199 results about "Electromagnetic power" patented technology

The invention belongs to the technical field of electromagnetic induction and friction nanometer power generation, and particularly relates to a vibration energy collector based on electromagnetic induction and friction nanometer hybrid power generation. Comprising a friction nanometer power generation unit and an electromagnetic induction unit. The friction nanometer power generation unit comprises an upper insulating support plate, a lower insulating support plate and a friction pair; the friction pair comprises an upper friction assembly and a lower friction assembly, and the upper friction assembly and the lower friction assembly trigger the contact and separation process through external vibration to achieve friction electricity generation. The electromagnetic induction unit comprises a coil, a magnet and a steel body which are sequentially nested, the coil and the magnet are fixedly connected with the upper friction assembly and the lower friction assembly respectively, the steel body is fixedly connected with the lower insulation supporting plate, the magnet and the steel body form a closed magnetic circuit, and the magnet and the coil trigger relative movement through external vibration to achieve electromagnetic power generation. The device is novel in structure and distinct in gradation, integrates a triboelectrification effect and an electromagnetic induction principle, has high-voltage output and high-current characteristics, and can efficiently realize continuous conversion from environment vibration energy to electric energy.

The invention discloses a grid-connected pre-synchronization method of a virtual synchronous generator parallel system and electronic equipment. The grid-connected pre-synchronization method of the virtual synchronous generator parallel system comprises the following steps: n virtual synchronous generators start to execute grid-connected pre-synchronization after receiving a pre-synchronization instruction, wherein the grid-connected pre-synchronization comprises frequency and phase pre-synchronization and amplitude pre-synchronization; the frequency and phase pre-synchronization comprises the steps of calculating frequency and phase pre-synchronization control quantity, calculating damping power according to the frequency and phase pre-synchronization control quantity, and calculating an output angular frequency difference of the virtual synchronous generator according to mechanical power, electromagnetic power and damping power; and determining the power angle of the virtual synchronous generator according to the output angular frequency difference of the virtual synchronous generator and the rated angular frequency. According to the invention, communication-free pre-synchronization can be realized, communication can also be realized through a communication method, the control is flexible and simple, and the requirement on communication reliability is not high.

The invention discloses a direct-driven fan system impedance modeling method considering frequency coupling, and the method comprises the steps: S1, obtaining a mathematical expression of a blade tip speed ratio and output power according to a wind turbine airflow model of a direct-driven fan; s2, according to equivalent circuit topology modeling under a dq coordinate system of the permanent magnet synchronous motor, obtaining an expression of electromagnetic torque and electromagnetic power; s3, according to the control structures of the machine-side converter and the grid-side converter of the direct-drive fan, modeling is carried out respectively, and an equivalent admittance mathematical expression of the machine-side converter and six disturbance admittance expressions in the direct-drive fan are obtained; and S4, based on the mathematical expressions of the output power, the electromagnetic power, the equivalent admittance and the disturbance admittance obtained in S1, S2 and S3, establishing the equivalent admittance / impedance of the direct-drive fan system. According to the method, multi-time-scale control and full-working-condition frequency domain port characteristics of the direct-driven fan system can be effectively represented, and the equivalent impedance model can accurately analyze the stability of the system.

The invention relates to a friction and electromagnetic combined type wave energy power generation device, and relates to the field of wave energy power generation devices. Comprising a cylindrical shell, a floating ball structure and a stress disc. The first end of the cylindrical shell is sealed, a fixed shaft is fixed to the inner axis and slidably sleeved with a sliding framework, and a composite power generation assembly is arranged in the cylindrical shell. When waves exist on the sea surface, due to the fact that the floating ball structure is subjected to buoyancy and thrust of the waves, the stress disc and the floating ball structure are subjected to opposite force, and the sliding framework can move relative to the fixed shaft, so that electromagnetic power generation and friction power generation are achieved. Even if the sea surface is flat and quiet, as long as the water body below the sea surface flows relatively and the flow velocity difference exists between the upper part and the lower part of the stress disc, buoyancy or sinking force can be generated, the sliding framework can move relative to the fixed shaft, and finally electromagnetic power generation and friction power generation are realized, so that the power generation efficiency is effectively improved.

The invention relates to an optimal power capturing method for a wave energy power generation device of a mixed-flow type air turbine, and belongs to the field of wave energy power generation. The optimal power capturing method comprises the steps that the change condition of the average output power of the turbine under different sea conditions along with the rotating speed is tested, and the maximum average output power point of the turbine under each sea condition is obtained; fitting the maximum average output power point under each sea condition to obtain a control law of the electromagnetic power of the motor; the quadrature-axis current reference value of the stator is made to be equal to zero, and the direct-axis current reference value of the stator is calculated; calculating a stator quadrature-direct axis current error term, and establishing a positive definite Lyapunov function; deriving the Lyapunov function, substituting the Lyapunov function into a stator quadrature-direct axis current state equation, and then performing transformation according to a first stability theorem to obtain a stator quadrature-direct axis voltage control law; and generating a corresponding SVPWM (Space Vector Pulse Width Modulation) switching signal according to a stator quadrature-axis voltage control law so as to control a motor-side converter and realize control on a turbine. The wave energy capturing efficiency can be improved.

The invention discloses a wave self-adjusting bistable electromagnetic-friction power generation device, and belongs to the field of ocean engineering renewable energy sources, the wave self-adjusting bistable electromagnetic-friction power generation device comprises a shell main body, an energy capturing mechanism and an energy conversion mechanism, the shell main body comprises a cylindrical shell, a top plate, a partition plate and a bottom plate, and the partition plate divides the shell main body into an upper section and a lower section; the energy capturing mechanism is arranged in the lower section, the energy conversion mechanism is arranged in the upper section, and the energy capturing mechanism and the energy conversion mechanism are rotationally connected. The self-adjusting bistable mechanism is introduced, through cooperation of the piston assembly and the plate spring, the position height of the potential barrier can be automatically adjusted, inter-well oscillation can be achieved when the wave exciting force is small, the motion amplitude of the mass block is enlarged, and therefore the energy capturing efficiency is improved; the energy conversion mechanism is designed to combine electromagnetic power generation with nanometer friction power generation, the energy conversion efficiency, reliability and stability of the device are improved, and the device is compact in structure, convenient to install and suitable for being directly used in a ship body.

The invention relates to the technical field of power transmission line self-energy-taking, and discloses a power transmission line self-energy-taking device and a state detection system, and the device comprises a housing structure, a motion structure, an electromagnetic power generation structure, and a friction power generation structure. Wherein the moving structure is composed of a permanent magnet, a spring and a fixing groove, the vertical shell and the fixing groove are connected through the spring, and a spring mass vibration system is constructed; the electromagnetic power generation structure generates power through relative movement of a permanent magnet and a coil. The friction power generation structure generates power through sliding separation of sliding electrodes on the side faces of the fixing grooves and electrodes in the side shells. The invention further discloses a state detection system, vibration energy is collected through the device and stored in an energy storage battery through an energy management circuit to supply power to a sensor detection circuit, and data are sent to an upper computer through a wireless transmission module. The power transmission line state real-time detection without external energy supply can be realized, and the problem of power supply of monitoring equipment in remote areas is solved.

The invention relates to a multi-degree-of-freedom composite wave energy converter, and belongs to the technical field of wave power generation. Comprising a mounting frame and a power generation assembly, and the power generation assembly comprises an electromagnetic power generation unit, a nanometer friction power generation unit and a piezoelectric power generation unit; the electromagnetic power generation unit comprises a gravity pendulum and an electromagnetic generator; the gravity pendulum is rotationally mounted on the mounting frame around the gravity center axis of the wave energy converter, and one end of the gravity pendulum is connected with a rotor of the electromagnetic generator; the nanometer friction power generation unit comprises a plurality of power generation parts made of friction materials, the power generation parts are installed on the installation frame, and under the action of external force, the power generation parts move relatively to generate electric energy; the piezoelectric power generation unit comprises a piezoelectric generator and a water flow turbine; a rotor shaft of the piezoelectric generator is connected with the water flow turbine, a rotor of the piezoelectric generator is made of piezoelectric materials, and magnets are arranged on the rotor and a stator respectively. The multi-degree-of-freedom wave capturing device can comprehensively and efficiently capture waves in multiple degrees of freedom, and is high in energy conversion efficiency and wide in application range.

The invention discloses a control method, device, equipment, medium and product of a network-forming type permanent magnet wind power system, and the method comprises the steps: calculating the maximum wind energy tracking power outputted by the network-forming type permanent magnet wind power system under the optimal wind energy tracking based on the maximum wind energy tracking coefficient; calculating a direct-current voltage damping control coefficient of a side damping controller according to the inertia coefficient and the damping coefficient of the direct-current voltage; calculating an electromagnetic power reference value output by the permanent magnet synchronous generator according to the maximum wind energy tracking power and the DC voltage damping control coefficient; and subtracting the electromagnetic power reference value from the electromagnetic power actual value, and inputting the difference value into a machine side active power controller so as to adjust the electromagnetic power output by the permanent magnet synchronous generator. According to the method, on the basis of not adding hardware equipment, the transient stability of the grid-forming type permanent magnet wind power system during the short-circuit fault period of the power grid can be remarkably improved only by changing the control strategy of the machine-side converter of the grid-forming type permanent magnet wind power system.

The invention provides a permanent magnet synchronous motor control method, an air conditioner and a storage medium. The method comprises the steps that a permanent magnet synchronous motor is controlled to operate according to a preset motor current-frequency ratio; when the given current and the given rotation frequency meet the condition of switching rotation speed closed-loop estimation operation, the given current is controlled to be gradually reduced at a preset amplitude, and a direct-axis estimation counter electromotive force amplitude and a quadrature-axis estimation counter electromotive force amplitude under the estimation rotation coordinate system after the given current is reduced each time are obtained; and when the direct-axis estimated counter electromotive force amplitude is equal to the quadrature-axis estimated counter electromotive force amplitude, switching to rotating speed closed-loop estimation operation. Meanwhile, the given rotation frequency is corrected by adopting an electromagnetic power high-frequency component. By applying the permanent magnet synchronous motor control method, speed smoothing of switching from motor current-frequency ratio control to rotating speed closed-loop estimation control can be realized in both the light-load state and the heavy-load state of the motor. And by adopting the frequency correction method disclosed by the invention, the electromagnetic torque oscillation is smaller, and the stability margin is more sufficient.

The invention provides a generator tripping sensitivity calculation method and system for transient stability control. The method comprises the steps that power angle trajectory data of an instability scene of a power system are combined with a composite power angle algorithm to carry out unit grouping; calculating a comprehensive difference value of the accumulated unbalanced energy and the decelerable area of the equivalent unit before and after generator tripping to form an estimated value of the unbalanced energy directly taken away by the generator tripping; calculating the electromagnetic power transfer amount of a cut unit by utilizing power flow information at the cutting moment and the network topology of the power system, and calculating the variable amount of a slowable area by combining with an equivalent unit power angle curve translation change hypothesis; finally, unbalance energy directly taken away by generator tripping and slowable area variation corresponding to power transfer are added to estimate stability margin variation, and the stability margin variation is divided by the capacity of the generator tripping unit to calculate generator tripping sensitivity. Based on the method, the invention further provides a generator tripping sensitivity calculation system for transient stability control. According to the method, an application prospect is provided for optimization decision-making of an online or real-time transient stability control generator tripping scheme.

The present invention belongs to the technical field of network-forming converters, and particularly relates to a method, system, device, and medium for determining the overcurrent capacity of network-forming converters. Aiming at the deficiencies of the existing method for calculating the current limit value corresponding to the critical clearing time of network-forming converters, which has a large amount of calculation, long time consumption, or cannot obtain the calculation result, the present invention adopts the following technical solutions: A method for determining the overcurrent capacity of network-forming converters considering transient synchronous stability, including: establishing a reduced-order simplified model of the network-forming converter under short-circuit faults; obtaining the electromagnetic power curves under steady state, during transient faults, and after fault clearing; obtaining the mechanical power curve considering damping power consumption; calculating the fault critical clearing angle and critical clearing time under the initial current limit and determining whether the requirements are met; increasing the current limit value until the calculated fault critical clearing time is greater than the actual fault clearing time. The beneficial effect of the present invention is: quickly and accurately obtaining the required minimum current limit value.

The present invention belongs to the technical field of water quality monitoring, and discloses a buoy-type self-powered water quality monitoring device, including an above-water mechanism and an underwater mechanism, wherein the above-water mechanism includes a floating component floating on the water surface, and a solar power generation component is arranged on the top of the floating component; the underwater mechanism includes a fixed shell, and a nano-friction power generation component and an electromagnetic power generation component are arranged on the fixed shell, and the nano-friction power generation component and the electromagnetic power generation component are coupled and arranged, and the nano-friction power generation component and the electromagnetic power generation component are respectively electrically connected to a control module; the bottom end of the floating component is lifted and lowered and provided with a monitoring component, and the monitoring component is electrically connected to the control module. The present invention has a compact structure and strong stability, improves the stability of the device on the water surface, and adopts a form of coupling parallel power generation in multiple power generation modes, and utilizes composite power generation technology to achieve stable power supply when the device floats on the water surface, and reduces the difficulty of equipment maintenance.

The present invention relates to the field of rail transit technology, and in particular to an electric door lock, including an electromagnetic power element with a linear power output end, and also includes an external latch lock; the external latch lock includes a latch, an elastic sheet, a partial sphere and a ball seat structure; the latch is coaxially connected to the partial sphere, and the ball seat structure partially fits and covers the partial sphere through a first limiting space; the elastic sheet is annularly sleeved on the periphery of the partial sphere, and is arranged between the ball seat structure and the latch, and fits with the first plane on the ball seat structure and the second plane on the latch respectively; when the first plane and the second plane are not parallel, the elastic sheet undergoes local deformation to obtain a reset force that causes the first plane and the second plane to return to a parallel position, and a locking groove is provided at the end of the latch. The present invention can effectively ensure the stability of the use of the electromagnetic power element and ensure its service life. At the same time, the present invention also requests protection for a swing electric door and rail transit equipment.

The utility model discloses an electromagnetic power generation device based on road vibration energy, which belongs to the technical field of energy recovery and reutilization, and comprises an energy input module which comprises a partition plate and a ball screw, a nut of the ball screw is fixedly connected with the partition plate, an elastic element is propped against the lower part of the partition plate along the axial direction of the ball screw, and an upper cover plate is buckled at the top of the partition plate; an energy conversion module; comprising a lower cylinder, a rotor is arranged in the center of the lower cylinder, a plurality of magnets are fixedly connected to the outer side of the rotor in the circumferential direction, and a plurality of coils are fixedly connected in the lower cylinder around the rotor; the motion transmission module comprises a middle barrel, and one end, away from the partition plate, of the elastic element is fixedly connected with the top surface of the middle barrel; a conversion transmission assembly is arranged in the middle barrel, converts irregular rotation of the ball screw into unidirectional rotation and transmits the unidirectional rotation to the rotor. Irregular vibration is converted into stable one-way rotation, the energy conversion efficiency is improved, and the reliability and durability of the device are enhanced.

A device is disclosed, which includes: a charge portion with a plurality of piezoelectric elements embedded in a tire configured for a vehicle, a capacitor mechanically coupled to the tire and electrically coupled to the plurality of piezoelectric elements; a transmitter coil, mechanically coupled to the tire and electrically coupled to the capacitor through a discharge portion; wherein in response to an external radial pressure on the tire resulting from movement of the vehicle which causes a pressure on the plurality of piezoelectric elements, the plurality of piezoelectric elements produce an electrical charge on the capacitor, and wherein the discharge portion electrically connects the electrical charge on the capacitor to the transmitter coil to send electromagnetic power to the vehicle.

The invention discloses a power equipment energy recovery method based on multi-modal processing, and relates to the technical field of electric energy data, and the method comprises the steps: S1, collecting load data, an electromagnetic power value and a recovered heat energy value generated by target power equipment; s2, abnormal periods with electromagnetic anomalies are screened out; s3, constructing a multi-modal learning network, and compensating and correcting the recovered heat energy value in the abnormal period; s4, a first reference heat energy value is set, and a corrected heat energy value is marked; and S5, judging whether the recovered heat energy value in the current abnormal period is corrected or not, and if not, executing the step S3 again. Compared with the prior art, the method has the advantages that the multi-modal learning network based on the electromagnetic power value and the load data is constructed, the energy recovery effect of the equipment in different load states can be accurately captured and automatically corrected again, and the method has the advantage of more accurately evaluating the recovered heat energy and the beneficial effect of improving the energy recovery efficiency of the power equipment.

According to an embodiment, a microwave circuit for detecting electromagnetic power coupled to a second port of the microwave circuit via a first port of the microwave circuit comprises at least one Josephson junction having a non-linear mode of operation; wherein a first current and a second current is configured to flow through the at least one Josephson junction; the microwave circuit is configured to couple electromagnetic power from the first port to the first current and to couple electromagnetic power from the second port to the second current; and the at least one Josephson junction is configured to cause a coupling between the electromagnetic power coupled to the second current and a phase shift of the first current, wherein the phase shift is detectable via the first port.

The utility model provides a self-powered intelligent water meter based on electromagnetic power generation. The self-powered intelligent water meter comprises a first built-in cavity, a second built-in cavity, a water inlet and a water outlet, the first built-in cavity and the second built-in cavity are connected through a bolt, the water inlet is communicated with the first built-in cavity, and the water outlet is communicated with the second built-in cavity. According to the utility model, the electric signal generated by the coil is utilized, the self-power supply technology and the self-sensing technology are combined, and multiple functions are realized through the simple structure; a switch control mode is adopted in the power supply management system, so that voltage and current are only used when needed, and no electric energy is consumed in other time; the power management circuit realizes a fully-automatic switching function through battery voltage detection, so that the whole system comprises the wireless transmission module and can be called as a real self-powered system; the energy of the energy source is fully and efficiently utilized, so that no energy loss exists in the energy conversion and distribution process.

This invention discloses a device for detecting and clearing ice and snow debris from power lines, comprising five parts: a crawling mechanism, an obstacle-crossing and clearing mechanism, an eddy current heating device, an autonomous power-collecting device, and a drone docking and flight device. The autonomous power-collecting device includes an electromagnetic power-collecting device and a pantograph contact power-collecting device. The crawling device and the eddy current heating device are located inside an openable structure, while the outside of the openable structure is connected to the electromagnetic power-collecting device and the obstacle-crossing and clearing mechanism. Drone docking and flight devices are located on both sides of the crawling device, with the pantograph contact power-collecting device placed on top of the drone docking and flight devices. A main control unit is located between the crawling device and the electromagnetic power-collecting device. This invention solves the problem that traditional mechanical clearing methods easily damage power lines and accelerate wear. Simultaneously, this invention also addresses the safety hazards faced by existing clearing equipment and personnel, as well as the problem of short single-operation time due to battery performance limitations.

The invention provides a magnetic force enhanced vibration energy collection device and method. The magnetic force enhanced vibration energy collection device comprises a piezoelectric power generation module and an electromagnetic power generation module, wherein the piezoelectric power generation module comprises a piezoelectric high-frequency beam, a metal low-frequency beam, a stop block and a first permanent magnet; the electromagnetic power generation module comprises a second permanent magnet, a coil, a magnetic conductive material and a coil shaft, the coil shaft is arranged in the coil, the magnetic conductive material is located in a center hole of the coil shaft, and the coil is arranged around the magnetic conductive material. Aiming at the problems of narrow working frequency band and low energy output of a vibration energy collector, two modes of collision frequency raising and frequency expanding and magnetic force frequency raising and frequency expanding are combined in one piezoelectric energy collecting module, and meanwhile, an electromagnetic power generation module is introduced. Therefore, the energy conversion efficiency and the overall generating capacity are improved, energy collection in the overall wide frequency range is achieved, low-frequency vibration energy with the wide change range in the environment can be effectively collected and converted into electric energy, and power is supplied to wireless sensing nodes.

The present application belongs to the technical field of grid-forming converter control, in order to solve the problem that the existing control strategy is difficult to balance the transient stability and grid support capability, a hybrid synchronization control method and system considering transient stability and grid support are proposed, when the grid-forming converter is detected to have transient instability risk, a grid-following control branch based on a first-order phase-locked loop is introduced in parallel on the basis of the original grid-forming virtual synchronous machine control loop; in the initial stage of the fault, by adjusting the gain proportional coefficient, the equivalent active power reference value is reduced to zero, so as to block the active power injection and minimize the acceleration area; after a preset initial time period, by dynamic adjustment, the equivalent active power reference value tracks the current electromagnetic power in real time, while continuing to suppress the power angle oscillation, the grid support capability of the converter is effectively restored.

The invention belongs to the technical field of double-fed wind turbine generator virtual quantity regulation and control, and particularly relates to a double-fed wind turbine generator virtual inertia control method based on dynamic power tracking. Comprising the following steps: compiling a maximum power point tracking database under different wind speed conditions and different fan rotating speed conditions; the frequency change amplitude of the system is detected, and MPPT curve adjustment is carried out when the frequency drops or climbs and exceeds a set per unit value; when the system frequency drops, the MPPT curve is moved to the left side, the electromagnetic power output of the generator set is increased, and the kinetic energy of a rotor is released to participate in inertial frequency response; when the system frequency climbs, the MPPT curve is moved to the right side, electromagnetic power output of the generator set is reduced, and electric energy is absorbed and converted into rotor kinetic energy to participate in inertial frequency response; and after the inertial response is completed, the fan gradually returns to the optimal MPPT output point at the current wind speed. The inertia response link is added in the control module of the DFIG wind turbine generator, so that the fan can quickly respond to the system frequency change.

The present invention discloses a frequency up-conversion piezoelectric-electromagnetic hybrid energy collector for ultra-small displacement input, including a flexible amplification mechanism, a transmission mechanism, and a power generation mechanism; the flexible amplification mechanism includes two straight beam flexible hinges, two semicircular flexible hinges, a symmetrical flexible hinge, and corresponding rigid connection components and support rods; the transmission mechanism includes a ball screw, a one-way bearing, a gear pair, a seat bearing, and a corresponding transmission shaft; the two components of the power generation mechanism both use frequency up-conversion technology, one part is an electromagnetic power generation mechanism composed of a magnet on the edge of the flywheel and an induction coil on the support plate; the other part is a piezoelectric mechanism composed of a piezoelectric cantilever beam clamped on the support rod and a toggle block embedded in the ball screw nut. The present invention integrates electromagnetic-piezoelectric hybrid power generation technology, realizes bidirectional and efficient recovery and storage of vibration energy with low gap loss under micro-displacement input, and has broad application prospects.

The invention discloses an electromagnetic hybrid wave energy collection device and method, and belongs to the technical field of ocean wave energy collection and extraction, and the electromagnetic hybrid wave energy collection device comprises a floating ball assembly, a transmission assembly, an electromagnetic power generation assembly and a friction power generation assembly. The floating ball assembly is matched with the water surface, and mechanical energy generated when waves drive the rotating rod and the supporting and fixing rod to rotate can be efficiently captured; then the mechanical energy is transmitted to the electromagnetic power generation assembly and the friction power generation assembly on the two sides through the transmission assembly, the electromagnetic power generation assembly and the friction power generation assembly are promoted to synchronously generate electric energy, the synergistic effect of electromagnetic power generation and friction power generation is achieved, and the wave energy collection efficiency and the adaptive capacity to different wave conditions are remarkably improved; the bimodal structure gives consideration to high-power output and high-sensitivity detection and adapts to a complex marine environment, meanwhile, the floating ball assembly and the two power generation assemblies are arranged at intervals, mutual interference between the assemblies is reduced, and the operation stability of the device is guaranteed.

The invention discloses a swing reactance parameter calculation method applied to a PSS and a related device, and the method comprises the steps: monitoring the variable quantity and the corresponding time difference of an electromagnetic power signal inputted into the PSS, and obtaining the actual variable quantity and the actual oscillation period of the electromagnetic power; calculating actual swing reactance based on the actual oscillation period and a preset swing reactance formula to obtain an actual swing reactance value; and if the peak-to-peak value calculated according to the actual variation of the electromagnetic power is greater than a threshold value, selecting an actual swing reactance value, and if not, retaining an initial default value. According to the method and the device, the technical problem of influence on the damping effect of the PSS caused by lack of accuracy and reliability of the calculated rotating speed of the unit due to the fact that the setting problem of the swing reactance parameter is not considered in a targeted manner in the prior art can be solved.

The application provides a flexible direct current system frequency control method, device, equipment and readable storage medium, which is suitable for a water and electricity through a flexible direct current pure island sending system. When it is judged that the AC voltage of the flexible direct current sending end converter station of the system exceeds the preset first threshold value, the application can judge whether the AC fault of the flexible direct current transmission system is removed. If the AC fault is removed, the frequency reference value of the sending end converter station control system is increased from an initial value to a preset second threshold value. After the frequency reference value of the sending end converter station control system is maintained for a preset first time, the frequency reference value of the sending end converter station control system of the flexible direct current transmission system is reduced from the preset second threshold value to the initial value according to the preset frequency reference value adjustment condition. The method can reduce the overshoot of the generator electromagnetic power during the recovery of the sending end AC system fault of the flexible direct current transmission system, reduce the impact on the sending end converter station of the flexible direct current transmission system, and is beneficial to maintaining the transient stability of the system.

The invention relates to a testing area combined type concrete quality detection rebound apparatus, which comprises a plurality of testing units arranged in parallel and used for testing a plurality of point positions in batches, each testing unit comprises a shell, a pull rod arranged in the shell in a sliding manner, a bouncing rod fixedly connected with the pull rod, a bouncing hammer and a bouncing tension spring, and a sealing pipe is also arranged in the shell. According to the combined type electromagnetic power concrete quality detection rebound apparatus, the rebound apparatus can be carried through an excavator, a bucket of the excavator is replaced by the rebound apparatus, bouncing tests of multiple point positions of each high-altitude detection area can be rapidly completed, the function of continuously launching bouncing rods can be achieved, manual work is not completely relied on, and the working efficiency is improved. Labor intensity of detection personnel is reduced, high-altitude scaffold building is not needed, and the instrument is flexible and accurate in operation and positioning and good in safety.

The invention belongs to the field of mechano-electronics and industrial automation control, and particularly relates to an industrial-grade electromagnetic boosting arm device with a fault self-diagnosis and passive safety mode, which comprises a loading seat integrated with a circuit board. The device comprises an electromagnetic driving execution module, a multi-mode sensing acquisition module, a self-adaptive signal conditioning module, a real-time fault diagnosis module, a passive safety decision module and a dynamic trajectory planning module. Through the dynamic filtering and phase locking technology of the adaptive signal conditioning module, the interference of the noise of the power switch on the signal of the rotary transformer is effectively suppressed, and the accuracy of fault diagnosis and the positioning precision of the device are remarkably improved. A multi-dimensional parallel diagnosis mechanism of the real-time fault diagnosis module can identify potential faults of a motor, a transmission chain and a sensor in an early stage, and device performance deterioration caused by fault accumulation is avoided.

An infrared automatic switching light filter with wireless power supply includes: a housing; a light filter carrier plate slidably provided in the housing; and a driving mechanism configured to drive the light filter carrier plate to slide. The electromagnetic power mechanism includes a bracket; a coil is wound around outside the bracket along an axial direction of the bracket; the bracket is provided with conductive elastic pieces respectively connected to both ends of the coil; end portions of the conductive elastic piece are respectively provided with protrusion in contact with and connected to an external power supply apparatus; the electromagnetic power mechanism further includes a U-shaped magnetic conductive member penetrated through the bracket; and the transmission mechanism includes a rotary magnetic member provided between two ends of the U-shaped magnetic conductive member.