuit comprises a fourth resistor, a third capacitor, a fifth diode, a voltage stabilizing diode and an electrolytic capacitor; one end of the fourth resistor is connected with the power input end, the other end of the fourth resistor is connected with one end of the third capacitor, the other end of the third capacitor is connected with the negative electrode of the voltage stabilizing diode and the positive electrode of the fifth diode, the positive electrode of the voltage stabilizing diode is grounded, the negative electrode of the fifth diode is connected with the positive electrode of the electrolytic capacitor, the positive electrode of the electrolytic capacitor is connected with positive voltage, and the negative electrode of the electrolytic capacitor is grounded.

5. The load detection circuit of claim 1, wherein: the load detection circuit further includes:

The zero-crossing detection circuit is connected with the other end of the load and the control module, and is used for detecting zero crossing of a power supply signal and sending the acquired zero-crossing signal to the control module;

the zero-crossing detection circuit comprises a third resistor, a third diode and a fourth diode; one end of the third resistor is connected with the power input end, the other end of the third resistor is connected with the negative electrode of the third diode and the positive electrode of the fourth diode, the positive electrode of the third diode is grounded, the positive electrode of the fourth diode is connected with the control module, and the negative electrode of the fourth diode is connected with the positive voltage.

6. A load loop detection method applied to the load detection circuit of any one of claims 1 to 5, wherein the load detection circuit is used for detecting the working state of a load loop, and the load loop comprises a silicon controlled rectifier and a load, and the silicon controlled rectifier is connected with the load.

7. The load circuit detection method according to claim 6, wherein: the determining the working state of the controllable silicon according to the driving signal and the level signal comprises the following steps:

and when the driving signal is used for indicating that the controllable silicon works in the cut-off state, determining the working state of the controllable silicon according to the level type of the level signal.

8. The method of claim 7, wherein determining the operating state of the thyristor according to the level type of the level signal comprises:

when the level signal is in a periodic high-low level, the silicon controlled rectifier is in a normal state;

and when the level signal is in a continuous low level, the silicon controlled rectifier is in a breakdown state or a short circuit state.

9. The load circuit detection method according to claim 8, wherein: when the silicon controlled rectifier is in a normal state, the determining the working state of the load according to the driving signal and the level signal comprises the following steps:

when the driving signal is used for indicating that the silicon controlled rectifier works in a conducting state and the level signal is in a periodic high-low level, the load is in an open-circuit state;

when the driving signal is used for indicating that the silicon controlled rectifier works in a conducting state and the level signal is continuously low level, the load is in a normal state.

10. The load circuit detection method according to claim 6, wherein: before the driving signal is sent to the controllable silicon, the method comprises the following steps:

acquiring a zero crossing signal of a power supply;

And setting the time for transmitting the driving signal of the controllable silicon according to the zero crossing signal.

11. An electronic device, comprising:

a housing; and a load detection circuit according to any one of claims 1 to 5, the load detection circuit being provided within the housing.