Control method, device and circuit for residual voltage release of terminal and storage medium

Abstract

The application relates to a control method, device and circuit of residual voltage release of a wiring terminal and a storage medium, wherein the control method of residual voltage release of the wiring terminal comprises the following steps: acquiring a reference discharge current when a circuit where the wiring terminal is located is in a power-off state; determining a duty cycle required for a switching tube in the circuit to be configured according to the reference discharge current; and controlling the switching tube according to the duty cycle to discharge the circuit to release the residual voltage of the wiring terminal. According to the method, the on-off of the switching tube in the circuit is controlled by the duty cycle when the circuit where the wiring terminal is located is in the power-off state, the circuit is discharged to release the residual voltage of the wiring terminal, the rapid drop of the residual voltage at the wiring terminal is realized, the safety is improved, and no additional hardware cost is increased.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of residual voltage release, and particularly relates to a control method and device for residual voltage release of a terminal, a circuit and a storage medium. BACKGROUND

[0002] When some circuits including an X capacitor are powered off during standby, there is residual voltage on the X capacitor (a capacitor for suppressing electromagnetic interference of a power supply) in a strong current filter circuit. When the power-off action occurs near an AC voltage peak, the residual voltage is the largest. However, the residual voltage is discharged slowly, and if the terminal is accidentally touched before the residual voltage is reduced to a safe voltage range, the human body can be harmed.

[0003] Currently, the main response to residual voltage is to increase a hardware discharge circuit, such as a discharge resistor connected in parallel across the X capacitor. However, this method needs to increase additional costs, and the discharge speed and standby loss are mutually restricted. The discharge speed is slow, the discharge current is uncontrollable, and the method cannot well solve the problem of safety hazards of the terminal on the strong current side after power-off. SUMMARY

[0004] To solve the technical problem of how to make the residual voltage of the terminal quickly decrease to a safe voltage range, the present application provides a control method and device for residual voltage release of a terminal, a circuit and a storage medium.

[0005] In a first aspect, the present application provides a control method for residual voltage release of a terminal, and the method comprises the following steps.

[0006] When a circuit in which the terminal is located is in a power-off state, a reference discharge current is acquired;

[0007] A duty cycle configured for a switch tube in the circuit is determined according to the reference discharge current;

[0008] The switch tube is controlled according to the duty cycle, the circuit is discharged, and residual voltage of the terminal is released;

[0009] Optionally, the circuit comprises a pre-stage of a rectifier bridge, the rectifier bridge and a post-stage of the rectifier bridge, the post-stage of the rectifier bridge is configured with a post-stage capacitor and the switch tube, and the pre-stage of the rectifier bridge is configured with an X capacitor and the terminal;

[0010] When a circuit in which the terminal is located is in a power-off state, a reference discharge current is acquired, comprising: when a circuit in which the X capacitor is located is in a power-off state, a reference discharge current is acquired;

[0011] Accordingly, discharging the circuit according to the duty ratio to release the residual voltage of the terminal includes discharging the post-stage capacitor according to the duty ratio to release the residual voltage of the X capacitor.

[0012] Optionally, the reference discharge current is obtained by:

[0013] The transition instruction signal is generated according to the peak voltage of the bus voltage; the bus voltage is the voltage supplied by the post-stage of the rectifier bridge for the load;

[0014] The bus voltage and the total disturbance of the post-stage of the rectifier bridge are observed, and an observation value is output;

[0015] The control signal is generated according to the transition instruction signal and the observation value, and the reference discharge current indicated by the control signal is obtained;

[0016] Optionally, the transition instruction signal is generated according to the peak voltage of the bus voltage, including:

[0017] The given instruction signal is obtained based on the peak voltage of the bus voltage, and a preset tracking step is obtained;

[0018] The transition instruction signal is determined according to the tracking step and the given instruction signal;

[0019] Optionally, the duty ratio configured for the switch tube in the circuit according to the reference discharge current is determined, including:

[0020] The current feedback signal is obtained, and a current loop error input signal is obtained according to the difference between the reference discharge current and the current feedback signal; the current feedback signal is the current signal of the loop in which the switch tube is located;

[0021] The current loop error input signal is proportionally integrated to obtain the duty ratio configured for the switch tube;

[0022] Optionally, the current feedback signal is obtained by:

[0023] The sampling voltage sampled by the sampling resistor is obtained; the sampling resistor is configured in the loop in which the switch tube is located in the post-stage of the rectifier bridge;

[0024] The resistance value and the amplification multiple of the sampling resistor are obtained;

[0025] The current feedback signal is calculated according to the resistance value, the amplification multiple and the sampling voltage;

[0026] Optionally, during the process of discharging the post-stage capacitor according to the duty ratio of the switch tube, the method further comprises:

[0027] determining that the bus voltage is less than a given voltage; the given voltage is greater than a peak voltage of the mains and less than a maximum voltage allowed to be reached when the circuit is operating normally;

[0028] stopping controlling the switch tube according to the duty cycle to stop discharging the post-stage capacitor if the bus voltage is greater than or equal to the given voltage;

[0029] Optionally, discharging the post-stage capacitor according to the duty cycle includes:

[0030] obtaining a preset working period of the switch tube;

[0031] controlling the switch tube to discharge the post-stage capacitor according to the working period and the duty cycle.

[0032] In a second aspect, the present application provides an X-capacitor residual voltage release device, the device comprising:

[0033] an obtaining module, configured to obtain a reference discharge current when a circuit where a terminal is located is in a power-off state;

[0034] a configuring module, configured to determine a duty cycle that needs to be configured for a switch tube in the circuit according to the reference discharge current;

[0035] a control module, configured to control the switch tube to discharge the circuit according to the duty cycle to release residual voltage of the terminal.

[0036] In a third aspect, the present application provides a terminal residual voltage release control circuit, the circuit comprising a controller, the controller being configured to execute the terminal residual voltage release control method in any one of the embodiments of the first aspect;

[0037] Optionally, a main chip of the circuit serves as the controller; during the process of residual voltage release performed by the main chip, a supply voltage of the main chip is greater than or equal to an under-voltage protection threshold.

[0038] In a fourth aspect, the present application provides an electronic device, comprising a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory complete mutual communication through the communication bus;

[0039] the memory is configured to store a computer program;

[0040] the processor is configured to execute the program stored on the memory, and implement the steps of the terminal residual voltage release control method in any one of the embodiments of the first aspect.

[0041] In a fifth aspect, the present application provides a computer readable storage medium, having stored thereon a computer program, which, when executed by a processor, implements the steps of the control method for residual voltage release of a terminal according to any one of the embodiments of the first aspect.

[0042] Compared with the prior art, the above technical solution provided by the embodiments of the present application has the following advantages:

[0043] The method provided by the embodiments of the present application, when the circuit where the terminal is located is in a power-off state, acquires a reference discharge current; determines a duty cycle that needs to be configured for a switch tube in the circuit according to the reference discharge current; and controls the switch tube according to the duty cycle to discharge the circuit to release the residual voltage of the terminal. The method, when the circuit where the terminal is located is in a power-off state, controls the on-off of the switch tube in the circuit through the duty cycle to discharge the circuit to release the residual voltage of the terminal, realizes the rapid drop of the residual voltage at the terminal, improves the safety, and does not increase any hardware cost. BRIEF DESCRIPTION OF DRAWINGS

[0044] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and serve to explain the principles of the present application together with the specification.

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows. Obviously, for those of ordinary skill in the art, other drawings can also be obtained based on these drawings without any creative effort.

[0046] Figure 1 A system architecture diagram of a control method for residual voltage release of a terminal according to an embodiment of the present application is provided.

[0047] Figure 2 A schematic diagram of a residual voltage release circuit of an X capacitor according to an embodiment of the present application is provided.

[0048] Figure 3 A flowchart of a control method for residual voltage release of a terminal according to an embodiment of the present application is provided.

[0049] Figure 4 A flowchart of a residual voltage release method of an X capacitor according to an embodiment of the present application is provided.

[0050] Figure 5 A flowchart of an active disturbance rejection energy outer loop control according to an embodiment of the present application is provided.

[0051] Figure 6A flowchart of current inner loop control provided by an embodiment of the present application;

[0052] Figure 7 A fixed resistance versus capacitor discharge curve provided by an embodiment of the present application;

[0053] Figure 8 A capacitor constant current discharge curve provided by an embodiment of the present application;

[0054] Figure 9 A structural diagram of a control device for releasing residual voltage of a terminal provided by an embodiment of the present application;

[0055] Figure 10 A structural diagram of an electronic device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0056] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described below in detail with reference to the accompanying drawings. Obviously, the described embodiments are only some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present application.

[0057] The first embodiment of the present application provides a control method for releasing residual voltage of a terminal, which can be applied to a system architecture as shown in Figure 1 The system architecture includes at least a residual voltage release circuit 101 and a controller 102. The controller 102 can collect signals of the residual voltage release circuit 101 and control the residual voltage release circuit 101. The system architecture can be a control circuit for releasing residual voltage of a terminal.

[0058] The method can be applied to the controller 102 in the system architecture, thereby controlling the residual voltage release circuit 101 and releasing residual voltage of a terminal in the residual voltage release circuit 101 in a power-off state, so as to improve the safety of the residual voltage release circuit 101.

[0059] For the residual voltage release circuit 101 including an X capacitor, releasing residual voltage of a terminal in the residual voltage release circuit 101 can also be understood as releasing residual voltage of the X capacitor connected to the terminal. At this time, the residual voltage release circuit 101, i.e., the circuit in which the X capacitor is located, can be various circuits including the X capacitor, such as a circuit with input of commercial power, including a rectifier bridge, a power factor correction (PFC) and a boost voltage. Figure 2 , Figure 2A schematic diagram of an X-capacitor residual voltage release circuit provided in the application is shown in FIG. 1. In the circuit, C1 and C2 are X-capacitors. When the power supply is powered off, the zero and live terminals at N and L are open, and the terminals are connected to the X-capacitors. If the residual voltage of the X-capacitors is not released, there is a risk of electric shock, and there is a safety hazard to personnel. DB1 is a rectifier bridge, which can convert alternating current into direct current when the circuit is working. C3 is a capacitor in the later stage of the circuit. RS1 is a sampling resistor. G1 is a switch tube, which is an insulated gate bipolar transistor (IGBT) in this example. However, the switch tube can also be other types, such as a metal-oxide-semiconductor field-effect transistor (MOSFET, or MOS tube). The type of switch tube, such as an IGBT, a MOS tube, or a triode, can be selected according to the needs. C4 is a bus capacitor, and the two sides of the bus capacitor can be connected to a load, which is not shown in the figure. The controller 102 collects signals of the circuit and controls part of the circuit, which is not shown, and does not mean that there is no connection.

[0060] The only way to release the voltage across the X-capacitors is the circuit in the later stage of the rectifier bridge. Due to the voltage clamping effect of the rectifier bridge, when the voltage across the X-capacitors is less than or equal to the voltage across the capacitor C3 in the later stage of the rectifier bridge, the voltage across the X-capacitors cannot be released. Due to the clamping effect of the diode D1, when the bus voltage is higher than the voltage across the capacitor C3, the equivalent impedance across the capacitor C3 is large, and the discharge is slow. Therefore, only when the voltage across the capacitor C3 is quickly released, can the voltage across the X-capacitors be quickly released.

[0061] It should be noted that the residual voltage release circuit 101 can be an air conditioner outdoor unit circuit, which is configured on a variable frequency air conditioner outdoor unit mainboard. By using the control method for residual voltage release of the terminal provided in the application, without increasing any hardware cost on the basis of the original components of the variable frequency air conditioner outdoor unit mainboard, after the outdoor unit is powered off, the IGBT is controlled to turn on and off, the capacitor in the later stage of the rectifier bridge is actively discharged, and then the X-capacitors are indirectly actively discharged, so as to quickly reduce the residual voltage of the terminal, and the discharge current is controllable, thereby improving the safety performance of the air conditioner.

[0062] Next, based on the system architecture and the schematic diagram of the X-capacitor residual voltage release circuit, the control method for residual voltage release of the terminal is described in detail. Figure 3 The method comprises the following steps.

[0063] In step 301, a reference discharge current is obtained when the circuit where the terminal is located is in a powered-off state.

[0064] Step 302, determine the duty cycle required for the switch tube in the circuit according to the reference discharge current;

[0065] Step 303, control the switch tube according to the duty cycle to discharge the circuit to release the residual voltage of the terminal.

[0066] The method discharges the circuit by controlling the on-off of the switch tube in the circuit through the duty cycle when the circuit where the terminal is located is in a power-off state, releases the residual voltage at the terminal position, realizes the rapid drop of the residual voltage at the terminal, improves the safety, and does not increase any hardware cost.

[0067] Specifically, for the circuit including the pre-stage of the rectifier bridge, the rectifier bridge, and the post-stage of the rectifier bridge (the post-stage of the rectifier bridge is configured with the post-stage capacitor and the switch tube, and the pre-stage of the rectifier bridge is configured with the X capacitor and the terminal), the control method for releasing the residual voltage of the terminal is actually also a method for releasing the residual voltage of the X capacitor, such as Figure 4 The method comprises:

[0068] Step 401, obtain the reference discharge current when the circuit where the X capacitor is located is in a power-off state;

[0069] Step 402, determine the duty cycle required for the switch tube in the circuit according to the reference discharge current, the switch tube and the post-stage capacitor are configured in the post-stage of the rectifier bridge of the circuit, and the X capacitor is configured in the pre-stage of the rectifier bridge of the circuit;

[0070] Step 403, control the switch tube according to the duty cycle to discharge the post-stage capacitor to release the residual voltage of the X capacitor.

[0071] The method actively discharges the post-stage capacitor by controlling the on-off of the switch tube in the post-stage of the rectifier bridge through the duty cycle when the circuit where the X capacitor is located is in a power-off state, and then indirectly actively discharges the X capacitor, realizes the rapid drop of the residual voltage of the terminal in the pre-stage of the rectifier bridge, improves the safety, and does not increase any hardware cost, so as to not produce additional loss caused by the additional hardware.

[0072] It should be noted that the post-stage of the rectifier bridge is configured with the post-stage capacitor and the switch tube in the embodiment, which does not mean that only the post-stage capacitor and the switch tube are configured, but actually other components can also be included, and the post-stage capacitor and the switch tube are only two items required, and other configurations of the specific circuit can be set as required, and the pre-stage of the rectifier bridge is the same, which will not be described here.

[0073] In one embodiment, the reference discharge current can be a preset fixed value or an observed value, and when it is an observed value, the acquisition method can be: generating a transition instruction signal according to the peak voltage of the bus voltage, observing the total disturbance of the bus voltage and the post-stage of the rectifier bridge, outputting the observed value, and generating a control signal according to the transition instruction signal and the observed value, and obtaining the reference discharge current indicated by the control signal.

[0074] When the reference discharge current is observed by the observer, the obtained reference discharge current value is more reasonable, and the specific observer is described in the subsequent embodiments.

[0075] In one embodiment, the reference discharge current can be a preset fixed value or an observed value, and when it is an observed value, the acquisition method can be: generating a transition instruction signal according to the peak voltage of the bus voltage, observing the total disturbance of the bus voltage and the post-stage of the rectifier bridge, outputting the observed value, and generating a control signal according to the transition instruction signal and the observed value, and obtaining the reference discharge current indicated by the control signal.

[0076] In this embodiment, the transition instruction signal can be obtained according to the preset tracking step and the given instruction signal.

[0077] In one embodiment, to determine the discharge according to the reference discharge current, the duty cycle configured for the switch tube in the circuit includes: obtaining a current feedback signal, obtaining a current loop error input signal according to the difference between the reference discharge current and the current feedback signal, the current feedback signal being the current signal of the loop where the switch tube is located, and performing proportional integral control on the current loop error input signal to obtain the duty cycle configured for the switch tube.

[0078] In one embodiment, in the process of discharging the post-stage capacitor, it is also necessary to detect whether the power is reconnected during the discharging process. If the X capacitor circuit has been powered on, the control of the switch tube needs to be stopped to avoid affecting the normal work of the circuit. The specific judgment method can include: determining that the bus voltage is less than a given voltage, the given voltage being greater than the peak voltage of the mains and less than the maximum voltage allowed during normal operation of the circuit, and if the bus voltage is greater than or equal to the given voltage, stopping the control of the switch tube according to the duty cycle to stop discharging the post-stage capacitor.

[0079] In one embodiment, in the process of discharging the post-stage capacitor, it is also necessary to detect whether the power is reconnected during the discharging process. If the X capacitor circuit has been powered on, the control of the switch tube needs to be stopped to avoid affecting the normal work of the circuit. The specific judgment method can include: determining that the bus voltage is less than a given voltage, the given voltage being greater than the peak voltage of the mains and less than the maximum voltage allowed during normal operation of the circuit, and if the bus voltage is greater than or equal to the given voltage, stopping the control of the switch tube according to the duty cycle to stop discharging the post-stage capacitor.

[0080] In this embodiment, the given voltage can be set to a voltage value higher than the preset value of the peak voltage of the mains, and the preset value can be 30V, 50V, 80V, etc., without specific limitation. For example, if the peak voltage of the mains is 310V, the given voltage can be set to 360V. During the discharging process of the subsequent capacitor, if the mains is not re-powered, the bus voltage will gradually decrease and will always be smaller than the given voltage, and the difference will become larger and larger. If the mains is re-powered and the bus voltage is greater than or equal to the given voltage after being boosted by the boost circuit, the control of the switch tube needs to be stopped to stop discharging the subsequent capacitor, so as to avoid interfering with the normal operation of the circuit.

[0081] It should be noted that the given voltage of 360V is only an example, and the given voltage only needs to be greater than 310V and less than the maximum voltage allowed during normal operation of the circuit. The specific value is not limited.

[0082] In one embodiment, the switch tube is controlled according to the duty cycle to discharge the subsequent capacitor, including: obtaining a preset working period of the switch tube, and controlling the switch tube to discharge the subsequent capacitor according to the working period and the duty cycle.

[0083] The switching frequency of the switch tube will be different according to different models and types. During the process of controlling the switch tube according to the duty cycle, the switching frequency of the switch tube can be referred to to set a suitable working period, so as to control the opening and closing of the switch tube according to the duty cycle. It should be understood that the time of opening or closing according to the duty cycle is greater than the minimum time allowed by the switch tube.

[0084] In one embodiment, the control method for the residual voltage release of the terminal adopts double-loop control for the duty cycle of the switch tube, wherein the outer loop adopts self-disturbance energy ring control, and the inner loop adopts current loop control. Here, the switch tube is exemplified by IGBT.

[0085] The self-disturbance energy outer loop control includes: Figure 5

[0086] Step 501, setting initial parameters, including given instruction signal, tracker step, observer gain, observer state initial value, disturbance compensation factor, feedback gain, etc.; wherein the tracker step can also be called tracking step, and the observer gain includes two observer gain coefficients β 01 and β 02 .

[0087] Step 502, generating a transition instruction signal from the given instruction signal through a differential tracker;

[0088] Step 503, obtaining voltage observation value and disturbance observation value through a state observer;

[0089] ​Step 504, the control signal is calculated by the state error feedback controller from the transition instruction signal and the state observation value.

[0090] In this embodiment, the active disturbance rejection energy outer loop control includes the following three parts: a first-order differential tracker, a second-order integral series extended state observer and a state error feedback controller.

[0091] The first-order differential tracker can be represented by the following formula (1):

[0092]

[0093] Where r0 is the tracking step, v is the given instruction signal, v1 is the transition instruction signal, The derivative of v1. The role of the differential tracker is to arrange the transition process for the step given instruction signal, and to suppress the disturbance to the system output caused by the given signal jump.

[0094] The second-order integral series extended state observer is as follows: formula (2):

[0095]

[0096] Where U0 is the bus voltage feedback value, z1 is the bus voltage observation value, z2 is the disturbance observation value, β 01 , β 02 is the observer gain coefficient, b0 is the disturbance compensation factor, and I is the output signal. The role of the extended state observer is to observe the bus voltage and the total disturbance of the system, and the observation value will be used as the input of the state error feedback controller.

[0097] The state error feedback controller is as follows: formula (3):

[0098]

[0099] Where ε is the state error, v1 is the transition instruction signal, z1 is the bus voltage observation value, z2 is the disturbance observation value, β 11 is the feedback gain, b0 is the disturbance compensation factor, I0 is the state error feedback control amount, and I is the output signal. The state error feedback controller generates the control signal from the given signal generated by the differential tracker and the state observation value of the extended state observer, and the control signal is also the output signal of the energy outer loop.

[0100] The above-mentioned active disturbance rejection energy outer loop control method can realize reliable control of the energy stored on the bus capacitor. Since the X capacitor value is generally much smaller than the bus capacitor value, during the active discharge process of the X capacitor after the external machine power failure, the bus voltage will not rise substantially, so the output of the energy outer loop will quickly tend to saturation. If the final bus voltage rises to the given voltage, that is, the energy outer loop output is not saturated, it means that the external machine is not in the power failure state.

[0101] Current inner loop control, such as Figure 6 , comprises:

[0102] Step 601, taking the output signal of the energy outer loop as the given signal of the current inner loop;

[0103] Step 602, taking the difference between the given signal of the current loop and the sampling signal of the actual discharge current to generate an error signal;

[0104] Step 603, generating the IGBT duty cycle control signal through the proportional integral link of the error signal.

[0105] In this embodiment, the current inner loop adopts PI control, taking the output signal of the energy outer loop as the given signal of the current inner loop, sampling the discharge current through the sampling resistor RS1 in Figure 2 , and obtaining the current feedback signal after data processing. The difference between the current given signal and the current feedback signal is taken to obtain the current loop error input signal, and the duty cycle is output after the PI control link, to control the discharge current and the equivalent impedance of the active discharge loop.

[0106] When the voltage across the capacitor C3 after the rectifier bridge drops to the safety threshold, the voltage across the X capacitor will also be below the safety threshold, at which time the active discharge operation can be stopped and the IGBT is turned off. At that time, even if someone mistakenly touches the terminal, it will not cause harm to the human body.

[0107] This active discharge method needs the participation of the controller in control, and the controller can also be the main chip in the circuit. When the main chip is controlled, the bus voltage should be kept above the under-voltage protection threshold of the switching power supply during the active discharge of the X capacitor, to maintain the normal work of the main chip in the control process. If there is a bus voltage discharge logic, the discharge process should be reasonably arranged according to the actual capacity of the mainboard, to ensure that the X capacitor completes the active discharge before the under-voltage protection of the switching power supply.

[0108] It should be noted that the role of the current inner loop is to keep the output current consistent with the given current (reference discharge current), and the output of the outer loop is actually the given current of the inner loop in the ideal state. Therefore, the current inner loop needs to control the duty cycle of the IGBT on-off to control the output current to follow the given current. PI control is a negative feedback control link, which controls the output through the error input to make the output signal follow the given signal. By PI controlling the current loop error input signal, the duty cycle of the IGBT on-off that needs to be finally obtained is output, that is, the output current can be controlled to follow the given current.

[0109] It should be noted that, in the residual voltage release process, as the bus voltage gradually decreases, in order to make the output current follow the given current, the duty cycle of the switch tube will gradually increase. In the first observation process, that is, the initial formula (2), I can be a preset value, and in the subsequent observation process, I in formula (2) is I in formula (3) in the last observation process, that is, the result of the state error feedback controller output is taken as the input parameter of the extended state observer in the next observation process, so that the result converges and the observation accuracy is improved.

[0110] As can be seen from the above embodiment, after the outdoor unit power failure, the output of the energy outer ring will quickly tend to saturation, and the current inner ring will control the current near the reference current of the energy outer ring output. The entire discharge process can be approximately processed as constant current discharge, and the current curve is as shown in Figure 8 The size of the discharge current can be adjusted and controlled by the saturation limiting value of the energy outer ring output. The current curve of the capacitor discharged by the fixed resistance is as shown in Figure 7 The current shows an exponential decay trend, and the discharge speed becomes slower and slower.

[0111] The charge released on the capacitor during the discharge process can be represented by Q=I×t, Figure 7 And Figure 8 The size of the current in formula (4) can measure the discharge speed of the capacitor, and the area surrounded by the current curve and the abscissa (time axis t) can measure the amount of charge released by the capacitor.

[0112] It should be noted that, Figure 8 The curve of the bus voltage from the peak voltage to the safe voltage in the capacitor discharge process is shown in formula (5), and the discharge current is approximately a fixed value.

[0113] The effects of the residual voltage release method of the present application and the residual voltage release method of the conventional scheme are verified as follows:

[0114] The discharge time is calculated by the fixed resistance discharge method (i.e. the scheme of parallelly connecting a discharge resistance across the X capacitor in the prior art): affected by factors such as standby loss, maximum dissipation power of the resistance, for example, if the resistance value of the discharge resistance is selected as 124kΩ and the capacitance value of the X capacitor is 2uF, the time required for the capacitor voltage to discharge from 310V to 36V is (wherein, U0 takes the peak voltage 310v of the mains 220V, and U takes the safe voltage 36v). In the discharge process, the initial discharge current value is 2.5mA, and the discharge current continuously decays (as the discharge proceeds, the voltage becomes lower and lower, and under the condition of the same resistance, the discharge current also becomes lower and lower), and the current is uncontrollable.

[0115] Discharge time is calculated in constant current discharge mode: in order to ensure the reliability of the device, the transient discharge current should be selected within 30A, which has sufficient safety margin here, and the average discharge current value is selected as 1A. The X capacitor value is 2uF, and the capacitor after the rectifier bridge is 2.2uF. The total capacitance is 4.4uF, and the time required for the capacitor voltage to discharge from 310V to 36V is

[0116]

[0117] It can be seen that from 310V to 36V, the discharge time of the scheme proposed in the application is about 1.2ms, which is much smaller than 534ms by connecting a discharge resistor in parallel across the capacitor, that is, the discharge time of the application is significantly shortened compared with the traditional means, and no additional external machine loss and hardware cost are increased.

[0118] It should be noted that the double-loop control in the embodiment, that is, the self-disturbance energy outer loop control and the current inner loop control, can be applied to each of the above embodiments of the application to obtain the duty cycle of the switching tube. The switching tube discharges the capacitor in the rear stage according to the duty cycle to release the residual voltage of the X capacitor, and can control the discharge current to achieve the effect of fast discharge.

[0119] Based on the same technical concept, the second embodiment of the application provides a control device for releasing residual voltage of a wiring terminal, as shown in Figure 9 The device comprises:

[0120] The acquisition module 901 is configured to acquire a reference discharge current when the circuit where the wiring terminal is located is in a power-off state.

[0121] The configuration module 902 is configured to determine a duty cycle that needs to be configured for a switching tube in the circuit according to the reference discharge current.

[0122] The control module 903 is configured to control the switching tube to discharge the circuit according to the duty cycle, so as to release the residual voltage of the wiring terminal.

[0123] The device controls the on-off of the switching tube in the circuit according to the duty cycle when the circuit where the wiring terminal is located is in a power-off state, discharges the circuit, and releases the residual voltage of the wiring terminal, so as to realize the rapid drop of the residual voltage at the wiring terminal and improve the safety without increasing any hardware cost.

[0124] As shown in Figure 10 The third embodiment of the application provides an electronic device, which comprises a processor 111, a communication interface 112, a memory 113 and a communication bus 114, wherein the processor 111, the communication interface 112 and the memory 113 complete communication with each other through the communication bus 114,

[0125] a memory 113, configured to store computer programs;

[0126] In one embodiment, the processor 111 is configured to implement the control method of residual voltage release of a terminal provided by any one of the preceding method embodiments when executing the programs stored in the memory 113.

[0127] acquire a reference discharge current when the circuit where the terminal is located is in a power-off state;

[0128] determine a duty cycle configured for a switch tube in the circuit according to the reference discharge current;

[0129] control the switch tube according to the duty cycle to discharge the circuit to release the residual voltage of the terminal. The communication bus mentioned above can be a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, or the like. The communication bus can be divided into an address bus, a data bus, a control bus, and the like. For ease of representation, only one thick line is used in the figure, but it does not mean that there is only one bus or only one type of bus.

[0130] The communication interface is configured to communicate between the terminal and other devices.

[0131] The memory can include a Random Access Memory (RAM) and can also include a non-volatile memory, such as at least one disk memory. Optionally, the memory can also be at least one storage device located away from the processor.

[0132] The processor mentioned above can be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), and the like; can also be a Digital Signal Processing (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA) or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component.

[0133] The fourth embodiment of the present application also provides a computer readable storage medium, which stores a computer program. The computer program is executed by a processor to implement the steps of the control method for residual voltage release of a terminal according to any one of the preceding method embodiments.

[0134] In the above embodiments, the implementation can be wholly or partially achieved by software, hardware, firmware, or any combination thereof. When implemented by software, the implementation can be wholly or partially in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed by a computer, the computer instructions wholly or partially generate the processes or functions described in the embodiments of the present application. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer readable storage medium or transferred from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions can be transferred from one website, computer, server, or data center to another website, computer, server, or data center through a wired (for example, coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (for example, infrared, wireless, microwave, etc.) manner. The computer readable storage medium can be any available medium accessible by a computer or a data storage device such as a server, data center, etc. integrated with one or more available media. The available medium can be a magnetic medium (for example, floppy disk, hard disk, magnetic tape), an optical medium (for example, DVD), or a semiconductor medium (for example, solid state disk (SSD)), etc.

[0135] It should 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. Moreover, the terms "comprises", "comprising", or any other variations 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 can include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without more limitations, an element defined by the phrase "comprising a... " does not exclude the existence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0136] It should be understood that the specific embodiments described herein merely exemplify the application and should not be considered limiting. In the description, the suffixes "module", "part" or "unit" used for components are merely intended for facilitation of explanation of the present application and by themselves do not have any specific meaning. Therefore, "module", "part" or "unit" can be mixedly used.

[0137] The above descriptions are merely specific embodiments of the present application to enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the generic principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the application. Accordingly, the present application is not 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.

Claims

1. A control method for releasing residual voltage at a terminal block, characterized in that, The method includes: When the circuit where the terminal block is located is in a power-off state, obtain the reference discharge current; Determining to discharge according to the reference discharge current requires configuring the duty cycle of the switching transistor in the circuit; The switching transistor is controlled according to the duty cycle to discharge the circuit and release the residual voltage at the terminal. The circuit includes a rectifier bridge pre-stage, a rectifier bridge, and a rectifier bridge post-stage. The rectifier bridge post-stage is configured with a post-stage capacitor and the switching transistor. The rectifier bridge pre-stage is configured with an X capacitor and the terminal block. When the circuit containing the terminal block is in a power-off state, a reference discharge current is obtained, including obtaining a reference discharge current when the circuit containing the X capacitor is in a power-off state. Correspondingly, the switching transistor is controlled according to the duty cycle to discharge the circuit to release the residual voltage at the terminal block, including controlling the switching transistor according to the duty cycle to discharge the post-stage capacitor to release the residual voltage of the X capacitor. The process of obtaining the reference discharge current includes: generating a transition command signal based on the peak voltage of the bus voltage; the bus voltage is the voltage supplied to the load by the downstream stage of the rectifier bridge; observing the bus voltage and the total disturbance of the downstream stage of the rectifier bridge, and outputting the observed value; generating a control signal based on the transition command signal and the observed value, and obtaining the reference discharge current indicated by the control signal. The process of generating a transition command signal based on the peak voltage of the bus voltage includes: obtaining a given command signal based on the peak voltage of the bus voltage, and obtaining a preset tracking step size; and determining the transition command signal based on the tracking step size and the given command signal. The process of determining the duty cycle required for the switching transistor in the circuit to discharge according to the reference discharge current includes: acquiring a current feedback signal; obtaining a current loop error input signal based on the difference between the reference discharge current and the current feedback signal; the current feedback signal being the current signal of the circuit in which the switching transistor is located; and performing proportional-integral control on the current loop error input signal to obtain the duty cycle required for the switching transistor. The process of obtaining the current feedback signal includes: obtaining the sampling voltage sampled by the sampling resistor; the sampling resistor is configured in the circuit where the switching transistor is located in the subsequent stage of the rectifier bridge; obtaining the resistance value and amplification factor of the sampling resistor; and calculating the current feedback signal based on the resistance value, the amplification factor, and the sampling voltage.

2. The method according to claim 1, characterized in that, During the process of discharging the subsequent capacitor by controlling the switching transistor according to the duty cycle, the method further includes: The bus voltage is determined to be less than a given voltage; the given voltage is greater than the peak voltage of the mains power and less than the maximum voltage that the circuit can reach during normal operation. If the bus voltage is greater than or equal to the given voltage, stop controlling the switching transistor according to the duty cycle to stop discharging the downstream capacitor.

3. The method according to claim 1, characterized in that, Controlling the switching transistor according to the duty cycle to discharge the subsequent capacitor includes: Obtain the preset duty cycle of the switching transistor; The switching transistor is controlled to discharge the subsequent capacitor according to the working cycle and the duty cycle.

4. A control device for releasing residual voltage at a terminal block, characterized in that, The device includes: The acquisition module is used to acquire the reference discharge current when the circuit where the terminal block is located is in a power-off state; A configuration module is used to determine the duty cycle that needs to be configured for the switching transistors in the circuit when discharging according to the reference discharge current; The control module is used to control the switching transistor according to the duty cycle to discharge the circuit and release the residual voltage at the terminal. The circuit includes a rectifier bridge pre-stage, a rectifier bridge, and a rectifier bridge post-stage. The rectifier bridge post-stage is configured with a post-stage capacitor and the switching transistor. The rectifier bridge pre-stage is configured with an X capacitor and the terminal block. When the circuit containing the terminal block is in a power-off state, a reference discharge current is obtained, including obtaining a reference discharge current when the circuit containing the X capacitor is in a power-off state. Correspondingly, the switching transistor is controlled according to the duty cycle to discharge the circuit to release the residual voltage at the terminal block, including controlling the switching transistor according to the duty cycle to discharge the post-stage capacitor to release the residual voltage of the X capacitor. The process of obtaining the reference discharge current includes: generating a transition command signal based on the peak voltage of the bus voltage; the bus voltage is the voltage supplied to the load by the downstream stage of the rectifier bridge; observing the bus voltage and the total disturbance of the downstream stage of the rectifier bridge, and outputting the observed value; generating a control signal based on the transition command signal and the observed value, and obtaining the reference discharge current indicated by the control signal. The process of generating a transition command signal based on the peak voltage of the bus voltage includes: obtaining a given command signal based on the peak voltage of the bus voltage, and obtaining a preset tracking step size; and determining the transition command signal based on the tracking step size and the given command signal. The process of determining the duty cycle required for the switching transistor in the circuit to discharge according to the reference discharge current includes: acquiring a current feedback signal; obtaining a current loop error input signal based on the difference between the reference discharge current and the current feedback signal; the current feedback signal being the current signal of the circuit in which the switching transistor is located; and performing proportional-integral control on the current loop error input signal to obtain the duty cycle required for the switching transistor. The process of obtaining the current feedback signal includes: obtaining the sampling voltage sampled by the sampling resistor; the sampling resistor is configured in the circuit where the switching transistor is located in the subsequent stage of the rectifier bridge; obtaining the resistance value and amplification factor of the sampling resistor; and calculating the current feedback signal based on the resistance value, the amplification factor, and the sampling voltage.

5. A control circuit for releasing residual voltage at a terminal block, characterized in that, The circuit includes a controller for executing the control method for releasing residual voltage at the terminals as described in any one of claims 1-3.

6. The circuit according to claim 5, characterized in that, The main chip of the circuit serves as the controller; during the residual voltage release process of the main chip, the supply voltage of the main chip is greater than or equal to the undervoltage protection threshold.

7. An electronic device, characterized in that, It includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; A processor, when executing a program stored in a memory, implements the steps of the control method for releasing residual voltage at the terminal blocks as described in any one of claims 1-3.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the control method for releasing residual voltage at the terminal as described in any one of claims 1-3.

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