Patents
Literature
Patsnap Eureka AI that helps you search prior art, draft patents, and assess FTO risks, powered by patent and scientific literature data.

142 results about "Ac frequency" patented technology

In electricity, alternating current (AC) occurs when charge carriers in a conductor or semiconductor periodically reverse their direction of movement. Household utility current in most countries is AC with a frequency of 60 hertz (60 complete cycles per second), although in some countries it is 50 Hz.

Alternating current and direct current micro-grid layered distributed control method and system

The invention relates to the technical field of micro-grid control, and discloses an AC / DC micro-grid layered distributed control method and system, and the method comprises the steps: obtaining a DC voltage outputted by a distributed power supply in a DC micro-grid and an AC frequency outputted by a distributed power supply in an AC micro-grid, and carrying out the normalization processing; according to the voltage normalization value and the frequency normalization value, a finite time consistency algorithm is adopted to calculate a primary active power reference value of the interconnected converter; compensating the primary active power reference value according to a distributed secondary controller to obtain a secondary active power reference value; and generating a control signal of each interconnected converter according to the secondary active power reference value. Through hierarchical distributed control, the purposes that the total power sent by the direct current micro-grid and the alternating current micro-grid is proportionally distributed according to respective rated capacities and the active power transmitted by all the interconnected converters is proportionally distributed according to the transmission capacities are achieved, and the operation safety and stability of the alternating current and direct current micro-grid are effectively improved.
Owner:LISHUI POWER SUPPLY COMPANY OF STATE GRID ZHEJIANG ELECTRIC POWER

Blast furnace top feeding winch control system

PendingCN119284784AFast dynamic responseImprove overload capacityWinding mechanismsConvertersLoop control
The invention discloses a blast furnace top feeding winch control system which comprises four multi-transmission high-performance motion control frequency converters, and wire inlet structures of the transmission high-performance motion control frequency converters specifically comprise a system wire inlet structure A, a system wire inlet structure B and a system wire inlet structure C, the A system wire inlet structure comprises an A system wire inlet cabinet, an A system first rectifier cabinet, an A system second rectifier cabinet, an A system first inverter cabinet, an A system second inverter cabinet and an A system resistor cabinet; and B, a system wire inlet structure. A winch control system is optimized, a PLC alternating-current variable-frequency speed regulation mode is adopted, the speed dynamic response is high, the overload capacity is large, operation is safe and reliable, and the PLC self-control technology, the position encoder measurement technology, the large-scale variable-frequency speed regulation dragging technology and the intelligent master controller are organically combined and applied; and the faults of galloping, sliding, derailing and the like of the skip car in operation are reduced through double closed-loop control and multi-section speed control of a current loop and a speed loop of the motor.
Owner:SINOSTEEL XIAN MACHINERY

Electrochemical monitoring system adjustment

In an example, an electrochemical monitoring system for determining one or more parameters of interest of an electrochemical cell can include measurement circuitry, which can be configured to obtain, for a plurality of specified alternating current (AC) frequencies: (1) a first AC voltage measurement across nodes which can be coupleable to the electrochemical cell, and (2) a second AC voltage measurement across a sensing impedance which can be elicited in response to the AC stimulus. The sensing impedance can be coupled in series with the electrochemical cell. The electrochemical monitoring system can also include a controller circuit, which can be configured to jointly estimate model parameters corresponding to an equivalent circuit model (ECM) of a combination of the electrochemical cell and the sensing impedance, such as using the first and second AC voltage measurements for the plurality of specified AC frequencies.
Owner:ANALOG DEVICES INC

Horticultural lighting systems, devices, and methods

A horticultural lighting device includes an LED array with multiple LED channels of different wavelengths, each having one or more LEDs. A voltage regulator supplies at least one LED channel with a constant voltage. A processor produces a PWM signal for a driving circuit coupled with the LED channels. In some cases the processor operates a tuning circuit to adjust the constant voltage thereby adjusting an intensity of the one or more LEDs of the one or more LED channels. A lighting system has multiple lamps, each with a zero cross detector that generates a timing signal based on an AC input signal. The PWM signal of each lamp has a frequency that is a multiple of the AC frequency. A method for lighting a facility includes generating a light recipe based on sensor data with an AI engine with one or more neural networks.
Owner:SMARTGRO BIOENGINEERING INC

Battery module having multiple fire safety features, and applications thereof

Provided is a battery module and battery rack having enhanced fire safety features. The battery module includes a swelling / pressure sensor that detects swelling of a battery cell. An output signal of the sensor is used to halt operation of a battery rack / battery system containing the battery module and prevent charging and discharging of the battery module. In an embodiment, the battery module uses an AC-to-AC power supply to provide AC frequency power for balancing battery cells of the battery module. In an embodiment, the battery rack includes an internal water fire suppression system that provides battery cooling in the event of a battery cell fire to prevent the spread and / or reigniting of the fire.
Owner:VLTRU TECHNOLOGIES INC

Method and device for acquiring input current of single-phase alternating-current frequency converter and frequency converter

The invention discloses a single-phase AC frequency converter input current obtaining method and device and a frequency converter, and the method comprises the steps: obtaining a DC bus voltage in a single-phase AC frequency converter, determining a load current and a bus capacitor ripple current according to the DC bus voltage, and determining a DC side current according to the load current and the bus capacitor ripple current; and determining the input current in the single-phase alternating-current frequency converter according to the direct-current side current. According to the application, the input current in the single-phase alternating current frequency converter can be obtained through the circuit parameters which can be directly obtained in the single-phase alternating current frequency converter, and the cost of obtaining the input current of the single-phase alternating current frequency converter can be greatly reduced.
Owner:GD MIDEA HEATING & VENTILATING EQUIP CO LTD +1

Power coordination control method for AC / DC hybrid power distribution system based on solid-state transformer

The present invention is a power coordination control method for an AC / DC hybrid power distribution system based on a solid-state transformer. The system includes a main grid, a solid-state transformer and an AC / DC microgrid. The solid-state transformer is a three-level structure of a low-voltage level, an isolation level and a medium-voltage level. The control method is composed of a low-voltage level, an isolation level, a medium-voltage level control strategy and a pre-synchronization control strategy. The low-voltage level associates the low-voltage AC frequency and the low-voltage DC voltage representing the power state of the AC / DC microgrid, and realizes power coordination between AC / DC microgrids without communication. The isolation level and the medium-voltage level establish a connection between the medium-voltage AC frequency and the low-voltage DC voltage, and realize the power exchange between renewable energy and the medium-voltage AC bus according to its own state. The pre-synchronization control strategy enables seamless switching of various modes. Under the premise of no communication and no switching control strategy, the present invention realizes stable operation and seamless switching of various modes, improves system reliability, and enhances the level of renewable energy consumption.
Owner:TAIYUAN UNIVERSITY OF TECHNOLOGY

Sending-end bipolar converter control method and device and computer readable storage medium

The invention belongs to the technical field of flexible direct-current power transmission, and particularly relates to a sending-end bipolar converter control method and device and a computer readable storage medium. When the power requirements of receiving end power grids connected with receiving end current converters of two flexible direct current transmission poles are inconsistent and only one pole of receiving end power grid has a clear active power requirement, a control device of a sending end current converter of a pole where the receiving end current converter connected with the receiving end power grid with the clear active power requirement is located adopts PI control to calculate a frequency difference value; the control device of the transmitting-end converter of the other pole adopts active power-alternating current frequency droop control to realize active power differential control of the two-pole converter, so that the active power of the transmitting-end two-pole converter is distributed as required according to the active power requirement of the receiving-end power grid; flexible configuration of new energy active power is realized, a new energy station is prevented from being urgently cut off, and the effective utilization rate of new energy is improved.
Owner:XJ ELECTRIC CO LTD +1

Thermal impedance monitoring process for power modules

A thermal impedance monitoring process for a power module of a power converter for converting a DC current to an AC current, or converting an AC circuit to a DC current, where a semiconductor dissipates asymmetric losses between two half cycles of an AC frequency f of the AC current, said power module comprising at least a semiconductor die, a semiconductor die is attached to a stack of materials of layers for heat dissipation and / or electrical connection thereof, the process comprising: sampling and measuring a signal related to a junction temperature Tj of the semiconductor die at a frequency higher than twice the AC frequency of the AC current, calculating a duration [Delta] t = tTjmax-tTjmin between a moment tTjmax at which the junction temperature of the semiconductor die is at a maximum value and a moment tTjmin at which the junction temperature is at a minimum value in one cycle of the AC current, and storing the duration [Delta] t in a memory, repeating the step of sampling and measuring said signal and the step of calculating said duration at different times tx = t0 to tm during the operating life of the power module to provide a series of durations [Delta] t0 to [Delta] tm, and comparing the values of said durations [Delta] t0 to [Delta] tm for monitoring the evolution of said duration [Delta] t, and determining the evolution of the degradation of the thermal impedance of the power module.
Owner:MITSUBISHI ELECTRIC CORP

Double-end frequency cooperative control and stability analysis method of flexible direct current power transmission system

The invention discloses a double-end frequency cooperative control and stability analysis method for a flexible direct-current power transmission system, and the method comprises the steps: firstly building a linear mapping relation between the direct-current voltage of an inverter station and a receiving-end alternating-current system, and then building a quantitative relation between the direct-current voltage of a receiving-end alternating-current frequency and the direct-current voltage of a rectifier station; and then establishing a flexible DC system double-end AC frequency system control relationship, further establishing a system linearization model after double-end frequency cooperative control is input, and finally performing system stability analysis under frequency cooperative control. According to the frequency coupling control method, the overall frequency stability of the system can be effectively improved through power mutual assistance between the sending end system and the receiving end system.
Owner:ZHEJIANG UNIV +1

Three-bus AC / DC micro-grid architecture

The invention discloses a three-bus AC / DC micro-grid architecture, which comprises a low-energy-carrying DC bus, and a small-power photovoltaic power generation unit, a small-power wind power generation unit, a small-power fuel cell unit and a small-capacity energy storage unit which are connected, and is characterized in that the nominal voltages of the low-energy-carrying DC bus are 12V, 24V and 48V, and the low-energy-carrying DC bus is used for supplying power to a low-voltage DC load; the high-power photovoltaic power generation unit, the high-power wind power generation unit, the high-power fuel cell unit and the high-capacity energy storage battery are connected, the nominal voltage of the high-energy-carrying direct-current bus is 375V, 400V, 600V, 750V and 900V, and the high-energy-carrying direct-current bus is used for supplying power to a high-power direct-current load; the system comprises an alternating current bus, an accessed mains supply, an internal combustion generator set and an energy storage converter, the voltage of the alternating current bus is 220 / 380V, the frequency of the alternating current bus is 50Hz, and the alternating current bus is used for supplying power to an alternating current load; the low-energy-carrying direct-current bus and the 220V alternating-current bus form a low-power micro-grid, the high-energy-carrying direct-current bus and the 380V alternating-current bus form a high-power micro-grid, and the low-power micro-grid and the high-power micro-grid are connected in parallel through the 380V alternating-current bus to form a three-bus micro-grid framework of the low-energy-carrying direct-current bus, the high-energy-carrying direct-current bus and the alternating-current bus. According to the invention, the power supply guarantee flexibility in emergency rescue, field operation and other scenes is improved.
Owner:ARMY ENG UNIV OF PLA

Distributed power-supply management apparatus and power distribution system

Provided is a distributed power-supply management apparatus (31) for managing one or more distributed power supplies. Each of the one or more distributed power supplies is connected to a power grid and operates as a voltage source. The relationship between the frequency and power of each of the one or more distributed power supplies has a droop characteristic, and is adjusted such that a command value for frequency (Fref) and a command value for power (Pref) correspond to each other. The distributed power-supply management apparatus (31) is provided with: an AC-frequency collecting unit (313) that collects information on the AC frequency of the power grid, and on the basis of the collected AC-frequency information, determines a representative value (Fmeasure) for the AC frequency; and a frequency command-value generating unit (315) that on the basis of the representative value for the AC frequency, generates respective frequency command values (Fref) for the one or more distributed power supplies.
Owner:MITSUBISHI ELECTRIC CORP

Control system for enhancing inertia supporting capability of flexible direct-current power transmission system

The invention relates to the technical field of flexible direct-current power transmission, and provides a control system for enhancing the inertia supporting capacity of a flexible direct-current power transmission system in order to solve the problem that a conventional grid-following type flexible direct-current power transmission system is poor in power system frequency supporting capacity. A real-time linkage mechanism among the alternating-current frequency, the direct-current voltage and the power grid voltage of the sending-end converter station is established, and the frequency decoupling problem of the sending-end converter station and the receiving-end converter station under conventional network following type control is solved. A direct-current voltage signal of the flexible direct-current power transmission system is transmitted to a new energy power supply side, a conventional method for observing the frequency of a power grid by using a phase-locked loop is replaced, the output power of the new energy power supply is adjusted by using the direct-current voltage signal, and a frequency supporting function for the power grid is realized. Inertia support and frequency adjustment control are added on a new energy power supply, and an inertia support coefficient and a frequency adjustment coefficient are adjusted in real time according to a direct current voltage signal of the direct current power transmission system, so that the inertia support capability of the flexible direct current power transmission system is enhanced.
Owner:ELECTRIC POWER RES INST OF GUANGDONG POWER GRID CO LTD +1

System and method for collecting and sending out land low-frequency new energy

The embodiment of the invention provides a land low-frequency new energy collecting and sending-out system and method, and the system comprises a low-frequency new energy power generation module, a low-frequency collecting module, a low-frequency power transmission system, and a low-frequency grid-connected module, the low-frequency new energy power generation module is connected with a low-frequency collecting switching station of the low-frequency collecting module through a plurality of low-frequency circuit breakers, and the low-frequency power transmission system is connected with the low-frequency grid-connected module. The low-frequency collection module is connected with a low-frequency overhead line of the low-frequency power transmission system through a low-frequency circuit breaker, and the low-frequency overhead line in the low-frequency power transmission system is connected with a low-frequency transformer in the low-frequency grid-connected module through a low-frequency circuit breaker. A low-frequency transformer in the low-frequency grid-connected module is connected with a power frequency main power grid through an AC-AC frequency converter and a power frequency circuit breaker; according to the invention, large-scale land new energy can be collected and sent out remotely, new energy consumption is promoted, and the power grid efficiency is improved.
Owner:ELECTRIC POWER RESEARCH INSTITUTE OF STATE GRID JIBEI ELECTRIC POWER CO LTD +2

Vibronic measuring system

A measuring system includes a vibration-type transducer and electrically coupled measuring system electronics unit for controlling the transducer and evaluating vibration measurement signals provided by the transducer. The exciter arrangement has a vibration exciter which is positioned and aligned such that a drive offset is no more than 0.5% of the tube length. The measuring system electronics are configured to supply electrical power to the vibration exciter by means of an electrical drive signal having a temporally variable electrical current and to provide the drive signal at least intermittently with a sinusoidal second useful current having a second AC frequency, in order to monitor a quality of the measured substance based upon a corresponding second useful signal component of at least one of the vibration measurement signals.
Owner:ENDRESS HAUSER FLOWTEC AG

Parallel power control method for bidirectional interface converter of alternating-current and direct-current hybrid micro-grid

The invention provides a parallel power control method for a bidirectional interface converter of an AC / DC hybrid micro-grid, and the method comprises the steps: adding an inertia control link and a capacity distribution link into an active control loop of the parallel bidirectional interface converter; according to the alternating current side frequency deviation and the direct current side voltage deviation of the parallel bidirectional interface converter, an active power transmission reference value of each bidirectional interface converter is calculated through inertia control and capacity allocation links; and the active power transmission reference value of each bidirectional interface converter is sent to a power current control ring to obtain a signal for driving a switch in the three-phase bridge type conversion circuit. Power distribution is realized through inertia control and capacity distribution links, the control convenience and reliability of the parallel bidirectional interface converter are improved, the circulating power of the parallel bidirectional interface converter is solved, the complex calculation of control parameters of the parallel bidirectional interface converter is reduced, the power balance state of the parallel bidirectional interface converter is formed, and the reliability of the parallel bidirectional interface converter is improved. And meanwhile, the dynamic response of alternating-current frequency and direct-current voltage and current is improved.
Owner:ZHENJIANG POWER DESIGNING INST CO LTD

A hierarchical distributed control method and system for AC-DC microgrids

The present invention relates to the field of microgrid control technology, and discloses a hierarchical distributed control method and system for an AC-DC microgrid, including obtaining the DC voltage output by distributed power sources in the DC microgrid and the AC frequency output by distributed power sources in the AC microgrid, and performing normalization processing; according to the voltage normalization value and the frequency normalization value, adopting a finite-time consensus algorithm to calculate the primary active power reference value of the interconnected converters; compensating the primary active power reference value according to a distributed secondary controller to obtain a secondary active power reference value; and generating control signals for each interconnected converter according to the secondary active power reference value. Through hierarchical distributed control, the present invention realizes the goal of proportional distribution of the total power generated by the DC microgrid and the AC microgrid according to their respective rated capacities, and proportional distribution of the active power transmitted by all interconnected converters according to the transmission capacity ratio, effectively improving the safety and stability of the operation of the AC-DC microgrid.
Owner:LISHUI POWER SUPPLY COMPANY OF STATE GRID ZHEJIANG ELECTRIC POWER

A method and apparatus for detecting islands

This application discloses an islanding detection method and apparatus. The method includes: monitoring the AC frequency of an inverter, which fluctuates within a preset range when the inverter is in normal control mode; when the instantaneous offset value of the AC frequency exceeds the preset range, the frequency before the instantaneous offset is taken as the first frequency; if the frequency in the first frequency data within a first preset time range is only greater than or only less than the first frequency, the AC frequency at the end of the first preset time is taken as the second frequency; continuously adjusting the output power of the inverter based on the change of the current AC frequency; and when the frequency in the second frequency data within a second preset time range is only greater than or only less than the second frequency, the inverter can be promptly instructed to report the islanding status. By using a two-step judgment method, the method distinguishes between islanding and normal load switching, avoiding the inverter actively adjusting the system voltage or frequency and improving the accuracy of islanding detection.
Owner:HUAWEI DIGITAL POWER TECH CO LTD

A method of controlling an energy storage system

This application provides a control method for an energy storage system, comprising: determining the state parameters corresponding to each individual battery cell; determining a multi-dimensional control factor corresponding to each individual battery cell based on different state dimensions indicated by the state parameters at preset calculation cycles; sorting multiple individual batteries cells according to the charge / discharge state of the energy storage system and the multi-dimensional control factor; determining the output demand voltage corresponding to the energy storage system based on the peak reference voltage and AC frequency corresponding to the energy storage system; and controlling the access state of each individual battery cell in the next AC cycle by applying the nearest level approximation method based on the sorting result, the output demand voltage, and the maximum supply voltage corresponding to each individual battery cell in the next AC cycle. This application controls the energy storage units connected to the charge / discharge circuit of the energy storage system and their access time through multi-dimensional control factors calculated from multiple dimensions, thereby achieving full utilization of the energy of the energy storage units.
Owner:SHANGHAI PYLON TECH CO LTD

An energy-saving optimization control system for an AC frequency converter of a water pump

PendingCN122630398AFrequency changerWater use
The application discloses a kind of water pump AC frequency converter energy-saving optimization control system, it is related to water pump energy-saving control technical field;Including: database, identification perception module, operation optimization module and control feedback module.Database acquires water pump operating parameter, and based on this and calculates lift, water pump efficiency and load rate;Identification perception module is based on lift, water pump efficiency and load rate deviation analysis constructs fusion deviation curve, and based on this obtains judging index to analyze curve area, to identify inefficient operation scene;Operation optimization module determines target flow, target lift according to end water demand and pipe network pressure demand, and obtains target frequency in combination with water pump similarity law and efficiency, lift deviation correction;Control feedback module implements frequency conversion control according to target operating parameter, and real-time feedback and secondary correction are carried out to execution result, form closed-loop optimization control, improve energy efficiency identification ability under low load condition, reduce water pump operating energy consumption.
Owner:TAIZHOU SHENNENG ELECTRIC

Power supply device and temperature measuring method thereof

A power supply device comprises a busbar, a circuit measurer, a temperature sensor and an operational circuit. The busbar is coupled to the inverter and the motor. The temperature sensor is used for measuring an initial temperature in an initial state. The circuit measurer is used for measuring voltage, current and alternating current frequency on the busbar. The arithmetic circuit is coupled to the circuit measurer and the temperature sensor. The operational circuit is configured to: calculate a resistance signal based on the AC frequency; calculating a first transient power of the busbar based on the current on the busbar and the resistance value signal; calculating a first temperature rise value of the busbar based on the first transient power; and adding the initial temperature and the first temperature rise value to obtain a first transient ideal temperature of the busbar. The invention further relates to a busbar temperature measuring method.
Owner:DELTA ELECTRONICS INC(CN)

A device for protecting a voltage transformer from ferroresonance phenomena

The utility model relates to electrical engineering and can be used to protect electromagnetic voltage transformers from ferroresonant oscillations occurring in voltage transformers in distribution networks with a voltage class of 6-10 kV, alternating current with a frequency of 50 Hz with an isolated neutral.In a device for protecting voltage transformers from ferroresonance phenomena, designed with the possibility of connecting to two terminals of auxiliary secondary windings of three single-phase transformers connected in an open-delta circuit, containing a series-connected RTS thermistor, a damping resistor and an electronic switching circuit with a threshold switching characteristic, which includes a switching element in the form of a triac, the control electrode of which is connected to a control circuit including a dinistor, two resistors and a capacitor, the control electrode of the triac is connected to the control circuit through a normally closed controlled key, the RTS thermistor is equipped with a temperature sensor connected to the controlled key, and the dinistor is selected to be symmetrical.Technical result: increasing the effective operating time of a device for protecting voltage transformers from ferroresonance phenomena in the presence of modes in the network accompanied by prolonged exposure to single-phase short circuits to ground by ensuring restoration of the original operating mode. 2 fig.
Owner:ОБЩЕСТВО С ОГРАНИЧЕННОЙ ОТВЕТСТВЕННОСТЬЮ НЕВСКИЙ ТРАНСФОРМАТОРНЫЙ ЗАВОД ВОЛХОВ (ООО НТЗ ВОЛХОВ )

ARM microprocessor operation equipment for AC frequency converter

The utility model relates to an ARM microprocessor operation device for an alternating current frequency converter, and belongs to the technical field of alternating current frequency converter matching equipment.The ARM microprocessor operation device comprises an installation shell, a box door is hinged to the front face of the installation shell through hinges, and a wiring assembly used for wire arrangement is installed on the inner side of the installation shell; a ventilation assembly used for ventilation and heat dissipation is installed on the inner side of the installation shell, a water cooling assembly used for water cooling is installed on the outer side of the installation shell, a control panel used for control is fixedly installed on the outer side of the box door, and an alternating current frequency converter body is installed on the inner side of the installation shell. The inner side of the installation shell is provided with an ARM microprocessor main body used for controlling the AC frequency converter main body and an abnormal protection module used for detecting abnormal current. According to the ARM microprocessor operation equipment for the alternating current frequency converter, the equipment cannot be directly stopped when the current is unstable due to the abnormal phenomenon of the main power supply, the buffer time is provided for the equipment, and the heat dissipation effect can be ensured on the premise that the equipment is additionally arranged.
Owner:HUNAN JIWEI ELECTRONICS SCI & TECH

A comprehensive electrical prospecting method and device

A comprehensive electrical prospecting method and device provided by the present invention, the method comprising: inputting an alternating current frequency signal with a preset bandwidth into the geological object to be measured in a frequency sweep manner, receiving the voltage data recorded by the measuring electrodes, and obtaining an amplitude-frequency response curve; finding the frequency corresponding to the amplitude attenuation position according to the amplitude-frequency response curve to obtain the response frequency of the geological object to be measured; obtaining the distribution characteristics of the water-richness of the geological object to be measured according to the difference between the response frequency of the geological object to be measured and the response frequency of a single medium; the present invention determines the distribution characteristics of the water-richness of coal and rock strata according to the difference between the response frequency of the geological object to be measured and the response frequency of a single medium. At the same time, by means of frequency sweep, the frequencies required for detecting the medium are covered, avoiding the omission situation existing in the current alternating current electrical method, so as to ensure the accuracy of the underground exploration results.
Owner:FUZHOU HUAHONG INTELLIGENT TECH

Automatic control method and device for acidification process of medicinal sodium chloride

The invention belongs to the technical field of sodium chloride production, and particularly relates to an automatic control method and device for an acidification process of medicinal sodium chloride. The method comprises the following steps: transmitting a brine acid adding pH value and a metering pump frequency conversion signal to a DCS (Distributed Control System), and tracking in real time by the DCS; detecting the pH value of the brine to be subjected to acid adjustment through a static mixer; calculating the required acid adding amount; the DCS outputs a 4-20mA direct current signal in direct proportion to the acid adding amount to the alternating current frequency converter; the AC frequency converter converts the control signal into a corresponding frequency to control the metering pump; the purpose of controlling the acid adding amount is achieved by controlling the rotating speed of the metering pump; and controlling the pH value of the brine within a qualified range, and entering a subsequent process. According to the invention, sustainability, monitorability and high-precision control of the brine acidification process in the production process of the medicinal sodium chloride can be realized, the pH regulation and control precision can reach + / -0.3, the pH uniformity of refined brine and the stability of the production process and the product quality are improved, the safety of the working environment is improved, and the labor cost is reduced.
Owner:TIANJIN HAIGUANG PHARM CO LTD

Battery module with integrated battery management system with expansion / pressure detector and application thereof

A battery module and a battery rack with enhanced fire safety features are provided. The battery module includes an expansion / pressure sensor that detects expansion of a battery cell. The output signal of the sensor is used to stop operation of a battery rack / battery system containing the battery module and to prevent charging and discharging of the battery module. In an embodiment, the battery module provides AC frequency power using an AC-to-AC power supply to balance battery cells of the battery module. In an embodiment, the battery rack includes an internal water fire extinguishing system that provides battery cooling in the event of a battery cell fire to prevent fire spread and / or reignition.
Owner:VOLTARU TECHNOLOGY CO LTD

Servo system for ship towing winch and control method thereof

The invention discloses a servo system for a ship towing winch and a control method of the servo system. The servo system comprises a rectifying circuit, a three-phase full-bridge circuit, a braking circuit, a DSP control circuit, an output capacitor C, a brake control circuit and a rotary transformer decoding circuit. According to the servo driver, full electrification of releasing, recycling and zero-speed working condition maintaining of the ship winch is achieved, compared with a hydraulic driving device of a traditional winch, the defects that a hydraulic system is complex in structure, large in size and difficult to maintain are overcome, and an electric driving system is high in control precision, simpler to achieve and more convenient to operate. Compared with conventional alternating-current variable-frequency electric drive of an existing winch, servo drive is more suitable for the low-speed large-torque working condition, efficiency is higher, and cooperation of a PLC is not needed. Compared with a traditional speed loop and current loop control method, the control method for four-quadrant operation of the servo driver enables the winch to have an energy consumption braking function, and meanwhile the safety of the towing winch under the extreme working condition is guaranteed by being matched with a brake of the motor.
Owner:GUIZHOU AEROSPACE LINQUAN MOTOR CO LTD

Sparse modular multilevel matrix converter topology, design and control method

The invention provides a sparse modular multilevel matrix converter topology, a design method and a control method. The topology has three-phase symmetry of an input side and an output side. The design method aims at reserving the conventional M3C function and performance and reducing the cost, and comprises the following steps: setting the input side alternating current frequency and the output side alternating current frequency of a matrix converter to be in an integer frequency division relationship; through a control mode of phase coordination on two sides, the utilization rate of direct-current voltage is improved, and the modulation wave amplitude of each bridge arm is reduced; and determining that the number of the bridge arm sub-modules is less than that of the conventional M3C based on the modulation wave amplitude. Through the phase coordination technology, the number of the bridge arm sub-modules is reduced on the basis of reserving the conventional M3C function and performance, so that the cost is reduced, and the operation efficiency is improved to a certain extent.
Owner:SHANGHAI JIAOTONG UNIV

Frequency sensing and rapid supporting method for wind power multi-terminal flexible direct current sending-out system

The invention discloses a frequency sensing and rapid supporting method for a wind power multi-terminal flexible direct current sending-out system. The method comprises the following steps that a fan side VSC control framework and a control framework and control rules of an alternating current power grid side flexible direct current converter station are constructed; an alternating-current power grid frequency-direct-current voltage-wind power plant power mapping model is constructed based on the characteristics of the converter station, and accurate sensing of the alternating-current frequency under the condition of no rapid communication is achieved; based on the mapping model, determining an improved frequency support strategy design scheme of the large-scale wind power multi-terminal flexible direct current sending-out system; and setting parameter constraint conditions for key parameters of the strategy. Accurate sensing of the alternating current frequency can be achieved under the condition of no rapid communication, the lowest frequency point after power disturbance is effectively raised, the frequency change rate is reduced, secondary falling of the frequency is avoided, meanwhile, different topological structures and line fault scenes are adapted, and safe and stable operation of an electric power system is guaranteed.
Owner:TIANJIN UNIV +1

Amorphous alloy three-dimensional wound core annealing monitoring model

ActiveCN224696608UGet loss data in real timeInhibit deteriorationBusbarLow voltage
The utility model discloses a kind of amorphous alloy three-dimensional roll iron core annealing monitoring models, comprising: support, amorphous alloy three-dimensional roll iron core, high voltage coil, low voltage coil, insulating iron hoop, ac frequency modulation power supply, magnetized busbar and power analyzer, high voltage coil and low voltage coil are set in the upper yoke portion of amorphous alloy three-dimensional roll iron core;Insulating iron hoop is used to fix amorphous alloy three-dimensional roll iron core;Magnetized busbar is supported by insulating support plate and placed in the inner frame of the iron core;Ac frequency modulation power supply is electrically connected with high voltage coil;Voltage clamp and current clamp are electrically connected with low voltage coil respectively;Power analyzer is electrically connected with the voltage clamp and current clamp.
Owner:SHENYANG UNIVERSITY OF TECHNOLOGY