65results about How to "High protection precision" patented technology

The invention relates to a monitor for a hoisting machine, which comprises a rotary encoder for detecting displacement of the hoisting machine and outputting impulse signals corresponding to the displacement of the hoisting machine, a control unit for calculating speed of the hoisting machine by using the impulse signals received from the rotary encoder, and a mode selecting module for switching the control unit between a standard mode and an actual operational mode, wherein in the standard mode, the control unit records the calculated speed of the hoisting machine as standard speed, and in the actual operational mode, the control unit compares actual speed of the hoisting machine calculated at a preset position with the standard speed corresponding to the preset position, so that the control unit sends out stop signals to stop the hoisting machine when a difference value of the actual speed and the standard speed is larger than a first threshold value. The monitor has the advantages of simple structure, high precision and wide appliance range.

The invention discloses a ground fault line selection method based on high-frequency component correlation. The method comprises the following steps: S1) monitoring a zero sequence voltage value of an exit of each power distribution line in real time, and if the zero sequence voltage value is larger than a limit value, judging a power distribution network has a ground fault, and collecting zero sequence current of each line; S2) carrying out denoising processing on the zero sequence current of each line to obtain a pure fault component ; S3) carrying out EMD decomposition on the pure fault component to obtain various transient frequency components, and then, through instantaneous frequency analysis, removing a power frequency component and extracting a corresponding high-frequency transient component; and S4) carrying out pairwise correlation analysis on the high-frequency transient component of each line to obtain a correlative coefficient matrix M, and solving integrated correlation coefficient [rho]i of each line. The ground fault line selection method has the advantages of simple principle, high anti-interference capability and high protection precision and the like.

The invention provides a pulsating DC (direct current) aftercurrent protector and a running method thereof. The protector comprises a switching device, a microprocessor, a zero sequence current transformer, an aftercurrent signal amplifying circuit and a power supply, wherein the output of the zero sequence current transformer is connected with the aftercurrent signal amplifying circuit; the output of the aftercurrent signal amplifying circuit is connected with the microprocessor; the switching device is connected with the microprocessor; the input of the power supply is connected with a power grid; and the output of the power supply and the microprocessor are connected with the switching device. The protector can distinguish the types of aftercurrent waveforms and adopts the different protective measures in accordance with the different types of the aftercurrent waveforms, thus improving the protection accuracy; and the protector is suitable for the aftercurrent protection of the power grid with different frequencies or can be used for realizing the accurate aftercurrent protection when the frequency of the power grid is changed, thus expanding the application occasions of the protector. The protector is simple in structure, small in volume and very low in power consumption.

The invention relates to the technical field of explosion-proof devices for high-voltage cable joints, and specifically relates to a simulation method for the opening radius of an energy release holeof a high-voltage cable joint explosion-proof device, which comprises the following steps of: adopting COMSOL Multiphysics multi-physical field coupling simulation software to construct models of different types of energy release hole explosion-proof devices; adopting the mode of heat-flow-solid multi-physical field coupling, calculating the maximum gas velocity and pressure distribution in the explosion-proof chamber corresponding to the design of different radii of the blowout holes; according to the exponential function law, obtaining the function relation between the maximum pressure and the size of the energy dissipation hole in the explosion-proof device by the least square method. Considering the secondary damage caused by the reduction of the maximum pressure inside the explosion-proof device and the reduction of the jet flow through the vent hole, the optimized radius of the vent hole is designed. The invention can optimize the size design of the energy dissipation hole of theexplosion-proof device of the high-voltage cable joint, save the test cost, improve the protection precision, and provide a reliable theoretical calculation method for the explosion-proof device design.

The invention discloses an alternating current dynamo imbalance protection method based on unblanced accumulation. The method is conducted according to the following steps. Firstly, three-phase load current of an alternating current dynamo is collected, and the unbalancedness at the moment is figured out. Unbalancedness accumulation coefficients between grade points corresponding to unbalancedness are counted; accumulated dynamo unbalancedness increment of the dynamo within specified time and accumulated value of unbalancedness of the current time are calculated, respectively by using corresponding accumulation coefficients of all points; the accumulation value of unbalancedness of the current time is compared with the set threshold of strip to determine whether the stripping relay is triggered and to protect the dynamo. The invention method adopts the unbalancedness accumulation model to prevent the dynamo from imbalance; and piece-wise linearization method is adopted to adjust the unbalancedness accumulation coefficient DC dynamically, and imbalance protection precision of the alternating current dynamo is significantly improved.

The invention relates to a circuit protection device, a circuit protection method, and a piece of circuit protection equipment. The circuit protection device comprises a first switch coupled between a load and a power supply used for powering the load, and a controller coupled to the first switch. The controller is used for switching off the first switch when judging that an abnormality occurs according to a first signal, and switching on the first switch when judging that the abnormality is eliminated according to a second signal and a third signal, wherein the first signal indicates the current flowing through the load when the first switch is switched on, the second signal indicates the power voltage of the power supply, and the third signal indicates the load voltage of the load. By adopting the circuit protection device and the circuit protection method provided by the invention, an abnormal state can be identified accurately, over-current protection can be provided, the circuit can recover from the over-current protection state in a timely manner, and almost no security risks exist.

The invention discloses an encoding method, a decoding method, an encoding device and a decoding device for a virtual machine command, and a virtual machine protection system.The encoding method comprises the steps of when compiling a program to be compiled, randomly modifying a command encoding format of the virtual machine command of the program to be compiled; and generating a rear end output command of a compiler according to the randomly modified command encoding format.

The invention discloses an external circuit breaker tripping control device of an electric energy meter. The external circuit breaker tripping control device comprises an electric operating unit and more than one circuit breaker unit. The loop of each circuit breaker unit is provided with a wiring board. The wiring board is a shunting component for detecting current. The shunting part of the wiring board is connected with a sampling current lead and performs sampling on a current signal in a sampling loop. A current signal is transmitted to a main wiring board of an electric operating unit. The main wiring board performs analysis and comparison on a detected current signal, thereby determining a normal load current or an overload current. On the condition that the current is the overload current, a CPU on a main circuit board transmits a tripping instruction, thereby driving an electric operating mechanism to trigger tripping of the circuit breaker and realizing overload protection of the circuit breaker. According to the external circuit breaker tripping control device, a bimetallic strip and related components in a traditional circuit breaker are replaced, and a circuit board is utilized for performing overcurrrent determining, thereby realizing higher protection precision, no debugging on the circuit breaker and high convenience in production.

The invention relates to an energy-saving type intelligent controller and the control method thereof, which comprises a display module, a monolithic processor, a human body infrared sensor, an integrated operational amplifier, a comparator and an optical coupler. The output terminal of the sensor is respectively connected with the two input terminals of the comparator through a voltage follower with time delay function and a reference voltage obtained by dividing the voltage through two resistors, after being compared, two signals are input into the input terminal of the optical coupler by the output terminal of the optical coupler, the output terminal of the optical coupler outputs the signals to the input terminal of the monolithic processor, and after being judged, the signals whether or not are displayed are input into the display module. Because the invention leads a light activated element to be arranged in the controller and to be processed by a circuit, when people stand in front of the controller, a liquid crystal display screen enters a display state, when no person stands, the controller does not enter into the display module, the signal processing chip of the controller keeps in the dormant state, and the controller only protect and detect a power distributing network. In the way, the power consumption of the controller is greatly decreased, the operating time is shortened, and the protection precision of the controller is improved.

The invention discloses an inverse time current limiting electrical fire prevention and control device and method. The device comprises a control unit, a solid-state switch, an analog signal conditioning circuit and a current detection unit used for detecting instantaneous alternating current information of the protected loop. The output end of the current detection unit is connected with the input end of the control unit through the analog signal conditioning circuit. The output end of the control unit is connected with the solid-state switch. The protected loop is connected with a power supply through the solid-state switch. The device and the method have the inverse time characteristic, and the volume is small.

The invention discloses a DC line breakage protection method of a multi-end flexible DC power distribution system. With regard to different running modes of open loop and closed loop of the multi-endflexible DC power distribution system, the fault characteristic thereof during a DC line breakage fault is analyzed, on the basis, the difference between the fault level and the non-fault level is further amplified by taking sum and difference of currents of a fault level circuit and a non-fault level circuit as division, and the purpose of reliably identifying the fault level circuit is achieved.The DC line breakage protection method is applicable to a condition that the DC line breakage fault occurs in the multi-end flexible DC power distribution system under different running mode, the situation that line breakage protection is difficult to achieve due to unobvious line breakage fault characteristic is prevented, and rapid fault identification and pole selection can be achieved according to local measurement information.

The invention provides an intelligent circuit breaker, which comprises a housing, a first wiring end, a second wiring end, a handle, a tripping linkage mechanism, an electromagnetic tripper, a movingcontact, a static contact, a bimetal sheet, a current transformer, a drive mechanism, a first driving member, a second driving member, a first connecting member, a second connecting member and a circuit board. The moving contact is corresponding to the static contact. The intelligent circuit breaker can solve the problem that a traditional circuit breaker is poor in protection precision and incomplete in protection, realizes a distribution protection function and meanwhile, realizes intelligent control of the intelligent circuit breaker, can carry out on/off control according to power demand,and can also realize local or remote centralized monitoring management, thereby improving power distribution safety and intelligence degree.

The invention is an electronic thermal relay, composed mainly of shell, terminal, reset button, indicator light and circuit device, where the circuit device is arranged in the lower part of the shell, a measurer is arranged in the upper part of the shell and provided with equipment instruction electromagnetic control relay, single-phase double-metal thermal component and Hall component to detect traveling distance of the single-phase double-metal thermal component, and the circuit device includes a protecting circuit, composed mainly of IC (integrated circuit), the Hall component is connected with the IC, the measured signal of the Hall component instructs the electromagnetic control relay to act through IC operation instruction equipment. Its switching-on and -off are clear and the current overload protection for the motor is effective and accurate.

The invention provides a master control board of a human-machine interactive sports car. The master control board comprises a master control module, a power module, an external power interface, a charge and discharge module, a motor driving module and a sensor module. The charge and discharge module is in connection with the external power interface, the power module and the motor driving module. The charge and discharge module is also used for connecting with battery packs. The sensor module comprises a gyroscope, an acceleration sensor and a hall sensor. The gyroscope is used for detecting declination information of a car body; the acceleration sensor is used for detecting acceleration information of the car body; the hall sensor is used for detecting velocity information of the car body. The sensor module is connected with the master control module, the PWM driver interface of the master control module and the motor driver module. The master control module is used for receiving the declination information, the acceleration information and the velocity information, performing data fusion, and outputting a drive signal to the motor driving module, the driving module drives a motor to revolve according to the drive signal, and the safety coefficient is high. The invention also relates to a control system of the human-machine interactive sports car.

The invention discloses an electronic multi-sectional overcurrent protection device and relates to the technical field of protection of molded case circuit breakers and molded case residual current operation circuit breakers. The device is provided with a winding L1; a short-circuit protection element consisting of a static armature, a movable armature, a roller pin and a resetting torsional spring is arranged at the upper end of the winding L1; a bent part is arranged at the upper end of the static armature symmetrically; a limiting groove A is formed at one end on the inner side of the bentpart; a limiting groove B is formed in the middle of the bent part; a winding L2 and a winding L3 are arranged at the lower end of the winding L1; the winding L1 is a primary side winding, and the winding L2 and the winding L3 are secondary side windings; the head of the winding L2 is connected with the tail of the winding L3; and the tail of the winding L2 and the head of the winding L3 are voltage signal output ends. The electronic multi-sectional overcurrent protection device has the advantages of setting or adjusting an overcurrent protection operation value on site, and remotely setting or controlling in combination with corresponding equipment.

The invention discloses a high-precision and high-reliability LED vehicle lamp driving circuit. The circuit comprises a bias module, an error amplification module, a current detection compensation module, a pulse width modulation module, a PWM control module, an output driving module, an oscillator module (OSC), a high-precision high-reliability undervoltage protection circuit (UVLO), a high-precision high-reliability overvoltage protection circuit (OVLO), a high-precision wide-voltage-range over-temperature protection circuit (OTP) and a power switch NMOS tube MG. According to the driving circuit provided by the invention, on one hand, the common-mode interference detection circuit is adopted in the temperature protection circuit, so that common-mode noise interference is avoided, and the protection precision is improved; and on the other hand, a power supply burr detection circuit is adopted in an overvoltage protection circuit and an undervoltage protection circuit, a reset signal is output under an abnormal condition, a protection signal is locked in advance, and the reliability of the circuit is improved. The invention can be widely applied to various high-voltage integrated circuit chips.

The invention relates to a current-based longitudinal differential protection method and system for a belt conveyor, which are used for protecting the belt conveyor during operation. The method comprises the following steps of periodically collecting the current value of the belt conveyor, and judging whether the belt conveyor is in no-load operation or not, if yes, protecting the belt conveyor through the no-load protection step, and if not, protecting the belt conveyor through the load protection step. Compared with the prior art, the method has the advantages of high accuracy, high reliability, good safety, strong timeliness and the like.

The invention discloses a charger, which comprises a single chip microcomputer, a voltage output module, a relay, an output voltage detection module and a battery voltage detection module, wherein a first end of the relay is connected with the voltage output module and the output voltage detection module separately and a second end of the relay is connected with the battery voltage detection module and a battery separately; the voltage output module, the output voltage detection module, the relay and the battery voltage detection module all are connected with the single chip microcomputer; the output voltage detection module is used for detecting a voltage value of the first end; the battery voltage detection module is used for detecting a voltage of the second end; and the single chip microcomputer is used for adjusting the voltage value output by the voltage output module through adjusting the duty ratio of a square wave of the single chip microcomputer when the voltage value of the first end is different from the voltage value of the second end, so that the voltage value of the first end is the same as that of the second end. The charger has higher reliability.

The invention provides a current signal output circuit for a microcomputer protection device and the microcomputer protection device. The current signal output circuit comprises an input resistor, a signal amplifier, a sampling resistor, a differential circuit and a negative feedback resistor, one end of the input resistor is connected with an external to-be-converted voltage end, the other end of the input resistor is connected with a reverse input end of the signal amplifier, an output end of the signal amplifier is connected with a non-inverting input end of the differential circuit, and two ends of the sampling resistor are respectively connected with the non-inverting input end and the reverse input end of the differential circuit. One end of the sampling resistor connected to the reverse input end is a current output end, the current output end is connected with an external supply circuit, one end of the negative feedback resistor is connected with the output end of the differential circuit, and the other end is connected with the reverse input end of the signal amplifier. The microcomputer protection device solves the technical problems that a current signal transmission circuit of a microcomputer protection device in the prior art is sensitive to temperature change and electromagnetic interference, and meanwhile the signal precision and response speed are poor.