517results about "Overload protection arrangements" patented technology

The invention discloses a capacitive voltage transformer for a gas insulated substation, which comprises a capacitive voltage divider and an electromagnetic unit, the capacitive voltage divider comprises a high-voltage capacitor C1 and a medium-voltage capacitor, the medium-voltage capacitor comprises a medium-voltage capacitor C21 and an externally connected medium-voltage capacitor C22, and the capacitance of the medium-voltage capacitor C22 is greater than that of the medium-voltage capacitor C21; the electromagnetic unit is connected with the capacitive voltage divider, an intermediate transformer and a compensation reactor are arranged in the electromagnetic unit, a full-shielding high-voltage shielding cover is arranged outside a high-voltage coil of the intermediate transformer, a damper and an overvoltage protector are arranged outside the electromagnetic unit, and the damper and the overvoltage protector are placed in an external junction box. The problem that in the prior art, an extra-high voltage transformer is low in lightning impulse overvoltage tolerance capacity is solved, the impulse overvoltage tolerance capacity is improved, and the breakdown risk is reduced.

The invention discloses a power adapter parameter dynamic optimization method for prolonging the service life of equipment, and relates to the technical field of adapter performance optimization, and the method comprises the steps: monitoring and recording the output voltage, current and power factor parameter changes of a power adapter in real time under static and dynamic load conditions by using a test instrument; identifying the trend and reason of abnormal parameter change; performing thermal design optimization and temperature management on the power adapter; performing over-power and over-current limitation on the pulses one by one; introducing a power factor correction circuit; optimizing the switching frequency and the design of an output filter; a load line adjusting circuit is introduced, and space is reserved for dynamic ripples when output current jumps; and evaluating whether the optimization effect reaches an expected target or not. By introducing the power factor correction circuit and the load line adjustment circuit, the power factor of the power adapter is improved, the harmonic pollution is reduced, the stability of the output voltage of the power adapter is improved, and the performance of the power adapter under the dynamic load condition is improved.

The invention provides a self-detection signal acquisition circuit based on analog quantity current and voltage mixed input, which comprises a surge protection circuit, a switch selection circuit, a clamping protection circuit, a follower circuit, an impedance matching circuit and an ADC acquisition chip which are connected in sequence, and also comprises a microcontroller, the microcontroller is connected with the ADC acquisition chip and the switch selection circuit, and the ADC acquisition chip is connected with the switch selection circuit. The microcontroller is used for acquiring the output voltage of the impedance matching circuit through the ADC acquisition chip, performing periodic detection on the output voltage of the impedance matching circuit, and periodically outputting a high level or a low level to the switch selection circuit based on the periodic detection result of the output voltage of the impedance matching circuit. Therefore, the switch selection circuit is controlled to switch gears. The technical problems that in the prior art, due to the fact that only a plurality of analog quantity signal input collecting modules of different types can be used for collecting a plurality of sensors with different output signals, the workload of sensor wiring work is large, the work efficiency is low, and the error rate is high are solved.

The invention discloses a rapid switching emergency protection system for an aero-engine test, and the system comprises a rapid switching unit which is used for rapidly disconnecting a DC load according to a switching instruction transmitted by a controller, and switching the DC load to an emergency protection load; the measuring unit is used for measuring signals such as engine gas turbine rotating speed, free turbine rotating speed, alternating-current voltage and current, direct-current voltage and current and the like; the controller is used for carrying out fault judgment on the system according to the measurement data acquired by the measurement unit and correspondingly sending a switching instruction to the rapid switching unit when a fault occurs; the monitoring system is used for monitoring and displaying parameters and operation states of the rectifier, the bus and the direct-current load system; and the emergency protection load is in circuit connection with the rapid switching unit and is used for providing the emergency protection load when the hybrid power system is in a large state and the load is suddenly lost. According to the invention, overspeed protection of a turboshaft engine hybrid power system test is realized, so that accidents such as breakage and flying-out of turbine blades are avoided.

The invention discloses a method for preventing needle burning during testing of breakdown voltage of a discrete device. According to the method, in a test loop comprising a probe card and a test source, a voltage-withstanding module is connected in series between the probe card and a low-potential end of the test source. The voltage-withstanding module comprises a detection resistor Rx and a voltage-withstanding switching device connected with the detection resistor Rx in parallel. When the test current I is applied, if the current is increased abnormally due to poor contact and the like, and the voltage drop on the detection resistor Rx is greater than or equal to the starting voltage VT of the voltage-withstanding switching device, the voltage-withstanding switching device is switched on, the test current I is shunted, and the current flowing through the probe card is reduced, so that the probe is prevented from being burnt. The breakdown voltage of the tested device is calculated by measuring the total voltage V at the two ends of the test source and subtracting the voltage drop (I * Rx) on the detection resistor Rx, and the test accuracy is ensured. The method can effectively protect the probe card and improve the test reliability and efficiency.

The invention belongs to the technical field of electronic measuring instruments, and particularly relates to an output protection method of a source meter, which comprises the following steps of: configuring an operation mode of a digital controller; executing closed-loop control of the main regulator; the arbiter continuously monitors the output state, and intelligently arbitrates and switches the main regulator, the clamping regulator and the output channel according to the measurement feedback value, the clamping threshold value and the over-limit threshold value, thereby achieving the precise clamping and over-limit protection of the output. By adopting the technical scheme, the flexibility, refined protection and adaptability of source table output control can be remarkably improved, the hardware cost is reduced, and the system reliability is improved.

The invention discloses a vehicle fault diagnosis circuit, a diagnosis method and a vehicle. The vehicle fault diagnosis circuit comprises an auxiliary diagnosis power supply circuit, a high-side sampling circuit, a low-side sampling circuit, a coil loop current detection circuit, a coil, a high-side switch and a low-side switch. The auxiliary diagnosis power supply circuit is connected with the coil loop current detection circuit, and the auxiliary diagnosis power supply circuit is used for controlling the on-off of an auxiliary diagnosis power supply; the coil loop current detection circuit is connected with the first end of the coil, the first end of the coil is connected with the high-side switch, and the coil loop current detection circuit is used for detecting the current of a coil loop; the high-side sampling circuit is connected with the first end of the coil, and the high-side sampling circuit is used for collecting the high-side voltage of the coil; the low-side sampling circuit is connected with the second end of the coil, the second end of the coil is connected with the low-side switch, and the low-side sampling circuit is used for collecting the low-side voltage of the coil.

The invention relates to a method for intelligently judging the type of a single-phase earth fault in a power supply and distribution system, which is suitable for connecting arc extinguishing equipment to a system bus and is parallel to each feeder line connected to the system bus. Wherein the working stage of the arc extinguishing equipment is divided into an arc extinguishing equipment awakening stage, a fault phase selection arc extinguishing stage and a fault type line selection stage. When a single-phase earth fault occurs in the range of a system line where the arc extinction equipment is located, the arc extinction equipment is quickly awakened and enters a fault phase selection arc extinction stage, and the single-phase earth fault occurring in the system line can be quickly processed through three links of phase selection, verification and arc extinction. And the method has the capabilities of fault tolerance, error correction and severe transient process suppression in the processing process. A three-phase split-phase switch driven by eddy current is selected as a phase selection switch in the arc extinction equipment, and the two-phase switch cannot be switched on or switched off at the same time due to disorder switching-on and switching-off programs when the arc extinction equipment performs phase selection action due to the wiring mode of each phase switch coil panel in the three-phase split-phase switch.

A DC electronic load circuit relates to the technical field of electronic load control. The utility model provides a direct current electronic load circuit which integrates a dissipation MOS tube array, an analog PID loop, a digital integrated control module, a bus electrical parameter sampling and processing module and a WiFi communication module, and realizes a plurality of working modes such as constant current, constant voltage, constant resistance and constant power by accurately controlling the conduction degree of the MOS tube array. The system has the advantages of real-time monitoring, remote control, overvoltage and overcurrent protection, low power consumption design and the like, and an electronic load solution which is high in precision, high in stability and flexible to operate is provided, so that diversified test requirements are met, and the power supply test efficiency and safety are improved.

The invention discloses a high-precision voltage regulating system of a power frequency no-partial-discharge test transformer, and the system comprises a heterogeneous multi-stage power module which is formed by connecting an H-bridge unit group and a matrix converter in parallel, the H-bridge unit group outputs a fundamental voltage component, and the matrix converter compensates a high-frequency harmonic component; the multi-physics field digital twinning unit integrates an electromagnetic field solver, a thermodynamic model and a mechanical deformation simulation module and predicts the multi-physics field coupling state of the insulation system in real time; the dynamic impedance matching network comprises an adjustable inductor array and a digital capacitor bank, and automatically adjusts filtering parameters according to a load impedance measurement value; and the control module is used for deploying a deep learning model and is used for optimizing a modulation strategy and a protection threshold on line. According to the method, the voltage regulation precision and the waveform purity can be improved, the stability under the wide-range working condition is guaranteed, the breakdown hidden danger is recognized in advance through multi-physics field coupling simulation, and partial discharge development is restrained from the source.

The invention discloses a back-to-back test platform for an energy storage converter, and relates to the technical field of converter testing, and the platform comprises a data collection module which employs a voltage source converter to access a power grid, and collects different load condition data; the capacitance health prediction module is used for constructing a deep learning model to extract features and calculating a fitness function to predict a capacitance state value; the redundancy control path module is used for constructing a redundancy control path to predict the state of the backup capacitor; and a load balancing module. According to the method, through the CNN-PSO-SVR model, real-time response can be carried out when the state of the capacitor changes, it is ensured that the attenuation state of the capacitor can be rapidly fed back to a control system, it is ensured that the capacitor continuously and stably operates under the complex load condition, power output is compensated in time through a redundant path, and the situation that the whole system is shut down due to the fault of a single element is avoided; through dual-path capacitor health monitoring and Droop-MPC dynamic power distribution, power output can be adjusted in time when early attenuation of the capacitor occurs, and system shutdown caused by a single-point fault is avoided.

The invention relates to the technical field of control systems, and particularly discloses an intelligent control system for an insulation test of a marine dry-type transformer. The system comprises a high-voltage test power supply module, a multi-mode sensing acquisition module, an insulation state evaluation module, a self-adaptive boost decision module and a test process control module, and evaluates an insulation state and dynamically decides a boost rate and a holding strategy by acquiring voltage, leakage current, partial discharge and temperature data in real time. Intelligent control and safety protection in the insulation test process are achieved, potential insulation damage is effectively avoided, and diagnosis precision is improved.

The invention relates to a high-voltage transformer series resonance withstand voltage test system and an automatic tuning method, and relates to the technical field of high-voltage electrical equipment testing, and the system comprises a control module, a signal generator, a resonance circuit, a data acquisition module and a safety protection unit. The method comprises the following steps: initializing system parameters; automatically searching and locking an optimal resonant frequency point; executing a withstand voltage test at the resonance point and monitoring data; and automatically analyzing data and judging performance. According to the invention, through full-closed-loop automatic control, rapid and accurate locking of the resonant frequency and intellectualization of the test process are realized, and the problems of low efficiency, poor precision and insufficient safety of a traditional method are effectively solved. The device has the outstanding advantages of high adaptive capacity, reliable test result and safety and convenience in operation, and is particularly suitable for high-efficiency and accurate standardized test on the insulating properties of various high-voltage transformers in an electric power system.

The invention discloses a composite voltage generation device and a cable insulation performance evaluation system and method, and relates to the technical field of high-voltage insulation testing. The composite voltage generating device comprises a synchronous controller, a direct current source, an impact source, an IGBT active protection unit and a magnetic isolation coupler, and by means of the excellent characteristics of the IGBT and the magnetic isolation coupler, the superposition time sequence accuracy of direct current and impact voltage is improved, and waveform distortion is reduced. The IGBT active protection unit comprises a first IGBT and a second IGBT, and direct-current voltage polarity switching can be realized through selective conduction of the IGBTs; the RC circuit is connected in parallel between the collector electrode of the first IGBT and the emitter electrode of the second IGBT, reverse current flowing back to the direct current source direction can be discharged through the RC circuit, the risk of energy flowing back is reduced, meanwhile, the magnetic isolation coupler can completely block direct current, and an impact source is protected against the influence of direct current voltage; according to the invention, the authenticity and reliability of cable insulation performance evaluation can be effectively improved.

A test and measurement device includes an input port to receive an input signal, a sampling circuit structured to generate a sample from the input signal, in which generating the sample from the input signal produces an amount of kickout energy, and an energy reducing circuit coupled between the sampling circuit and one or more other components of the test and measurement device, the energy reducing circuit structured to decrease the amount of kickout energy from the sampling circuit. The energy reducing circuit may include or be combined with a pick-off circuit. Methods are also described.

The invention relates to a power device driving fault detection circuit and a use method thereof. The power device driving fault detection circuit comprises a control circuit, an inverter circuit, a first comparator, a second comparator and a detection circuit, the control circuit outputs a complementary signal to drive a power device in the inverter circuit, and the inverter circuit supplies power to post-stage equipment and provides a voltage signal for the comparator; the first comparator detects grid and source voltage of the upper bridge power device, the second comparator detects grid and source voltage of the lower bridge power device, and results are input into the detection circuit. The detection circuit uses a logic gate to determine whether the upper and lower bridge arm power devices are simultaneously conducted or not so as to realize dead zone detection. According to the system, hardware circuits and excessive controller pins do not need to be added, the detection process is safe, and large current cannot be generated.

The invention relates to the technical field of power testing, in particular to multifunctional comprehensive test conversion integrated equipment which comprises a conversion integrated device and test instrument connecting line, a conversion integrated device and a multifunctional comprehensive test line. The conversion integration device and test instrument connecting line is used for connecting the conversion integration device and a test instrument; the conversion integrated device is used for quickly adapting to different test instruments and tested equipment and discharging before and after a test; and the multifunctional comprehensive test line is used for connecting the conversion integrated device and the tested equipment. Test items supported by the device are insulation resistance, dielectric loss capacitance, direct current resistance, transformation ratio and demagnetization tests, all power failure routine test items of the transformer can be completed without replacing a test line, the time of the power failure routine test of the transformer and the frequency of high-altitude operation can be obviously reduced, the working efficiency is greatly improved, and the test cost is reduced. And the safety risk in the test operation process is reduced.

The invention discloses a high-precision voltage and current characteristic quantity extraction and anti-interference sampling circuit compensation method, and belongs to the technical field of voltage and current sampling, and the method comprises the steps: employing a 24-bit ADC to collect voltage and current signals at the sampling frequency of 1 kHz to 10 kHz; electromagnetic interference is inhibited through the metal shielding cover and the wave absorbing material; dynamically correcting the sampling data through a temperature compensation model; dynamically correcting the sampling data based on an LMS algorithm; voltage and current effective values are calculated through a root mean square algorithm in a sliding window mode, a processing result is output in real time, and the problems that existing sampling precision is low and the error compensation effect is limited are solved.

The invention discloses a converter valve half-bridge sub-module short-time overvoltage test method and a related device, and the method comprises the steps: forming a charging current to charge a sub-module capacitor based on a sub-module twin-trawling loop through an external connection capacitor tower test loop, simulating a DC side sub-module capacitor voltage rising state, and achieving a certain voltage; and the pressure relief protection branch circuit of the power module acts to realize multiple times of release of surplus energy of the capacitor of the half-bridge sub-module of the flexible direct current converter valve and verification of an overvoltage protection function. According to the test method, the tested sub-module is large in short-time energy, the energy release state of the tested sub-module is similar to that of an engineering sub-module, a plurality of sets of high-power capacitor towers are adopted to synthesize a plurality of single-periodic charging currents based on a sub-module twin-trawling loop, and therefore repeated continuous overvoltage is achieved, and the energy release function and the reliability of a voltage release protection branch are verified.

The invention discloses a digital closed-loop oscillation protection circuit, method, electronic load and system, the circuit comprises an oscillation signal acquisition circuit, the oscillation signal acquisition circuit comprises a sampling unit and a coupling capacitor unit, the sampling unit is used for acquiring current and / or voltage data of a closed-loop control circuit, and the output end of the sampling unit is connected with the coupling capacitor unit; the control module is used for outputting a control signal of the closed-loop control circuit, the output end of the coupling capacitor unit is connected with the signal input end of the control module through a first ADC, and the control module judges whether oscillation occurs or not according to the amplitude of the alternating-current component signal and stops output of the control signal to close the closed-loop control circuit under the condition that oscillation occurs. Oscillation protection can be realized without arranging a fuse, and the protection response time is short.

The invention relates to a low-level direct drive test system and test method. The system comprises a signal processing device, a signal generation device, a power amplifier protection device and a signal acquisition device. The signal processing device is connected with the signal generation device and the power amplifier protection device, the output end of a power amplifier in the signal generation device is connected with the power amplifier protection device, the power amplifier protection device is connected with the test end of the aircraft to be tested, and the signal acquisition device is arranged on the aircraft to be tested and connected with the signal processing device; the signal processing equipment is used for controlling the signal generation device to output a test signal, and processing and analyzing the state data of the to-be-tested aircraft acquired by the signal acquisition device to obtain a test result; and the power amplifier protection device is used for monitoring a signal at the output end of the power amplifier and protecting the power amplifier. The power amplifier is protected, so that the power amplifier outputs a stable test signal, and the stability of a test result is improved.

The invention provides a voltage drop acquisition circuit, a power device driving circuit and electronic equipment, and belongs to the technical field of electronics. The voltage drop acquisition circuit is suitable for acquiring the conduction voltage drop of the power device. The target device is a device on a desaturation protection path of the driving chip; the voltage sampling unit is connected with the first node and the second node of the target device, and the first node or the second node of the target device is suitable for being connected with a power device; the voltage sampling unit is used for collecting node voltages of the first node and the second node, converting the node voltages into a conduction voltage drop of the power device, and outputting the conduction voltage drop. According to the invention, the conduction voltage drop of the power device can be monitored in real time.

The invention discloses an oscillation protection circuit, an electronic load, a power supply test system and equipment, the circuit comprises a switch module and an oscillation detection circuit, and the switch module is connected with a control signal input end of a closed-loop control circuit; the oscillation detection circuit comprises a sampling unit, a coupling capacitor unit, a Schmitt trigger and a D latch, the sampling unit is used for sampling the voltage and / or current of the closed-loop control circuit, and the output end of the sampling unit is connected with the input end of the coupling capacitor unit so as to be used for obtaining an alternating current component in the sampled voltage and / or current; the output end of the coupling capacitor unit is connected with the input end of the Schmitt trigger, the output end of the Schmitt trigger is connected with the first input end of the D latch, and the output end of the D latch is connected with the control end of the switch module. Fuses and software control are not needed, the protection response time can be shortened, and the reliability of oscillation protection is improved.

The invention relates to the technical field of power system energy storage equipment testing, in particular to a small and medium-sized industrial and commercial energy storage cabinet twin-trawling testing system which comprises a main loop, a secondary control loop and an anti-countercurrent detection unit, the main loop comprises double testing loops and four sets of alternating current contactors, and multi-machine twin-trawling testing frameworks such as one-to-one, one-trawling-two and one-trawling-three can be flexibly combined; independent switching between grid connection and grid disconnection is supported, the secondary control loop comprises a button with a lamp and a grouping reset button, and the countercurrent prevention detection unit detects the energy flow direction in real time through an intelligent electric meter and a current sensor and has a mains supply charging function. According to the test system, through a double-loop parallel test architecture and a multi-machine flexible combination design, the system can be synchronously butted with multiple energy storage cabinets to carry out parallel test, the test efficiency can be improved, and a safety system with anti-countercurrent detection, rapid mode switching and precise control protection guarantees the test safety; the arrangement of the standardized terminal and the button with the lamp simplifies the operation difficulty, and reduces the test threshold.

The utility model provides a KGD dynamic parameter test device for a silicon carbide MOSFET. The coaxial test line is used to connect the detection board and the dynamic test host. The coaxial test line can achieve a distributed inductance of nH level. For example, under the condition of a length of 1 meter, a distributed inductance of less than 30nH can be achieved, so that the device under test can achieve a higher test current, a slighter bus voltage drop, and a higher short-circuit energy during a short-circuit test, and a lower voltage spike can be achieved when the device under test is turned off; the probe protection circuit is arranged close to the test board, and the probe protection circuit is a current balancing and overcurrent protection circuit, which can play a role in uniform current for each group of probes and limit the maximum current of each group of probes. When the device under test is damaged during the short-circuit test, before the bus power supply protection responds (1μs~5μs), the probe protection circuit can first synchronously clamp the maximum current of the probe, thereby protecting the probe from being burned out.

This application relates to the field of chip design technology, disclosing a chip edge integrity detection circuit and a chip. The chip edge integrity detection circuit includes a metal loop, a detection circuit, and a protection circuit. The metal loop is disposed around the perimeter of the chip. The detection circuit is connected to the metal loop and configured to detect impedance changes in the metal loop to determine the integrity of the chip edge. The protection circuit is connected to both the metal loop and the detection circuit and configured to protect the circuit. In this application, the detection circuit provides an objective damage assessment method. By setting the parameters of the detection circuit, the impedance changes of the metal loop can be quantitatively analyzed, thereby quantitatively analyzing the degree of chip damage. This improves the accuracy of judging the degree of chip damage, reduces the situation where a minor chip damage is mistaken for complete chip failure, and improves chip yield.

The utility model provides an over-current protection circuit of skin detector, including over-current detection element, switch module, current amplifier and singlechip, over-current detection element and switch module series connection in skin detector's main circuit, current amplifier's input terminal connects over-current detection element and switch module's contact, the output terminal connects singlechip, current amplifier's current amplifier is connected with the singlechip, current amplifier's current amplifier's current amplifier's current amplifier's current amplifier's current amplifier's current amplifier's current amplifier's current amplifier's current amplifier's current amplifier's current amplifier's current amplifier's current amplifier's current amplifier. The level output end of the single-chip microcomputer is connected with the controlled end of the switch module. When the skin detector is used, the switch module is conducted to enable the main circuit of the skin detector to start to work, the current amplifier amplifies a current signal flowing through the current detection element at the moment and then inputs the current signal into the single chip microcomputer, and if the amplified current is larger than a preset protection value, it means that the working current of the skin detector is too large; therefore, the single-chip microcomputer outputs high level to the switch module through the level output end of the single-chip microcomputer, so that the switch module is switched off, a main circuit of the skin detector is switched off, and the skin detector is prevented from working in an overcurrent state.

Systems and methods provided herein relate to a power system, such as a system for a motor. A digital acquisition unit is configured to receive current sense signals associated with a motor and phase voltage power signals associate the motor. The data acquisition unit includes a module coupled to a first ground and an attenuator circuit coupled to a second ground. The first ground is isolated from the second ground. The phase voltage power signals are provided to the attenuator, and the attenuator provides phase voltage sense signals to the module.

The invention provides a power supply PCB detection device and method, and relates to the technical field of electronics, and the method comprises the steps: an impedance detection module detects the first impedance of the input end of a to-be-detected power supply PCB and the second impedance of the output end of the to-be-detected power supply PCB, and transmits an impedance detection result to a processing module; the power-on test module is used for supplying power to a power supply PCB to be tested, collecting a first output voltage under a no-load condition, and transmitting a power-on test result to the processing module. The on-load test module connects the output end of the to-be-tested power supply PCB to a load, tests a second output voltage, and transmits an on-load test result to the processing module; the processing module judges whether short circuit abnormity exists according to the impedance detection result, judges whether no-load performance is abnormal according to the power-on test result, and judges whether on-load performance is abnormal according to the on-load test result. By implementing the technical scheme of the invention, the effect of improving the detection efficiency of the power supply PCB is achieved.

The utility model discloses a device for isolated measurement of voltage and current input, which belongs to the technical field of current and voltage measurement, and comprises an isolation module, a voltage measurement module, a current measurement module, a control module and an analog-to-digital converter module, the isolation module is respectively connected with the control module and the analog-to-digital converter module, and the analog-to-digital converter module is connected with the isolation module. The voltage measurement module and the current measurement module are respectively connected with the analog-to-digital converter module, and the analog-to-digital converter module comprises a measurement chip U1. According to the utility model, through the isolation module, when current signals and voltage signals are measured, field side signals are electrically isolated from the system, so that the reliability and the stability of the system are improved.