185 results about "Negative resistance" patented technology

The invention discloses an impedance characteristic remodeling method, device and equipment and a medium, and is applied to the field of wind turbine generators. Wherein the corresponding rotor reference current is determined according to the electromagnetic reactive power, the active power and the corresponding power reference value; correcting the rotor current according to the rotor reference current by adopting a virtual admittance control mode, and generating a corresponding rotor voltage given value; sequentially performing differentiation, filtering and signal extraction processing on the rotor reference current and the rotor current to obtain an impedance remodeling signal; and correcting the rotor voltage given value based on the impedance remodeling signal so as to enable the corrected rotor voltage given value to serve as the control voltage of a rotor side converter in the medium-voltage doubly-fed wind turbine generator after impedance characteristic remodeling. The virtual admittance control mode and the impedance remolding signal mode are adopted to suppress the negative resistance effect of the rotor side converter in the medium-voltage doubly-fed wind turbine generator under voltage disturbance, and therefore the damping effect on external excitation in the sub-super-synchronous frequency band and the high frequency band is higher.

A low-phase noise class-D voltage-controlled oscillator based on a broadband harmonic shaping technology comprises a head resonance unit, an LC resonance unit composed of a first inductance unit, a second inductance unit and a first capacitance unit, a negative resistance unit, a variable capacitance unit, an array capacitance unit and an output unit. The output end of the head resonance unit is connected with one end of the first inductance unit, the other end of the first inductance unit is connected with one end of the negative resistance unit, the other end of the negative resistance unit is connected with the first capacitor unit, the first capacitor unit is connected with the variable capacitor unit, and the variable capacitor unit is connected with one end of the array capacitor unit. The other end of the array capacitor unit is connected with one end of the second inductor unit, the other end of the second inductor unit is grounded, two input ends of the output unit are connected with the variable capacitor unit, and two output ends of the output unit serve as output ports of the voltage-controlled oscillator.

An example system for passive sensing includes a coupled pair of resonators including a sensor resonator and a reader resonator, the sensor resonator including a resistor a loss associated with the resistor, and the reader resonator including a MOS cross-coupled pair that implements a nonlinear gain of the reader resonator via compressive saturation of negative resistance. An amplitude detector measures the amplitude of oscillations associated with the reader resonator, and the negative resistance is determined based on the measured amplitude of oscillations associated with the reader resonator when the measured amplitude reaches a steady state, i.e., when the gain of the reader resonator balances the loss of the sensor resonator. The resistance associated with the resistor of the sensor resonator may be determined based on the determined negative resistance. When the resistor is a resistive sensor, indications of measurements by the resistive sensor may be determined in this way.

The invention provides a continuous time Sigma-Delta modulator with constant transconductance bias and negative resistance compensation. The continuous time Sigma-Delta modulator comprises a loop filter, a quantizer and a digital-to-analog converter, the loop filter is used for amplifying a signal in an effective signal bandwidth and attenuating an out-of-band signal at the same time, and the loop filter comprises a first-stage negative resistance compensation integrator and a second-stage negative resistance compensation integrator which are connected in sequence, the first-stage negative resistance compensation integrator comprises a first negative resistance unit containing a negative resistance of a constant transconductance bias circuit and a first integrator unit containing an operational amplifier, and a single operational amplifier resonator structure is formed to generate a second-order response; the integrator of the second-stage negative resistance compensation comprises a second negative resistance unit and a second integrator unit comprising an operational amplifier; and the quantizer is connected with the loop filter, adopts a successive approximation analog-to-digital converter, and is used for converting the analog voltage signal into a digital signal and outputting the digital signal. And the digital-to-analog converter is used for converting the digital signal into an analog signal and feeding back the analog signal to the loop filter.

The invention discloses an APT symmetric sensing system and method based on singular point degeneracy. The APT symmetric sensing system comprises a reader and two sensors. The reader comprises an inductor, a capacitor and a negative resistor; each sensor comprises an inductor, a capacitor and a loss resistor; and respectively applying disturbance to the two sensors according to the detected parameters, and detecting the working frequency of the wireless sensing system to obtain the corresponding detected parameters. Through degeneracy of different types of singular points, system frequency splitting is in direct proportion to a quarter of perturbation, so that the detection sensitivity of the system is greatly improved, the sensor can detect obvious changes under tiny disturbance, and especially in an application scene needing to accurately detect tiny changes, the detection sensitivity is greatly improved. Meanwhile, the singular junction with the high sensitivity characteristic is obtained only in a third-order system through regulation and control over the singular points, and compared with an existing fourth-order system for achieving the singular junction, the number of resonators is reduced.

The invention provides a damping boosting method for a high-inertia energy storage type synchronous phase modifier based on stator voltage feed-forward compensation, which is used for respectively calculating d-axis compensation modulation voltage and q-axis compensation modulation voltage of a grid-side converter and a rotor-side converter, and is used for enhancing small-disturbance stability in an HIESSC wide-slip operation range. Under a weak power grid connection condition, the method feeds HIESSC stator voltage disturbance forward to a rotor side converter and a grid side converter controller output voltage through a transfer function, so that reduction of a negative resistance region of HIESSC impedance characteristics can be realized, and adverse effects of grid-connected point voltage disturbance are inhibited, thereby improving the HIESSC impedance characteristics and enhancing small disturbance stability of an HIESSC grid-connected system.

The embodiment of the invention provides a voltage-controlled oscillator, an oscillator circuit, a chip and electronic equipment, relates to the technical field of communication or radar detection, and can improve the linearity of the voltage-controlled oscillator. The voltage-controlled oscillator comprises a voltage-controlled oscillator resonant cavity, an even harmonic generator circuit and a self-mixing frequency tripler circuit. The voltage-controlled oscillator resonant cavity comprises a voltage transformation diode array and a first-stage mode switching capacitor. The even harmonic generator circuit comprises a group of cross coupling tubes, one end of each cross coupling tube is electrically connected to the two differential ends of the voltage-controlled oscillator, and the even harmonic generator circuit serves as an even harmonic generator and is electrically connected to the self-mixing frequency tripler circuit. The self-mixing frequency tripler circuit comprises a differential unit and a resonant cavity, and one end of the self-mixing frequency tripler circuit is electrically connected to the even harmonic generator circuit. The low-frequency voltage-controlled oscillator and the self-mixing frequency tripler circuit achieve current multiplexing, the even harmonic generator circuit serves as a negative resistor of the oscillator and also serves as an even harmonic generator of the self-mixing frequency tripler, and the linearity of the millimeter wave frequency source is improved.

[Problem] To provide: a semiconductor electricity storage material formed from a bio-material and having semiconductor properties and electricity storage properties; an electricity storage body; and a layered electricity storage body. [Solution] The present invention has fibers containing chitin or chitosan as the primary component, is in the form of a sheet, and has a density of 2 g / cm3 or less. Preferably the fibers are crystallized or amorphous fibers. Preferably the fibers are chitosan nanofibers having a width of 3 to 400 nm, or are formed from bundles or particle-like aggregates of chitosan fibers. Preferably the semiconductor is an n-type bulk semiconductor and preferably has N-type negative resistance.

The invention relates to a CMOS voltage-controlled oscillator applied to an anti-interference unmanned aerial vehicle millimeter wave radar, which belongs to the field of millimeter wave radar design and comprises a resonance circuit, a negative resistance active circuit and two switching circuits with the same structure. The resonant circuit comprises a switched capacitor, a blocking capacitor, a resonant capacitor, a grounding resistor, a tuning resistor and a resonant inductor; the negative resistance active circuit comprises a cross coupling pair MOS tube and a current source. Each switch circuit comprises a switch MOS tube, a grounding resistor and a switch coupling inductor. The dual-phase transformer structure is used, the resonant inductor and the switch coupling inductor are mutually inducted, and therefore the inductance value of the resonant inductor is changed, and frequency band switching is achieved; vCO bandwidth tuning is realized through a combination mode of switch-on and switch-off of a switch capacitor and switch-on and switch-off of a switch coupling inductor; the CMOS technology is adopted for design, and miniaturization and integration of the VCO are achieved. While the performance and layout area of the voltage-controlled oscillator are ensured, the full-band broadband tuning range is realized, thereby improving the detectability and resolution of the millimeter wave radar, enabling the unmanned aerial vehicle to realize frequency hopping communication and spread spectrum communication, and effectively improving the anti-interference capability and safety of the unmanned aerial vehicle.

The invention discloses a voltage-controlled oscillator with a wide frequency regulation range, relates to the technical field of radio frequency, and aims to solve the problems of narrow and discontinuous output frequency tuning range of an oscillator in the prior art. The voltage-controlled oscillator comprises a passive topology module, an active negative resistance module, a frequency regulation module and a mode switching module, the passive topology module comprises a plurality of mutually coupled inductors; the plurality of inductors are coupled together and provide a required impedance peak; the plurality of inductors comprise a splayed inductance coil, a first annular inductance coil and a second annular inductance coil; the inverted V-shaped inductance coil comprises a first inductance coil, a second inductance coil and a public inductance coil; the frequency adjusting module is used for adjusting the corresponding frequency of the impedance peak; the active negative resistance module is used for providing signal gain for the passive topology module to meet oscillation conditions, and the mode switching module is used for switching working modes of the oscillator. The oscillator has four continuous working frequency bands, and the tuning range of the output frequency is wider.

The invention discloses a low-power-consumption voltage-controlled oscillator based on an SOI (Silicon On Insulator) process, relates to the technical field of integrated circuit design, and is used for solving the technical problem that an existing Colpitts oscillator is too high in power consumption and cannot be applied to a low-power-consumption integrated circuit. The invention discloses a low-power-consumption voltage-controlled oscillator based on an SOI (Silicon On Insulator) process. The low-power-consumption voltage-controlled oscillator comprises a Colpitts resonance circuit, a negative resistance unit and an LC filter network, the negative resistance unit is at least provided with a pair of RC network bias NMOS transistors and a pair of cross-coupled NMOS transistors, and the drain electrodes of the RC network bias NMOS transistors are connected with the Colpitts resonance circuit; the input end of the LC filter network is connected with the source electrodes of the cross-coupled NMOS transistors; the negative resistance unit biases the NMOS transistor through the RC network to introduce a feedback path to form a C-class oscillator structure, the Colpitts resonance circuit generates a first signal, and the first signal passes through the negative resistance unit and is output after common-mode noise is filtered by the LC filter network.

The invention discloses a voltage-controlled oscillator with small-area and wide-band modulation capability, and particularly relates to the technical field of radio frequency integrated circuits. The voltage-controlled oscillator comprises two symmetrical voltage-controlled oscillation units; wherein each voltage-controlled oscillation unit comprises a resonance circuit; the resonance circuit comprises an LC resonance circuit and a negative resistance active circuit; the LC resonant circuit comprises a switched capacitor array; two ports of the LC resonance circuit are respectively connected to the output ends of the cross coupling MOS pair; the switched capacitor array is used for providing at least two gears of variable capacitance; the negative resistance active circuit comprises a cross coupling pair transistor and a bias current source; the mode change-over switch circuit comprises two groups of symmetrical switch MOS (Metal Oxide Semiconductor) tubes and mutual inductance transformer taps; and in each voltage-controlled oscillation unit, a tap of the resonant inductor is connected with a corresponding port of the mode switching switch MOS tube. According to the scheme, the mismatch effect caused by a small process and the stray capacitance caused by layout and wiring can be reduced as much as possible, and the chip area can be reduced while the performance is ensured, so that the tape-out cost is reduced.

The invention discloses an impedance modeling and grid-connected stability analysis method based on a flexible excitation synchronous machine, and the method comprises the steps: dividing the flexible excitation synchronous machine according to a topological structure and a control block diagram of the flexible excitation synchronous machine; according to topological structure division of the flexible excitation synchronous machine, modeling is carried out on the synchronous machine, an excitation system machine side and an excitation system network side; a unified impedance model considering a phase-locked loop, a current loop, a DC voltage loop, a reactive power loop, an excitation voltage loop and a dual-channel proportional link is established, and the accuracy of the impedance model is verified through simulation frequency sweep. And converting the 2 * 2 admittance matrix into an equivalent SISO model to analyze the stability of the system so as to position the negative resistance frequency band existing in the system. And finally, verifying the accuracy of grid-connected stability analysis through the simulation model. Therefore, the method is more suitable for simpler working conditions and has very high applicability.

The invention discloses a passive gasket type pressure sensor based on parametric negative resistance self-excitation and a monitoring method, and belongs to the technical field of bolt loosening state monitoring. The sensor is improved based on a standard metal flat washer, a piezoelectric sensing unit, a pilot frequency response passive network and a passive heat-induced drift suppression circuit are embedded, and an embedding area is filled with organic silica gel. The pilot frequency response passive network uses parametric reactance to modulate nuclear strength nonlinearity to generate active negative resistance, weak radio frequency energy self-excitation is achieved, and bolt axial load change is mapped into echo frequency sideband drift; the thermally induced drift suppression circuit eliminates temperature drift. According to monitoring, the environment temperature is determined through temperature echoes, a frequency-load curve is matched, and then the bolt loosening state is determined through bolt loosening state echoes. Passive, wireless, maintenance-free and high-precision monitoring is realized, and the problems of high starting threshold, near communication, poor integration and the like in the prior art are solved.

The invention discloses a four-core F23 type millimeter wave voltage-controlled oscillator based on an intra-core common mode technology. The voltage-controlled oscillator comprises a three-coil coupling four-core class-F inductor and four voltage-controlled oscillator cores. The three-coil coupling quad-core class-F inductor comprises eight differential ports, four ports are connected with a grid electrode of a core negative resistance tube of the voltage-controlled oscillator, and the other four ports are connected with a drain electrode of the core negative resistance tube of the voltage-controlled oscillator. The negative resistance tubes of the four voltage-controlled oscillator cores are formed by NMOS tubes and PMOS tubes in an alternating mode. The voltage-controlled oscillator is in an F-type working state for differential mode current so as to improve phase noise; noise filtering is performed on the common-mode current through an intra-core natural common-mode path. According to the invention, millimeter wave frequency output with low phase noise can be realized in a compact layout.

The invention provides a Class C inductance-capacitance voltage-controlled oscillator with a wide tuning range, which belongs to the technical field of voltage-controlled oscillators and is composed of an LC resonance circuit and a negative resistance area circuit which are connected in parallel. The LC resonant circuit comprises an on-chip symmetrical spiral inductor, a switched capacitor array, a first variable capacitance tube CV1 and a second variable capacitance tube CV2; the negative resistance area circuit comprises a tail current tube M, a first filter capacitor C1, a second filter capacitor C2, a first cross coupling triode Q0, a second cross coupling triode Q1, a first resistor R0, a second resistor R1, a first filter inductor L3 and a second filter inductor L4; the negative resistance area circuit is connected with the LC resonance circuit; through the switched capacitor array and the two variable capacitance tubes which are matched with each other, the wide tuning range frequency output is realized, and through improving the structure of the switched capacitor array, the anti-interference performance is enhanced, and the phase noise is optimized at the same time.

The invention discloses an on-chip active reconfigurable filter passband flatness optimization method and circuit, and belongs to the field of integrated circuits and wireless communication. The filter comprises a coupling element, negative resistance compensation units are connected to the two ends of the coupling element and connected with the coupling element in parallel, and the coupling element comprises a coupling inductor or a coupling capacitor. The invention provides a passband flatness method based on active coupling compensation by deeply analyzing the passband flatness distortion reason of the on-chip coupling filter, and designs a detailed controllable negative resistance unit to compensate the coupling (inductive coupling) loss of the base transformer, thereby greatly reducing the in-band insertion loss variation of the filter, and improving the filter performance. And the amplitude consistency of the signal after passing through the filter is improved.

The invention relates to an optimal proportioning method for a grid-constructing type wind turbine generator and a grid-following type wind turbine generator in a wind power plant, solves the problem of subsynchronous oscillation of the grid-following type wind turbine generator in the wind power plant under a weak power grid, and belongs to the technical field of electrical equipment. The method comprises the following steps: respectively establishing state space models of single machines and power grid lines of a network-constructing type wind turbine generator and a network-following type wind turbine generator; according to the established state space model, single-machine port frequency domain impedance in the grid-forming type wind turbine generator set and the grid-following type wind turbine generator set is obtained, black box processing is conducted on all the generator sets, and the equivalent impedance of a whole grid-connected port of the wind power plant is calculated in combination with the connection mode between the wind turbine generator sets and the connection mode between the wind turbine generator sets and a power grid line; positive and negative resistance and capacitive-inductive reactance characteristics of the subsynchronous frequency band are obtained according to the equivalent impedance, the overall interference stability of the wind power plant is judged according to the characteristics, if the stability is not stable, the proportion of the net-forming type wind turbine generator is increased, the equivalent impedance is calculated again till the stability is achieved, and the proportion is output.

The invention discloses a series resonance voltage-controlled oscillator with a mode switching function, which comprises a series resonance mode switching switch and two series resonance oscillator units which are in coupled connection, and each series resonance oscillator unit comprises an active negative resistance network and an LC resonance network, the LC resonance network comprises a first inductor, a first capacitor and a second inductor which are sequentially connected in series, and the first inductor and the second inductor are connected with the two output ends of the active negative resistance network in a one-to-one correspondence mode. A first node is arranged on a line between the first inductor and the active negative resistance network, a second node is arranged on a line between the second inductor and the active negative resistance network, and the series resonance mode change-over switch is used for controlling switching of an even mode and an odd mode. When the series resonant oscillator is applied, the reliability of mode switching can be guaranteed, meanwhile, parasitic capacitance of the mode switching switch cannot be introduced into the series resonant cavity, the tuning range cannot be compressed, and the frequency tuning range of the series resonant oscillator can be widened.

The invention discloses an LC oscillator, which comprises a power supply, a complementary cross coupling negative resistance amplifier, an inductor, a switched capacitor array, a tuning variable capacitor and a power supply traction compensation circuit, and is characterized in that when the voltage of the power supply changes, the voltage of a first output node and the voltage of a second output node change along with the voltage of the power supply; and the variable capacitance in the power supply traction compensation circuit is adjusted, so that the parasitic capacitance of the complementary cross coupling negative resistance amplifier, the capacitance in the switched capacitor array and the capacitance change of the tuned variable capacitance are counteracted. The power source traction compensation circuit provides a positive power source traction compensation coefficient or a negative power source traction compensation coefficient, and the two ends of the power source traction compensation circuit are directly connected with the first output node and the second output node. The bias voltage changing along with the power supply voltage and the constant bias voltage irrelevant to the power supply do not need to be additionally provided, the circuit complexity is reduced, and therefore the power consumption and the area are reduced.

The invention relates to a near-earth orbit satellite internet millimeter wave oscillator based on a single-phase multi-winding transformer, which belongs to the field of near-earth orbit satellite communication design and comprises three resonance circuits with the same structure and a negative resistance active circuit. Each resonant circuit comprises a switch capacitor, a blocking capacitor, a resonant capacitor, a grounding resistor, a tuning resistor, a resonant inductor and a switch coupling inductor, and each negative resistance active circuit comprises a cross coupling pair MOS tube and a current source. The resonant inductor and all the switch coupling inductors are of a single-phase multi-winding transformer structure, only one voltage-controlled oscillation unit works under different working frequency bands, and tuning of the VCO bandwidth is achieved in a combined mode of switching on and switching off of the switch capacitors and switching on and switching off of the switch coupling inductors. Under the condition that the layout area and the design complexity of a chip are ensured, all frequency bands currently distributed by the working millimeter waves of the voltage-controlled oscillator are enabled to realize a wide frequency tuning range.

The invention discloses a voltage-controlled oscillator and a sub-sampling phase-locked loop, and relates to the technical field of phase-locked loops. The voltage-controlled oscillator comprises two negative resistance transistors and a three-layer coil structure; the three layers of coil structures are respectively a drain coil, a grid coil and a source coil from outside to inside; the gate coil and the drain coil are both of an octagonal structure, and the source coil is of a splayed structure; the drain coil, the source coil and the grid coil are all provided with center taps, the center tap of the source coil is connected with a power voltage module, the center tap of the drain coil is grounded, and the connection point of the center tap of the source coil and the power voltage module and the connection point of the center tap of the drain coil and the ground are located on the same side of the drain coil. And the two negative resistance transistors are positioned on the other side of the drain coil. According to the invention, automatic alignment of second harmonics in a wide frequency range is realized. And meanwhile, an extra chip area is not increased.

A frequency multiplier includes an oscillator and a harmonic generator. The oscillator has a resonant cavity and a negative resistance unit. The negative resistance unit includes a feedback capacitor and a parasitic capacitor. The feedback capacitor and the parasitic capacitor collectively provide negative resistance for the resonant cavity. The harmonic generator is configured to generate a harmonic signal based on a fundamental frequency signal taken as input. The oscillator is electrically connected to the harmonic generator, and is configured to receive the harmonic signal, and to output an intrinsic signal with the resonant cavity. A frequency of the intrinsic signal is a multiple of a frequency of the fundamental frequency signal.

The invention discloses an anti-radiation low-phase noise voltage-controlled oscillator based on an SOI (Silicon On Insulator) process, relates to the technical field of oscillators, and is used for solving the technical problem that the existing voltage-controlled oscillator based on the SOI process cannot realize low phase noise and high anti-radiation capability at the same time. The anti-radiation low-phase noise voltage-controlled oscillator based on the SOI technology comprises an energy storage unit and a negative transconductance unit. The energy storage unit forms a resonant cavity through an inductor and a capacitor; the negative transconductance unit is connected with the energy storage unit; the negative transconductance unit at least comprises a first cross-coupled pair and a second cross-coupled pair which are formed by a plurality of transistors; the first cross coupling pair is used for generating negative resistance to compensate the loss of the energy storage unit, and the second cross coupling pair serves as a current switching network; the first cross coupling pair and the second cross coupling pair form a negative resistance characteristic, direct-current energy is converted into alternating-current oscillation energy, loss of the resonant cavity is compensated, and a generated oscillation signal is output from the output node.

The embodiment of the application provides a voltage-controlled oscillator, an oscillator circuit, a chip and an electronic device, relates to the technical field of communication or radar detection, and can improve the linearity of the voltage-controlled oscillator. The voltage-controlled oscillator comprises a voltage-controlled oscillator resonant cavity, an even harmonic generator circuit and a self-mixing tripler circuit. The voltage-controlled oscillator resonant cavity comprises a voltage change diode array and a first mode switching capacitor. The even harmonic generator circuit comprises a group of cross-coupled tubes, one end of the group of cross-coupled tubes is electrically connected to differential two ends of the voltage-controlled oscillator, and the group of cross-coupled tubes simultaneously serves as an even harmonic generator and is electrically connected to the self-mixing tripler circuit. The self-mixing tripler circuit comprises a differential unit and a resonant cavity, and one end of the self-mixing tripler circuit is electrically connected to the even harmonic generator circuit. The low-frequency voltage-controlled oscillator and the self-mixing tripler circuit realize current multiplexing, the even harmonic generator circuit serves as an even harmonic generator of the self-mixing tripler in addition to serving as negative resistance of the oscillator, and the linearity of the millimeter wave frequency source is improved.

Embodiments of methods and semiconductor devices are described that are configured to determine a negative resistance margin (NRM) of an oscillator circuit. The semiconductor device may include an integrated circuit including an amplifier circuit coupled between a first node and a second node and NRM test circuitry including a resistor circuit selectively coupled between a first contact pad and the first node. The integrated circuit may receive an oscillating signal from an oscillator circuit coupled to the first contact pad and a second contact pad of the integrated circuit. In an NRM test mode, a resistance of the resistor circuit is selectively varied from an initial resistance value to one or more second resistance values and the oscillating signal is monitored at the second node to determine the NRM based on the one or more second resistance values when an amplitude of the oscillating signal falls below a threshold amplitude.

The invention relates to the field of integrated circuits, in particular to a K-band voltage-controlled oscillator based on a noise circulation structure, a phase-locked loop and a chip. The voltage-controlled oscillator comprises an oscillation circuit and a tuning circuit. The oscillating circuit comprises an upper resonant cavity formed by a basic oscillating circuit adopting a noise circulation structure and a lower resonant cavity formed by a noise suppression circuit adopting a Colpitts structure. The oscillating circuit adopts two groups of cross-coupled negative resistors, namely NMOS and PMOS, the cross-coupled negative resistors adopt a capacitance-coupled noise circulation structure, the PMOS adopts a Colpitts structure, and the cross-coupled negative resistors are connected through a tail inductor so as to improve phase noise and power consumption of the circuit. The tuning circuit adopts a variable capacitor which is connected to the oscillation circuit and is composed of a numerical control capacitor array and / or a self-adjusting capacitor circuit; and the capacitance value of the variable capacitor is adjusted to realize fine adjustment of the oscillation frequency. According to the invention, the problem that a traditional oscillator with a noise circulation structure is difficult to realize comprehensive optimization of phase noise and power consumption can be solved.

The present invention discloses an orthogonal single sideband mixer based on a passive negative resistance structure, belonging to the technical field of semiconductor integrated circuits. The orthogonal single sideband mixer comprises a first single sideband mixer (100), a second single sideband mixer (200), a first buffer (300) and a second buffer (400); wherein the first single sideband mixer (100) comprises a first mixing circuit (101), a second mixing circuit (102), a first adding circuit (103) and a first passive negative resistance (104); the first passive negative resistance (104) presents a normal LC structure in a small signal, has a low Q value and a wide operating frequency range; and presents a negative resistance characteristic in a large signal, increases the equivalent load Q value and enhances the frequency selectivity. The present invention has the advantages of taking both the operating frequency range and the frequency selectivity into consideration.

The present invention provides a GIS partial discharge detection device and method based on parity-time inversion symmetry. The device includes two parts: an LC sensor and a readout circuit. The LC sensor is composed of a parallel plate capacitor added with a charge adsorption material, an inductance coil, and a resistor connected in parallel. The LC sensor and the readout circuit perform energy coupling and signal transmission through inductive coupling. By adjusting the inductance, capacitance, and negative resistance parameters of the readout circuit, the LC sensor and the readout circuit are in the PT symmetry singular point position. When partial discharge occurs inside the GIS, the charge in the space increases, the charge adsorption material on the capacitor plates adsorbs the charge, the electrostatic force between the two capacitor plates increases, causing the distance between the two capacitor plates to change, the sensor capacitance changes, and a frequency splitting phenomenon appears. When the readout circuit system detects the system frequency splitting, it can detect the occurrence of partial discharge inside the GIS. The structure of the present invention is simple and has high sensitivity, which can improve the accuracy of partial discharge detection.

The present invention belongs to the technical field of wireless power transmission, and specifically relates to a wireless power transmission system operating in a ZCS with charging and blocking oscillation, including a power supply, a transmitting end and a receiving end, wherein the transmitting end has a resonant capacitor and a transmitting coil, and the receiving end has a receiving coil; the transmitting end also includes: an equivalent resistor, which is connected in series with the transmitting coil and in parallel with the resonant capacitor to form an energizing and blocking oscillation circuit; and a control switch, which is connected in series with the energizing and blocking oscillation circuit and connected to both ends of the power supply. The present invention realizes self-oscillation by adopting energizing and blocking, and blocks the resonant cavity after energization, so that the energy is enclosed in a closed-loop resonant circuit, and the energy will oscillate. Compared with the traditional self-oscillating WPT based on negative resistance, the present invention has fewer switching devices and does not require any additional circuit design, so it has better cost and robustness.