315 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 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.

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 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.

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.

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 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.

A controller circuits and methods are provided that control a power converter. A controller comprises a voltage control loop circuit, a current control loop circuit, and a peak current control loop circuit. The voltage control loop circuit is configured to receive a first input and a second input and generate a first output signal representing an error between the first input and the second input. The current control loop circuit is configured to receive the first output signal and a first reference signal and generate a second output signal. A peak current control loop circuit is configured to receive the second output signal and a second reference signal and generate a third output signal that sets the duty cycle.

The invention discloses a parallel formation low-bandwidth pulse switching control method and device and a storage medium, and the method comprises the following steps: predicting an initial duty ratio according to the voltage relation of Buck-Boost topology; generating a feedforward prediction duty ratio through a feedforward compensation mechanism; dynamically selecting a loop switching mode according to a current error absolute value or a current change rate, and determining a current loop duty ratio; the loop switching mode comprises a current open-loop control mode and a current closed-loop control mode; when the loop switching mode is a current closed-loop control mode, a PI parameter is dynamically adjusted according to a current error value; and when the current average change rate and the current error meet the compensation condition, the current loop is controlled to enter steady-state control. According to the invention, the current switching speed and precision are obviously improved, the step response overshoot is greatly reduced, and the steady-state error minimization is ensured.

The application relates to a cable current correction measurement method based on an open-loop structure TMR sensor, which comprises the following steps: S1, installing TMR sensors S1 and S2 on an open-loop mechanical structure; S2, obtaining a magnetic field strength vector of a magnetic field excited by a cable current at positions of the sensors S1 and S2, and obtaining a magnetic field strength component in the direction of a sensor sensitive axis through vector operation; S3, obtaining a mathematical equation about unknowns introduced by only the sensor S1; S4, solving the nonlinear mathematical equation established in the step S3 to obtain a cable current value; S5, judging whether the obtained current value meets a preset condition, if yes, storing the current value, otherwise, continuing to perform optimization calculation; S6, discarding unreasonable current values after a sample capacity N is reached; S7, fitting sample current values by using an interpolation polynomial, and finally obtaining an average current value. Compared with the prior art, the application has the advantages that the cable current value can be effectively calculated.

The application discloses a pinch-proof current threshold calculation method, system and device, and a storage medium. The pinch-proof current threshold calculation method comprises the following steps: dividing the whole Hall stroke into multiple Hall regions according to current characteristics; collecting current data in a complete motor motion process multiple times in each Hall region to obtain multiple sets of current data of each Hall region; setting a pinch-proof current threshold of each Hall region according to the multiple sets of current data of each Hall region; in each motor motion process, calculating a current average current value of each motor motion through a corresponding Hall region, and judging whether the current average current value changes relative to the last average current value; if the current average current value changes, the pinch-proof current threshold of the Hall region is recalculated and updated; otherwise, the pinch-proof current threshold does not change. The application can dynamically adjust the pinch-proof current threshold, and solves the problem that the motor current characteristics change with the use time, resulting in the failure of the pinch-proof function.

The invention belongs to the technical field of wind power generation, and particularly relates to a wind-solar complementary power generation system fault diagnosis and identification method and system.The method comprises the steps that voltage, current and surface temperature data of a storage battery pack are collected in real time, and the current change rate at the current moment is calculated; when the current change rate exceeds a set threshold value, marking the current moment as an impact starting point, and intercepting data before and after the impact starting point to form an impact time window; in the impact time window, based on the current variable quantity of each moment, the temperature correction factor corresponding to the surface temperature and the window average current, constructing a load impact strength index of each moment by using a logarithmic function, and constructing a voltage recovery elasticity index of each moment in combination with a standard deviation of voltage fluctuation in the impact time window; and comparing the voltage recovery elasticity index with a preset health threshold to judge whether the storage battery is normal or failed. According to the invention, the accuracy and reliability of fault diagnosis are improved.

A circuit and method for measuring an average current of a solenoid valve, relating to the technical field of automotive electronics. The circuit comprises a solenoid valve (110), a first power supply (120), a sampling resistor, a field effect transistor drive circuit (130), a current acquisition circuit (140), an integrator circuit (150), and an integration reset circuit (160); the field effect transistor drive circuit (130) is used for controlling an on-off state of a first field effect transistor on the basis of a pulse width modulation gating signal; the first power supply (120) is used for providing a drive current for the solenoid valve (110) when the first field effect transistor is in an on state, and the drive current flows through the sampling resistor; the current acquisition circuit (140) is used for sampling voltage signals on two sides of the sampling resistor, and outputting the voltage signals to the integrator circuit (150); the integrator circuit (150) is used for performing integration processing on the voltage signals, and determining an average current of the solenoid valve (110) on the basis of an integration result; and the integration reset circuit (160) is used for performing periodic reset processing on the integrator circuit (150) on the basis of the pulse width modulation gating signal.

The utility model discloses a power supply circuit and device and electric equipment, the power supply circuit comprises a plurality of power supply modules, each power supply module comprises a power supply unit, a current sampling unit, a current sharing unit and a feedback unit, and the output end of the power supply unit is used for being connected with a load; the input end of the current sampling unit is connected with the load; the current sharing unit is used for outputting reference voltage according to the average current of the plurality of power supply modules; the feedback unit is used for outputting a first feedback signal to the power supply unit according to the reference voltage and the first sampling voltage output by the current sampling unit, so that the power supply unit adjusts the output power supply voltage according to the first feedback signal; the power supply circuit can meet the power utilization requirement of the load for high power.

The embodiment of the invention discloses a method and system for evaluating the charge elimination performance of ionization equipment and computer equipment. The method comprises the following steps: acquiring the duration of each sampling period and the average current of a polar plate capacitor connected with ionization equipment in each sampling period; obtaining a voltage change value of the polar plate capacitor in each sampling period based on the duration of each sampling period and the average current of the polar plate capacitor in each sampling period; generating a voltage-time curve of the polar plate capacitor based on the initial voltage and the voltage change value of the polar plate capacitor in each sampling period; and obtaining an evaluation result of the charge elimination performance of the ionization equipment based on the voltage-time curve. The problems that at present, an accurate and efficient method for evaluating the electricity elimination performance of the ionization equipment is lacked, and the actual electricity elimination capacity of the ionization equipment under different working conditions is difficult to accurately judge are solved.

Current limits are set for detecting anomalous current drain of a battery in an electrical system during a Key-Off state of a vehicle. A plurality of test vehicles are selected which are operational without any anomalous current drain. A plurality of time intervals are identified according to a plurality of predetermined Key-Off-Load (KOL) modes which are activated successively after initiation of the Key-Off state. Key-Off interval currents are measured during each of the time intervals in each of the test vehicles. A respective average current of the interval currents is determined in each respective time interval. A respective standard-deviation current of the interval currents is determined in each respective time interval. A respective current limit is set corresponding to each time interval according to the respective average current plus a respective incremental value determined according to the respective standard-deviation current.

Sensorless propeller damage detection systems and methods may receive and process motor quadrature-axis currents to extract current ripples and fast average current values. In addition, the current ripples and fast average current values may be further processed to generated normalized rms (root-mean-square) values of the current ripples. Further, the calculated values may be compared to one or more threshold values over a time duration to determine whether a propeller is damaged. In this manner, the sensorless propeller damage detection systems and methods may quickly, reliably, and accurately detect propeller damage without any additional sensors or dedicated hardware and with low computational cost, while also minimizing false positive determinations of propeller damage.

The application discloses a rudder shaft hole key groove electric spark machining method and a machining system, and belongs to the technical field of electro-hydraulic rudder machining. The problems of low rudder shaft qualification rate, low machining efficiency and high machining cost are solved. The electric spark machining method comprises a rough machining process and a rounding process. In the rough machining process, a first electrode is configured on an electric spark machining device, and the electric spark machining device processes a key groove in the rudder shaft hole according to preset electric parameters. In the rounding process, a second electrode is configured on the electric spark machining device, and the electric spark machining device controls the second electrode to perform rounding treatment on the key groove according to preset electric parameters. The preset electric parameters include a preset pulse width, a preset average current, a preset pulse interval and a preset amplitude voltage.

An information handling system includes first and second USB-C channels and a baseboard management controller (BMC). The first USB-C channel receives power from a first power adaptor, and the second USB-C channel receives power from a second power adaptor. The BMC determines an average current delivered to the information handling system from the first power adaptor and the second power adaptor, allocates a first portion of the average current to the first power adaptor and a second portion of the average current to the second power adaptor, and directs the first power adaptor to provide the first portion of the average current and the second power adaptor to provide the second portion of the average current.

This application discloses a current sampling circuit, a power management chip, and an electronic device. The current sampling circuit is used to detect the average current of two alternately conducting low-side power transistors. It includes a displacement switch, a first operational amplifier circuit, and a current sensing transistor. The non-inverting input of the first operational amplifier circuit is alternately connected to the sources of the two low-side power transistors through the displacement switch. The inverting input of the first operational amplifier circuit is connected to the current sensing transistor. The output of the first operational amplifier circuit is connected to the output of the current sampling circuit. The current sensing transistor is also connected to the output of the current sampling circuit and ground, respectively. The current sensing transistor and the low-side power transistors are of the same type, and their on-resistances are proportional. This current sampling circuit can perform non-destructive testing of the low-side power transistors of a power management chip.

The invention discloses a neutral-point voltage balance control method for a three-level back-to-back frequency converter based on zero-sequence voltage injection, and belongs to the technical field of power electronics. The neutral-point voltage balance control method comprises the following steps: acquiring input three-phase voltage and current of a rectifier, output three-phase voltage and current of an inverter and voltage instantaneous values of two capacitors of a direct-current bus through voltage and current Hall components; the signals are input into the DSP after being subjected to conditioning circuit and A / D conversion; the DSP processor obtains a midpoint average current needing to be compensated by calculating a positive and negative bus capacitor voltage difference, and determines a rectification side midpoint average current reference value by combining the inversion side midpoint average current; based on the characteristic that zero-sequence voltage of a three-phase three-wire system does not affect line voltage, key zero-sequence voltage is selected within a limited range by establishing the relation between midpoint average current and the zero-sequence voltage on the rectification side, and PWM modulation waves are adjusted to achieve midpoint voltage balance. The method is simple in calculation, high in real-time performance and suitable for all modulation degree scenes.