113 results about "Active filter" patented technology

The invention provides a hysteresis loop analysis method for a transformer no-load loss test, and belongs to the technical field of transformers. Exciting voltage and current signals are collected in a transformer no-load state, and an active filter is used for carrying out digital filtering processing to eliminate harmonic interference; a data corresponding relation between magnetic flux density and magnetic field intensity is established through a digital integration algorithm and a magnetic field intensity calculation formula to form original hysteresis data, the original hysteresis data is processed by using a hysteresis loop optimization model, a complete hysteresis loop curve is generated, and the hysteresis loop area is calculated. According to the hysteresis loop area, the hysteresis loss power density is calculated through the iron loss calculation function, the total value of the transformer no-load loss is obtained by combining the eddy current loss calculation result, and the technical problems that the hysteresis loop reconstruction precision is not high and the complex hysteresis phenomenon cannot be adapted in the transformer no-load loss test are solved.

A high-speed, low-noise laser signal detection apparatus, comprising a low-noise linear regulated power supply and a laser detection processing module. The low-noise linear regulated power supply (01-03) comprises an isolation unit (01), a voltage regulation and filtering unit (02), and a reference unit (03). The laser detection processing module (04-09) comprises a laser light signal detection input unit (05), a bias unit (04), a differential amplification unit (07), an active filtering unit (08), and an output interface unit (09). An output end of the voltage regulation and filtering unit (02) is connected to the reference unit (03) and the laser detection processing module (04-09). The reference unit (03) is connected to the bias unit (04) and is configured to provide a reference voltage to the bias unit (04). The bias unit (04) is configured to provide a bias voltage to the differential amplification unit (07). The differential amplification unit (07) comprises a multi-stage in-phase proportional differential amplification circuit, and the active filtering unit (08) comprises a multi-order active low-pass filter. According to the high-speed, low-noise laser signal detection apparatus, the detection bandwidth of a laser signal can be expanded, the signal-to-noise ratio of high-frequency pulse measurement can be reduced, and the anti-interference characteristics of a power supply can be improved.

Wireless circuitry can include a first filter circuit configured to output signals in a first frequency range, a second filter circuit configured to output signals in a second frequency range different than the first frequency range, and a signal combiner having a first input coupled to the first filter circuit and having a second input coupled to the second filter circuit. The wireless circuitry can further include a first switchable impedance matching circuit coupled between an antenna and the first filter circuit and a second switchable impedance matching circuit coupled between the antenna and the second filter circuit. The first and second filter circuits can be active filters such as lowpass-to-bandpass conversion filters operable in different frequency bands.

Wireless circuitry can include a first filter circuit configured to output signals in a first frequency range, a second filter circuit configured to output signals in a second frequency range different than the first frequency range, and a signal combiner having a first input coupled to the first filter circuit and having a second input coupled to the second filter circuit. The wireless circuitry can further include a first switchable impedance matching circuit coupled between an antenna and the first filter circuit and a second switchable impedance matching circuit coupled between the antenna and the second filter circuit. The first and second filter circuits can be active filters such as lowpass-to-bandpass conversion filters operable in different frequency bands.

The application discloses a new energy automobile high-voltage bus temperature control active filter, and relates to the technical field of new energy automobiles, which comprises a filtering mechanism, an auxiliary mechanism is arranged in the main shell, the auxiliary mechanism comprises a micro high-pressure pump and a liquid storage tank, each liquid outlet end of the shunt pipe is communicated with a micro nozzle, a volute spring is additionally arranged between the inner wall of the circular ring and the bottom end of the disc, and a rotary joint is communicated with the top liquid outlet of the winding disc. The auxiliary mechanism can stabilize the temperature in the temperature control active filter under extreme conditions, so that the influence of the harmonic treatment effect of the temperature control active filter caused by the fact that heat is not completely discharged in time is avoided, and the use efficiency of the temperature control active filter is improved.

The invention discloses a novel elevator light curtain which comprises an all-plastic shell and a circuit board arranged in the all-plastic shell. The circuit board adopts a cascade multi-path switching module to gate a plurality of photoelectric units, and a grounding filter network is arranged at the output end of each photoelectric unit for source filtering; an active filtering buffer unit with a PNP triode as a core is introduced into a signal path, and a signal processing module comprising a four-stage operational amplifier and a gradient RC filtering network is adopted for step-by-step amplification and conditioning. Through systematic hardware circuit design, on the premise of not depending on metal shielding, internal and external electromagnetic interference is actively and multiply inhibited from the source to the terminal, meanwhile, the structure is simplified, the cost is reduced, the short circuit and failure risks possibly caused by shell grounding are thoroughly avoided, and higher reliability, environmental adaptability and economical efficiency are achieved.

The utility model discloses power electronics equipment's test and debugging technical field relates to a kind of debugging device for active filter;Including cabinet;The cabinet inside is provided with voltage regulator, control module and power module;The control module is located above voltage regulator;The cabinet side is provided with aviation plug;The power module and voltage regulator are electrically connected;The voltage regulator and aviation plug are electrically connected;The aviation plug is electrically connected with active filter and control module respectively;The active filter and mutual inductor are electrically connected;The mutual inductor and control module are electrically connected;The voltage regulator and intelligent electric meter are electrically connected;The intelligent electric meter and control module and electrically connected.The utility model can realize the quick power-on test of active filter, parameter adjustment and performance verification.

The invention discloses a design method of a three-order active filtering automatic test system, and the method comprises the steps: controlling a PXI platform through LabVIEW programming to achieve the generation of a sweep frequency signal and the collection of filtering response, and completing the signal processing, characteristic analysis and result visualization. The system integrates six core technologies, namely a modularized hardware architecture, automatic process control, frequency domain parameter precision measurement, multi-order characteristic synchronous detection, software and hardware collaborative linkage and simulation data comparison. On the basis of retaining traditional functions such as setting waveform type, amplitude, sweep frequency range, sampling rate, trigger mode, recording cut-off frequency, gain and other parameters, exponential sweep frequency accurate excitation and adaptive signal acquisition are innovatively realized, link interference is reduced through matrix switch multi-channel scheduling, a LabVIEW parallel thread and a feedback node mechanism are combined, and the adaptive signal acquisition is realized. And closed-loop analysis of amplitude-frequency / phase-frequency characteristics and real-time drawing of a Bode diagram are completed.

The application discloses a novel elevator light curtain, comprising a full-plastic shell and a circuit board arranged in the shell. The circuit board adopts a cascade multi-path switching module to select multiple photoelectric units, and a grounding filter network is arranged at the output end of each photoelectric unit to perform source filtering; an active filter buffer unit with a PNP triode as a core is introduced into a signal path, and a signal processing module containing a four-stage operational amplifier and a gradient RC filter network is adopted to perform step-by-step amplification and conditioning. The application actively and repeatedly suppresses internal and external electromagnetic interference from the source to the terminal under the premise of not relying on metal shielding through systematic hardware circuit design, simultaneously simplifies the structure, reduces the cost, and completely avoids the short circuit and failure risk caused by the shell grounding, and has higher reliability, environmental adaptability and economy.

The invention discloses an FF-FB cooperative four-unit active filter based on dual-core multiplexing. The FF-FB cooperative four-unit active filter comprises a noise source part, a load LISN network part and an active filter part, the active filter part comprises a current sampling branch, a first operational amplifier module, a second operational amplifier module, a voltage sampling branch, a plurality of current compensation branches, a first complementary output stage circuit and a second complementary output stage circuit; the two ends of the noise source part are connected with the left side of the active filter part, and the load LISN network part is connected with the right side of the active filter part. Feed-forward current sampling-current compensation is completed by using the multiplexing operational amplifier, and compensation is completed at the source end and the load end of the current transformer through two branches, so that secondary structure multiplexing is realized, and the problem that the operational amplifiers are added in topology is solved.

The application discloses a filter circuit and an implementation method and a filter device thereof, and relates to the technical field of filtering. The filter circuit comprises a signal filtering unit, an active filter unit, a clamping unit, a voltage input end and a voltage output end; wherein the output voltage flows into the signal filtering unit through the voltage input end, and the signal filtering unit is used for filtering the high-frequency small signal interference of the input voltage; the active filter unit is used for filtering the ripple and transient surge of the input voltage, and forming a direct current output voltage; the clamping unit is used for clamping the direct current output voltage at a fixed value and outputting through the voltage output end; wherein the signal filtering unit, the active filter unit and the clamping unit are electrically connected in sequence and arranged between the voltage input end and the voltage output end. According to the filter circuit of the embodiment of the application, the signal filtering unit can filter the high-frequency small signal interference; the active filter unit can filter the ripple and transient surge; and the clamping unit can clamp the direct current output voltage at a fixed value.

The present application provides a real-time optimization method, system and device for inverter output voltage harmonics, the method comprising: obtaining control parameters of an inverter; controlling the inverter to work according to the control parameters and obtaining N waveforms corresponding to N periods; decomposing the N waveforms to determine a to-be-processed waveform harmonic; when the amplitude of the to-be-processed waveform harmonic exceeds a harmonic threshold, a first optimization mode is used for optimization processing; when the amplitude of the to-be-processed waveform harmonic does not exceed the harmonic threshold, a second optimization mode is used for optimization processing. A method combining two harmonic reduction technologies is used, when the harmonic amplitude is small, the active filter function of the auxiliary inverter is used to reduce the harmonic, and the SHEPWM complex calculation is not used, when the harmonic amplitude is large, the SHEPWM technology is used to eliminate the harmonic, and the flexibility of inverter control is improved.

The invention relates to the technical field of magnetic tape units, in particular to a magnetic tape driver, a magnetic tape unit and a storage system.The magnetic tape driver comprises a read head, an analog equalization circuit and a digital processing chip; the read head is coupled with the analog equalization circuit, the analog equalization circuit is coupled with the digital processing chip, and the analog equalization circuit comprises an active filter; wherein the read head is used for reading an original analog signal from a magnetic tape of a magnetic tape unit and outputting the original analog signal to the analog equalization circuit; the analog equalization circuit is used for performing data equalization on the original analog signal through an active filter to obtain a first analog signal and outputting the first analog signal to the digital processing chip; the frequency response curve of the first analog signal is closer to the frequency response curve of a target signal type than the frequency response curve of the original analog signal, and the target signal type comprises partial response signals; and the digital processing chip is used for converting the analog signal into a digital signal and processing the digital signal. According to the embodiment of the invention, the order of the digital filter in the magnetic tape unit can be reduced.

The utility model discloses a pool water level on-line intelligent monitoring device, which is characterized in that a dual power supply is respectively connected with a Lora Internet of Things wireless communication transmission module, a single chip microcomputer control external storage module, an LCD (Liquid Crystal Display) and an audible and visual alarm through an active filter, and the single chip microcomputer control external storage module is connected with a pressure type liquid level sensor through an RS485 (Recommended Standard 485) transmission module; the Lora Internet of Things wireless communication transmission module is connected with the single-chip microcomputer control external memory module, the LCD display and the audible and visual alarm. The audible and visual alarm is located at the top of the machine box, and the pressure type liquid level sensor is located outside the machine box. According to the utility model, the fire pool water level condition can be effectively monitored, an alarm signal is sent out according to a set high-low water level alarm threshold value, the signal is fed back to the east well water pump and the west well water pump, the combination of the Lora Internet of Things and the fire pool water level online intelligent monitoring is successfully proposed by applying professional knowledge and technology, the fire pool low water level alarm time is shortened, and the fire pool water level alarm efficiency is improved. The emergency disposal time is optimized, and the stability of a fire extinguishing system is improved.

The invention provides a harmonic compensation method for a distributed active filtering system, and relates to the technical field of power distribution networks, and the method comprises the steps: obtaining load data and distributed power data of a power distribution network, and building a power distribution network Norton equivalent model based on a Norton equivalent circuit; pCC harmonic voltage is detected, harmonic responsibility coefficients of all feeder lines are calculated in combination with a Norton equivalent model of the power distribution network, and a harmonic responsibility quantification result is obtained; obtaining harmonic compensation capacity based on the harmonic responsibility quantification result, and dynamically adjusting virtual impedance through droop control to generate basic compensation current; based on the basic compensation current, the compensation capacity of each frequency is adjusted through a frequency division distribution algorithm; a compensation task is autonomously distributed in proportion through multiple inverters according to the adjusted compensation capacity of each frequency; according to the invention, the harmonic source is accurately positioned to optimize the compensation resource allocation, and the stability of the system is significantly improved through the autonomous cooperation of multiple devices.

The application relates to the technical field of reactive power compensation of power systems, and discloses a system for harmonic suppression and dynamic compensation of an active filter based on IGBT multi-mode regulation, which comprises a control module, a high-frequency harmonic detection module, an IGBT gate drive compensation circuit and an IGBT junction temperature observer. The high-frequency harmonic detection module is electrically connected to the control module and is configured to detect power grid harmonic signals in real time at a sampling rate of 200 kHz and transmit the signals to the control module. The IGBT gate drive compensation circuit is electrically connected to the control module and a preset IGBT module, and the control module dynamically adjusts the dead time and switching frequency of the IGBT module through the IGBT gate drive compensation circuit. The IGBT junction temperature observer is electrically connected to the IGBT module and the control module and is configured to monitor the junction temperature of the IGBT module in real time. When the junction temperature exceeds 125 DEG C, the control module triggers a derating protection mechanism. Based on the detection signals of the high-frequency harmonic detection module, the control module generates a PWM compensation waveform through a model predictive control algorithm unit, so that the IGBT module performs harmonic compensation through the IGBT gate drive compensation circuit.

Disclosed are a low-noise, short-offset transient electromagnetic receiving conditioning circuit and a receiver. The conditioning circuit includes: a first power supply filtering circuit, a second power supply filtering circuit, an active filtering circuit, a power frequency noise suppression circuit, and a low-noise amplification circuit. The first and second power supply filtering circuits are used to filter the first and second power supplies, respectively, to reduce noise. The active filtering circuit is designed to filter out interference signals. The power frequency noise suppression circuit is used to eliminate power frequency noise. The low-noise amplification circuit includes an input-stage amplification circuit, an intermediate-stage amplification circuit, and an output-stage amplification circuit. The technical solution of this disclosure incorporates multiple filtering circuits to remove noise, thereby facilitating noise reduction.

The invention relates to an active tunable multiband filter circuit. A wireless circuit may include a first filter circuit configured to output a signal in a first frequency range; a second filter circuit configured to output a signal in a second frequency range different from the first frequency range; and a signal combiner having a first input coupled to the first filter circuit and having a second input coupled to the second filter circuit. The wireless circuitry may further include: a first switchable impedance matching circuit coupled between an antenna and the first filter circuit; and a second switchable impedance matching circuit, wherein the second switchable impedance matching circuit is coupled between the antenna and the second filter circuit. The first filter circuit and the second filter circuit may be active filters, such as low-pass to band-pass conversion filters capable of operating in different frequency bands.

The utility model relates to an active filtering device, and relates to the field of active filters. Comprising an active filtering compensator main body A, an active filtering compensator main body B and a single-door cabinet body, the active filtering compensator main body is installed in the single-door cabinet body, and two sets of supporting cross beams arranged at intervals are arranged in the single-door cabinet body. The front ends of the active filtering compensator main body A and the active filtering compensator main body B are respectively arranged on the upper side and the lower side of the supporting cross beam through the same connecting piece A, and the tail ends of the active filtering compensator main body A and the active filtering compensator main body B are respectively arranged on the upper side and the lower side of the supporting cross beam through the same connecting piece B. The utility model has the following beneficial effects: two groups of active filter compensator main bodies can share one supporting cross beam, the installation number of the supporting cross beams is reduced, the occupied space of the supporting cross beams is reduced, and the arrangement and installation of a plurality of active filter compensator main bodies are satisfied.

A stepping type two-path active filtering control cabinet system comprises sampling current transformers 2TAa, 2TAb and 2TAc arranged in a capacitance compensation cabinet and sampling current transformers 1TAa, 1TAb and 1TAc arranged in an active filtering cabinet, and further comprises a plurality of active filtering modules connected in sequence, one end of each active filtering module is connected with the sampling current transformers 2TAa, 2TAb and 2TAc, and the other end of each active filtering module is connected with the sampling current transformers 1TAa, 1TAb and 1TAc. The other ends of the sampling current transformers 1TAa, 1TAb and 1TAc are connected with the sampling current transformers 1TAa, 1TAb and 1TAc; the system further comprises a centralized monitoring screen JKQ, and the signal acquisition end of the centralized monitoring screen JKQ is connected with the active filtering module. According to the application, current sampling is carried out on two paths of loads existing in a line, so that the active filtering module collects sampling current information; the centralized monitoring screen is used for performing centralized monitoring on the plurality of active filtering modules in the cabinet, thereby realizing step-by-step improvement of the electric energy quality of the line, improving the power supply reliability and protecting the equipment.

This invention proposes a design method for a full-band compact hybrid EMI filter circuit based on current feedback. The method includes: constructing an electromagnetic interference test circuit to obtain the common-mode EMI spectrum required for attenuation by the PWM converter, and establishing a high-frequency equivalent circuit for the PWM converter; obtaining the optimal hybrid EMI filter topology based on the high-frequency equivalent models of active and passive EMI filter circuits and the noise attenuation characteristics of the hybrid EMI filter circuit topology; designing the active EMI filter topology and its high-frequency equivalent model based on the noise cancellation principle of the active EMI filter and the common-mode EMI spectrum; designing the active EMI filter topology based on the noise cancellation principle of the active EMI filter and the common-mode EMI spectrum; designing the passive EMI filter structure based on the common-mode EMI noise spectrum after adding the active EMI filter; and designing the hybrid EMI filter circuit based on the hybrid EMI filter topology, the active EMI filter topology, the passive EMI filter structure, and the high-frequency equivalent models of the active and passive EMI filter circuits.

This invention provides an active filter with dustproof and noise reduction functions, belonging to the field of filter technology. It includes a supporting base shell, the top surface of which is vertically connected to a sealed top shell. The circulating cooling method can quickly and effectively dissipate heat from the device's interior, greatly improving heat dissipation efficiency. Compared with traditional natural heat dissipation or simple air cooling, it better meets the heat dissipation requirements of high-power-density active filters, ensuring that the device's temperature remains stable within a reasonable range during long-term high-load operation, effectively extending the device's service life. The guide tube design of the heat dissipation inner box is reasonable, guiding airflow evenly through all heat-generating areas inside the device, avoiding airflow dead zones and improving heat dissipation uniformity. Simultaneously, the installation of isolation and filter plates not only prevents dust from entering the heat dissipation inner box and the device's interior but also ensures smooth airflow, further improving the heat dissipation effect.

An analog filter circuit includes an active filter configured to filter a transmission signal, the active filter including an active element to which a power supply voltage is applied, and a passive filter connected to an output terminal of the active filter, the passive filter including a passive element having a dynamically variable impedance.

The application provides a stable control method, system and equipment of a smart light environment system in a harmonic environment, the method comprising: collecting electrical signals in real time based on an electric energy quality monitoring unit deployed at a key power distribution node of the smart light environment system, and extracting harmonic characteristic parameters based on the electrical signals; constructing a harmonic-light environment system dynamic coupling model based on the harmonic characteristic parameters; performing stability evaluation using a frequency domain impedance analysis method based on the harmonic-light environment system dynamic coupling model and the harmonic characteristic parameters, and obtaining a stability evaluation result; performing multi-objective optimization solving using a hierarchical optimization strategy based on the stability evaluation result, the harmonic characteristic parameters and a multi-objective optimization algorithm, and obtaining an optimal control decision; sending the optimal control decision to actuators of each lighting loop in the smart light environment system, and performing control mode switching or sending a treatment instruction to an active filter in the smart light environment system according to the stability evaluation result.

1. The name of the design product: active filter (wall-mounted). 2. The use of the design product: equipment for improving power factor of power grid, realizing dynamic reactive compensation. 3. The design points of the design product: in shape. 4. The picture or photo that can best show the design points: perspective view 1.

The application discloses a quality factor enhanced active filter and electronic equipment, and relates to the technical field of integrated circuit band pass filters. The quality factor enhanced active filter comprises a subtraction circuit, a first second-order quality factor enhanced active filter circuit and a second second-order quality factor enhanced active filter circuit which are electrically connected with the subtraction circuit. The first second-order quality factor enhanced active filter circuit and the second second-order quality factor enhanced active filter circuit each comprise variable gain sub-circuits, inductance-capacitance parallel resonance sub-circuits and negative resistance feedback sub-circuits which are electrically connected with each other. The subtraction circuit is connected with the variable gain sub-circuit. The application has the technical effects of a large gain adjustment range, unchanged center frequency points during gain and Q value adjustment, tunable center frequency, good rectangular coefficient and high linearity, and can be integrated and used in radio frequency front-end equipment.

The invention discloses a distributed active filtering system improved by adopting a filtering algorithm, which relates to the technical field of edge computing, and comprises the following steps: acquiring harmonic impedance information of an access point to cooperatively generate a real-time harmonic impedance distribution diagram reflecting the harmonic voltage sensitivity of the whole network; constructing a local revenue function of each node according to the harmonic impedance distribution diagram and the local state information; on the basis of the revenue function, limited information interaction and iterative gaming are carried out between adjacent nodes; and executing an optimal compensation strategy determined by the game, and performing feedback correction on the harmonic impedance distribution diagram. According to the method, the real-time harmonic impedance distribution diagram is generated cooperatively, so that each node has global perception capability; a comprehensive optimal decision is realized by constructing a multi-target revenue function fusing a local effect, a capacity utilization rate and a system contribution degree; and online correction is carried out on the model through actual effect feedback, the adaptability of long-term operation is ensured, and the contradiction between local optimization and a global target is fundamentally solved.