136 results about "Residual voltage" patented technology

The invention relates to a safe starting control method, device, equipment and medium for a bootstrap drive inverter, and the method comprises the steps: obtaining a detection voltage representing an output filter inductance voltage after responding to any starting event and before formally transmitting a drive signal; comparing the negative voltage with a preset negative voltage safety threshold value; only when the detected voltage is higher than the safety threshold, a driving enable signal is generated to allow the inverter to be normally started; otherwise, generating a driving blocking signal, carrying out detection and judgment again after waiting for preset time delay, and circulating the process until the system state enters the safe area; the method is realized by modifying a control algorithm, no power hardware needs to be added, the starting impact risk is eliminated with low cost, and the contradiction between the hardware limitation of a bootstrap drive circuit and the negative residual voltage possibly existing on the output inductance of the inverter is solved; therefore, the safety problem of direct connection between the impact current and the bridge arm during starting in an unfavorable initial state is solved.

The invention relates to the technical field of power fault detection, and mainly relates to a residual voltage detection circuit and a line protection device.The residual voltage detection circuit comprises a sampling circuit and a signal holding circuit, the signal holding circuit adopts double coils and comprises a first coil and a second coil, and a loop where the first coil is located is provided with a first controllable switch tube in series; the first controllable switch tube is connected when the sampling circuit collects residual voltage, a second controllable switch tube is arranged in a loop where the second coil is located in series, the control end of the second controllable switch tube is used for being connected with a feeder terminal, and the signal holding circuit further comprises a residual voltage output branch used for being connected with the feeder terminal. The residual voltage output branch is provided with a first contact of the double coils in series. A sampling circuit is used for obtaining a residual voltage signal generated at the moment of closing of a faulty power grid line, and a signal holding circuit formed by double coils is used for transmitting a sampling signal to a feeder terminal, so that the feeder terminal can still receive the residual voltage signal when the feeder terminal loses power after power supply is recovered.

The invention discloses a multi-physics field coupling high-resistance fault self-healing protection method, equipment and a medium. The method comprises the following steps: collecting multi-physics field coupling data and carrying out standardization processing; a multi-field coupling robust threshold value is generated based on the standardized multi-field coupling data, and the fault condition is further identified and judged; analyzing a fault condition based on a digital twinborn technology, inverting fault point data and performing multi-field cooperative adaptive arc extinction control; and self-healing recovery of robust optimization driving is carried out. According to the method, the dynamic protection threshold value is generated through a method of fusing time sequence prediction and robust optimization, wide-range fluctuation of new energy output and load can be automatically adapted, the problem that the misjudgment rate of a fixed threshold value is high when the system operation state changes is solved, and the dynamic adaptability of protection is improved; a model prediction control dynamic optimization active compensation strategy is adopted, the residual voltage and the residual current of a fault point can be actively restrained within a preset safety threshold value, and secondary accidents such as electric shock and mountain fire caused by incomplete arc extinction are avoided.

The invention provides a power converter, and belongs to the technical field of power electronics. In the scheme provided by the invention, the lightning protection unit in the power converter comprises a piezoresistor and a gas discharge tube which are connected in series. Therefore, the action voltage of the lightning protection unit can be effectively increased on the premise that the action voltage of the piezoresistor is not increased, and it is ensured that the lightning protection unit can be suitable for the high-voltage power converter. Moreover, by connecting the divider resistor in parallel with the gas discharge tube, flexible voltage division of the piezoresistor and the gas discharge tube can be realized, so that the model selection flexibility of the piezoresistor and the gas discharge tube is effectively improved. Besides, in a lightning stroke scene, the voltage at the two ends of the gas discharge tube after action is relatively low, and the residual voltage of the lightning protection unit can be prevented from being increased, so that the requirement on the protection performance of each power device in the power converter can be prevented from being increased.

The application provides a voltage converter. The voltage converter comprises a primary circuit, a secondary circuit and a discharge control unit. The secondary circuit comprises a first MOS tube and an output capacitor. The first MOS tube is connected with the discharge control unit. The discharge control unit is used for controlling the first MOS tube to work in a linear region when the voltage converter is in a shutdown state or an abnormal protection state. In the technical scheme, after the voltage converter stops working, the first MOS tube is controlled to work in the linear region, so that the first MOS tube consumes the residual voltage on the output capacitor in the voltage converter as a resistance. In this way, when the voltage converter is started, the pre-bias voltage is reduced or disappears, so that an excessively large reverse current is avoided, and thus the failure of components in the voltage converter is avoided.

The utility model relates to the technical field of switching power supplies, in particular to a starting circuit of a switching power supply, which comprises a starting input port, a power supply input port, a PWM (Pulse Width Modulation) control chip U1, a starting module, a power supply module and a linear voltage stabilizing module, the starting module comprises a capacitor C3, a resistor R12, a diode D2 and a switching tube Q2; the power supply module comprises a capacitor C2, a resistor R4 and a resistor R8; the linear voltage stabilization module comprises a switch tube Q3 and a resistor R5. According to the utility model, through the arrangement of the starting module, the power supply module and the linear voltage stabilization module, no residual voltage is transmitted to the power supply end of the PWM control chip U1 when the switching power supply is switched off, so that the power supply end of the PWM control chip U1 can be quickly initialized, and when the starting power supply is input at the starting input port again, the PWM control chip U1 can also be quickly and normally started.

The invention provides a method for improving PT residual voltage frequency measurement accuracy based on rotation vector characteristics, and relates to the technical field of generator set rotation speed measurement. The method comprises the following steps: acquiring a three-phase voltage alternating current signal through a generator end PT; processing the three-phase voltage signal to obtain projections of a voltage rotation vector on alpha and beta static coordinate axes; frequency characteristics are extracted based on projection and voltage amplitude and can be realized through direct calculation or a phase locking link; performing low-pass filtering on the frequency characteristic direct current quantity; a generator speed is calculated based on the filtered frequency and provided to a governor. According to the method, the limitation that a traditional PT residual voltage method only depends on zero crossing point information is broken through, frequency characteristics are extracted through a complete voltage sequence, alternating current signal filtering distortion is avoided through direct current filtering, high measurement precision and high anti-interference capacity can still be kept under the low-speed working condition, the problems that an existing speed measurement method is insufficient in precision and weak in anti-interference capacity are effectively solved, and the method is suitable for popularization and application. And reliable guarantee is provided for safe and stable operation of a unit.

The present application relates to aerospace, geological exploration and micro-light detection fields, and particularly relates to a reconfigurable noise shaping successive approximation register analog-to-digital converter, which comprises a sampling unit, a capacitive digital-to-analog converter array, a comparison unit, a passive noise shaping feedback unit, a successive approximation control unit, an output unit and a mode control unit. The sampling unit samples and holds an input signal, and the capacitive digital-to-analog converter array outputs to the comparison unit. The comparison unit compares its output with a common-mode reference voltage, and the result is sent to the successive approximation control unit. In the noise shaping mode, the successive approximation control unit additionally generates an integral clock timing to activate the passive feedback unit, samples a residual voltage and feeds back to the digital-to-analog converter array. The output unit drives the conversion result to a lower circuit. The present application also contains a method. The present application can effectively suppress the capacitive parasitic effect and low-frequency noise, realize flexible switching between high-speed conventional mode and high-resolution noise shaping mode, and significantly improve the system performance.

The invention discloses an adjustable self-bias closed-loop ring amplifier which comprises a first-stage MOS tube, a second-stage MOS tube, a third-stage MOS tube and a bias resistor unit, each stage of MOS tube comprises two MOS tubes, grid electrodes of the two MOS tubes of the first-stage MOS tube are connected and then connected with an input node, an output of the first-stage MOS tube is connected with grid electrodes of the two MOS tubes of the second-stage MOS tube, and the bias resistor unit is connected with the first-stage MOS tube and the second-stage MOS tube. The bias resistor unit is connected between drain electrodes of two MOS tubes in the second-stage MOS tube, partial voltage of the bias resistor unit is used for generating a first bias voltage and a second bias voltage, the first bias voltage and the second bias voltage are respectively connected with grid electrodes of two MOS tubes of the third-stage MOS tube, and an output end of the third-stage MOS tube is used for outputting voltage to a rear-end circuit. The adjustable self-biased closed-loop ring amplifier can quickly amplify residual voltage, is suitable for high-speed occasions, can also realize higher gain, and can work in a sub-threshold value by biasing the MOS tube, so that the stability of the adjustable self-biased closed-loop ring amplifier is improved. The invention further discloses a switched capacitor circuit comprising the adjustable self-biased closed-loop ring amplifier.

The application discloses a kind of transient diodes. Including: device main body;The device main body includes: at least one first bidirectional semiconductor chip, at least one second bidirectional semiconductor chip and conductive layer;The conductive layer is arranged between the first bidirectional semiconductor chip and the second bidirectional semiconductor chip, so that the first bidirectional semiconductor chip and the second bidirectional semiconductor chip are connected in series;Wherein, the first bidirectional semiconductor chip is N-type substrate bidirectional semiconductor chip, and the second bidirectional semiconductor chip is P-type substrate bidirectional semiconductor chip.The application provides a kind of transient diodes, realize to reduce transient diode residual voltage, improve the protection ability of device.

This invention discloses a multi-condition access, dynamic hierarchical switching, and event-related metering method and system for low-voltage emergency power supply. The method first collects data on the user-side interface residual voltage, original power supply isolation status, grounding status, emergency power supply output parameters, and load operating status, and then performs a multi-condition access determination. After successful access, a test load is connected to estimate the available power supply capacity and start-up impact margin under the current operating conditions. Next, loads to be restored are grouped according to load priority and electrical impact severity, and reserve margin verification and dynamic connection are performed for each group. After mains power is restored, loads are decoupled in reverse order and regular power supply is restored, outputting the event-related metering traceability results. This invention can improve the safety access capability, capacity utilization efficiency, and post-event traceability capability of low-voltage emergency power supply.

This application relates to the field of multi-column surge arrester technology, and in particular to a method for parallel connection and grouping of multi-column surge arresters, comprising the following steps: S1, performing aging screening and energy withstand tests on zinc oxide resistors of the same batch; S2, measuring the DC reference voltage U of each resistor. ref 0.75U ref Leakage current I0 under lightning surge, residual voltage U under lightning surge L and the residual operating voltage U under the operating wave S S3, select resistors in three stages; S4, operate the residual voltage U S The primary basis for grouping is a combination of high and low voltage resistors, ensuring that the residual voltage deviation of each series-connected resistor group is less than a first preset value and the DC reference voltage deviation is less than a second preset value. This rigorous selection process guarantees the consistency of resistor performance, and the reasonable grouping method makes the electrical performance of each resistor group more balanced. This improves the operating waveform withstand capability and current sharing characteristics of the multi-column surge arrester, reducing the probability of MOV failure due to uneven current distribution.

The utility model relates to the technical field of surge protectors, in particular to a graphite gap N-PE surge protector, which is characterized in that the graphite gap N-PE surge protector comprises a shell, a graphite gap module and a circuit module, the graphite gap module and the circuit module are both arranged in the shell, and the graphite gap module is arranged in the shell. The graphite gap module is connected with the circuit module; the circuit module comprises a boosting transformer, a voltage doubling circuit, an energy storage capacitor and a voltage division circuit which are connected in sequence, the boosting transformer is connected with the two ends of the graphite gap module, and the voltage division circuit is used for providing multiple trigger voltages and enabling the multiple trigger voltages to be changed in a gradient decreasing mode in the graphite gap module. Compared with a traditional surge protector, the surge protector provided by the utility model reduces the residual voltage of the graphite gap, improves the voltage protection level, and meets the requirement of a graphite gap module for small block motion threshold discreteness.

The application discloses a kind of wind-fire bundling system transient stability boundary construction method and device, method includes: based on the structure characteristics and operating characteristics of wind-fire bundling system, the equivalent model of wind-fire bundling system is established;Based on the operation of wind-fire bundling system in different fault stages, and in combination with the equivalent model, and the wind power generator set output and grid point residual voltage of wind-fire bundling system during fault low voltage ride through, determine the power and phase angle curve of wind-fire bundling system in different fault stages;Based on the power and phase angle curve of wind-fire bundling system in different fault stages, determine the stability margin of wind-fire bundling system about wind power generator set output and grid point residual voltage;Based on the stability margin about wind power generator set output and grid point residual voltage during fault, construct the transient stability boundary based on wind power generator set output and grid point residual voltage.The application can be according to wind power generator set output and grid point residual voltage, quickly and accurately judge whether wind-fire bundling system is located in stable region.

The invention provides a bus residual voltage holding device based on distributed reactive compensation, and belongs to the technical field of bus residual voltage holding of an electric power system, and the device comprises a short circuit fault identification module which is used for monitoring the current of the electric power system, and when a current amplitude criterion Ig is greater than or equal to 2Ie and a current change rate criterion di / dt is greater than or equal to 25kA / s, determining that a short circuit fault occurs; the exciting current switching module comprises a normal exciting current loop and a residual voltage regulation exciting current loop, and is used for switching exciting current into residual voltage regulation exciting current when a short-circuit fault occurs through switching of a switch K; according to the method, optimization and improvement are carried out from two aspects of fault judgment and fault recovery, and the time period from abrupt drop to recovery of the bus voltage is shortened; the large-area power failure risk caused by voltage instability can be greatly reduced, the power supply reliability of key livelihood facilities of hospitals, traffic, communication and the like is improved, and the social public safety and stability are maintained.

The invention belongs to the technical field of electric energy management, and discloses a control method for realizing bidirectional charging and discharging by using a unidirectional DCDC module. Comprising the steps that discrete operation signals of a one-way DCDC module are collected, data cleaning is carried out, and a discrete control parameter configuration set is obtained; working direction switching judgment is carried out, and a state switching control signal is output; shutdown confirmation is carried out, a shutdown request label is output to mark the discrete control parameter configuration set, and a safety switching control parameter set is obtained; capacitor residual voltage correction is carried out, and an effective state control signal is output; performing accurate load judgment, performing output frequency limiting adjustment, and generating a frequency limiting adjustment instruction; executing boost protection, and outputting discrete control signal parameters; and integrating the frequency limiting adjustment instruction and the discrete control signal parameters to construct a charging and discharging control strategy, and sending the charging and discharging control strategy to a preset DCDC module electric energy control terminal. The control reliability and the response accuracy are improved, and stable operation and safety are ensured.

The utility model discloses a kind of excess pressure controllers with multiple signal output, including machine body, cable being set in the top of machine body, the bottom end of cable extends to the inside of machine body connecting end and is electrically connected with machine body, the top of machine body is provided with first positioning frame located at the back of cable, the top of machine body is provided with second positioning frame located at the front of cable, first positioning frame and second positioning frame mutually adhere and extrude and fix to cable, the surface of machine body is provided with transmission frame. The utility model integrates cable fixing and advancing function, solves the problem of unstable plug-in, while the clamping action of first positioning frame and second positioning frame provides stable fixing effect, prevent cable loosening or displacement in subsequent operation, transmission frame design makes the entire clamping mechanism can be vertically lifted, ensure that the cable being clamped is smoothly pushed to the inside of machine body connecting end along predetermined direction, accurately deepen plug-in depth.

The utility model provides an integrated electronic protection device and a photoelectric sensor employing the same, the integrated electronic protection device comprises a housing, a Schottky diode and an array TVS tube are arranged in the housing, the array TVS tube comprises an N-type semiconductor substrate located in the housing and four first P-type base regions arranged on the surface of the N-type semiconductor substrate, and the four first P-type base regions are arranged on the surface of the N-type semiconductor substrate. First anode electrodes are arranged on the surfaces of the four first P-type base regions, and first metal layers capable of leading out pins are arranged on the surfaces of the first anode electrodes; compared with the prior art, the integrated electronic protection device has the following beneficial effects that the integrated electronic protection device is high in integration level and very small in size, so that the integrated electronic protection device can be applied to a miniature photoelectric sensor, the space is greatly saved, and surge voltage protection and power supply polarity protection are taken into consideration; in addition, the integrated electronic protection device in the utility model carries out surge voltage protection between lines, the residual voltage is relatively low, and the requirement on the withstand voltage of a post-stage circuit is not very high.

The embodiment of the invention discloses a surge protector and electronic equipment. The surge protector comprises a first protection device, a second protection device, a first auxiliary circuit and a second auxiliary circuit, the first end of the first protection device serves as the first end of the surge protector, the second end of the first protection device is connected with the first end of the second protection device, and the second end of the second protection device serves as the second end of the surge protector; the first end of the first auxiliary circuit is connected with the first end of the first protection device, and the second end is connected with the second end of the first protection device; the first end of the second auxiliary circuit is connected with the first end of the second protection device, and the second end is connected with the second end of the second protection device; and in the normal working state, the first protection device and the second protection device are controlled to be subjected to voltage sharing, and in the surge protection state, the first protection device and the second protection device are controlled to be conducted step by step. According to the scheme, the unification of high direct current withstand voltage and low residual voltage is realized.

This invention discloses a display panel detection circuit, detection method, and display device. In the display panel detection circuit, a pixel driving module stops outputting a first power supply to the first end of the light-emitting element during the panel detection stage. The panel detection stage sequentially includes a charging stage, a discharging stage, and a detection stage. A first storage module is connected in parallel with the light-emitting element. A detection control module connects a voltage writing module to the first end of the light-emitting element during the panel detection stage. The voltage writing module transmits a charging voltage to the first end of the light-emitting element during the charging stage and stops transmitting the charging voltage to the first end of the light-emitting element during the discharging and detection stages. The detection module outputs the residual voltage from the first end of the first storage module as a detection voltage to the controller during the detection stage. The technical solution provided by this invention can improve the detection capability of defective points in sub-pixels of the display panel.

A system and method for residual voltage monitoring and extracting ETI load parametric data relative to one or more electrodes of an implanted stimulation lead system associated with an IPG for diagnostics and for providing a medical therapy to a patient using electrical pulses. Responsive to comparing the measured residual voltages against estimated residual voltages obtained based on the ETI load parametric data, appropriate corrective action may be effectuated.

The invention discloses a power distribution network voltage sag sag domain analysis method considering distributed power supply access, and relates to the technical field of power system electric energy quality control. According to the method, a power distribution network asymmetric short circuit three-sequence equivalent model containing a distributed power supply and sensitive equipment is constructed, a looped network is split based on a voltage lowest node when a looped network structure exists, and a voltage sag sag domain general equation and a characteristic equation under any line fault condition are established; and further through sag subsystem division and Kron order reduction processing, an order reduction node impedance matrix about fault position parameters is formed, and the fault position parameters enabling the residual voltage of the sensitive nodes to reach a preset threshold value are determined by adopting an optimization iteration mode, so that the voltage sag sag domain boundary is accurately obtained. The method can give consideration to the calculation precision and efficiency, and is suitable for the voltage sag analysis of the power distribution network containing the distributed power supply and the complex topological structure.

The application provides a bus residual voltage detection method, a motor loss of voltage protection method, a storage device and a terminal. The bus residual voltage detection method comprises the following steps: constructing a mathematical model of motor counter electromotive force and a mathematical model of bus residual voltage initial value; based on the mathematical model, analyzing the change rule of the phase angle of the bus voltage to obtain a relationship expression between the differential quantity of the bus voltage space phase angle with respect to time and the rotor angular velocity; establishing a relationship expression between the motor speed and the motor rotor angular velocity; analyzing the motor speed and the rotor speed to obtain a relationship expression between the speed detection setting value and the motor speed during normal operation; and comparing the real-time collected rotor speed of the motor with the speed detection setting value to determine whether the bus voltage is the counter electromotive force of the motor. The application has the beneficial effect of achieving the motor loss of voltage protection according to the bus residual voltage characteristic quantity change and is suitable for the field of bus residual voltage detection.

The invention discloses a method and a system for processing poor shunting in CTC automatic pre-arrangement access, and relates to the technical field of railway transportation control, and the method comprises the steps: obtaining a residual voltage abnormal section mark which is used for marking a track section corresponding to poor shunting; before a pre-arrangement route instruction is generated, whether a residual voltage abnormal mark exists in a track section related to a route or not is judged; if yes, determining that the route relates to a poor shunt section, suspending information of the poor shunt section on a plan execution interface of a dispatcher terminal, and triggering a manual intervention mechanism; after manual intervention is completed, the CTC system executes the pre-arrangement route instruction; the processing method ensures safe and reliable execution of the CTC automatic pre-arrangement route function.

This invention discloses a surge protection circuit for gallium nitride (GaN) power devices in a power factor correction (PFC) circuit, aiming to solve the problems of insufficient surge resistance of GaN power devices and the high residual voltage of existing surge protection schemes, which easily leads to overvoltage breakdown of GaN power devices. A surge suppression unit is set between the rectifier circuit and the PFC main circuit. The surge suppression unit adopts a common-mode inductor containing a first coil L2A and a second coil L2B, coupled with a varistor VR4 in series, and is paired with capacitors C1 and C2 to form a π-type filter. Under normal operating conditions, it performs voltage filtering. During a lightning surge, VR4 breaks down, generating a surge current in L2A. The second coil L2B couples to generate a reverse electromotive force to offset the surge voltage, reducing the residual voltage at the input of the PFC main circuit. A primary protection unit assists in surge suppression. The PFC main circuit adopts a Boost topology and GaN power devices. This circuit has a simple structure, low cost, and high reliability, and is suitable for surge protection of outdoor GaN power supplies such as LED streetlights.

The utility model discloses a rapid wiring type surge protector. The rapid wiring type surge protector comprises a housing, a circuit board, a first terminal assembly and a second terminal assembly. An accommodating space and a terminal groove are arranged in the shell, and the circuit board is arranged in the accommodating space; each terminal assembly comprises a terminal base, a conductive terminal, an elastic clamping piece and a button. The terminal seat is provided with a terminal accommodating space and a wiring hole, and the elastic clamping piece is abutted between the conductive terminal and the inner wall of the terminal seat. The button is installed on the terminal base in a pressing mode, the button is pressed to enable the upper end of the elastic clamping piece to be separated from the conductive terminal, and the elastic clamping piece clamps the wire rod when the button is loosened. The circuit board, the terminal assembly and the conductive terminal are integrated in the shell, and the button, the elastic clamping piece and the conductive terminal are matched to realize quick disassembly and assembly of the wire rod; the piezoresistor circuit is used for filtering high-voltage surge, when the voltage exceeds a threshold value, the resistance is reduced, the discharge tube circuit breaks down to form a discharge loop, and common-mode protection is achieved; and the trigger circuit acts surge voltage on the discharge tube circuit to realize the characteristic of low residual voltage.

The utility model discloses an MOS tube fast turn-off control circuit, which comprises an MOS tube control circuit and a residual voltage discharge circuit, and is characterized in that the MOS tube control circuit comprises an MOS tube Q2, the source electrode of the MOS tube Q2 is connected with a grounding end, the drain electrode of the MOS tube Q2 is connected with one end of a load R4, the other end of the load R4 is connected with a VCC end, the residual voltage discharge circuit comprises a triode Q1, the collector electrode of the triode Q1 is connected with the grounding end, and the collector electrode of the triode Q1 is connected with the VCC end. The emitting electrode of the triode Q1 is connected with the second pin of the resistor R2, the first pin of the resistor R2 is connected with the grid electrode of the MOS tube Q2 and the base electrode of the triode Q1, the resistance value of the resistor R2 is 10 omega, and the base electrode of the triode Q1 is further connected with a PIN end. According to the utility model, rapid ground discharge of residual voltage between the grid electrode and the source electrode of the MOS tube is realized through the residual voltage discharge circuit at the grid electrode control input end of the MOS tube, rapid turn-off of the MOS tube during turn-off control is ensured, the reliability of turn-off control of the MOS tube is improved, and the MOS tube turn-off control circuit has the characteristics of simple structure, high reliability and low cost.

The application belongs to the technical field of integrated circuits, and particularly relates to a fourth-order delta-sigma modulator design method and system based on passive stacking. The application cascades a quantizer after a third-order active loop filter, and couples capacitors in parallel on the plate of a capacitor array of the quantizer. Sampling and quantization are performed in each cycle. The quantizer quantizes the output of the current loop filter. After quantization, the plate of the capacitor array naturally forms a residual voltage and stores the coupling capacitors. In the noise injection phase of the next cycle, the quantization error stored in the coupling capacitors in the last cycle is injected into the input end of the quantizer through charge redistribution, is weighted and superimposed with the intermediate signal to form the input voltage of the quantizer, and the main path attenuation coefficient and the coupling path gain coefficient are obtained through charge conservation analysis. A gain compensation factor is preset in the front-stage active integrator to offset signal attenuation, and the capacitor ratio is optimized to realize fourth-order noise shaping. The application does not require additional active circuits, has small area and low power consumption, and improves the signal-to-noise ratio.

The invention discloses a zone area photovoltaic equalization consumption control method and system based on energy storage, and relates to the technical field of photovoltaic equalization consumption, and the method comprises the steps: generating a topological fingerprint vector between a capacitor cabinet grounding point and an open triangle PT grounding point; generating a ground potential gradient vector according to the topological fingerprint vector and the residual voltage drainage current of the capacitor cabinet, and measuring the initial output voltage of the open-delta PT; according to the ground potential gradient vector, measuring a post-anchoring output voltage of the open triangle PT, and generating a post-anchoring potential lifting vector; and according to the initial output voltage, the output voltage after anchoring, the ground potential gradient vector and the potential lifting vector after anchoring, calculating a bias mapping constant corresponding to the common ground drainage effect in the target area. According to the invention, the photovoltaic localization utilization rate of the transformer area can be improved.

The application discloses a pipeline successive approximation analog-to-digital converter and a second-order gain error shaping method. The analog-to-digital converter comprises a first-stage successive approximation analog-to-digital converter, an inter-stage amplifier, a second-stage successive approximation analog-to-digital converter and a gain error shaping circuit. The method comprises the following steps: performing digital domain calculation on the output code value of the second stage in the last two periods to obtain a feedback code value; sampling and quantizing a first input signal to output a first digital code value; subtracting the feedback code value from the residual voltage of the first stage and amplifying the result through the inter-stage amplifier; performing backfilling on the second stage in a novel way to obtain a second digital code value; and integrating the first digital code value and the second digital code value to obtain an output code value. The application can suppress in-band leakage noise in normal working timing, and the novel backfilling method of the second stage avoids backfilling error generated in the backfilling process. The application can be widely applied in the technical field of mixed signal circuits.