48 results about "Current limiting reactor" patented technology

The invention provides a zero-loss deep current limiting device and a current limiting device control method, and relates to the technical field of transformer fault current limiting, the device comprises a main switch branch, an energy absorption branch, an artificial zero-crossing branch and a current limiting reactor; the main switch branch comprises a vacuum type quick switch which is positioned between the bus and the main transformer high-voltage winding connecting end part; the artificial zero-crossing branch and the modulation inductor are connected in series and then are connected in parallel to the main switch branch; the artificial zero-crossing branch comprises a zero-crossing energy storage capacitor and a vacuum trigger switch, and the zero-crossing energy storage capacitor and the vacuum trigger switch are connected in series; the current limiting reactor is connected in parallel to the vacuum type quick switch; and a controller for controlling the vacuum trigger switch and the vacuum type quick switch to work is also arranged in the device. The energy absorption branch comprises a zinc oxide resistor which is connected in parallel with the artificial zero-crossing branch. The current limiting reactor is small in loss in the normal running state of the system and high in running reliability when the system breaks down.

This invention relates to a method and system for protecting DC lines in a multi-terminal flexible DC system, belonging to the field of relay protection technology. It solves the problem in existing technologies where multi-terminal flexible DC system DC line protection struggles to accurately identify DC line faults under low communication requirements. The method includes collecting the voltage and current of the current-limiting reactors at both ends of the DC line to be protected in the multi-terminal flexible DC system before and after a fault occurs, thereby obtaining the high-frequency component frequency of the DC line to be protected at ω. f The voltage and current surges at both ends of the current-limiting reactor are used to determine the frequency of the DC line to be protected at a high-frequency component of ω. f The sudden energy change of the current-limiting reactors at both ends; according to the DC line to be protected at a high frequency component frequency of ω f The sudden energy change of the current-limiting reactors at both ends and the fault protection criteria are used to determine whether a fault has occurred in the DC line to be protected; if so, the protection action of the DC line to be protected is initiated.

1. Name of the product in this design: Current-limiting reactor. 2. Purpose of this design: To limit excessively rapid fault current. 3. The key design feature of this product is its shape. 4. The image or photograph that best illustrates the design's key points: 3D view 1.

The invention belongs to the technical field of power system relay protection and power distribution network flexible interconnection, and discloses a flexible loop closing device body topological structure, which comprises a double-core symmetric phase-shifting transformer and a mode switching interface unit, and is characterized in that the double-core symmetric phase-shifting transformer comprises an exciting transformer bank and a series transformer bank; the mode switching interface unit is arranged on a low-voltage electric energy coupling loop between the secondary side output end of the exciting transformer bank and the secondary side input end of the series transformer bank, and the mode switching interface unit is arranged on a low-voltage electric energy coupling loop between the secondary side output end of the exciting transformer bank and the secondary side input end of the series transformer bank. And the current-limiting impedance of the secondary side is mapped to the primary side by the square times of the transformation ratio, so that on the premise of not increasing the volume and cost of the external current-limiting reactor, the self-protection and fault current suppression of the body are realized, and the organic unification of steady-state current regulation and transient current limiting is realized. The invention also discloses a virtual impedance identification-based adaptive protection method matched with the topological structure of the flexible loop closing device body.

The invention provides a transformer short-circuit fault current limiting device and a capacitor maintenance management method in the device. The transformer short-circuit fault current limiting device comprises a main branch, a current limiting branch, a modulation inductor, an artificial zero-crossing branch and an energy consumption detection branch. The main branch is provided with a vacuum quick switch which is connected in series between the bus and the primary side port of the transformer; the current-limiting branch is provided with a current-limiting reactor which is connected in parallel with the vacuum quick switch. The artificial zero-crossing branch is connected in series with the modulation inductor and then is connected in parallel with the current-limiting branch, and the artificial zero-crossing branch comprises an energy-storage capacitor bank module and a vacuum trigger switch which are connected in series. In the application, when the fault current on the main branch is detected, the vacuum quick switch is firstly controlled to be switched off, and then the vacuum trigger switch is controlled to be switched on, so that the vacuum quick switch can be switched on and off conveniently; furthermore, the vacuum trigger switch is controlled to be turned off, the current limiting reactor is connected between the power distribution system bus and the transformer, short-circuit fault current limiting is achieved, and damage to the transformer when the load is short-circuited is reduced.

The invention discloses a fault current limiter system based on a novel liquid metal current limiter. The system is composed of a novel liquid metal current limiter, a quick switch and a current-limiting reactor. The novel liquid metal current limiter has the effects of shortening the initial current limiting time and quickly and accurately capturing short-circuit fault symptoms in the system. In the system, on one hand, the influence caused by the slowing of the self-contraction speed of the liquid metal is reduced through quick opening; on the other hand, the voltage at the two ends of the system is increased, the current transfer speed from the novel liquid metal current limiter branch to the current limiting reactor branch is increased, and the electric arc and ablation of the novel liquid metal current limiter are further weakened. The current limiting depth can be improved by adding the current limiting reactor, and the defect that the liquid metal current limiter only depends on electric arc current limiting is overcome through a current transfer mode, so that the novel liquid metal current limiter can be applied to the high-voltage field.

The invention discloses a series current limiting reactor state monitoring system and method, and belongs to the technical field of power equipment state monitoring. The system comprises a data acquisition module, a historical database module, a data fusion processing module, a comprehensive diagnosis module and an early warning module. According to the method, real-time multi-source data is collected and preprocessed, real-time multi-source fusion, historical trend fusion and scene-fault feature fusion are executed, a health index judgment state is calculated, and early warning is output. According to the method, historical data and scene parameters are combined through a multi-dimensional data fusion algorithm, so that the problems of high misjudgment rate and off-line detection lag in traditional monitoring of a single parameter are solved, the accuracy and the real-time performance of reactor state monitoring are improved, and reliable support is provided for operation and maintenance decision making.

The application relates to the technical field of power distribution networks, and discloses a novel DC power distribution network hybrid current limiter and a polarity self-recovery control method, wherein the hybrid current limiter comprises: hybrid current limiters which are respectively arranged in series between current limiters and DC circuit breakers at two ends of a DC line, and each end hybrid current limiter comprises a current passing branch, a current limiting branch and a commutation branch; the current passing branch is used for providing a current passing path; the current limiting branch is used for limiting the increase of a fault current; and the commutation branch is used for performing current commutation of the current passing branch and the current limiting branch to block the passing of the fault current from the current passing branch; the application not only improves the fault current limiting capacity of the DC power distribution network, but also reduces the breaking stress of the DC circuit breaker and the investment cost of the DC power distribution network system, and realizes fast reclosing.

The application discloses a fault current limiter input method based on a voltage drop criterion and belongs to the technical field of power system fault protection, which comprises the following steps: collecting three-phase voltage instantaneous values of a fault current limiter installation point and calculating zero sequence voltage; synchronously calculating real-time voltage amplitude and voltage change rate; comparing the real-time voltage amplitude and the voltage change rate with preset criteria and combining zero sequence voltage auxiliary criteria to determine a ground fault; quickly opening a switch to input a current limiting reactor when the fault occurs; and closing the switch to exit the current limiting reactor after the fault is eliminated. The application adopts a comprehensive design of double main criteria of voltage amplitude and voltage change rate plus zero sequence voltage auxiliary criteria, can accurately distinguish a ground fault from normal fluctuations of a power grid, avoids misjudgment and missed judgment, has a quick sampling response, realizes quick input of current limiting by cooperating with a quick switch, can be self-adaptively adjusted according to actual power grid parameters and operating conditions, can effectively suppress a fault current peak value, prevents power equipment from being damaged, and practically improves the safe and stable operation level of a power system.

The invention relates to a direct current transmission line single-ended traveling wave protection method based on a fault voltage first traveling wave area ratio. The method comprises the following steps: S1, determining an internal and external fault identification criterion of a forward region; s2, establishing a protection starting criterion; s3, establishing a fault direction criterion; s4, establishing a fault pole selection criterion; and S5, determining a protection scheme. According to the method, internal and external faults can be identified and accurately distinguished within 1ms, high sensitivity and reliability are still achieved under the high-resistance fault condition, and meanwhile good robustness is achieved under noise interference and parameter change of the current limiting reactor.

The invention relates to a test circuit and a test method for a distributed static synchronous series compensator, and the test circuit enables the steady-state current of a test power supply, a rectification circuit, a controllable voltage source, a transformer and a current-limiting reactor simulation line to be continuous, accurate and adjustable through switching on or switching off a circuit breaker, a high-speed switch and a high-speed bypass switch, and the test power supply is low in capacity. The method has the advantages that different states of the distributed static synchronous series compensator can be tested, the sub-modules of the distributed static synchronous series compensator can be tested in batches at the same time, the test efficiency is high, the technical economy is prominent, a high-capacity test power supply is not needed, and the test cost is low. All sub-modules of the distributed static synchronous series compensator can be tested at the same time under the laboratory condition.

The utility model provides a wind generating set high voltage ride through test device comprising a test box body, two ends of the test box body are respectively connected with a connecting lead, and the tail end of the connecting lead is provided with a fixing assembly; a test circuit board and a super capacitor module are arranged in the test box body, a display screen is arranged at the top of the test box body, a protective shell is arranged on the outer side of the display screen, and the test circuit board can be connected between a tested wind turbine generator and a power grid through connecting wires at the two ends. The test circuit board is provided with a current limiting reactor group, a parallel capacitor group, a thyristor and a plurality of groups of circuit breakers, and the super capacitor module is connected with a direct current bus of the tested wind turbine generator. The test equipment can solve the problems of poor connection stability, inaccurate voltage simulation and low test automation degree in the prior art.

The utility model belongs to the technical field of power equipment, and discloses a vehicle-mounted reactive power compensation device. According to the vehicle-mounted reactive power compensation device, the design that the first-layer frame and the second-layer frame are stacked in the first direction is adopted, the first-layer three-phase capacitor module and the second-layer three-phase capacitor module are installed on the first-layer frame and the second-layer frame respectively, the space utilization rate of a trailer plate is greatly increased, and compared with traditional single-layer arrangement, the three-dimensional layout has the advantages that the space utilization rate is greatly increased; more devices can be accommodated in the same trailer area, and the reactive compensation requirement of larger capacity is met; the first-layer frame and the second-layer frame are detachably connected, so that the equipment is more convenient to mount, dismount and maintain, and the expansibility is improved; and at least part of busbars in the three-phase inlet wire busbar group are arranged in an L shape, so that the wiring complexity is reduced, the electrical connection between the capacitor bank and the current limiting reactor is facilitated, the wiring flexibility of the three-phase inlet wire busbar group can be improved, and the space utilization rate is further improved.

This invention discloses a short-circuit current limiting system and method, relating to the field of short-circuit current limiting, including a fast switch and a current-limiting reactor; the fast switch includes an arc-extinguishing chamber and a fast mechanism, the fast mechanism including an electromagnetic drive component and a trigger circuit; the method comprises: calculating and obtaining the peak value of the first half-wave short-circuit current and the time of the first zero-crossing point; determining whether the fast switch should trip based on the peak value of the first half-wave, thereby reducing the number of system trips; determining the tripping time of the fast switch based on the zero-crossing point, thereby reducing the arc-extinguishing chamber arcing time; calculating and obtaining the peak value of TRV, adjusting the charging voltage of the trigger circuit based on the peak value of TRV, reducing the stress on the fast mechanism, thereby improving the overall lifespan of the system.

The application discloses a zero-loss deep current-limiting protection device, and relates to the technical field of protection devices.The device comprises a base, a control cabinet is arranged on one side of the top end of the base, a plurality of protection devices are arranged on one side of the control cabinet, and a refrigeration mechanism is arranged in the control cabinet.The refrigeration mechanism comprises a gas feeding pipe, a refrigeration device, an arc-shaped pipe, a flow guide pipe, a guide plate and a partition plate, the refrigeration device is arranged at the bottom end in the control cabinet, and the gas feeding pipe is arranged at the bottom end of the refrigeration device.The protection device comprises a fixing seat, a quick circuit breaker, a cylinder-type converter and a current-limiting reactor, the bottom end of the fixing seat is in contact with the top end of the base, and the quick circuit breaker is fixedly connected to the top end of the fixing seat.The zero-loss deep current-limiting protection device can guarantee the cooling effect, reduce the influence of liquid water on internal elements, and can complete the closing and opening operations in a short time because the vortex disc force direction is coaxial with the moving contact movement direction.

The application provides a circuit breaker with a current limiting reactor LR switching function, comprising a mechanical switch K1, a first thyristor D1, a current limiting reactor LR, a coupling inductor LO and a power supply VDD; the positive pole of the mechanical switch K1 is connected with the current limiting reactor LR, the first thyristor D1 and the power supply VDD respectively; the negative pole of the mechanical switch K1 is connected with the current limiting reactor LR, the first thyristor D1 and a vacuum switch K2 through the primary side of the coupling inductor LO respectively; the negative pole of the vacuum switch K2 is connected with the negative pole of the power supply VDD through a load R. In the rated operation of the circuit breaker, the current only passes through the mechanical switch and the vacuum switch, so that the system loss is reduced and the energy transmission efficiency of the circuit breaker is improved; in the fault state, the current limiting reactor is put into operation, which can limit the rising rate of the system fault current, thereby providing favorable guarantee for the circuit breaker to remove the fault; and the rate of the fault transient current transferred from the mechanical switch to the current limiting reactor is improved.

The utility model discloses a star-shaped frame for a bridge arm reactor and a current-limiting reactor, and the star-shaped frame comprises a central shaft which comprises axial grooves which are uniformly distributed in the axial direction; the axial groove comprises a lifting insertion groove, a confluence insertion groove and a star-shaped arm insertion groove; the at least three lifting arms are inserted and welded with the central shaft through the lifting slots; the confluence arm is inserted and welded with the central shaft through the confluence slot; a terminal plate is fixed on the confluence arm along a central shaft; the confluence arm comprises a first aluminum bar, a confluence arm reinforcing steel plate, an insulating plate and a second aluminum bar which are stacked in sequence; the star-shaped arm is inserted and welded with the central shaft through the star-shaped arm slot; and the star-shaped frame reinforcing plate is used for sequentially fixing the hoisting arm, the converging arm and the star-shaped arm in the circumferential direction by taking the central shaft as the axis. The confluence arm is manufactured into two layers of aluminum bars, and the confluence arm reinforcing steel plate and the insulating plate are arranged between the two layers of aluminum bars, so that the effect of shunting current is achieved, the phenomenon of abnormal temperature rise is avoided under the condition that the conductive cross section is reduced, stable hoisting can be performed, and stable use of the star-shaped frame is ensured.

The invention provides a zero-loss current limiting device based on an artificial zero-crossing technology and a device monitoring and maintenance method, and relates to a transformer fault current limiting technology, the device comprises a main switch branch, an energy absorption branch and an artificial zero-crossing branch; the main switch branch comprises a vacuum fast switch, the vacuum fast switch is connected in series between a bus of the power distribution system and the input end of the main transformer, and the vacuum fast switch is connected in parallel with a current limiting reactor; a modulation inductor is connected in series between the main switch branch and the artificial zero-crossing branch, and the energy absorption branch is connected in parallel to the artificial zero-crossing branch; the energy absorption branch comprises a plurality of zinc oxide resistors, and a nonlinear resistor module is formed by the plurality of zinc oxide resistors; the artificial zero-crossing branch comprises an energy storage unit and a trigger switch, the energy storage unit at least comprises a zero-crossing energy storage capacitor, and the zero-crossing energy storage capacitor and the trigger switch are connected in series. The zero-crossing energy storage capacitor releases electric energy to artificially produce a zero-crossing point, so that rapid opening of the vacuum rapid switch is facilitated, and short-circuit fault current limiting is realized.

The invention discloses a fault current limiter and a control method thereof, and belongs to the technical field of fault current limiting, the fault current limiter comprises a plurality of current limiting modules, a first measurement CT, a control and protection device and an energy supply system, each current limiting module comprises a high-speed switch and a current limiting reactor, and the second measurement CT, the high-speed switch and the current limiting reactor are connected in parallel. The second measurement CT collects the current flowing through the current limiting reactor; the quick switch comprises a switch body and a trigger loop, and the trigger loop outputs energy to open and close the switch body. The first measurement CT measures the current flowing through the current limiting module; the control and protection device collects current values of the first measurement CT and the second measurement CT, collects signals of the quick switch and controls the quick switch to be turned on and off. The first measurement CT and the second measurement CT are directly connected with the control and protection device to supply a current value, or the current value is transferred and supplied through a trigger loop; the energy supply system provides operation energy for the trigger loop. The purpose of the invention is to solve the problem that the CT cannot obtain energy when the bus current is small.

The application discloses a zero-loss deep-limit current and bus residual voltage integrated reactor and relates to the technical field of reactors.The application comprises a device box, a control box and a plurality of reactor units; a row of reactor units is installed in the device box; the plurality of reactor units are connected in parallel to form a reactor module; an overspeed two-cut switch is arranged on a fire line of each power supply branch line; a synchronous overspeed switch is arranged on an electric reactance output branch line in correspondence; the device box is provided with the control box on the outside; a control panel is arranged in the control box; and the overspeed switches are sequentially closed for a short time in milliseconds.The application can effectively control current limiting and maintain bus voltage by designing a row of reactor units, and can solve the problems that the current limiting depth is insufficient or the normal voltage drop is too large when the existing current limiting reactor L and residual voltage maintaining reactor Lb are combined, and the two indexes cannot be met simultaneously.

The application relates to a built-in current-limiting reactor, which comprises an upper yoke, a coil and a lower yoke arranged in sequence from top to bottom, wherein the upper yoke is provided with an upper yoke frame, the upper side of the upper yoke frame is provided with an upper connecting seat, the inside of the upper yoke frame is provided with upper silicon steel sheets, the upper silicon steel sheets are insulated from the upper yoke frame and connected with the upper connecting seat, the upper connecting seat is connected with a corresponding upper clamp of a transformer, the lower yoke is provided with a lower yoke frame, the lower side of the lower yoke frame is provided with a foot pad, the inside of the lower yoke frame is provided with lower silicon steel sheets, the lower silicon steel sheets are insulated from the lower yoke frame and connected with the corresponding foot pad, the foot pad is connected with a corresponding lower clamp of the transformer, vertical screw rods are arranged between the upper yoke and the lower yoke, the upper ends of the vertical screw rods are fixedly connected with the corresponding upper connecting seats, the lower ends of the vertical screw rods are fixedly connected with the corresponding foot pads, upper lead wire rows and lower lead wire rows are arranged outside the coil, and the upper lead wire rows and the lower lead wire rows are respectively connected with corresponding low-voltage lead wire rows of the transformer. The built-in current-limiting reactor has lower cost, smaller loss, stronger short-circuit resistance, shortened production cycle and reduced installation space.

1. Name of the designed product: current limiting reactor. 2. Use of the designed product: for suppressing current. 3. Design points of the designed product: in shape. 4. Picture or photo best indicating the design points: perspective view 1.

The application discloses a circuit breaker topology suitable for inhibiting DC faults and a control method thereof U The discharge branch, the voltage limiting branch composed of a first thyristor SCR1 and a second thyristor SCR2, and a current limiting branch; the current limiting branch comprises a current limiting reactor L lim and a resistor R lim ; the transfer branch is composed of a first semiconductor switch IGBT T unit in series and parallel connection, the energy absorption branch comprises a metal oxide varistor MOV, and the main branch circuit comprises an ultra-fast isolation switch UFD; the main branch circuit, the transfer branch, the energy absorption branch and the voltage limiting branch are connected in parallel, and are connected in series with the current limiting branch. The current limiting branch designed in the application can be started rapidly in the initial stage of the fault, and effectively reduces the overcurrent amplitude in the initial stage. Meanwhile, through the synergistic effect of the voltage limiting branch, the overvoltage problem in the fault isolation process is significantly reduced, the breaking capacity, safety, reliability, economy of the circuit breaker are improved, and a powerful guarantee is provided for the stable operation of the power grid.

The invention discloses a nuclear power ship electrical system and method based on hierarchical collaborative current limiting, and the system comprises a primary dry-type current-limiting reactance unit which is connected in series with a main power distribution output side main loop of a nuclear power ship and is provided with an impedance adjustable mechanism; the partition-level dry-type current-limiting reactance units are connected in series with the power distribution input ends of the load partitions in a one-to-one correspondence manner, and the partition-level dry-type current-limiting reactance units and the main-level dry-type current-limiting reactance units form a graded current-limiting framework; a state detection unit of the intelligent cooperative control module is electrically connected with a main loop and each load partition loop to collect electrical parameters, a central control unit is in signal connection with an execution unit, and the execution unit is linked with an impedance adjustable mechanism of a main-level dry-type current-limiting reactance unit and an impedance adjustable mechanism of a partition-level dry-type current-limiting reactance unit. And an integrated optimization scheme of grading precise current limiting, intelligent cooperative control, safety redundancy guarantee and compact integrated design can be realized, so that the technical problems are solved, and the comprehensive performance of the electrical system of the nuclear power ship is improved.

The invention provides a platform integrated current limiter which comprises a high-potential platform, a current limiting reactor, a fast switch, a control unit, an isolation transformer and an optical fiber insulator, the current limiting reactor, the fast switch, the control unit, the isolation transformer and the optical fiber insulator are arranged on the high-potential platform, and the current limiting reactor and the fast switch are connected in parallel. The current-limiting reactor is used for limiting short-circuit current when a line fault occurs, the quick switch is used for closing or opening the line so that the current-limiting reactor can exit from or be put into the line, the control unit is used for collecting equipment parameters and receiving ground control signals, and the isolation transformer is used for transmitting a ground potential power supply to the high-potential platform. The optical fiber insulator is used for communication between the high-potential platform and the ground. According to the application, the equipment is all integrated to a high-potential platform, the integration level is high, the expandability is good, the projection area occupied by the equipment is reduced, the reliability is improved, the current limiting reactor and the quick switch are connected in parallel, a long insulating pull rod is not needed, and the structure is simple.

The application discloses a current-limiting controllable phase shifter and a control method thereof, which is installed at a power distribution network loop closing point to realize AC loop closing of the power distribution network, and comprises a controllable phase shifter, a current-limiting reactor and a fast tie switch K2 connected in series, and fast bypass switches K1 connected in parallel at both ends of the current-limiting reactor; each component is controlled to adapt to different operation states of the power distribution network. The application can realize AC loop closing of the power distribution network, solves the contradiction between poor reliability of open-loop operation and electromagnetic loop network existing in closed-loop operation of the power distribution network, and has low equipment cost and saves land occupation; meanwhile, the application realizes power flow control after being connected, and can greatly promote local consumption of new energy.

The embodiment of the invention provides a 500kV oil-immersed current-limiting reactor mechanical instability online monitoring and diagnosing system and method, and the method comprises the steps: a high-precision synchronous collection unit synchronously collects multi-point vibration signals and current signals through high-precision time, and a signal processing unit carries out the signal processing and feature extraction of the multi-point vibration signals, and obtains vibration mode features; the current signal processing and feature extraction are carried out on the current signal to obtain a current feature, the correlation analysis unit establishes and continuously analyzes a dynamic correlation relationship between the vibration mode feature and the current feature in a time sequence, and the diagnosis and early warning unit analyzes a result based on the vibration mode feature, the current feature and the dynamic correlation relationship. And performing state evaluation, early warning and fault diagnosis on the mechanical stability of the reactor by adopting a preset diagnosis model. According to the method, the limitation of traditional single sensor monitoring is broken through, the diagnosis accuracy is improved, the false alarm rate and the missing report rate are reduced, the operation and maintenance management level of equipment is improved, and safe and stable operation of a power grid is guaranteed.

The invention discloses a power system short-circuit current limiting device and method based on isolation knife switch combined operation. The device comprises a current limiting reactor, a first isolation knife switch, a second isolation knife switch, a third isolation knife switch, a fourth isolation knife switch, a grounding knife switch, a bypass knife switch, a capacitor bank and a control unit. The method comprises the following steps: collecting the current and voltage of a line in real time by using a current transformer and a voltage transformer; when the line current is greater than or equal to a first preset current threshold and the current change rate is greater than a preset change rate threshold, determining a line fault; according to the line current and voltage, identifying a short-circuit fault type by using a wavelet transform algorithm; and controlling on and off of the first isolation disconnecting link, the second isolation disconnecting link, the third isolation disconnecting link and the fourth isolation disconnecting link so as to limit the short-circuit current. The invention has the characteristics of obvious short-circuit current limiting effect, extremely low normal operation loss, high response speed, obvious cost advantage, strong compatibility and convenience in maintenance.

The invention relates to the field of static synchronous phase modifiers, and discloses a control method and device for a super-capacitor valve in a static synchronous phase modifier system, and the device comprises an MMC converter valve AC side equipped with a circuit breaker, a pre-charging resistor and a bypass switch, and the super-capacitor valve equipped with a current limiting reactor, a current limiting resistor, a bypass switch and an anode and cathode circuit breaker. A current-limiting resistor and a bypass switch are additionally arranged at a direct current bus between a modular multilevel converter and a super-capacitor valve, so that the impact current at the closing moment of a direct current circuit breaker can be obviously reduced, and in combination with a controllable charging strategy of the super-capacitor valve, the capacitor voltage of each sub-module can be charged to a rated value and is kept consistent; according to controllable charging and frequency-active power control of the super-capacitor valve of the static synchronous phase modifier, active power output of the super-capacitor valve can be automatically adjusted according to the frequency of the grid-side voltage after the system is started, frequency stabilization of a power grid is facilitated, primary frequency modulation and inertia supporting are achieved, and stable starting of the static synchronous phase modifier and the power grid supporting capacity are achieved.