66 results about "Lightning surges" patented technology

The invention discloses an information acquisition and transmission system of track control equipment, which relates to the technical field of track traffic intelligent monitoring and comprises an intelligent sensing terminal, an edge intelligent analysis node, a safety communication module, a central control platform, a digital twin diagnosis center and a predictive maintenance engine. According to the invention, the intelligent sensing terminal integrates various sensors, adopts a permalloy shielding cavity to isolate external electromagnetic interference, is equipped with a three-stage lightning protection circuit to realize microsecond-stage lightning surge protection, can stably collect parameters of track control equipment in a severe environment, is internally provided with a lightweight LSTM model, carries out preliminary filtering analysis on original data, and is used for monitoring the parameters of the track control equipment. The device operation state can be dynamically identified, the sampling strategy can be adjusted, the basic sampling frequency is maintained in the stable state to reduce power consumption, the sampling frequency is improved by 10 times and the sensor gain is enhanced in the early warning or emergency state, all analysis decisions are completed at the local millisecond level without depending on the cloud, and the real-time performance and accuracy of data processing are effectively improved.

The invention relates to the technical field of multi-column lightning arresters, in particular to a multi-column lightning arrester parallel matching method, which comprises the following steps of S1, performing aging screening and energy tolerance testing on zinc oxide resistor discs of the same batch; s2, measuring the direct-current reference voltage Uref of the resistor discs, the leakage current I0 under 0.75 Uref, the impact residual voltage UL under the lightning wave and the operation residual voltage US under the operation wave one by one; s3, screening the resistor discs for three times; and S4, high-low matching is carried out by taking the operation residual voltage US as a main matching basis, so that the operation residual voltage deviation of each column of series resistor disc group is smaller than a first preset value, and the direct current reference voltage numerical value deviation is smaller than a second preset value. The strict screening process ensures the consistency of the performance of the resistor discs, and the reasonable grouping mode makes the electrical performance of each column resistor disc group more balanced, thereby achieving the effect of improving the operating wave endurance capability and the current sharing characteristic of the multi-column lightning arrester, and reducing the probability of faults caused by uneven current distribution of the MOV.

The invention relates to the technical field of SPD lightning protection, in particular to an intelligent SPD lightning protection detection system. The system comprises a data acquisition module used for acquiring leakage current, voltage and temperature of a piezoresistor; the lightning protection analysis module is used for analyzing the dispersion degree of the leakage current of the piezoresistor and the change trend of the leakage current, and determining the damage degree of the piezoresistor in combination with the temperature range of the piezoresistor and the dispersion degree of all elements in the leakage current coupling sequence; the method comprises the following steps of: analyzing the complexity and the voltage change trend of abrupt change data in the voltage of the varistors, and combining the similarity of the voltage change trends between the varistors connected in parallel to determine the voltage anomaly of the varistors; and the lightning protection detection module is used for judging the lightning protection detection precision at the current moment. According to the invention, the problem that the SPD lightning protection detection system cannot prevent lightning surge and power frequency voltage from damaging electrical equipment is solved, and the reliability of the SPD lightning protection detection system is improved.

The invention relates to the field of explosion-proof electrical technology, and discloses an intrinsically safe output Ethernet transmission circuit, which comprises an Ethernet physical layer transceiver chip U6, a network transformer U7, an electrostatic protection diode D17, an electrostatic protection diode D18, voltage stabilizing diodes D13-16, capacitors C46-62, resistors R42-45, resistors R59-65, thick film resistors R74-77, fuses F1-4, a safety Y capacitor CY1, an inductor L2, a gas discharge tube TV1, a gas discharge tube TV2 and an RJ45 connector RJ1. The intrinsically safe output Ethernet transmission circuit provided by the invention realizes 3000V voltage isolation, has the characteristics of low cost and easiness in implementation, not only has strong anti-interference and lightning surge protection capabilities and stable transmission performance, but also is easy to calculate and check intrinsically safe parameters through multi-stage isolation and current-limiting and voltage-limiting protection, and has a wide application prospect. And multiple key problems in intrinsic safety Ethernet transmission are effectively solved.

The utility model discloses a lightning surge counting and monitoring device with a remote data uploading function. The lightning surge counting and monitoring device comprises a main control circuit board, a display control circuit board and a display module which are packaged in an outer shell, the display control circuit board is electrically connected to the main control circuit board; the display module is electrically connected to the display control circuit board and is exposed from the upper surface of the outer shell; the first end of the main control circuit board is provided with a power supply wiring terminal and a sensor wiring terminal, and the second end of the main control circuit board is provided with a communication wiring terminal. The device can record the number of lightning strokes and display the number of lightning strokes through the display module, and can also upload the number of lightning strokes, time and other data to a maintenance platform in a remote communication mode, so that maintenance personnel can know the state of the system in time. Maintenance personnel can assess and maintain the damage degree of the lightning surge protection device conveniently, the safety of an electric power system can be improved, and the risk assessment capability of the electric power system is enhanced.

The present invention discloses a transmission tower line simulation method, apparatus, device, and storage medium. A partial element equivalent circuit method is used to establish a partial element equivalent circuit model for a first subsystem consisting of a lightning channel, a tower, and overhead line segments directly connected to the tower. A one-dimensional time-domain finite difference method is used to establish a multi-conductor transmission line model for a second subsystem consisting of overhead line segments not directly connected to the tower. Interface node analysis equations are established between the first and second subsystems to jointly solve for the node voltages and branch currents of a high-voltage overhead transmission line system with a grounding wire. This method addresses the technical problems of large errors in tower surge assessments caused by traditional transmission tower models that fail to consider the mutual coupling between the lightning channel, tower, and transmission line, and inaccurate analysis of lightning surge impacts caused by the TEM-based MTL model's inability to accurately capture the true propagation behavior of electromagnetic waves on transmission line towers during lightning strikes.

This application relates to the field of multi-column surge arrester technology, and in particular to a method for parallel connection and grouping of multi-column surge arresters, comprising the following steps: S1, performing aging screening and energy withstand tests on zinc oxide resistors of the same batch; S2, measuring the DC reference voltage U of each resistor. ref 0.75U ref Leakage current I0 under lightning surge, residual voltage U under lightning surge L and the residual operating voltage U under the operating wave S S3, select resistors in three stages; S4, operate the residual voltage U S The primary basis for grouping is a combination of high and low voltage resistors, ensuring that the residual voltage deviation of each series-connected resistor group is less than a first preset value and the DC reference voltage deviation is less than a second preset value. This rigorous selection process guarantees the consistency of resistor performance, and the reasonable grouping method makes the electrical performance of each resistor group more balanced. This improves the operating waveform withstand capability and current sharing characteristics of the multi-column surge arrester, reducing the probability of MOV failure due to uneven current distribution.

Embodiments of the present application relate to the field of circuit, and disclose a lightning protection circuit, a circuit board assembly and an electronic device. In the present application, the conduction states of the first switch and the second switch are determined according to the voltage of the first end of the first switch and the voltage of the second end of the second switch, but the conduction states of the first switch and the second switch must be opposite, and when the first switch is on and the second switch is off, the second polarity capacitor works; when the first switch is off and the second switch is on, the first polarity capacitor works; so that no matter which end of the lightning protection circuit receives a larger level of lightning surge, the residual voltage can be absorbed by a larger capacity polarity capacitor, thereby protecting the external circuit; since the polarity capacitor is used, the storage capacity is large, the number of capacitors to be set is small, the lightning protection level of the lightning protection circuit is improved at a small cost and a small circuit space.

The invention relates to the technical field of LED lamp manufacturing, and provides an anti-lightning surge driver light engine device in order to solve the technical problem that an existing small-size lamp product is insufficient in lightning surge resistance, the anti-lightning surge driver light engine device comprises an overcurrent protection circuit, an overvoltage protection circuit and an EMC circuit, the overcurrent protection circuit is connected to a phase line circuit in series, and the overvoltage protection circuit is connected to the EMC circuit in series. The power supply is cut off when current is abnormal; the overvoltage protection circuit is arranged between the phase line circuit and the zero line circuit and is used for absorbing transient overvoltage; the EMC circuit is arranged at the rear stage of overcurrent protection and is used for inhibiting electromagnetic interference; the overcurrent protection circuit comprises a first safety resistor, a second safety resistor, a first thermistor and a second thermistor, and the overvoltage protection circuit comprises a first piezoresistor which is connected between the first safety resistor and a zero line circuit; the second piezoresistor is connected between the second safety resistor and the zero line circuit; and the third piezoresistor is connected between the post-stage of the overcurrent protection circuit and the zero line circuit.

The application provides a surge test modeling method and terminal for an electrical system, which establishes a lightning surge interference source model, a device port and an impulse voltage conduction path model, a device insulation coordination model and a lightning protection device model, is used for simulating and testing the response behavior of lightning surge interference of a low-voltage electrical system, realizes process evaluation of lightning protection measures and lightning protection device selection of the system to analyze whether the lightning protection measures of the electrical system connected to a power distribution network are appropriate, whether main facilities and devices will be damaged after a lightning stroke, whether significant safety consequences will be caused and whether the selection of lightning protection devices is reasonable, avoids damage to the devices in actual tests, provides a basis for the design of lightning protection of the electrical system, and uses the principle of a controlled voltage source to establish a lightning protection device model of a surge protection device and make the voltage protection level parameter of the surge protection device output according to a current value, so that the voltage protection level parameter reaches the voltage resistance and clamping characteristics of the surge protection device when the surge protection device acts.

Embodiments of the present invention disclose a semiconductor discharge tube, a manufacturing method thereof, and an overvoltage protection device. Among them, the manufacturing method of the semiconductor discharge tube includes: in any device unit region of a semiconductor substrate, forming a first diffusion region and a second diffusion region of a second conductivity type separated by a body region of a first conductivity type on the semiconductor substrate; forming a groove on one side of the semiconductor substrate where the first diffusion region is provided; diffusing into the semiconductor substrate along the groove to form a third diffusion region of the first conductivity type, and the third diffusion regions are all in contact with the first diffusion region and the body region of the semiconductor substrate; forming a fourth diffusion region of the first conductivity type in the first diffusion region, and the third diffusion region and the fourth diffusion region are spaced apart; forming corresponding first conductive blocks, wherein the first conductive blocks are electrically connected to the first diffusion region and the fourth diffusion region. The technical solution provided by the embodiments of the present invention can reduce the residual voltage during lightning surges.

This invention discloses a surge protection circuit for gallium nitride (GaN) power devices in a power factor correction (PFC) circuit, aiming to solve the problems of insufficient surge resistance of GaN power devices and the high residual voltage of existing surge protection schemes, which easily leads to overvoltage breakdown of GaN power devices. A surge suppression unit is set between the rectifier circuit and the PFC main circuit. The surge suppression unit adopts a common-mode inductor containing a first coil L2A and a second coil L2B, coupled with a varistor VR4 in series, and is paired with capacitors C1 and C2 to form a π-type filter. Under normal operating conditions, it performs voltage filtering. During a lightning surge, VR4 breaks down, generating a surge current in L2A. The second coil L2B couples to generate a reverse electromotive force to offset the surge voltage, reducing the residual voltage at the input of the PFC main circuit. A primary protection unit assists in surge suppression. The PFC main circuit adopts a Boost topology and GaN power devices. This circuit has a simple structure, low cost, and high reliability, and is suitable for surge protection of outdoor GaN power supplies such as LED streetlights.

The invention discloses a lightning protection surge protection device based on household appliances, and belongs to the technical field of lightning protection. The protector main body is divided into two parts, the first part comprises an integrated plug and a leakage current protector, the second part is provided with an MOV surge protection module and an overvoltage and undervoltage module, and the two parts are connected through a cable and are adaptive to various household electric equipment. The protector is further integrated with a ground shortage detection module, a power output relay, a piezoresistor, a filtering module and a resistance-capacitance voltage reduction module, the response time of the MOV surge protection module reaches 25 ns, and lightning stroke current can be rapidly discharged; the overvoltage and undervoltage module is matched with a TL431 voltage reference device through an LM339 voltage comparison chip to realize overvoltage and undervoltage detection and power supply control; the ground lacking detection module is provided with a red light for indication to timely warn grounding hidden dangers. The lightning protection device can effectively reduce the damage of lightning stroke to personnel and equipment, deals with voltage fluctuation, and is simple and convenient to install and high in safety.

The invention discloses an intelligent lightning protection detection system, and belongs to the technical field of lightning protection detection. The system comprises a lightning protection grounding isolation device, a lightning protection counterattack box, a grounding resistance monitor, a surge monitor and a monitoring platform. The lightning protection grounding isolation device adopts an isolation type grouping grounding technology, realizes independent operation of working grounding, protection grounding and lightning protection grounding through a grounding isolation suppressor, and has multiple monitoring functions; the lightning protection counterattack box is connected in series between the signal ground or the working ground and the lightning protection grounding line, and discharges lightning surge in a directional manner; the grounding resistance monitor measures the resistance by using a precise three-wire method; the surge monitor collects lightning current parameters and records events; the monitoring platform manages data in a centralized manner, and provides real-time alarm, historical query and remote monitoring. The system improves the lightning protection effect, achieves the real-time comprehensive monitoring, is convenient in data management, is energy-saving and environment-friendly, and is high in compatibility.

The invention belongs to the technical field of equipment power utilization protection, and discloses a protection device and a protection method for preventing lightning stroke damage, and the protection device comprises an overvoltage protector which is connected with a power supply line, then is grounded, and is used for limiting transient overvoltage and discharging surge current; and the fuse is connected in series in a loop where the electric equipment is located and cuts off the loop where the electric equipment is located when the residual current exceeds the steady-state working current of the electric equipment, and the electric equipment takes the electric energy from the power supply line. According to the invention, electrical equipment can be effectively protected from being damaged by lightning surge current and residual current, long-term stable operation of the equipment is ensured, specifically, the current can be cut off in time through a quick response mechanism of the fuse, overload or short circuit of the equipment is avoided, and the safety and reliability of the equipment are improved.

To prevent a switching control section from being adversely affected even when a lightning surge is input to a low-voltage rated line. [Solution] The image forming device (1) includes a rectifying and smoothing circuit (112) that rectifies an AC voltage from which noise has been removed by a noise filter (Lc) and outputs the rectified voltage to a primary winding (L1) of a transformer (111); a switching control unit (121) that performs switching control; a power supply line (201) that is connected between the rectifying and smoothing circuit (112) and the primary side of the transformer (111) and inputs a high-voltage power supply voltage to a fourth terminal (VIN) of the switching control unit (121); a detection line (300) that is connected between the noise filter (Lc) and the rectifying and smoothing circuit (112), intersects with the power supply line (201), and inputs a low-voltage voltage to a fifth terminal (LS) of the switching control unit (121); and a first resistor (R10) that is connected between an intersection (500) of the detection line (300) with the power supply line (201) and a fifth terminal (LS) of the switching control unit (121) and drops the voltage input to the fifth terminal (LS).

This utility model discloses a high-reliability lightning surge protection circuit for a power distribution automation terminal, including an input discharge circuit, an AC rectifier circuit, and a filter circuit. The input discharge circuit includes Y capacitors C1, C2, and C3, as well as a relay K1, a varistor RV1, RV2, and RV3. The coil of relay K1 is connected between the positive terminal Vout and the negative terminal GND of the switching power supply output. This utility model not only meets the requirements for insulation strength testing and lightning surge testing, but also has the advantages of small size, low cost, and high reliability.

The utility model discloses a low-power-consumption lightning surge counting and monitoring device, which comprises a main control circuit board, a display module, a battery, an isolation acquisition circuit module and a lightning stroke current sensor, wherein the main control circuit board, the display module, the battery and the isolation acquisition circuit module are packaged in an outer shell; the display module, the battery and the isolation acquisition circuit module are respectively and electrically connected with the main control circuit board, the display module is arranged on the front surface of the main control circuit board and is exposed from the upper surface of the outer shell, the battery and the isolation acquisition circuit module are arranged on the rear surface of the main control circuit board, the main control circuit board is provided with a wiring terminal, and the wiring terminal is electrically connected with the main control circuit board. And the lightning stroke current sensor is electrically connected to the wiring terminal and is connected with external lightning protection equipment. The lightning surge protection device can record the number of lightning strokes and display the number of lightning strokes through the display module, so that maintenance personnel can conveniently evaluate and maintain the damage degree of the lightning surge protection device. Furthermore, the device adopts a low-power-consumption circuit design, and is particularly suitable for outdoor monitoring places or monitoring places where power supply is inconvenient.

The invention discloses a protection circuit for a dimming interface of a dimming power supply, which comprises overvoltage / overcurrent protection circuits respectively connected in series between a dimming signal external interface DIM + OUT and a dimming signal input end DIM + and between a dimming signal external interface DIM-OUT and a dimming signal input end DIM-, a clamping circuit and an anti-reverse connection circuit are respectively connected between the dimming signal input end DIM + and the dimming signal input end DIM-; the invention also discloses an implementation method of the protection circuit for the dimming interface of the dimming power supply. Voltage clamping is achieved through the voltage dependent resistor VR1, the temperature of the positive temperature coefficient thermistor RT1 rises rapidly, the resistance value of the positive temperature coefficient thermistor RT1 rises to the megohm level, connection between an abnormal signal and the dimming signal input end is cut off, a dimming interface is effectively prevented from being damaged, and lamp damage caused by misconnection of mains supply or lightning stroke surge is avoided. Through the arrangement of the filter circuit and the surge absorption circuit, filtering and surge absorption are realized, and the dimming interface is effectively prevented from being damaged.

The utility model relates to the technical field of high-voltage looped network switch cabinets, in particular to a rainproof and lightning-proof outdoor high-voltage looped network switch cabinet, which comprises a main body, a lightning protection component is fixedly connected inside the main body, and a movable fixing component is arranged at the bottom of the main body. According to the utility model, the surge protectors are installed on the power supply input end and the important data line of the high-voltage looped network switch cabinet, so that lightning surge and voltage peak can be effectively blocked, the shielding cable can reduce electromagnetic interference, and the signal lightning protection device is installed at the signal line inlet of the high-voltage looped network switch cabinet, so that the lightning protection effect is improved. The high-voltage looped network switch cabinet can be effectively protected, the distance between the bottom plate and the ground feet can be controlled by adjusting stretching and retracting of the supporting rods, then suspension or landing of the moving wheels can be controlled, and therefore the high-voltage looped network switch cabinet can be conveniently moved and fixed.

An inverter, comprising: a DC surge protection apparatus, a DC bus, an inverter circuit, a measurement apparatus, an AC surge protection apparatus, a measurement apparatus and a controller. A DC end of the inverter circuit is connected to a DC port of the inverter by means of the DC bus, and an AC end of the inverter circuit is connected to an AC port of the inverter. The measurement apparatuses are arranged in a surge loop of the inverter, and are configured to measure electrical parameters of the surge loop, the surge loop being a flow path of a surge current in the inverter. The controller is configured to control turn-off of switching devices in the inverter circuit when the electrical parameters measured by the measurement apparatuses satisfy a lightning surge condition, and turn on the DC surge protection apparatus and the AC surge protection apparatus after the switching devices are turned off.

The invention discloses a surge suppression circuit and an electronic device. The electronic device comprises a series loop formed by a rectification circuit and a capacitor. The surge suppression circuit comprises a current-limiting resistor, a thyristor, a driving enhancement module and a driving and power supply module, the current-limiting resistor and the thyristor are connected in parallel and then connected to a series loop, a first end of the driving enhancement module is connected with a control electrode of the thyristor, a second end is connected with an anode of the thyristor, and an output end of the driving and power supply module is connected with a third end of the driving enhancement module; the driving enhancement module comprises a first switch tube, and the driving and power supply module comprises a second switch tube; after the electronic device is started, when the voltage at the two ends of the capacitor achieves the effect of suppressing input impact current or inputting lightning surge, the second switch tube is conducted, and the driving and power supply module provides first driving current for the thyristor through the driving enhancement module and conducts the first switch tube. The conduction of the first switch tube enables the voltage output by the rectification circuit to provide a second driving current for the thyristor through the driving enhancement module. The reliability can be improved.

To provide a lightning protection device that reduces energy loss. [Solution] The device comprises a surge-resistant transformer 1 for suppressing the transition voltage of lightning surges, and a filter circuit 2 connected to the primary side of the surge-resistant transformer. The impedance of the filter circuit 2 is 100Ω or more and less than 1000Ω. The frequency-to-gain characteristics of the lightning protection device are such that the gain is maintained at 0 in the frequency band of 100Hz or less, and the gain is 0 or less near the frequency corresponding to the resonance point of the surge-resistant transformer 1.

The utility model discloses a lightning -resistant circuit, including rectifier bridge BD1, the input of rectifier bridge BD1 connects the live wire L and zero line N of commercial power, and the live wire L and zero line N between being connected with pressure -sensitive resistance MOV1, and the live wire L has the fuse F1 in series, and rectifier bridge BD1 and commercial power between having common mode inductance LF1 and common mode inductance LF2 in series, and common mode inductance LF1 and common mode inductance LF2 between being connected with capacitor CX1 and thermistor NTC4. When lightning voltage enters from the live wire L and zero line N, first, after absorbing through pressure -sensitive resistance MOV1, then, through the high impedance structure that is formed by common mode inductance LF1 and common mode inductance LF2 in series, make the lightning surge current of whole circuit greatly reduce, reduced the influence of lightning to the post stage circuit.

The utility model discloses a lightning surge protection device of adaptation to different installation space, including mounting seat, the one side of mounting seat is provided with a plurality of protector main parts, and the top of mounting seat is provided with a plurality of wiring slots corresponding with a plurality of protector main parts, and the fixed peg is seted up in wiring slot, the sliding fit of the movable rod corresponding with a plurality of protector main parts is had in mounting seat, and the elastic cooperation of two clamping rods is had in the one side of movable rod, and the protector main part is connected with two clamping rods, and the rotary fit of two -way screw rod is had in mounting seat, and the sliding fit of lifting cylinder is had in the top and bottom of mounting seat, and two -way screw rod is cooperated with two lifting cylinders threadedly, the utility model discloses the lifting cylinder of setting, can rotate two -way screw rod and drive two lifting cylinders to be far from each other, make two lifting cylinders support and fix to mounting seat, thereby being convenient for the space in the inside of switch board to support installation, uses different installation space and installation mode, and it is convenient to use in the narrow space.

The invention provides a thunder and lightning protection device for photoelectric navigation equipment, the photoelectric navigation equipment comprises an outboard device and an in-cabin device, the outboard device and the in-cabin device are connected through a connecting cable, and the thunder and lightning protection device comprises an outboard device thunder and lightning suppression module and an in-cabin device thunder and lightning protection module; the outboard equipment lightning suppression module is installed inside the outboard equipment, the in-cabin equipment lightning protection module is connected to the connecting cable in series, and the in-cabin equipment lightning protection module is grounded through an independent current loop. The outboard equipment lightning suppression module serves as a first defense line for lightning protection, is installed in outboard equipment (such as a photoelectric sensor, an antenna, an external detector and the like which are exposed in a complex electromagnetic environment), and preferentially suppresses lightning indirect effects (such as inductive lightning surge and electrostatic discharge) entering from outboard cable coupling. And surge energy is prevented from being directly transmitted into the connecting cable.

The utility model provides a kind of anti-collision mechanism for intelligent base, including base, base includes base layer and protective layer, the upper portion of base is provided with protective box, the upper portion of protective box is provided with sealing cover, the upper portion of sealing cover is provided with storage box, the inside of storage box is provided with lightning surge protection equipment electrically connected with ground wire, the inside of storage box is provided with multiple partitions, the both outer side walls of storage box are hingedly provided with sealing door, the utility model can be through the height of storage box to be promoted by base cooperation protective box, and by the base layer and the protective layer of collective, avoid the impact force of foreign matter directly impacting on protective box or storage box to cause damage to power supply system or weak current system inside it, greatly improve the security and service life of intelligent base use, ensure the safety performance of power supply system and weak current system operation inside intelligent base.

The invention provides an adapter of a vehicle-mounted laser radar and the vehicle-mounted laser radar, and relates to the technical field of laser radars, and the adapter of the vehicle-mounted laser radar comprises a power supply module which comprises a power supply sub-module and a network sub-module which are connected with each other; a power supply surge protection circuit and a network surge protection circuit; wherein the power supply surge protection circuit is connected with the power supply sub-module and is connected with the vehicle-mounted laser radar; the network surge protection circuit is connected with the network sub-module and is connected with the vehicle-mounted laser radar, and the power supply surge protection circuit and the network surge protection circuit are both connected with the earth zero potential point. In the embodiment, the power supply surge protection circuit and the network surge protection circuit are connected with the earth zero potential point, the power supply surge protection circuit can protect a power supply unit in the vehicle-mounted laser radar from being damaged by lightning surge, and the network surge protection circuit can protect a communication network from being damaged by lightning surge. Therefore, the vehicle-mounted laser radar is jointly protected from being damaged by lightning surge.

A system for preventing semiconductor elements of a power converter from breaking down due to an overvoltage by a lightning surge in a multilevel power conversion system is provided. The multilevel power conversion system includes a multilevel power converter, and a controller that includes an operation control unit that causes an operation mode of the multilevel power converter to transition to a standby mode in which power conversion is not performed between a DC input / output unit and an AC input / output unit based on a predetermined condition, and a gate signal generation unit that generates and outputs a gate signal that puts at least one of a third semiconductor switching element or a second semiconductor switching element into a conducting state or a switching state in the standby mode.