12 results about "Isolation amplifier" patented technology

The invention discloses a loop resistance measuring method, system and device, and relates to the technical field of electrical measurement. The method comprises the following steps of: performing loop data acquisition at each interface of the disconnecting switch adopting a three-channel wiring mode, injecting excitation current by an excitation source, and acquiring three-channel voltage original signals and initial sampling flow by a differential isolation amplifier to obtain the initial sampling flow; time sequence identification is carried out on the initial sampling flow to complete sample starting and ending point identification, inter-channel time alignment is completed, and a synchronous voltage sample set is output. According to the invention, by constructing a complete data chain covering high-precision synchronous sampling, adaptive signal processing, phase compensation calculation and intelligent statistical diagnosis, the problems of low measurement precision and insufficient anomaly identification capability caused by poor synchronism, phase error and lack of deep analysis in a traditional method are solved; the accuracy and anti-interference performance of loop resistance measurement and the intelligent level of state diagnosis are improved.

The invention relates to the technical field of high-voltage direct-current power transmission, and discloses a high-voltage direct-current converter valve cooling system flow sensor anti-interference circuit design method, which comprises the following steps: constructing a three-stage collaborative anti-interference system: a front-stage signal acquisition and primary protection circuit, a common-mode choke, a TVS diode and a PPTC resettable fuse combined network, and a high-voltage direct-current converter valve cooling system flow sensor anti-interference circuit; common-mode rejection and transient overvoltage protection are carried out on the original differential signals; the intermediate signal conditioning and isolating circuit is used for realizing accurate amplification of signals, thorough cut-off of ground loop interference and deep filtering through an instrument amplifier with a high common mode rejection ratio, an isolating amplifier and a second-order active Butterworth low-pass filter in sequence; the post-stage power supply anti-interference circuit provides a clean and stable power supply for the system through the cascade design of a pi-type filter, an isolation DC-DC, a magnetic bead isolation network and an ultra-low noise linear voltage regulator. According to the invention, through the full-link and multi-layer collaborative design, the anti-interference capability, the measurement precision and the operation reliability of the sensor in an extreme electromagnetic environment are improved.

Isolated circuit systems are provided. The systems include a primary side circuit and a secondary circuit, electrically isolated from each other. The primary side and secondary side circuits each utilize a direct current (DC) reference signal. The primary side circuit may use the DC reference signal in a modulation operation. The secondary side circuit may use the DC reference signal in a demodulation operation. The DC reference signal may be sent from the primary side circuit to the secondary side circuit, or from the secondary side circuit to the primary side circuit.

The present application discloses an isolation amplifier circuit. The isolation amplifier circuit comprises a modulation circuit, an isolation circuit, and a demodulation circuit. The modulation circuit receives an input signal and a first clock signal, and generates a first modulation signal and a second modulation signal according to the first clock signal and the input signal. The isolation circuit receives a second clock signal, the first modulation signal, and the second modulation signal, generates a first clock signal according to the second clock signal, generates a first demodulation signal according to the first modulation signal, and generates a second demodulation signal according to the second modulation signal. The demodulation circuit receives the first demodulation signal, the second demodulation signal, and the second clock signal, and generates an output signal according to the second clock signal, the first demodulation signal, and the second demodulation signal. In the present application, quantization noise generated by a first modulation circuit is canceled by performing, in a demodulation circuit, weighted summation of a second demodulation signal, generated according to the second modulation signal, with the demodulated first modulation signal, thereby achieving low noise in an isolation amplifier circuit.

The utility model discloses an isolation amplifier, and belongs to the technical field of amplifiers. The isolation amplifier comprises a four-path amplifier, a single-path amplifier, a first resistor, a feedback resistor, a first photoelectric coupling element and a second photoelectric coupling element, an inverted input end of the four-way amplifier is connected with a bias regulator at a high-voltage side and is connected with a signal input end through a first resistor, an in-phase input end of the four-way amplifier is connected to an inverted input end of the four-way amplifier through a photosensitive element of a second photoelectric coupling element, and an output end of the four-way amplifier is connected with a light-emitting element of the second photoelectric coupling element; the inverting input end of the single-path amplifier is connected with a bias regulator at a low-voltage side, and the non-inverting input end of the single-path amplifier is connected to the inverting input end of the single-path amplifier through a photosensitive element of the first photoelectric coupling element; the inverted input end of the single-path amplifier is connected to the output end of the single-path amplifier through a feedback resistor. According to the utility model, the problems of non-linear distortion, limited common-mode rejection capability and the like generally existing in multiple channels of the traditional isolation amplifier in the prior art are effectively solved.

This invention provides a DC voltage acquisition device for armored vehicles, comprising a sealed cavity formed between a sealing cover and a groove, a circuit board fixedly disposed within the sealed cavity, and two aviation connectors fixedly mounted on the side wall of the groove. The circuit board is equipped with a voltage divider circuit, an isolation amplifier circuit, and an operational amplifier circuit. One aviation connector is electrically connected to the input terminal of the voltage divider circuit; the output terminal of the voltage divider circuit is connected to the input terminal of the isolation amplifier circuit, and the output terminal of the isolation amplifier circuit is connected to the operational amplifier circuit; the output terminal of the operational amplifier circuit is electrically connected to its input terminal, and the output terminal of the operational amplifier circuit is electrically connected to the other aviation connector. The two aviation connectors and the circuit board are integrated together through the groove and the sealing cover to form a miniature voltage signal acquisition module, facilitating operation in relatively confined spaces while avoiding direct voltage signal acquisition through instruments, effectively protecting the instruments.

The utility model relates to a disconnection monitoring circuit for a current transformer. The disconnection monitoring circuit comprises a sampling module, a digital isolation amplifier, an operational amplifier module, a temperature sensor and an optocoupler module, the input end of the sampling module is connected with the current transformer, the output end is connected with the digital isolation amplifier, the input end of the operational amplifier module is connected with the digital isolation amplifier, and the output end is connected with the single-chip microcomputer. The temperature sensor is arranged on the sampling module, the input end of the optocoupler module is connected with the temperature sensor, and the output end of the optocoupler module is connected with the single-chip microcomputer. Compared with the prior art, the device has the advantages of safety, stability, high detection precision and the like.

The utility model relates to a TCR track circuit signal acquisition module, which comprises a power supply unit, an MCU unit, a PHY unit, a base plate unit and a PORT unit, the PORT unit comprises a DB9-M connector, the output end of the DB9-M connector is connected with an input isolation and impedance conversion circuit, the isolation and impedance conversion circuit is connected with an emitter follower circuit, and the emitter follower circuit is connected with a power supply unit. The emitter follower circuit is connected with an isolation amplifier, the output end of the isolation amplifier is connected with an AD module, and the AD module communicates with the MCU unit through an SPI serial port; a communication module is arranged between the MCU unit and the bottom plate unit, and the communication module comprises a CAN bus module and a 485 bus module; the base plate unit is connected with the power unit. According to the utility model, the isolation and impedance conversion circuit is arranged to filter high-frequency common-mode interference, the emitter follower circuit is arranged to enhance signal driving capability, reduce load effect and reduce signal attenuation, the isolation amplifier realizes electrical isolation of input and output ends, and the AD module is combined to realize signal acquisition.

The invention discloses a fuel cell AC impedance detection circuit structure, and belongs to the technical field of electrochemical AC impedance detection. The circuit structure comprises a blocking capacitor, a high-pass filtering and noise filtering module, a protection circuit, an isolation amplifier and an instrument amplification circuit which are electrically connected in sequence, the blocking capacitor is used for extracting AC voltage signals of the fuel cell, the high-pass filtering and noise filtering module is composed of a current-limiting resistor, a first resistor and a noise filtering capacitor and realizes low-frequency filtering and noise suppression, the protection circuit is used for suppressing high-voltage overshoot and undershoot during power-on and power-off, and the isolation amplifier realizes high-low voltage isolation transmission. The instrument amplification circuit improves the signal measurement precision. The problems that in the prior art, an isolation amplifier is prone to being damaged due to overshoot / undershoot, and signal precision loss is large are solved, and the method has the advantages of being remarkable in overshoot suppression effect, high in measurement precision and high in adaptability and can be widely applied to hydrothermal management optimization, electric pile service life prediction, fault diagnosis and other scenes of a fuel cell system.

A power supply control device of an electromechanical servo mechanism adopts a Darlington tube optocoupler and relay interlocking circuit, realizes multi-path power supply cooperative control and remote management through a USB concentrator and an Ethernet interface, and realizes high-precision isolation acquisition of voltage / current signals by utilizing an optocoupler isolation amplifier and a high-precision ADC (+ / -0.5% precision). And the STM32F407 single-chip microcomputer is used for realizing electromechanical servo'two-electricity 'automatic control, replacing manual operation, supporting local control / remote control mode switching and networking matching, and being suitable for electromechanical servo single-machine test and digital production line construction.

To provide a protection control system having an excellent input converter, a merging unit, and a protection control device.SOLUTION: A protection and control system comprising: an input conversion board (40) that receives an electric quantity of a power system through at least one of a shunt resistor (10) and a voltage dividing resistor (11), and converts the electric quantity of the power system into an electric signal while being electrically isolated by an isolation amplifier (12,13); an averaging process (2012,2016) that calculates an average value of an output of the input conversion board (40); a subtraction process (2013,2017) that subtracts the average value from the output of the input conversion board (40); and a protection and control operation unit that performs at least one of protection and control of the power system using an output of the subtraction process (2013,2017).SELECTED DRAWING: Figure 3