93results about How to "Implement overvoltage protection" patented technology

The invention relates to a high-temperature press sensor of silicon-silicon-bonded-based silicon on an insulator (SOI) and a producing method, belonging to the field of sensor chip, characterized in that a shallow slot and a gas vent on a support silicon substrate are all formed through anisotropic etch; suitable depth of the shallow slot can be obtained by controlling etching time so as to accomplish over-voltage protection for the device; the support silicon substrate is bonded with an inverted SOI chip; a piezoresistor is produced on the top layer of silicon after reducing and polishing the back of the SOI chip. The device can operate normally at high temperature using SOI buried oxide layer for isolation of sensitive component and elastic component.

The invention discloses a multiple output supply, comprising a transformer provided with at least two output paths, a power control module for controlling the input of the transformer, and a voltage detecting comparison module. The voltage detecting comparison module detects an output voltage of a certain output path in a plurality of output paths except a main output path provided with feedback, and outputs the detecting result to the power control module; the power control module can start up the protection according to the detecting result. The invention further comprises a mutual-inductance element, wherein the mutual-inductance element is in series connected to a detecting output path which is connected with a voltage detecting module and at least one output path of the multiple output supply respectively. The circuit of the invention is very simple, complicated circuits, such as reference source and comparator, are not needed, and the parts that can bring depletion such as resistance are not required.

The invention relates to a pressure sensor chip based on silicon direction bonding and silicon on insulator and a manufacturing method thereof, and belongs to the field of sensor chips. The invention is characterized in that a shallow slot and a gas port on a supporting silicon wafer are formed through anisotropy corrosion, and appropriate shallow slot depth obtained by controlling the corrosion time can realize over pressure protection of parts. A silicon direct bonding technology bonds the supporting wafer and a reversed SOI wafer, realizes a beam-membrane structure on the SOI after lapping and polishing to improve the sensitivity and linearity of the parts; manufactures force sensing resistance elements on the processed beam; adopts the oxidation buried layer of the SOI to solve insulation and isolation of the sensing elements and elastic elements; and improves the long-termed reliability and adaptability under high temperature of the parts. The SOP high-sensitivity pressure sensor chip based on the bonding technology has the advantages of controllable process, excellent repeatability and high finished product rate.

The invention discloses an overvoltage protection circuit for an integrated circuit, which comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a PMOS transistor, a first NMOS transistor, a second NMOS transistor, a comparator and a plurality of zener diodes, wherein all the zener diodes are connected by connecting the negative electrode with the positive electrode sequentially; the overvoltage protection of the integrated circuit and the clamping and electrostatic discharge protection of an input power can be easily realized by selecting appropriate zener voltage and number of the zener diodes and the resistance valves of the first, second and third resistors; and the second NMOS transistor and the fifth resistor constitute an effective input power electrostatic discharge protection circuit; therefore, additional electrostatic discharge protection circuits are not required to monitor the overvoltage condition of the input power, and the complexity of the integrated circuit is greatly reduced; in addition, the overvoltage protection circuit can be applied to other systems besides an electronic power system, so the overvoltage protection circuit has wide application.

The invention discloses an output voltage isolation sampling circuit of a high-voltage inverter. The isolation sampling circuit is composed of a resistor and divider sampling circuit, a differential amplifier conditioning circuit, an optocoupler isolation sampling circuit, and an operational amplifier conditioning circuit. The input terminal of the resistor and divider sampling circuit is connected with a voltage output terminal of a high-voltage inverter; the differential amplifier conditioning circuit is connected with the resistor and divider sampling circuit electrically; and the operational amplifier conditioning circuit is connected with the optocoupler isolation sampling circuit electrically. The voltage after processing is a voltage meeting a digital-analog signal converter sampling pin of a digital signal processing chip and is sent into a digital-analog signal converter sampling pin of a digital signal processing chip; and the digital signal processing chip carries out sampling and computing processing, so that the system is controlled to monitor the output voltage of the high-voltage inverter in real time and overvoltage protection, undervoltage protection, phase-locked bypass and other functions can be realized.

The invention provides an overvoltage protective circuit in an LED driving power supply without an auxiliary winding. A sampling and holding unit detects a voltage Vcs flowing through a current sampling resistor of the driving power supply; a time detection unit detects conduction time of a secondary side diode of the driving power supply, and the conduction time is utilized to generate a voltage Vref via a current source and a charging capacitor; when the conduction time of the secondary side diode ends, a first comparator compares the voltage Vref and the voltage Vcs, and when the voltage Vref is less than the voltage Vcs, the first comparator outputs an overvoltage signal to a control logic unit; the control logic unit outputs a switching signal to a switching driving unit according to the overvoltage signal; and the switching driving unit turns off a power tube of the driving power supply according to the received switching signal. An independent transformer winding is not needed in detection of the output voltage, and detection of a pin bit is also not needed so that the manufactured LED driving power supply is smaller in volume and lower in cost.

The invention discloses an input voltage overvoltage protection circuit which comprises a zero crossing detection module, an overvoltage detection module, a protection control module and a switcher. The zero crossing detection module is used for detecting whether the input voltage provided by an alternating current power source is in a zero crossing time frame or not. The overvoltage detection module is used for detecting whether overvoltage occurs in the input voltage provided by the alternating current power source or not. The protection control module is used for controlling the switcher to be disconnected when overvoltage occurs in the input voltage and controlling the switcher to return to the breakover state when overvoltage does not occur in the input voltage and the input voltage is in the zero crossing time frame. According to the protection circuit, when overvoltage occurs in the input voltage, the switcher is controlled to be disconnected, and the switcher is controlled to be in the breakover state again when overvoltage does not occur in the input voltage and the input voltage is in the zero crossing time frame; due to the fact that when the switcher is in the breakover state again, and the input voltage is in the zero crossing time frame, the situation that when the switcher resets again, the circuit is damaged due to excessively high input voltage is avoided, and the overvoltage protection of the input voltage can be achieved safely and effectively accordingly.

The invention discloses an overvoltage protection circuit and a switching power supply. The circuit receives an external sampling signal through an overvoltage detection module, and receives an external AC signal through an input module. When the voltage of the sampling signal is less than or equal to a preset threshold value, the overvoltage detection module controls a switching module to be in aconnected state, and an output module outputs a power supply signal. When the voltage of the sampling signal is greater than the threshold value, the overvoltage detection module controls the switching module to be in a disconnected state, and the output module stops the outputting of the power supply signal. The switching power supply comprises the overvoltage protection circuit, a power management circuit and an AC-DC conversion circuit. The AC-DC conversion circuit is used for converting the connected commercial power into a direct current for supplying power to power utilization equipment. The power management circuit is used for controlling the working state of the AC-DC conversion circuit according to the power supply signal outputted by the overvoltage protection circuit. The overvoltage protection circuit achieves the overvoltage protection of the circuit, and protects the overvoltage from causing damages to circuit elements.

The invention discloses a power supply for a direct current (DC) 600V train power supply device control unit. The power supply is characterized by comprising a DC110V input end, an input protection circuit connected with the DC110V input end, an input filter circuit connected with the input protection circuit, a DC-DC conversion circuit connected with the input filter circuit, an output filter circuit connected with the DC-DC conversion circuit, an output state indication circuit connected with the output filter circuit and an output end connected with the output state indication circuit. The power supply is simple in structure and strong in surge resistance and can effectively restrain interference and output power stably; the safe and reliable power supply is provided for the control unit of a DC 600V train power supply device, production cost of the DC 600V train power supply device is reduced to some extent, and the power supply not only is convenient to produce, but also is extremely low in cost and suitable for being widely popularized.

The aim of the invention is to design a cooling appliance, in particular a combined household refrigerator / freezer which has a simple structure and in which each of at least two compartments can be individually switched off. Said aim is achieved by a cooling appliance comprising a cooling cycle that encompasses a compressor (5), a condenser (6) with a cooling conduit (60) that is connected to the compressor (5) at the first end (61), a first valve (11) that is connected to the second end (62) of the cooling conduit (60) of the condenser (6), a first evaporator (3) that is arranged downstream of the first valve (11) and is connected to the compressor (5), and a second evaporator (4). A second valve (10) is arranged between the two ends (61, 62) of the cooling cycle (60) of the condenser (6) and is connected to the second evaporator (4) by means of a second outlet (10b). The second evaporator (4) is connected to the compressor (5) at the outlet end. It is thus advantageously possible to design a simple dual cycle system comprising a single compressor while the amount of coolant can be adjusted to the condenser, or vice versa, because coolant is stored in the second portion (6b) of the condenser (6), resulting in greater energy efficiency.

The invention relates to a novel explosion-prevention thin film capacitor, belonging to the field of a capacitor. A "serial-parallel" connection mode is adopted between winding cores, and thus, the influence of winding core breakdown to the capacitor is reduced; energy storage is low by connecting a bypass component in series, and adjacent winding cores are difficult to be damaged during winding core breakdown or a shell is insulated; the heat exchange effect is improved by using heat conduction epoxy resin, heat conduction oil and an arc concave surface, and fault expansion or shell explosion is favorably prevented; with the arrangement of an overvoltage current-limiting device, breakdown caused by too high current in a bypass component circuit is effectively avoided to burn the circuit or explode, and the current and the voltage in the bypass component are ensured to be continuously stable; and with the arrangement of an overvoltage protection device, an electrical component is prevented from impact of overvoltage and high voltage. The capacitor has the advantages of compact structure, low overall loss and low cost, the installation space is saved, the running fault rate is reduced, the quality defect is favorably reduced, and the electrical component is high in capacitor, few in winding core number, high in production efficiency and good in explosion performance.

The invention discloses a main board protection circuit. The main board protection circuit comprises an overvoltage protection circuit, a slow-start protection circuit and a switch control circuit. By implementing the main board protection circuit disclosed by the invention, the following beneficial effects are achieved: overvoltage protection for the main board of a computer can be realized, and the damages of wrong plugging of an adapter to the main board are prevented; the damages of an instantaneous voltage surge of plugging the power supply adapter to the main board are avoided by virtue of the slow-start protection circuit and the switch control circuit; the circuit is simple and the cost is low.

The invention discloses an embedded ultrasonic motor drive controller, and the controller comprises an external clock, a microcontroller module, a power amplification and matching module, a position sensor interface module, a motion control card interface module, a circuit protection module, a display interface module, a communication interface module and a power conversion unit module, wherein the external clock provides a time reference for the microcontroller module. A signal generated by the microcontroller module is used for driving a to-be-controlled ultrasonic motor. The position sensor interface module collects position information, and feeds back the position information to the microcontroller module. The motion control card interface module supplies an enabling signal, a position instruction signal and a speed instruction signal to the microcontroller module. The circuit protection module provides a function of motor connection protection and functions of overheating, overvoltage, undervoltage and overcurrent protection. The display interface module and the communication module provide man-machine interaction windows for a drive controller. The drive controller is good in universality, is diversified in control parameters, is easy for the integration of a plurality of control modes, and facilitates the implement of high-precision control of an ultrasonic motor.

The invention proposes a separation and falling connector assembly with a photoelectric conversion function. A photoelectric conversion technology is employed, connection of optical signals of two ends of a separation and falling connector plug assembly and a separation and falling connector socket assembly is achieved, the optical signal of one end of the connector is converted to an electrical signal, the electrical signal passes through an insertion surface of the connector by a high-speed electrical contact piece, the electrical signal passing through the insertion surface is converted to an optical signal, and the optical signal is output. A ceramic contact piece can be prevented from being used, the problem that a fiber contact piece is easy to pollute and damage is prevented, daily application and operation specification of an electrical connector can be followed, high usability is achieved, special instrument equipment is not needed to check cleanness of an end surface of a connector ceramic insertion core and completeness of a ceramic sleeve, and the application is greatly facilitated.

The invention discloses a charging circuit which comprises a power supply module, a control module and an overvoltage protection module, wherein the power supply module is used for charging a charged battery; the control module is used for controlling the power supply module to perform first-stage charging on the charged battery according to a pre-configured constant current parameter, and is also used for controlling the power supply module to perform second-stage charging on the charged battery according to a pre-configured constant voltage parameter after voltage for first-stage charging is compared with pre-configured voltage; and the overvoltage protection module is used for disconnecting the charging loop between the power supply module and the charged battery when the charging time of second-stage charging reaches preset charging time. According to the invention, the overvoltage protection module disconnects the charging loop between the power supply module and the charged battery when the charged battery is charged for preset charging time, thereby preventing the charged battery from being damaged due to overcharging, and improving the service performance and service life of the charged battery.

The invention relates to a switch module, a converter and an electrical energy conversion device. The switch module comprises at least two electronic switches and at least two overvoltage protection circuits, wherein the electronic switches are serially connected to one another; the overvoltage protection circuits are electrically coupled to the electronic switches respectively; each overvoltage protection circuit comprises a clamping unit and a protecting unit; each clamping unit is used for providing a clamping voltage to the corresponding electronic switch when voltages at two ends of the corresponding electronic switch are greater than a first preset voltage; and each protecting unit is used for switching on the corresponding electronic switch when the voltages at two ends of the corresponding electronic switch are greater than a second preset voltage. Each electronic switch can be subjected to double overvoltage protection by the corresponding clamping unit and the corresponding protecting unit, and the reliability is improved. The invention also provides a converter comprising the switch module and an electrical energy conversion device comprising the switch module.

The invention provides an overvoltage protection circuit, which comprises an overvoltage protection chip and a charging chip. The overvoltage protection chip compares the voltage of a voltage detection pin with a reference voltage; when the voltage of the voltage detection pin is lower than the reference voltage, the overvoltage protection chip enables the charging chip, so that the charging chip is driven to charge a high voltage battery; and when the voltage of the voltage detection pin equals to or is greater than the reference voltage, the overvoltage protection chip stops enabling the charging chip, so that the charging chip stops charging the high voltage battery. Once the overvoltage protection circuit of the invention detects that the charging voltage of the high voltage battery exceeds the maximal voltage thereof, enablement for the charging chip is stopped immediately, so that charging for the high voltage battery is stopped, and overvoltage protection for the high voltage battery is further realized.

The invention provides a protection circuit of a storage capacitor, and relates to the electricity field. The protection circuit is used for solving the protection problem of a high-capacity storage capacitor, and comprises a rectifying circuit and the storage capacitor, wherein the rectifying circuit is connected with an alternating current (AC) input end; the storage capacitor is connected with an direct current (DC) output end; an overvoltage protection circuit for the storage capacitor is connected between the rectifying circuit and the storage capacitor in parallel and comprises a relay with a normally open contact and a normally closed contact, a first voltage-regulator diode, a second voltage-regulator diode and a current-limiting resistor; the normally closed contact of the relay is connected between the output of the rectifying circuit and the positive pole of the storage capacitor in series; the normally open contact of the relay is connected with a circuit in series, and the circuit comprises the current-limiting resistor and the second voltage-regulator diode; the first voltage-regulator diode is connected with a circuit in parallel, and the circuit comprises the current-limiting resistor and the normally open contact of the relay; the positive pole of the second voltage-regulator diode is connected with the current-limiting resistor and the negative pole of the first voltage-regulator diode; and the negative pole is connected with the positive pole of the storage capacitor. The protection circuit can realize the overvoltage protection for the storage capacitor.

The invention relates to a capacitance buck-type LED driver and a capacitance buck-type LED driving method thereof. The capacitance buck-type LED driver comprises a control circuit and a switch circuit, wherein the control circuit controls an on-off state of the switch circuit according to output current and the output voltage of the capacitance buck-type LED driver so as to control values of energy transferred from the input side to the output side. In a first working state, the switch circuit controls the input side not to transfer the energy to the output side; and in a second working state, the switch circuit controls the input side to transfer the energy to the output side so as to the keep output current and expected driving current to be consistent.

The invention discloses an intelligent aging rack. The intelligent aging rack comprises a control instrument, a control box and an aging rack body. The control instrument comprises an MCU control module, an indication module, a display module, a PTT signal control module, a warning module, a key module, a control instrument power supply module and a control instrument cable socket, wherein the indication module, the display module, the PTT signal control module, the warning module, the key module and the control instrument power supply module are connected with the MCU control module, the control instrument power supply is used for supplying power, and the control instrument cable socket is connected with the PTT signal control module. The control box comprises a control circuit board, a relay, a PTT signal interface, a PTT signal indicator lamp, a control box power supply module and a control box cable socket, wherein the relay, the PTT signal interface, the PTT signal indicator lamp, the control box power supply module and the control box cable socket are connected with the control circuit board, and the control box power supply module is used for supplying power. The aging rack body comprises a frame, a power supply and a PTT signal control interface, wherein the frame is used for containing aging products, the power supply is used for supplying power to the aging products, and the PTT signal control interface is used for conducting control signal output on the aging products. The intelligent aging rack is compact in structure, safe, reliable, low in cost, capable of achieving dynamic aging by simulating the actual working state of the aging products, capable of monitoring aging process parameters and beneficial for batched aging process.

The invention discloses an input overvoltage protection circuit. The circuit is capable of monitoring the size of DC voltage after the rectification of AC input voltage in real time and controlling the on / off of a switching element in a chopper circuits through a sampling circuit. When the AC input voltage is abnormally high, the sampling circuit is capable of rapidly detecting and controlling theswitching element in the chopper circuit to be located in an on / off state and freely setting an on overvoltage protection threshold value and an off overvoltage protection threshold value to maintainthe voltage size of an energy storage capacitor, so as to rapidly and effectively protecting a post circuit, prevent an energy storage capacitor and a switch tube in the post circuit from being damaged by overvoltage and enable the post circuit to continue the normal work. The input overvoltage protection circuit is suitable for the condition or occasion of three-phase four-wire AC voltage inputor single-phase AC voltage input which possibly has grounding faults to cause abnormal overvoltage of power grids, is high in reaction speed, simple and reliable in circuit, low in cost, excellent inEMC performance and flexible in design, and is capable of adjusting the on overvoltage protection threshold value and the off overvoltage protection threshold value.

The invention relates to a retired battery module adopting flexible connection protection, and is used for realizing differentiated retired battery module grouping and realizing echelon battery utilization. The battery module flexible connection module is provided with an execution and monitoring unit and can detect and upload voltage and temperature of a battery and a module. In the charging anddischarging process of the battery, when the voltage of the battery exceeds the normal working voltage range of the battery, the battery is withdrawn to protect the battery, and differentiated retiredbattery modules are grouped and echelon battery utilization is realized through a uniform charging control function. The invention further relates to a battery pack. The battery pack is formed by sequentially connecting a plurality of battery modules in series through the battery module flexible connection device.

The invention discloses an overvoltage protection method and device, and a modular multilevel converter valve. The method specifically comprises the steps of: obtaining a capacitor voltage of each sub-module, and calculating the average capacitor voltage of all sub-modules on each bridge arm according to all capacitor voltages; if a converter valve is in an unlocked state, determining whether overvoltage occurs in the sub-module or not according to whether the capacitor voltage exceeds a first preset protection constant value or not; if the sum of the number of the sub-modules with the overvoltage and the number of the bypassed sub-modules is greater than the number of the redundant modules, locking the converter valve and performing tripping; and if the sum is smaller than or equal to thenumber of the redundant modules, locking and bypassing the sub-modules with the overvoltage; if the converter valve is in a locked state, and if the average capacitor voltage of the sub-module of anybridge arm is greater than a preset value, bypassing the sub-module of which the capacitor voltage is greater than a second preset protection constant value; and if the average capacitor voltage of the sub-module of any bridge arm is less than a preset value, bypassing the sub-module of which the capacitor voltage is greater than a third preset protection constant value. Through the above operation, overvoltage protection of the sub-modules is achieved.

The invention discloses an air conditioner overvoltage detection circuit, an air conditioner electric control device and an air conditioner. The air conditioner overvoltage detection circuit includesa first AC input end, a second AC input end, a rectifier circuit, a resistor voltage divider circuit, a voltage reference chip and an optocoupler feedback circuit. When an AC voltage is an overvoltage, a reference pole voltage of the voltage reference chip is greater than internal reference voltage, the voltage reference chip is turned on, the optocoupler feedback circuit is controlled for outputting an overvoltage feedback signal to a processor of the air conditioner or a controller in a power circuit of the air conditioner, in turn, the power input is correspondingly cut off to achieve overvoltage protection. The air conditioner overvoltage detection circuit is advantaged in that voltage detection is implemented by using a preset reference voltage inside the voltage reference chip, a current value flowing through the resistor divider circuit is small, the power consumed by the resistor voltage divider circuit is milliwatts, and thereby loss and cost are reduced.

The invention discloses an automatic flow regulating device for airborne oxygen production equipment. The automatic flow regulating device comprises a housing, a lung type valve component, a rocker arm component and a film assembly, wherein an oxygen inlet connected with an oxygen production system and a mask air intake duct communicating with a breathing mask are arranged on the housing; an air intake cavity, an air storage cavity and a balancing cavity are arranged in the housing; the air intake cavity communicates with the mask air intake duct; the air intake cavity communicates with the air storage cavity via the lung type valve component; the lung type valve component communicates with the oxygen inlet; the air storage cavity is separated from the balancing cavity via the film assembly; and transmission between the film assembly and the lung type valve component is realized through the rocker arm component. According to the automatic flow regulating device, a pressure difference between the air storage cavity and the balancing cavity is sensed by the film assembly, and the intake of oxygen is controlled and regulated by the rocker arm component and the lung type valve component, so that the function of automatic flow regulation is realized; and the functions of automatic pressure regulation, overpressure protection, excess pressure stabilization, asphyxiation prevention and the like are realized by a corrugated pipe component, an excess pressure valve component, an air valve component and the like.

The invention discloses a remote control device for removing snow and dust by using compressed air and a control method thereof. The device comprises an air compressor, an air storage tank, an air delivery pipe and a remote control system, wherein the remote control system simultaneously controls the work of the air compressor and the opening / closing of the air delivery pipe. The control method comprises the following steps of: extracting a pressure value of high-pressure air by using a pressure controller, controlling the on / off of a circuit by using pressure and simultaneously realizing the opening and closing of a vent pipe by using an electromagnetic valve. The device and the method provided by the invention have the advantages of fulfilling the aim of removing the snow and the dust by utilizing the compressed air and simultaneously achieving the effect of unmanned field operation.

The invention discloses an automobile sensor protection circuit, which comprises an overvoltage control unit, a switch unit and an anti-reverse-connection unit, wherein the overvoltage control unit is connected among a power source power supplying end, a load grounding end and a control end of the switch unit, an input end of the switch unit is connected with the power source power supplying end, an output end of the switch unit is connected with a load power receiving end, the overvoltage control unit controls the on-off state of the switch unit according to the voltage change of the power source power supplying end, the anti-reverse-connection unit is connected among the power source power supplying end, a power source grounding end and a load grounding end, so that the damage to a load caused by the reverse connection of a power source and the load or negative voltage pulse can be avoided. The automobile sensor protection circuit has the advantages that the overvoltage protection and the reverse connection protection on an automobile sensor are realized, and the fault rate of the automobile sensor is reduced.

The invention discloses a self-powered Internet of Things chip overvoltage protection circuit which comprises a switching circuit bias voltage generation circuit which is connected with an energy acquisition circuit and a switching circuit and used for generating bias control voltage required for switching on the switching circuit; the switching circuit which is connected with the energy acquisition circuit and an Internet of Things chip system, and is used for forming a conduction path with variable equivalent resistance between the output of the energy acquisition circuit and the Internet ofThings chip system under the control of the bias control voltage generated by the bias voltage generation circuit of the switching circuit so as to form a variable voltage drop; and a bleeder circuitwhich is connected with the output end of the switching circuit and the switching circuit bias voltage generation circuit so as to form a bleeder branch when the output voltage is relatively high andinfluence the bias control voltage output by the switching circuit bias voltage generation circuit in proportion.

The invention discloses a CT power taking-based power taking device and method employing an overhead lightning protection ground wire of a power transmission line. The power taking device comprises power taking cores, wherein the power taking cores are connected with an overvoltage protection unit; the overvoltage protection unit is connected with a power voltage stabilizing unit; a power monitoring unit is connected with an output end of the overvoltage protection unit; one power taking core L1 is arranged on each of two sides of left and right ground wire hanging points of each iron tower; and the output end of each power taking core L1 is connected with an input end of the overvoltage protection unit through an insulating cable. Power is obtained through the annular power taking cores on an alternating magnetic field generated around the overhead ground wire by using induced current on the overhead ground wire; a plurality of power taking cores can be connected in parallel at the same time to improve the total power taking efficiency of the power taking device; meanwhile, overvoltage protection of input voltage is achieved by adopting a switch-type short circuiting device in a power supply; the whole work efficiency and the security of the power taking device are improved; and the disadvantages of the prior art are avoided.

The invention discloses a switching power supply control device and control method and a switching power supply system. The control device comprises a generation module which is used for generating overvoltage protection signals when the output voltage of the secondary side of a switching power supply is greater than a preset first voltage threshold; and a control module which is used for controlling the driving control circuit of the primary side of the switching power supply according to the overvoltage protection signals so that the switching power supply is enabled to restart. According to the control device and the control method, the error caused by the influence of the transformer and the feedback branch in the primary sampling mode can be avoided so that overvoltage protection of the switching power supply can be more accurately realized.