420 results about "Average current" patented technology

The invention provides a welding method and device, electronic equipment and a storage medium, and belongs to the technical field of intelligent manufacturing. A target wire feeding speed corresponding to the actual average current value is determined according to the target compensation relation; the actual wire feeding speed is adjusted to the target wire feeding speed; the target compensation relation is determined from the compensation relation set based on the target average current value, and the target compensation relation comprises the corresponding relation between the actual average current value and the target wire feeding speed. Through the pre-established compensation relation, the wire feeding speed can be actively adjusted in the welding process according to the deviation of the monitored actual average current value so as to compensate the deviation in real time, and therefore it is guaranteed that the heat input amount in the whole welding process is constant, and the welding quality is improved. The technical problems of welding current fluctuation and inconsistent welding seam forming caused by dry elongation change due to factors such as out-of-roundness of workpieces are solved, and the quality and reliability of welding seams are remarkably improved.

The invention discloses a method for predicting the remaining driving range of a pure electric vehicle. The method comprises the steps that original data of the vehicle within a preset time span are collected and processed; training a joint prediction model according to the original data, and obtaining a predicted battery health state through the joint prediction model; training a mileage prediction model according to the combined prediction model and the original data; the charge state variation of the charging section is obtained, and the actual consumed energy of the battery is calculated according to the charge state variation and the predicted health state of the battery; obtaining the current environment temperature, obtaining predicted non-driving demand energy according to the original data and the current environment temperature, and calculating driving demand energy; and obtaining a prediction segment according to the driving demand energy, and inputting the working condition information, the average current and the residual electric quantity variation of the prediction segment into the mileage prediction model to obtain the residual driving mileage. According to the method for predicting the remaining driving range of the pure electric vehicle, the remaining driving range can be predicted in combination with the low-temperature environment and the battery recession condition, so that the prediction accuracy is improved.

The invention belongs to the technical field of integrated circuits, and particularly relates to a stepping motor current control method and device. The control circuit is used for an H-bridge motor driving circuit, the four switches of the H bridge control the working state of the motor under the control of the driving signal, and in one PWM period, the four switches of the H bridge are controlled to enable the average current of the load to be equal to the set current. According to the stepping motor current control method provided by the invention, the load average current in a PWM period can be completely equal to the set current, and the error of the angle position of the stepping motor is reduced. The invention also provides a stepping motor control device for correspondingly realizing the attenuation mode.

The invention relates to the technical field of electric tool control, in particular to a motor control method of a target electric tool and a motor control circuit executing the motor control method, and the method comprises the steps: obtaining peak current at a detection resistor and a current PWM signal duty ratio, calculating real-time average current according to the peak current and the current PWM signal duty ratio, and comparing the real-time average current with an average current threshold value; and adjusting the duty ratio of the PWM signal according to the result, and outputting the PWM signal to drive the motor according to the adjusted duty ratio. By dynamically adjusting the duty ratio, the stability and safety of the electric tool under high load are effectively improved, the operation experience is optimized, the hardware upgrading requirement can be met, and the use bottleneck is broken through.

The invention discloses a control module and an adapter, and the control module is used for determining the input current of a buck circuit and the output voltage of a loop compensation circuit. According to the relationship between the output voltage and the input current, controlling the turn-off of a switching tube of the buck circuit; wherein the turn-on duty ratio of the switching tube is in direct proportion to the quotient of the output voltage and the average value of the input current. According to the invention, the turn-on duty ratio of the buck switch tube is proportional to the quotient of the output voltage and the input average current of the loop compensation circuit, and power factor modulation can be realized, so that an input voltage sampling resistor and a corresponding multiplier are omitted.

The invention provides an acceptance test method and system for a substation station end. The method comprises the steps that current test data and voltage test data of a plurality of power monitoring lines marked at the station end of a substation are acquired, the current test data comprise current monitoring coefficients of the power monitoring lines, and the current monitoring coefficients are related to line average current values, current vector deviations and line monitoring current variances; the voltage test data comprises a voltage monitoring coefficient of each power monitoring line, and the voltage monitoring coefficient is related to a voltage vector deviation and a voltage average achievement deviation; and according to the current test data and the voltage test data, abnormity monitoring is carried out on each power monitoring line to obtain line abnormity classification data, then line abnormal points are positioned to obtain position data of the line abnormal points, and line abnormity early warning is issued. According to the method, the problem of low acceptance efficiency caused by difficulty in simultaneous fault positioning of a plurality of test abnormal positions in the prior art is solved.

A converter circuit may require sensing an average current as feedback for regulating the average current supplied to a load. Sensing the average current may be inaccurate due to the non-ideal behavior of devices in the converter circuit. The disclosed circuits and methods help to improve the accuracy of the sensed average current by ignoring portions of a PWM cycle. Some of the ignored portions are based on a peak threshold for a rising current of a PWM cycle and a valley threshold for a falling current of a PWM cycle. The peak threshold and the valley threshold may be adjusted to control the average current and the switching frequency of the converter circuit.

The invention discloses a control method and a control device for neutral-point potential balance. The method comprises the following steps: acquiring a three-phase modulation signal and a bridge arm current corresponding to the three-phase modulation signal; the sizes of the three-phase modulation signals are compared, and the maximum value umax, the minimum value umin and the intermediate value umid of the modulation signals are determined; the bridge arm current corresponding to the three-phase modulation signal is compared, and the maximum value imax, the minimum value imin and the intermediate value imd of the bridge arm current are determined; according to the minimum value u < min >, the intermediate value u < mid > and the maximum value u < max > of the modulation signal, the boundary value of the zero-sequence voltage u < z > is calculated; determining a direction factor kz of the zero-sequence voltage uz according to the intermediate value umid of the modulation signal and the intermediate value imid, the minimum value imin and the maximum value imax of the bridge arm current; and according to the boundary value of the zero-sequence voltage uz and the direction factor kz, adjusting the average current inpv of the injected midpoint so as to control the potential balance of the midpoint. According to the technical scheme, the program storage space of the control method for neutral-point potential balance is reduced, and the program running speed of the control method for neutral-point potential balance is increased.

The invention relates to the field of electrical variable measurement, in particular to an opening and closing current detection method and system for a switch cabinet circuit breaker, and the method comprises the steps: increasing a sampling frequency T1 to a sampling frequency T2 when the average change amplitude of the current is greater than a preset threshold value F1, collecting the current again through T1 when the current collected through T2 and the current collected through T1 have the same change rule, if the current time is changed from the high-frequency time period to the low-frequency time period, changing F1 by utilizing the change rule similarity of the current in the low-frequency time period and the high-frequency time period obtained recently on the basis of a threshold F2, and if the current time is changed from the low-frequency time period to the high-frequency time period, changing F1; and the F2 is changed by using the similarity b of the change rules of the current in the low-frequency time period and the high-frequency time period obtained in the last two times, and opening and closing parameters are read from all the collected opening and closing currents and detected. According to the invention, the current generated by transient switching-on and switching-off actions can be accurately captured from a large amount of interference current.

Disclosed herein is a pulse generator device for trigeminal nerve stimulation. In one embodiment, the pulse generator device comprises a processor(s) configured to: produce pulses delivered to an electrode assembly for a therapy session(s) for a patient, log data from the therapy session(s) (where the data comprises impedance of the electrode assembly connected to the pulse generator and current amplitude of the pulses), determine an average current amplitude from the data, determine an average therapy impedance from the data, determine a charge capacity of a battery of the pulse generator prior to beginning a subsequent therapy session, determine whether the charge capacity of the battery is sufficient to complete the subsequent therapy session for a designated duration of time by using the average current amplitude and the average therapy impedance. Further the pulse generator device comprises a display configured to display a screen comprising a graphical user interface (GUI).

The invention discloses a fault diagnosis method, device and equipment for an NPC three-level inverter and a medium, and relates to the technical field of inverter fault diagnosis, and the method comprises the steps: building a fault stator current analysis model according to a fault stator current change rule of the inverter; a fault phase and a fault bridge arm are extracted and positioned by using a sliding window averaging method; and calculating and setting a fault positioning reference value under an ideal condition, and comparing the fault positioning reference value with a fault positioning actual value under an actual condition to position a faulted IGBT (Insulated Gate Bipolar Translator). A fault stator current analysis model is established to simulate a set current change condition under an ideal condition, a fault positioning reference value is calculated, and whether an actual fault condition is consistent with a set ideal fault condition is distinguished by a deviation between the fault positioning reference value and a fault positioning actual value of an actual condition, and whether a fault is an inner pipe or an outer pipe is positioned. During calculation, a current mean value from a fault moment to a first zero-crossing moment is utilized, a fault IGBT can be positioned in a fundamental wave period, and fault diagnosis and positioning can be quickly and efficiently carried out.

The invention discloses a peak current sampling circuit suitable for a DC / DC converter with a wide load range, and belongs to the field of switching power supply DC / DC converter control. The circuit comprises a power PMOS switch tube P1, a power NMOS tube N1, an inductor L1, a sensing resistor RS, a sensing capacitor CS, an output capacitor COUT, divider resistors RFB1 and RFB2, a sampling circuit, a low-pass filter, a differential amplifier, an adder / subtractor, a transconductance amplifier, a compensation resistor RC, a compensation capacitor CC, a PWM comparator, a slope compensation circuit, an oscillator, an RS trigger and a logic and driving circuit. An equivalent series resistor DCR of an inductor is utilized, and a low-pass RC sensing network is connected to two ends of the inductor in parallel to sense an inductive current, so that power consumption caused by a traditional sampling resistor RSENSE is eliminated, and the efficiency of the DC / DC converter is improved; through reasonable arrangement of the values of the sensing resistor RS and the sensing capacitor CS and an internal signal processing circuit, an inductance ripple current signal is amplified on the basis of retaining the inductance average current, the sampling signal-to-noise ratio is improved, and noise interference is reduced.

The embodiment of the invention discloses a circuit and method for measuring the average current of an electromagnetic valve, and belongs to the technical field of automotive electronics. The circuit comprises an electromagnetic valve, a first power supply, a sampling resistor, a field effect transistor driving circuit, a current acquisition circuit, an integral circuit and an integral reset circuit, the field effect transistor driving circuit is used for controlling the on-off state of the first field effect transistor based on the pulse width modulation gating signal; the first power supply is used for providing driving current for the electromagnetic valve under the condition that the first field effect transistor is in a conducting state, and the driving current flows through the sampling resistor; the current acquisition circuit is used for sampling voltage signals on two sides of the sampling resistor and outputting the voltage signals to the integrating circuit; the integral circuit is used for performing integral processing on the voltage signal and determining the average current of the electromagnetic valve based on an integral result; and the integral reset circuit is used for performing periodic reset processing on the integral circuit based on the pulse width modulation gating signal.

A system comprising a current sensor for sensing an average output current and / or an average input current of a circuit is presented. There is a first switch, the first switch being arranged to selectively couple a sensing node of the circuit to a first voltage, wherein the current sensor comprises a pulse density modulator configured to generate a pulse density modulated signal. The pulse density modulated signal is dependent on an average current flowing through the first switch. The current sensor is configured to sense the average output current and / or the average input current of the circuit using the pulse density modulated signal.

The invention provides a current sampling method, a current sampling control device and a robot. The current sampling method comprises the following steps: acquiring a first sampling value and a second sampling value which are obtained by performing current sampling on a motor by a first sampling circuit and a second sampling circuit respectively; the sampling precision of the first sampling circuit is lower than that of the second sampling circuit; and when the first sampling value is smaller than a first threshold value, performing weighted average on the first sampling value and the second sampling value by using the first weight and the second weight to obtain a current value after weighted average as a current sampling value of the motor. The current sampling precision of the motor can be improved.

According to the control circuit and the control method of the vehicle charger disclosed by the invention, the rectifier bridge of the bridge PFC is removed, so that the number of switching devices is reduced, the topological cost is reduced, and the loss is reduced; power factor correction is realized through average current control, and stable 400V direct current is output for post-stage power supply after power grid side 220V alternating current is rectified; the rear-stage resonant converter is highly symmetrical in structure and has the advantages of high power density, strong energy interactivity, input and output isolation and easy realization of soft switching; a hybrid modulation strategy is adopted for the resonant converter, frequency modulation and extended phase shift segmented modulation are adopted under the normal load condition, the problem that the frequency modulation range is narrow during voltage reduction is solved, intermittent Bang-Bang charge control is switched under the light load condition, and the problems that the output voltage drift is high and the efficiency is reduced during light load are solved; therefore, the charging efficiency of the vehicle-mounted charger is improved.

Disclosed is a system for zero voltage switching in a power converter with a first half-bridge and a second half-bridge. The first half-bridge has a first set of transistors and output inductor. The second half-bridge has a second set of transistors and auxiliary inductor. A current sensing means measures, at switching cycle scale, average and maximum current values of output inductor and average, minimum and maximum current values of auxiliary inductor. A voltage sensing means measures input and output voltages of first and second half-bridge. A controller is configured to compute dead times of pulse width modulation control signal of second half-bridge, generate pulse width modulation control signal of second half-bridge and to adapt dead times of first half-bridge.

The invention relates to the technical field of backlight control, in particular to an LED display-oriented adaptive PWM backlight control method and a backlight driving system, which are suitable for the backlight driving system comprising a boost converter, a brightness controller and an LED channel, and the method comprises the following steps: the brightness controller outputs a control voltage, a peak current control word and a duty ratio signal, and receives a state signal. Receiving brightness data, determining a nominal peak current and a duty ratio, and initializing the nominal peak current and the duty ratio; adjusting the control voltage to change the boost output, monitoring the state, locking the working point when all states are converted from the first state to the second state, and taking the final switching channel as a reference; a peak current word is increased for the non-reference channel under the working point, and when the state returns to the first state from the second state, an optimized peak current is taken back; and adjusting the duty ratio according to the ratio of the nominal peak current to the optimized peak current to enable the average current of each channel to be consistent. According to the invention, the problem that excessive voltage drop of a linear current regulator causes extra power consumption and heating and influences the brightness consistency between channels is solved.

The invention discloses a high-stability and low-ripple high-voltage direct-current converter. The high-voltage direct-current converter comprises a full-bridge inverter circuit, a resonant filter circuit, a transformer and a voltage-multiplying rectifying circuit which are connected in sequence, wherein the voltage-multiplying rectifying circuit is formed by cascading a plurality of voltage-multiplying modules; the output ends of the plurality of voltage-multiplying modules are connected in series to form high-voltage direct current output; each voltage-multiplying module is formed by connecting a plurality of voltage-multiplying units with a bus capacitor in parallel after the inputs and outputs of the voltage-multiplying units are connected in parallel; all the bus capacitors are sequentially connected in series and then connected with a load. According to the voltage doubling rectifying circuit in the scheme, under the condition that the voltage level of a device is not increased, the current average value and the voltage variation on a capacitor are reduced, and output ripples are reduced; and meanwhile, when the load changes, the total output voltage variation is reduced, the voltage regulating range of the resonant cavity is reduced, and the stability of the output voltage is improved.

The invention provides a group black start method and device of a multi-machine parallel energy storage system and the energy storage system, and belongs to the field of energy storage. The method comprises the following steps: acquiring a positive sequence feedback current average value, a negative sequence feedback current average value and group black start given voltage of the energy storage system; performing current-sharing control based on the positive-sequence feedback current average value and the negative-sequence feedback current average value to obtain a positive-sequence average current control quantity and a negative-sequence average current control quantity; performing positive sequence voltage control based on the positive sequence average current control quantity and group black start given voltage to obtain given output current; based on the negative sequence average current control quantity and the given output current, current control is carried out, and a target control quantity is determined; and controlling the corresponding energy storage converter to perform synchronous black start based on the target control quantity. According to the invention, synchronous black start of each energy storage converter can be realized, sequential start is not needed, a lot of time can be saved, and the power of the energy storage system can reach an expected output level.

A converter circuit may require the sensing of an average current as feedback to regulate the average current supplied to a load. Due to the non-ideal behavior of the devices in the converter circuit, the sensing of the average current may be inaccurate. The disclosed circuits and methods help improve the accuracy of the sensed average current by ignoring portions of a PWM cycle. Some of the ignored portions are based on a peak threshold for a rising current of a PWM cycle and a valley threshold for a falling current of a PWM cycle. The peak threshold and valley threshold can be adjusted to control the average current and switching frequency of the converter circuit.

The invention discloses a fault detection method and system for an integrated double-gun direct current charging pile, and relates to the technical field of charging pile fault detection, and the method comprises the steps: obtaining a real-time order of the integrated double-gun direct current charging pile, and carrying out the analysis and processing of the real-time order of the integrated double-gun direct current charging pile based on a fault analysis terminal. According to the method, the historical order of the integrated double-gun direct current charging pile is analyzed to determine the historical change curve of the charging current, and then the real-time order of the integrated double-gun direct current charging pile is analyzed to determine the real-time change curve of the charging current. The charging current real-time change curve and the charging current historical change curve are calculated and analyzed, the average current change quantity is determined, finally, the average current change quantity is judged, whether the integrated double-gun direct current charging pile has the overcurrent phenomenon or not is determined, the situation that the integrated double-gun direct current charging pile breaks down in the charging process is avoided, and the charging efficiency is improved. The spontaneous combustion condition is avoided, and the property loss is reduced.

The invention relates to an active power factor correction device, in the active power factor correction device, an average current controller and a feed-forward compensation controller are respectively used for obtaining a first duty ratio and a second duty ratio, a duty ratio processor is used for superposing the first duty ratio and the second duty ratio to obtain a total duty ratio, the pulse width modulation controller is used for generating a pulse width modulation signal for controlling the switching device according to the total duty ratio, the second duty ratio is related to the sum of inductive currents sampled for multiple times in a power frequency period, and the sum of the inductive currents changes along with the load power of the main circuit. Therefore, the second duty ratio can reflect the dynamic change of the load power, the total duty ratio is obtained by superposing the first duty ratio and the second duty ratio, the feedback can be enhanced when the load power changes, and compared with the control by only using the average current method, the control capability on the output voltage and the input current is improved, and the control efficiency is improved. And a better power correction effect can be realized.

The invention relates to a charger test overload protection method and system, and relates to the technical field of charger overload protection testing, and the method comprises the steps: collecting and monitoring a detection current when a charger is tested, and carrying out the calculation according to a preset threshold value calculation strategy when the detection current is at a preset safety current critical value, so as to determine a safety threshold value; comparing the safety threshold value with a preset danger threshold value, and when the safety threshold value is equal to or greater than the preset danger threshold value of the overload protector, indicating a preset test current adjusting device to perform test current adjustment; the calculation formula of the threshold value calculation strategy is as follows: # imgabs0 # # imgabs1 #, S represents the safety threshold value, Iavg represents the average current in a period of time, Imax represents the maximum allowable current of the charger, T represents the time length, and I (tau) represents the instantaneous current at the tau moment. The method and the device have the effect of reducing the probability of short circuit in the charger inspection process.

The invention discloses a switching power supply and an average current sampling circuit thereof, and the circuit comprises a real-time current sampling circuit (1) which samples the real-time current flowing through an upper switch (NM1) / lower switch (NM2); a holding signal generation circuit (3) for generating the holding signal at more than half of the time of each conduction period of a first control signal / a second control signal on the basis of the first control signal of the upper switch (NM1) / the second control signal of the lower switch (NM2), the conduction period being a time period in which the control signal controls the corresponding switch to be conducted; the sampling and holding circuit (2) is used for receiving the holding signal and holding and outputting the current sampled by the real-time current sampling circuit (1) at the half conduction period moment; according to the invention, the sampling current is enough for the establishment of the sampling circuit from the inductive current at the beginning of the sampling conduction period to the more than half time of the conduction period, so that the error caused by the establishment time is avoided, and more accurate inductive average current sampling is realized.

The invention belongs to the technical field of battery charging and discharging, and discloses a bidirectional DC-DC inductive current digital sampling correction method and system.The method comprises the steps that electrical parameters of a converter are obtained, input power is calculated, meanwhile, the set working mode of the converter is judged, the working state of the converter is analyzed according to the set working mode, and the output power of the converter is calculated; calculating a duty ratio feed-forward coefficient and an inductance average current correction coefficient in combination with the electrical parameters; and calculating an inductive current average value based on the inductive average current correction coefficient and the inductive current sampling value, substituting the inductive current average value and a duty ratio feed-forward coefficient into a loop, calculating an actual duty ratio, and driving a power tube to work. On the basis of classical voltage and current double-closed-loop control, a duty ratio feed-forward control algorithm is added, the response speed of the system is improved, meanwhile, based on a duty ratio feed-forward coefficient, an inductive current digital sampling correction method is provided, the sampling accuracy of the inductive average current is improved, and then the performance of the battery charging and discharging test system is improved.

The invention describes a driver circuit for supplying a constant current to an LED arrangement (LED1... LEDN) formed by a buck converter comprising a current measurement resistor (Rsense) in series with a coil (Lbk) that measures the current through the coil (Lbk). A two-point control circuit turns on or off the first switching element (Qh) as a function of a measured current (Vsense) flowing through the coil (Lbk) in order to keep the average current flowing through the LED arrangement (LED1... LEDN) constant. A current amplifier circuit (A sense) is connected to a current measurement resistor (R sense) to detect a current (V sense) flowing through the current measurement resistor, and positive and negative currents can be measured by superimposing an offset voltage (V offset) applied to one of its inputs by an offset voltage source. An output terminal of the current amplifier circuit is connected to an input terminal of the two-point control circuit. The offset voltage (V offset) is also superimposed on its threshold voltage (V peak, V valley). Furthermore, a start-up pulse circuit (Vstart-up) is provided, which is connected to the control input of the first switching element (Qhs) via a diode (Dstart-up).

The embodiment of the invention provides a multi-path parallel BUCK circuit and a control method, and belongs to the technical field of current conversion. The control method comprises the following steps: acquiring the output current of each branch circuit connected in parallel; determining the average current of each branch according to the current; judging whether current sharing control is needed at present; calculating an adjustment error according to the current error of the current branch under the condition of judging that the current sharing control is needed; calculating an increment value according to a formula (1); and adjusting the current branch according to the increment value. According to the circuit, the capacitors of the multiple BUCK units are shared, parallel connection of the multiple BUCK units is achieved, and the design size of equipment is reduced. According to the control method, the current output by each path is sampled and calculated, comprehensive monitoring of the circuit is achieved, finally, feedback control of the circuit is achieved in combination with calculation of the current, and therefore the control efficiency is improved.

The invention discloses an air conditioner and a power estimation device, a power estimation method and a controller thereof. The air conditioner comprises a compressor, a fan, a compressor IPM module used for driving the compressor, a fan IPM module used for driving the fan, a passive voltage doubling circuit used for providing direct current for the compressor IPM module and the fan IPM module, and a direct current bus capacitor used for smoothing the direct current. The detector is used for detecting DC bus voltage; the current detection circuit is used for detecting the average current of the compressor and the average current of the fan; and the controller is used for estimating the compressor power according to the direct-current bus voltage and the compressor average current, estimating the fan power according to the direct-current bus voltage and the fan average current, and summing the compressor power and the fan power to obtain the power of the air conditioner. The device can estimate the power of the air conditioner, does not need to detect the input current in real time, and is high in applicability.

Current regulation circuits and techniques. In one example, a circuit includes a voltage regulator circuit, current sensing circuitry, and a current control loop. The voltage regulator circuit is coupled to an output terminal of a DC-DC power converter and configured to produce a regulation signal based on a voltage at a regulator input terminal. The current sensing circuitry is coupled to a switching terminal of the DC-DC power converter and configured to produce a pulse signal based on a voltage at the switching input terminal and a threshold set by the regulation signal. The current control loop is coupled to control terminals of switching transistors of the DC-DC power converter and configured to generate switching control signals, based on the pulse signal, to control the switching transistors to drive an average value of a current flowing through the switching terminal to a target average current value corresponding to the threshold.