Power supply circuit, control method thereof and electronic equipment

Abstract

The embodiment of the invention relates to the technical field of electronics, provides a power supply circuit, a control method thereof and electronic equipment, and aims to control power supply of a brake coil through the power supply circuit so as to reduce release response time and noise of a brake under a normal working condition and further improve comfort. The power supply circuit comprises an AC source module, a first switch module, an AC-DC conversion module, a voltage conversion module, a follow current module, a second switch module and an energy absorption module. The first switch module and the AC / DC conversion module are connected in series between the first end and the second end of the AC source module; the two input ends of the voltage conversion module are electrically connected with the positive electrode and the negative electrode of the alternating current and direct current conversion module respectively. The follow current module, the second switch module and the energy absorption module are sequentially connected in series between the positive electrode and the negative electrode of the voltage conversion module; the brake coil and the energy absorption module are arranged in parallel.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of electronic technology, and in particular to a power supply circuit and a control method thereof, and an electronic device. Background Art

[0002] Elevators have been widely used in residential, shopping malls, office buildings and other fields. The performance of elevator braking directly affects the safety of passengers. There are many factors that affect the braking of elevators. Among them, the output voltage of the brake power supply plays an important role in controlling the action of the brake. When the brake is released, the safety and comfort of the elevator will be affected. Generally, the elevator needs to be stopped under two working conditions. The first working condition (i.e. normal working condition) is the elevator stopping under normal conditions, and the other working condition (i.e. emergency working condition) is the rapid braking under emergency conditions such as emergency stop or elevator overspeed. Under the first working condition, in order to improve the comfort of passengers, the release speed of the brake needs to be appropriately slowed down, that is, there is no need to quickly close the gate. Under the second working condition, the brake needs to respond quickly, safety is prioritized, and comfort becomes a secondary requirement. At present, the brake response time under the first working condition is long, the noise is loud, and the comfort is not high, which urgently needs to be improved. Summary of the invention

[0003] The embodiments of the present application provide a power supply circuit and a control method thereof, and an electronic device, the purpose of which is to control the power supply of a brake coil through the power supply circuit, thereby reducing the release response time and noise of the brake under normal working conditions, thereby improving comfort.

[0004] According to some embodiments of the present application, the embodiments of the present application provide a power supply circuit for supplying power to a brake coil; the power supply circuit comprises: an AC source module, a first switch module, an AC / DC conversion module, a voltage conversion module, a freewheeling module, a second switch module and an energy absorption module;

[0005] The first switch module and the AC / DC conversion module are arranged in series between the first end and the second end of the AC source module; the two input ends of the voltage conversion module are electrically connected to the positive electrode and the negative electrode of the AC / DC conversion module respectively; the freewheeling module, the second switch module and the energy absorption module are arranged in series between the positive electrode and the negative electrode of the voltage conversion module in sequence; the brake coil is arranged in parallel with the energy absorption module;

[0006] The AC source module is used to provide an AC signal to the AC-DC conversion module; the first switch module is used to remain disconnected during the release period of the brake and remain closed during the lifting period of the brake; the AC-DC conversion module is used to convert the AC signal output by the AC source module into a first DC signal during the lifting period of the brake; the voltage conversion module is used to convert the first DC signal output by the AC-DC conversion module into a second DC signal during the lifting period of the brake, wherein the voltage value of the second DC signal is different from that of the first DC signal;

[0007] The second switch module is used to remain open in a first period of time within the release cycle of the brake, and remain closed in other periods except the first period of time, wherein the first period of time is any period of time within the release cycle of the brake;

[0008] The freewheeling module is used to form a freewheeling loop with the second switch module, the brake coil and the voltage conversion module when the second switch module remains closed;

[0009] The energy absorption module is used to absorb the energy released by the brake coil when the second switch module remains disconnected.

[0010] According to some embodiments of the present application, the starting time of the first time period is greater than the starting time of the release cycle of the brake, and the ending time of the first time period is less than the ending time of the release cycle of the brake.

[0011] According to some embodiments of the present application, the duration of the first time period is the time required for the energy absorption module to absorb a preset energy value, and the percentage range of the preset energy value to the energy value released by the brake coil is [40%, 80%].

[0012] According to some embodiments of the present application, the starting time of the first time period is greater than the starting time of the release cycle of the brake, and the ending time of the first time period is equal to the ending time of the release cycle of the brake.

[0013] According to some embodiments of the present application, the voltage conversion module includes a transformer, the second switch module includes a first MOS tube or a first crystal triode, the freewheeling module includes a first crystal diode, and the energy absorption module includes a voltage regulator tube and a second crystal diode connected in series;

[0014] The two ends of the primary coil of the transformer are electrically connected to the positive and negative electrodes of the AC / DC conversion module respectively, the positive electrode of the secondary coil of the transformer is electrically connected to the positive electrode of the first crystal diode, the negative electrode of the first crystal diode is electrically connected to the first end of the first MOS tube or the first crystal triode, the second end of the first MOS tube or the first crystal triode is electrically connected to the positive electrode of the voltage regulator tube, the negative electrode of the voltage regulator tube is electrically connected to the negative electrode of the second crystal diode, the positive electrode of the second crystal diode is electrically connected to the negative electrode of the secondary coil of the transformer, one end of the brake coil is electrically connected to the positive electrode of the voltage regulator tube, and the other end is electrically connected to the positive electrode of the second crystal diode.

[0015] According to some embodiments of the present application, the power supply circuit also includes a first capacitor, one end of which is electrically connected to the cathode of the first crystal diode, and the other end of which is electrically connected to the cathode of the secondary coil of the transformer.

[0016] According to some embodiments of the present application, the AC source module includes an AC source, the first switch module includes a first group of contact switches and a second group of contact switches, both groups of contact switches include a contact switch of a first relay and a contact switch of a second relay connected in series, and the AC-DC conversion module includes a rectifier;

[0017] The first end of the AC source, the first group of contact switches and the first input end of the rectifier are electrically connected in sequence, and the second end of the AC source, the second group of contact switches and the second input end of the rectifier are electrically connected in sequence.

[0018] According to some embodiments of the present application, the power supply circuit further includes a resistor, a second capacitor, and a second MOS tube or a second transistor;

[0019] One end of the resistor is electrically connected to the positive electrode of the rectifier, and the other end is electrically connected to the first end of the primary coil of the transformer; the first end of the second MOS tube or the second transistor is electrically connected to the second end of the primary coil of the transformer; the second end of the second MOS tube or the second transistor is electrically connected to the negative electrode of the rectifier; one end of the second capacitor is electrically connected to the negative electrode of the rectifier, and the other end is electrically connected to the first end of the primary coil of the transformer.

[0020] According to some embodiments of the present application, another aspect of the embodiments of the present application provides an electronic device, including a brake coil and the above-mentioned power supply circuit.

[0021] According to some embodiments of the present application, the embodiments of the present application provide a control method based on the above power supply circuit, including:

[0022] During the release cycle of the brake, the first switch module controlling the power circuit remains disconnected, and the second switch module controlling the power circuit remains disconnected during the first time period during the release cycle of the brake and remains closed during other time periods except the first time period, wherein the first time period is any time period within the release cycle of the brake.

[0023] The embodiment of the present application provides a power supply circuit and a control method thereof, and an electronic device, in which, during the release cycle of the brake, the first switch module remains disconnected, and power cannot be supplied to the brake coil; during the first period of the release cycle of the brake, the second switch module remains disconnected, and at this time, the brake coil quickly releases a large amount of energy through the energy absorption module; during the other periods of the release cycle of the brake except the first period, the second switch module remains closed, and at this time, the freewheeling module, the second switch module, the brake coil and the voltage conversion module form a freewheeling loop, and the brake coil slowly releases the remaining energy through the freewheeling loop. Compared with the prior art that uses a freewheeling loop to release the energy of the brake coil during the release cycle of the brake, the power supply circuit provided by the embodiment of the present application can significantly reduce the release response time and noise of the brake under normal working conditions, thereby improving comfort. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] One or more embodiments are exemplarily illustrated by the pictures in the corresponding drawings. These exemplified descriptions do not constitute a limitation on the embodiments. Unless otherwise specified, the pictures in the drawings do not constitute a scale limitation. In order to more clearly illustrate the embodiments of the present application or the technical solutions in the traditional technology, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 A schematic diagram of a power supply circuit provided in an embodiment of the present application;

[0026] Figure 2 A timing diagram of four brake action signals provided in an embodiment of the present application;

[0027] Figure 3 A schematic diagram of a brake inductance discharge curve under normal working conditions provided in an embodiment of the present application;

[0028] Figure 4 A schematic diagram of a brake inductance discharge curve a in a freewheeling state provided in an embodiment of the present application;

[0029] Figure 5 A schematic diagram of the brake inductance discharge curve b in the freewheeling state provided in an embodiment of the present application. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in combination with the specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0031] In the description of the embodiments of the present application, "at least one" means one or more, "multiple" means two or more, and "at least one group" means one or more groups, unless otherwise clearly and specifically defined.

[0032] In the description of the embodiments of the present application, technical terms such as "first" and "second" are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features.

[0033] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0034] In the description of the embodiments of the present application, when a certain component “includes” another component, unless otherwise stated, other components are not excluded and other components may be further included.

[0035] The present application embodiment provides a power supply circuit for supplying power to a brake coil; Figure 1 As shown, the power supply circuit includes: an AC source module 1, a first switch module 2, an AC / DC conversion module 3, a voltage conversion module 4, a freewheeling module 5, a second switch module 6 and an energy absorption module 7.

[0036] refer to Figure 1 As shown, the first switch module 2 and the AC / DC conversion module 3 are arranged in series at the first end of the AC source module 1 (such as Figure 1 L end as shown) and the second end (as shown Figure 1The two input terminals of the voltage conversion module 4 are electrically connected to the positive and negative poles of the AC / DC conversion module 3 respectively; the freewheeling module 5, the second switch module 6 and the energy absorption module 7 are sequentially arranged in series between the positive and negative poles of the voltage conversion module 4; the brake coil L is arranged in parallel with the energy absorption module 7.

[0037] Among them, the AC source module is used to provide an AC signal to the AC-DC conversion module; the first switch module is used to remain disconnected during the release period of the brake and remain closed during the lifting period of the brake; the AC-DC conversion module is used to convert the AC signal output by the AC source module into a first DC signal during the lifting period of the brake; the voltage conversion module is used to convert the first DC signal output by the AC-DC conversion module into a second DC signal during the lifting period of the brake, wherein the voltage values ​​of the second DC signal and the first DC signal are different.

[0038] The second switch module is used to remain disconnected in the first time period within the release cycle of the brake, and remain closed in other time periods except the first time period, wherein the first time period is any time period within the release cycle of the brake; the freewheeling module is used to form a freewheeling loop with the second switch module, the brake coil and the voltage conversion module when the second switch module remains closed; the energy absorption module is used to absorb the energy released by the brake coil when the second switch module remains disconnected.

[0039] The above-mentioned power supply circuit is used to supply power to the brake coil; when the brake coil is energized, the brake can be controlled to be in a released state (i.e., the brake is released); when the brake coil is not energized, the brake can be controlled to be in a locked state (i.e., the brake is locked).

[0040] The specific structure of the AC source module is not limited. By way of example, the AC source module may include an AC source having a voltage of 220V.

[0041] The specific structure of the first switch module is not limited. For example, the first switch module may include at least one contact switch or at least one group of contact switches; or the first switch module may include other types of switches.

[0042] The AC / DC conversion module may include a rectifier. The type of the rectifier is not limited here, as long as it can convert AC into DC.

[0043] The voltage conversion module may include a transformer or a DCDC converter, etc., and the first DC signal is converted into a second DC signal.

[0044] The above-mentioned freewheeling module may include at least one crystal diode. The type of the crystal diode is not limited here and can be selected according to actual requirements.

[0045] The above-mentioned second switch module may include at least one MOS (Metal Oxide Semiconductor, N-type metal oxide semiconductor) tube or at least one transistor, etc. The MOS tube may be an NMOS (Negative-channelMetal Oxide Semiconductor, N-type metal oxide semiconductor) tube or a PMOS (Positive-channelMetal Oxide Semiconductor, P-type metal oxide semiconductor) tube, which is not limited here; the transistor may be an NPN transistor or a PNP transistor, which is not limited here.

[0046] The energy absorption module may include a voltage regulator tube and a crystal diode connected in series, and may also include other structures, which are not limited here.

[0047] In the power supply circuit provided by the embodiment of the present application, during the release cycle of the brake, the first switch module remains disconnected, and power cannot be supplied to the brake coil; during the first period of the release cycle of the brake, the second switch module remains disconnected, and at this time the brake coil quickly releases a large amount of energy through the energy absorption module; during the other periods of the release cycle of the brake except the first period, the second switch module remains closed, and at this time the freewheeling module, the second switch module, the brake coil and the voltage conversion module form a freewheeling loop, and the brake coil slowly releases the remaining energy through the freewheeling loop. Compared with the prior art that uses a freewheeling loop to release the energy of the brake coil during the release cycle of the brake, the power supply circuit provided by the embodiment of the present application can significantly reduce the release response time and noise of the brake under normal working conditions, thereby improving comfort.

[0048] It should be noted that the duration of the first time period and the position of the time period within the brake release cycle will directly affect the comfort.

[0049] The time period position of the first time period within the release cycle of the brake is provided below.

[0050] In one or more embodiments, reference Figure 2 As shown in the curve a, the starting time t2 of the first time period M1 is greater than the starting time t0 of the release cycle M of the brake, and the ending time t3 of the first time period M1 is less than the ending time t1 of the release cycle M of the brake.

[0051] If the duration of the first period is too long, the brake coil may quickly release all the energy through the energy absorption module, so that the brake will stop quickly, which is not conducive to further reducing noise and further improving comfort; if the duration of the first period is too short, the brake coil can only release a small amount of energy through the energy absorption module, which is not conducive to further shortening the release response time; therefore, the duration of the first period needs to be compatible with shortening the response time and improving comfort.

[0052] In order to better shorten the response time, further reduce noise and improve comfort, the duration of the first period is the time required for the energy absorption module to absorb the preset energy value, and the percentage of the preset energy value to the energy value released by the brake coil is in the range of [40%, 80%]. The percentage of the preset energy value to the energy value released by the brake coil can be 40%, 50%, 60%, 70% or 80%, etc.

[0053] Under normal working conditions, only the freewheeling circuit is used to discharge the brake coil. Figure 1 As shown, at this time, the second switch module remains closed in the brake release period M0, and the corresponding discharge curve of the brake coil in the freewheeling state can be as follows: Figure 3 As shown, after a large number of measurements, the time required for the brake coil current to slowly drop from 100% to the critical value of brake release (about 20%) is between 400 and 800 ms, which exceeds the regulatory requirement of 500 ms.

[0054] Figure 2 The discharge curve of the brake coil in the freewheeling state corresponding to the middle curve a can be shown as Figure 4 As shown, in the 3-9ms period at the beginning of the brake release cycle, the second switch module is disconnected, and the brake coil is rapidly discharged through the energy absorption module, and the energy is released to about 30%; then the second switch module is closed, and the brake coil slowly releases the remaining energy through the freewheeling circuit; Figure 3 In comparison, this method can significantly shorten the release response time of the brake while ensuring good elevator comfort, while better controlling noise. This method can adopt different follow-up control times for different brakes, and has more extreme performance.

[0055] Another time period position of the first time period within the brake release cycle is provided below.

[0056] In one or more embodiments, reference Figure 2 As shown in the curve b, the starting time t4 of the first time period M1 is greater than the starting time t0 of the release cycle M of the brake, and the ending time t5 of the first time period M1 is equal to the ending time t5 of the release cycle M of the brake.

[0057] Here, the duration of the first period can be selected as required, as long as the overall release response time meets the regulatory requirements. For example, the duration of the first period can range from [10ms, 200ms], and the duration of the first period can be 10ms, 20ms, 30ms, 50ms, 70ms, 100ms, 150ms or 200ms, etc.

[0058] Figure 2 The discharge curve of the brake coil in the freewheeling state corresponding to the middle curve b can be shown as Figure 5 As shown, in the early and middle stages of the brake release cycle, the second switch module is closed, and the brake coil slowly releases part of the energy through the freewheeling circuit. The duration of this stage can be 300-400ms; in the late stage of the brake release cycle, the second switch module is disconnected, and the brake coil quickly discharges the remaining energy through the energy absorption module, thereby shortening the brake release response time and ensuring that regulatory requirements are met. Figure 3 In comparison, this method can shorten the release response time of the brake and adopt the same follow-up control time for different brakes, thereby obtaining more consistent noise control and response time. It has wider adaptability and consistency and is more suitable for general scenarios.

[0059] In addition, refer to Figure 2 As shown, in an emergency condition (i.e., when emergency braking is required), the second switch module can be quickly disconnected (such as disconnecting the second switch module at time t7), so that the brake coil is quickly discharged through the energy absorption module, thereby achieving rapid braking.

[0060] In one or more embodiments, reference Figure 1 As shown, the voltage conversion module 3 includes a transformer B, the second switch module 6 includes a first MOS tube or a first crystal triode T1, the freewheeling module 5 includes a first crystal diode D1, and the energy absorption module 7 includes a voltage regulator tube DZ and a second crystal diode D2 connected in series. Figure 1 The second switch module 6 including the first transistor T1 is taken as an example for illustration.

[0061] refer to Figure 1As shown, the two ends of the primary coil L1 of the transformer B are electrically connected to the positive and negative electrodes of the AC / DC conversion module 3 respectively, the positive electrode of the secondary coil L2 of the transformer B is electrically connected to the positive electrode of the first crystal diode D1, the negative electrode of the first crystal diode D1 is electrically connected to the first end of the first MOS tube or the first crystal triode T1, the second end of the first MOS tube or the first crystal triode T1 is electrically connected to the positive electrode of the voltage regulator tube DZ, the negative electrode of the voltage regulator tube DZ is electrically connected to the negative electrode of the second crystal diode D2, the positive electrode of the second crystal diode D2 is electrically connected to the negative electrode of the secondary coil L2 of the transformer B, one end of the brake coil L is electrically connected to the positive electrode of the voltage regulator tube DZ, and the other end is electrically connected to the positive electrode of the second crystal diode D2.

[0062] The first MOS tube may include a source, a drain and a gate. The first end of the first MOS tube may be a source end and the second end may be a drain end; or, the first end of the first MOS tube may be a drain end and the second end may be a source end, which is not limited here and can be determined according to the type of the first MOS tube. The gate end of the first MOS tube may be connected to a driving voltage, so that the first MOS tube is opened or closed under the control of the driving voltage. The first transistor may include a base, a collector and an emitter. The first end of the first transistor may be a collector end and the second end may be an emitter end; or, the first end of the first transistor may be an emitter end and the second end may be a collector end, which is not limited here and can be determined according to the type of the first transistor. Figure 1 In the figure, the first transistor T1 is illustrated as a PNP transistor. At this time, the first end of the first transistor T1 is the emitter terminal e, and the second end is the collector terminal c.

[0063] The above-mentioned series-connected voltage regulator and the second crystal diode can form a TVS tube (Transient Voltage Suppressor), which has an extremely fast response time and a relatively high surge absorption capacity. When its two ends are subjected to a momentary high-energy impact, the TVS tube can change the impedance value between the two ends from high impedance to low impedance at a very high speed to absorb a momentary large current and clamp the voltage between its two ends to a predetermined value, thereby protecting the subsequent circuit components from the impact of transient high-voltage spike pulses.

[0064] In one or more embodiments, in order to filter the signal generated by the transformer to obtain a signal with better quality, reference Figure 1 As shown, the power supply circuit also includes a first capacitor C1, one end of the first capacitor C1 is electrically connected to the cathode of the first crystal diode D1, and the other end is electrically connected to the cathode of the secondary coil L2 of the transformer B; the first capacitor C1 can filter the signal transmitted by the secondary coil L2 to reduce noise.

[0065] In one or more embodiments, reference Figure 1 As shown, the AC source module 1 includes an AC source AC, the first switch module 2 includes a first group of contact switches 21 and a second group of contact switches 22, both groups of contact switches include a contact switch K1 of a first relay and a contact switch K2 of a second relay connected in series, and the AC-DC conversion module 3 includes a rectifier TB; the first end of the AC source AC, the first group of contact switches 21 and the first input end of the rectifier TB are electrically connected in sequence, and the second end of the AC source AC, the second group of contact switches 22 and the second input end of the rectifier TB are electrically connected in sequence.

[0066] The brake coil can only be powered when the first and second contact switches are closed at the same time; when any one of the first and second contact switches is disconnected, the brake coil is powered off.

[0067] In one or more embodiments, reference Figure 1 As shown, the power supply circuit also includes a resistor R, a second capacitor C2 and a second MOS tube or a second transistor T2; one end of the resistor R is electrically connected to the positive electrode of the rectifier TB, and the other end is electrically connected to the first end of the primary coil L1 of the transformer B; the first end of the second MOS tube or the second transistor T2 is electrically connected to the second end of the primary coil L1 of the transformer B; the second end of the second MOS tube or the second transistor T2 is electrically connected to the negative electrode of the rectifier; one end of the second capacitor C2 is electrically connected to the negative electrode of the rectifier TB, and the other end is electrically connected to the first end of the primary coil L1 of the transformer B.

[0068] Figure 1 The second transistor T2 is used as an example for illustration. The description of the first end and the second end of the second MOS transistor and the second transistor can refer to the description of the first MOS transistor and the first transistor, which will not be repeated here. Figure 1 In the embodiment, the second transistor T2 and the first transistor T1 are both PNP transistors.

[0069] The resistor can be pre-charged to play a voltage-dividing role. The second capacitor also has a filtering effect to improve signal quality and reduce noise. The second MOS tube or the second transistor can perform PWM (Pulse Width Modulation) processing on the signal to achieve signal wave spreading.

[0070] In one or more embodiments, in order to better control the first switch module and the second switch module, the power supply circuit further includes a control module, and the control module is used to control the opening and closing of the first switch module and the second switch module.

[0071] The embodiment of the present application also provides an electronic device, including a brake coil and the above-mentioned power supply circuit; the brake coil is controlled by the power supply circuit, that is, during the release cycle of the brake, the first switch module remains disconnected, and power cannot be supplied to the brake coil; during the first period of the release cycle of the brake, the second switch module remains disconnected, at which time the brake coil quickly releases a large amount of energy through the energy absorption module; during the other periods of the release cycle of the brake except the first period, the second switch module remains closed, at which time the freewheeling module, the second switch module, the brake coil and the voltage conversion module form a freewheeling loop, and the brake coil slowly releases the remaining energy through the freewheeling loop. Compared with the prior art that uses a freewheeling loop to release the energy of the brake coil during the release cycle of the brake, the electronic device provided by the embodiment of the present application can significantly reduce the release response time and noise of the brake under normal working conditions, thereby improving comfort.

[0072] The electronic device may be an elevator, which may be used in various buildings such as residences, office buildings, shopping malls, etc. Under normal working conditions, the electronic device has a short brake release response time, low noise, and good comfort.

[0073] The present application further provides a control method based on the above power supply circuit, including:

[0074] S1. During the release cycle of the brake, the first switch module of the control power circuit remains disconnected, the second switch module of the control power circuit remains disconnected during the first time period of the brake release cycle, and remains closed during other time periods except the first time period, wherein the first time period is any time period within the release cycle of the brake.

[0075] For the relevant description of the power supply circuit involved in the control method, reference can be made to the aforementioned embodiments and will not be repeated here.

[0076] By executing the above control method, it can be achieved that during the release cycle of the brake, the first switch module remains disconnected, and power cannot be supplied to the brake coil; during the first period of the brake release cycle, the second switch module remains disconnected, and the brake coil quickly releases a large amount of energy through the energy absorption module; during the other periods of the brake release cycle except the first period, the second switch module remains closed, and the freewheeling module, the second switch module, the brake coil and the voltage conversion module form a freewheeling loop, and the brake coil slowly releases the remaining energy through the freewheeling loop. Through this control method, the release response time and noise of the brake under normal working conditions can be greatly reduced, thereby improving comfort. This control method is simple and easy to implement.

[0077] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present application, and in practical applications, various changes may be made to the embodiments in form and detail without departing from the spirit and scope of the present application. Any person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present application, and therefore the scope of protection of the present application shall be subject to the scope defined in the claims.

Claims

1. A power supply circuit, characterized in that: Used to supply power to the brake coil; the power supply circuit includes: an AC source module, a first switch module, an AC / DC conversion module, a voltage conversion module, a freewheeling module, a second switch module and an energy absorption module; The first switch module and the AC / DC conversion module are arranged in series between the first end and the second end of the AC source module; the two input ends of the voltage conversion module are electrically connected to the positive electrode and the negative electrode of the AC / DC conversion module respectively; the freewheeling module, the second switch module and the energy absorption module are arranged in series between the positive electrode and the negative electrode of the voltage conversion module in sequence; the brake coil is arranged in parallel with the energy absorption module; The AC source module is used to provide an AC signal to the AC-DC conversion module; the first switch module is used to remain disconnected during the release period of the brake and remain closed during the lifting period of the brake; the AC-DC conversion module is used to convert the AC signal output by the AC source module into a first DC signal during the lifting period of the brake; the voltage conversion module is used to convert the first DC signal output by the AC-DC conversion module into a second DC signal during the lifting period of the brake, wherein the voltage value of the second DC signal is different from that of the first DC signal; The second switch module is used to remain open in a first period of time within the release cycle of the brake, and remain closed in other periods except the first period of time, wherein the first period of time is any period of time within the release cycle of the brake; The freewheeling module is used to form a freewheeling loop with the second switch module, the brake coil and the voltage conversion module when the second switch module remains closed; The energy absorption module is used to absorb the energy released by the brake coil when the second switch module remains disconnected.

2. The power supply circuit according to claim 1, characterized in that: A starting time of the first period is greater than a starting time of a release period of the brake, and an ending time of the first period is less than an ending time of the release period of the brake.

3. The power supply circuit according to claim 2, characterized in that: The duration of the first period is the time required for the energy absorption module to absorb a preset energy value, and the percentage range of the preset energy value to the energy value released by the brake coil is [40%, 80%].

4. The power supply circuit according to claim 1, characterized in that: The start time of the first period is greater than the start time of the release period of the brake, and the end time of the first period is equal to the end time of the release period of the brake.

5. The power supply circuit according to any one of claims 1 to 4, characterized in that: The voltage conversion module includes a transformer, the second switch module includes a first MOS tube or a first crystal triode, the freewheeling module includes a first crystal diode, and the energy absorption module includes a voltage regulator tube and a second crystal diode connected in series; The two ends of the primary coil of the transformer are electrically connected to the positive and negative electrodes of the AC / DC conversion module respectively, the positive electrode of the secondary coil of the transformer is electrically connected to the positive electrode of the first crystal diode, the negative electrode of the first crystal diode is electrically connected to the first end of the first MOS tube or the first crystal triode, the second end of the first MOS tube or the first crystal triode is electrically connected to the positive electrode of the voltage regulator tube, the negative electrode of the voltage regulator tube is electrically connected to the negative electrode of the second crystal diode, the positive electrode of the second crystal diode is electrically connected to the negative electrode of the secondary coil of the transformer, one end of the brake coil is electrically connected to the positive electrode of the voltage regulator tube, and the other end is electrically connected to the positive electrode of the second crystal diode.

6. The power supply 2 circuit according to claim 5, characterized in that: The power supply circuit further includes a first capacitor, one end of which is electrically connected to the cathode of the first crystal diode, and the other end of which is electrically connected to the cathode of the secondary coil of the transformer.

7. The power supply circuit according to claim 6, characterized in that: The AC source module includes an AC source, the first switch module includes a first group of contact switches and a second group of contact switches, both groups of contact switches include a contact switch of a first relay and a contact switch of a second relay connected in series, and the AC-DC conversion module includes a rectifier; The first end of the AC source, the first group of contact switches and the first input end of the rectifier are electrically connected in sequence, and the second end of the AC source, the second group of contact switches and the second input end of the rectifier are electrically connected in sequence.

8. The power supply circuit according to claim 7, characterized in that: The power supply circuit also includes a resistor, a second capacitor and a second MOS tube or a second transistor; One end of the resistor is electrically connected to the positive electrode of the rectifier, and the other end is electrically connected to the first end of the primary coil of the transformer; the first end of the second MOS tube or the second transistor is electrically connected to the second end of the primary coil of the transformer; the second end of the second MOS tube or the second transistor is electrically connected to the negative electrode of the rectifier; one end of the second capacitor is electrically connected to the negative electrode of the rectifier, and the other end is electrically connected to the first end of the primary coil of the transformer.

9. An electronic device, characterized in that: The invention comprises a brake coil and a power supply circuit as claimed in any one of claims 1 to 8.

10. A control method for a power supply circuit according to any one of claims 1 to 8, characterized in that: include: During the release cycle of the brake, the first switch module controlling the power circuit remains disconnected, and the second switch module controlling the power circuit remains disconnected during the first time period during the release cycle of the brake and remains closed during other time periods except the first time period, wherein the first time period is any time period within the release cycle of the brake.

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