32results about How to "Reduce common mode interference" patented technology

The invention discloses a non-bridge APFC active factor power correction circuit which comprises an AC positive half cycle APFC circuit, an AC negative half cycle APFC circuit, and an AC filter circuit, wherein the AC positive half cycle APFC circuit comprises a first inductor, a first switch tube, a positive half cycle first diode, a positive half cycle second diode, a first capacitor, a first PFC controller and a first DC-DC converter as a load, and the AC negative half cycle APFC circuit comprises a second inductor, a second switch tube, a negative half cycle first diode, a negative half cycle second diode, a second inductor, a second PFC controller and a second DC-DC converter as a load. Compared with conventional non-bridge APFC circuit, the non-bridge APFC active factor power correction circuit has lower loss, and smaller electromagnetic interference.

The embodiment of the invention discloses a method and device for processing information and electronic equipment. The method and device are applied to the electronic equipment with a capacitive touch display unit. When it is detected that the electronic equipment is connected with an external charging device, whether currents of the external charging device have interference signals is monitored, and whether misinformation points exist in the capacitive touch display unit is monitored; when it is detected that interference signals exist in the currents of the external charging device, and the misinformation points exist in the capacitive touch display unit, the charging mode of the charging device is controlled and adjusted, the current first charging mode of the electronic equipment is switched to the second charging mode, charging currents in the second charging mode are smaller than that of the first charging mode, and therefore common mode interference due to the fact that the electronic equipment with the capacitive touch display unit is connected with an external power supply is lowered.

Disclosed is a sending device for transmitting video signals with an ultrahigh resolution ratio and an ultrahigh frame rate through dual twisted pairs. The sending device comprises a chroma space conversion unit, a YUV gain control unit, an image division unit, a coding unit and a D/A conversion unit which are sequentially connected are included; as for the video signals, the RGB format is converted into the YUV format through the chroma space conversion unit, and the brightness and chroma are adjusted through the YUV gain control unit; the image division unit is used for dividing the adjusted video signals into a plurality of sub images; the coding unit is used for coding the brightness Y and the chroma UV separately; and the sub images are converted into analog signals through the D/A conversion unit so that the analog signals can be transmitted on a dual-twisted-pair transmission line. The sending device has the advantages of low structuring cost and simple mode, and is beneficial for restraining common mode interference and reducing attenuation. By means of the sending device, multi-path frequency decrease treatment is achieved, the requirement for bandwidth of each signal transmission line is lowered, the degree of distortion of transmission frequency is lowered, and meanwhile, transmission problems caused by mutual interference of brightness and chroma is effectively solved.

The invention discloses a five-mass-block biaxial detection silicon micro resonant gyroscope based on out-of-plane vibration. The gyroscope comprises a first mass block, a polar plate substrate, a transmission beam, two mass blocks which are located at symmetrical positions and sensitive to Y-axis angular velocity, two mass blocks which are located at symmetrical positions and sensitive to X-axis angular velocity, detection comb teeth, anchor points, lever supporting beams and a frame. The first mass block and the polar plate substrate form a capacitor structure, so that the first mass block generates simple harmonic vibration in the Z-axis direction, and the simple harmonic vibration is transmitted to the other four mass blocks through the supporting beams between the first mass block and the other four mass blocks. The the other four mass blocks are enabled to achieve simple harmonic motion in the Z-axis direction the same as that of the first mass block, when angular velocity in the X-axis direction or the Y-axis direction occurs, Coriolis force is generated on the four mass blocks, and angular velocity detection in the X-axis direction and the Y-axis direction is achieved through the comb tooth detection structure. According to the invention, real-time, high-precision and high-sensitivity measurement of the out-of-plane vibration five-mass-block double-axis angular velocity is realized.

The invention discloses a fetal electrocardiogram orthorhombic lead system, which comprises a chest lead electrode V1, three abdomen lead electrodes P1, P2 and P3, a public common terminal electrode COM and a grounding electrode GND, wherein the abdomen lead electrodes P1, P2 and P3 are arranged at an uterine orifice; the common public terminal electrode COM is arranged at the bottom of a uterus; and the grounding electrode GND is arranged a lowermost rib below a right armpit middle line. Due to the adoption of the orthorhombic lead system, clean fetal electrocardiosignals are obtained; and an orthorhombic lead plane is utilized, so that interference is reduced greatly, and the detectable rate of fetal electrocardiograms is increased.

The invention belongs to the technical field of electric control, particularly relates to a control method suitable for a non-isolated single-phase photovoltaic grid inverter circuit, and aims at providing the control method suitable for the non-isolated single-phase photovoltaic grid inverter circuit, so as to improve the efficiency of a topological inverter with six switch tubes and reduce common-mode interference caused by on/off of the switch tubes in the circuit. In order to achieve the purposes, the technical scheme provided by the invention is that the control method suitable for the non-isolated single-phase photovoltaic grid inverter circuit comprises the steps of distinguishing control sequences of a first switch tube S1 and a sixth switch tube S6, and distinguishing the control sequences of a third switch tube S3 and a fourth switch tube S4. According to the control method, the realization is simple and convenient, the topological structure does not need to be changed, switch losses of the switch tubes are reduced, and the common-mode interference is reduced, so that the efficiency of the inverters is improved.

The invention provides a switching-on control method for an alternating-current switch of a grid-connected inverter. The switching-on control method comprises the following steps: real-time sampling is performed on power grid voltage and inversion current; coordinate transformation is carried out on the power grid voltage and the inverter current to obtain a voltage component and a current component; the current component is processed through a virtual impedance loop to obtain a corresponding output current component; the voltage component of the power grid voltage and the output current component are superposed to obtain a modulated wave component; coordinate transformation is carried out on the modulated wave component to obtain a multi-phase power grid voltage modulated wave, and pulsewidth modulation is carried out on the multi-phase power grid voltage modulated wave to generate inverter circuit drive; the voltage difference between the voltages at the two ends of the AC switch and the power grid voltage is determined to be within the preset range, the AC switch is controlled to be switched on, the problem that the AC switch has no impact current is solved, and the technical problem of large open-loop control inductive current is solved.

The invention relates to temperature measurement technologies and discloses a device for improving the temperature measurement accuracy in complex environment. The antijamming capability is improved, so that temperature data obtained by measurement have higher reliability. A core assembly composed of a twisted pair, an equal-arm bridge and a differential amplifier is adopted, common-mode interference in a signal pickup path is reduced, the equal-arm bridge unbalance amount, caused by temperature changes, of a thermistor is fed into the differential amplifier in a voltage mode, and finally the differential amplifier outputs signals to be provided for an analog-to-digital conversion circuit to carry out voltage sampling or other subsequent processing. The device is applicable to temperature measurement in the complex environment.

The invention discloses a signal quality stable output circuit of an infrared detector. The signal quality stable output circuit comprises a main processor FPGA, a temperature acquisition circuit, a detector bias control circuit and a detector signal acquisition circuit; the temperature acquisition circuit acquires the working environment temperature of the infrared detector, digitalizes the temperature and sends the digitalized temperature to the main processor FPGA; the main processor FPGA updates a detector bias voltage working instruction according to the temperature acquired by the temperature acquisition circuit and sends the detector bias voltage working instruction to the detector bias voltage control circuit; the detector bias control circuit updates the working voltage VR and Vgpol of the infrared detector according to a detector bias working instruction. The detector signal acquisition circuit corrects an output analog image signal according to the working voltage VR and Vgpol of the infrared detector, digitizes the analog image signal and sends the digitized analog image signal to the main processor FPGA. Acquisition of the environment temperature is completed through the temperature acquisition circuit, the acquired temperature is used as guidance, prior information is read, the detector bias voltage is configured through the detector bias voltage control circuit,bias voltage real-time configuration is achieved, and image signal output is stabilized.

The present invention provides a lead-on detection circuitry of a biopotential acquisition system. The lead-on detection circuitry includes an input terminal, a duty-cycle controller, a transmitting signal generator and a mixer-based receiver. The duty-cycle controller is configured to generate a first clock signal. The transmitting signal generator is configured to generate a transmitting signal to the input terminal according to the first clock signal. The mixer-based receiver is configured to perform a mixing operation based on the first clock signal and the transmitting signal to generate an output signal, wherein the output signal indicates if an electrode of the biopotential acquisition system is in contact with a human body, and the electrode is coupled to the input terminal. According to the embodiment of the invention, power line common-mode interference and electrode tissue offset can be reduced, and the detection accuracy is improved.

The invention relates to a micro-mechanical sensor device for measuring acceleration, pressure and similar parameters. The device has a seismic mass movably arranged at a substrate. A converter unit e.g. resistors (WH, WS), converts forces by a piezoeffect unit to a piezoresistive and/or piezoelectric detection unit. The forces act on the seismic mass into an electric signal by a piezoeffect. A control unit controls a force application unit i.e. electrodes, such that the seismic mass is temporarily applied with supplementary force. The converter unit comprises suspensions i.e. beams, which movably define the seismic mass at the substrate. An independent claim is also included for a method for measuring acceleration and pressure for a micro-mechanical sensor device.

The invention discloses a multilevel circuit and an isolated power circuit thereof, in order to reduce common mode interference. The isolated power circuit comprises a plurality of isolated power supplies, the power supplies are used for supplying power for isolated driving chips, wherein the isolated driving chips corresponding to switching tubes not common-ground in the multilevel circuit are powered by different isolated power supplies; secondary sides of the isolated power supplies are in common-ground with the switching tubes driven by the isolated driving chips respectively powered by the isolated power supplies; the plurality of isolated power supplies are respectively numbered as 1, 2, 3, ..., m-1 and m isolated power supplies, m refers to the total number of the plurality of isolated power supplies, then the primary side of the first isolated power supply is in common-ground with an auxiliary power supply, or a ground end of the primary side of the first isolated power supply is suspended; and the ground end of the secondary side of the first isolated power supply is connected with the midpoint of a DC bus; the primary side of the first isolated power supply is in common-ground with the secondary side of an arbitrary isolated power supply in the previous (i-1) isolated power supplies, wherein i = 1, 2, 3, ..., m-1 and m.

According to the invention, means for reducing the interference caused by a voltage or a current in common mode, comprise adders (S3; S4) in each path for adding a first counter-reaction voltage (VI) to the voltage of the relevant path, a bridge (R1, R2) and an inverter (I3) for provision of said first counter-reaction voltage which is equal to half the sum of the voltages (VA; VB), respectively supplied to the inputs (A; B), with an opposing sign. According to the invention, the effect of a delay introduced by the inverter (I3) may be reduced, whereby said stage further comprises means (S5; S6) for adding in addition to the input voltage for each path, a second counter-reaction voltage (Val; Vbl), and means (R1, R2,; I1, S1; I2, S2) for provision of a second counter-reaction voltage (Val; Vbl) which is a function of the input voltage (VA; VB) at the input corresponding to said path, with an opposing sign and with a delay identical to that generated by the inverter (I3).

The invention discloses a circuit, a system, a method and a controller for suppressing common-mode interference, and relates to the technical field of power electronics. The circuit comprises a sampling circuit which is configured to collect a common-mode interference signal of a parasitic capacitor between a casing and a grounding end of a controller; the controller is configured to output a control signal to the injection circuit according to the common-mode interference signal acquired by the sampling circuit; and an injection circuit configured to inject an adjustment signal to the chassis according to the control signal output by the controller to suppress the common-mode interference signal. Through mutual cooperation of the sampling circuit, the controller and the injection circuit, the adjusting signal is injected into the casing, common-mode interference can be reduced, and the electromagnetic performance of equipment is improved.

The invention provides a switching power supply circuit and electronic equipment. The switching power supply circuit comprises a rectifying circuit, an energy storage circuit, a switching tube and a transformer; the rectifying circuit, the energy storage circuit, the transformer and the switching tube are arranged on the substrate, and the substrate is provided with the ground; and the cathode output end of the rectifying circuit and a connecting line form a power ground of the switching power supply circuit, and the power ground is electrically connected with the ground through a wire. According to the scheme provided by the invention, the grounding loop is arranged between the power ground of the switching power supply circuit and the ground, so that common-mode noise conducted to the ground through the ground distributed capacitance of the switching tube and common-mode noise conducted to the ground through the ground distributed capacitance of the secondary side of the transformer can flow back to the switching tube through the grounding loop, the influence of noise on a post-stage load or a power supply is avoided, and the interference of the switching power supply circuit is reduced.