370 results about "Total current" patented technology

The invention relates to the technical field of current compensation, and discloses a current compensation strategy and a compensation system for improving the direct current fast charging rate of an electric automobile. According to the scheme, the total current of a high-voltage loop and the input current of a battery are detected in real time, the dynamic load current difference value is calculated, and the battery health state and historical charging data are combined; and the charging pile request current value is adaptively adjusted to counteract the shunting influence of the load power. Meanwhile, a closed-loop feedback regulation mechanism is adopted, a compensation coefficient is corrected in real time through a PID algorithm, and the stability of the charging current is ensured. When the power of the charging pile is limited, the system dynamically reduces unnecessary loads (such as an air conditioner and a heater) according to a preset priority request, and the charging power of the battery is guaranteed preferentially. The charging rate is improved (the charging time is shortened by 10%-15%), the adaptability of the system to dynamic load fluctuation is enhanced, and the service life of the battery is prolonged.

The invention provides a method and a system for measuring plasma current in a quasi-ring symmetrical star simulator, and relates to the technical field of star simulators, and the method comprises the steps: determining a sensor design index according to a bootstrap current simulation calculation result, and converting the design index into an actual arrangement scheme according to an installation environment constraint; all the magnet coils are independently excited in a plasma-free state, wall eddy current interference signals generated by the magnet coils are calibrated, and thus wall eddy current calibration voltage signals are output; a sensor in an actual arrangement scheme is used for synchronously collecting a total original induced voltage signal including plasma current and wall eddy current; an integral voltage signal representing the total current is output; and compensating the integral voltage signal by using the wall eddy current calibration voltage signal, and inverting the final measurement value of the plasma current in the quasi-ring symmetric star simulator. The device and the method have the beneficial effects that the interference of a stray field on a measurement result is weakened, and a high-precision diagnostic tool is provided for the plasma physical research of the star simulator.

The invention relates to the technical field of converter power averaging and circulating current suppression, in particular to a power averaging and circulating current suppression method for parallel operation of a plurality of grid-forming type energy storage converters, which averages power through communication interaction and generates frequency and voltage compensation quantity by adopting a first regulator and a second regulator to realize accurate power averaging; meanwhile, the total current is measured locally, and virtual impedance feedforward control is adopted, so that rapid suppression of the high-frequency circulating current is realized. According to the invention, high-precision active power and reactive power equalization is realized, the capacity utilization rate is improved, high-frequency circulating current is effectively suppressed, loss and thermal stress are reduced, dynamic performance and system reliability are considered, a cooperative control architecture with complementary advantages is formed, adaptability to complex working conditions and system stability are enhanced, and engineering applicability is improved.

The invention relates to a coordination method and device for harmonic suppression and reactive power compensation in a power distribution network. The method comprises the steps of obtaining power grid operation parameter information of a power distribution network; according to the power grid operation parameter information, the total current harmonic distortion rate, the power factor and each harmonic current information of the power distribution network are detected; detecting to-be-optimized parameters of the power distribution network according to the total current harmonic distortion rate, the power factor and the current information of each harmonic, the to-be-optimized parameters including at least one of each harmonic and reactive power; and according to the to-be-optimized parameters, suppressing each harmonic in the power distribution network and compensating reactive power in the power distribution network. The method can accurately perform cooperative control on harmonic suppression and reactive power compensation in the power distribution network.

The invention discloses a motor control method and device, electronic equipment and a storage medium. The method comprises the following steps: acquiring a three-phase current, converting the three-phase current into a total current of a current period in a static coordinate system, and extracting a high-frequency current of the current period from the total current; extracting a rotor position and a rotor rotating speed from the high-frequency current; compensating the rotor rotating speed by using the expected rotating speed to obtain a quadrature-axis expected current; converting the total current into a quadrature-direct axis coordinate system, extracting a fundamental frequency current from the quadrature-direct axis coordinate system, compensating the fundamental frequency current by using a quadrature axis expected current and a direct axis bias current to obtain a first expected voltage, superposing the first expected voltage and a direct axis high-frequency voltage, and performing coordinate system conversion on a superposition result by using a rotor position to obtain a second expected voltage; obtaining a second expected voltage under the static coordinate system; and the three-phase current of the current period is controlled according to the second expected voltage to drive the motor, so that the motor has more obvious salient polarity through the direct-axis bias current, and vector control over the electrode is achieved.

The invention discloses a wide temperature range compensation method for resistive current of a lightning arrester, which belongs to the technical field of online monitoring of power equipment, and comprises the following steps: acquiring waveform data under a reference low-temperature working condition, and establishing an initial capacitive harmonic base; acquiring working condition data at any temperature in real time, performing harmonic decomposition, and analyzing to generate a nonlinear distortion feature vector; dynamically correcting the initial base by using the feature vector, and carrying out subtraction operation on the total current harmonic wave to obtain a final resistive current harmonic wave vector; and reconstructing an instantaneous resistive current waveform through inverse transformation and calculating a characteristic value. According to the technical scheme, the initial capacitive harmonic wave base is established, the nonlinear distortion feature vector is generated based on the harmonic distortion of the real-time working condition quantification temperature and valve plate nonlinear coupling, and dynamic feedback correction is conducted on the base, so that the real resistive current waveform in the wide temperature range can be accurately separated and reconstructed, and the accuracy of the real resistive current waveform in the wide temperature range is improved. And the accuracy and reliability of lightning arrester state evaluation are improved.

The invention belongs to the field of electrical variable measurement, and particularly relates to a single battery equalization management method for a lithium battery BMS (Battery Management System) protection board, which comprises the following steps of: acquiring voltage, temperature, total current and cycle index of each single battery in real time; based on a second-order equivalent circuit model and an extended Kalman filtering algorithm, multi-source information is fused, and the health state and the charge state are estimated with high precision; constructing a dynamic equilibrium trigger threshold fusing the charge state standard deviation, the range and the health state attenuation factor; a bidirectional flyback or multi-winding transformer active equalization strategy is selected according to the inconsistent distribution characteristics and the temperature field, and equalization current is accurately controlled through pulse width modulation; and continuously monitoring the efficiency, the temperature rise rate and the convergence in the equalization process, and dynamically optimizing the equalization parameters by using the fuzzy logic controller until the inconsistency reaches the standard. According to the technical scheme, accurate, self-adaptive, high-efficiency and safe single battery equalization management can be realized, the service life of the battery pack is effectively prolonged, and the operation reliability of the system is improved.

The invention belongs to the technical field of quality detection, and discloses an electrical automation quality detection method and system. The method comprises the steps of collecting original voltage and current signals of a PCC point of a power grid and performing FFT to obtain a background harmonic frequency set and a background harmonic amplitude set; generating an initial frequency grid based on a preset target frequency band, and generating a sparse frequency grid in combination with the background harmonic waves; calculating the estimated signal-to-noise ratio of each candidate frequency, performing ascending sorting to obtain an injection sequence, injecting sinusoidal signals, collecting PCC point voltage response and total current, and calculating a frequency impedance data pair; performing rational function fitting based on the frequency impedance data to obtain a broadband impedance curve; analyzing the curve, extracting quality characteristic parameters, and performing quality judgment according to the parameters; according to the method, the technical problem that the grid-connected stability quality of a single new energy converter cannot be quickly and automatically qualified in a production line offline detection scene in the prior art is effectively solved.

The invention discloses a charging and discharging control method, control system and equipment for a two-way battery energy storage inverter, and the method comprises the steps: detecting a DC bus voltage, comparing the DC bus voltage with a target value, and generating a bus voltage error signal; inputting the error signal into a voltage outer loop controller, and outputting a total current given value of the system; acquiring a first path of battery charge state value and a second path of battery charge state value in real time; a current distribution strategy is dynamically selected; when the state-of-charge values are all higher than or lower than the target SOC, a proportional distribution strategy is executed; when the SOC value of one path is larger than the target SOC and the SOC value of the other path is smaller than the target SOC, a forced equalization strategy is executed; and distributing a current given value into independent current to be input into a corresponding current inner ring, and generating a PWM signal for driving a switch tube so as to realize that proportional distribution is adopted for a same-direction state to avoid overload and forced equalization is adopted for a reverse state to realize energy transfer, thereby prolonging the service life of a battery.

The invention provides a current sharing method for multiple power supply racks, which can be applied to the technical field of server power supply current sharing. The current sharing method comprises the following steps: a master controller detects the number of first current power supply units in a plurality of first power supply units and a first total current output quantity, receives the number of second current power supply units in a plurality of second power supply units from a slave controller and a second total current output quantity, and determines a current mean value, a current-sharing signal including a current average value is synchronously issued to the master controller and the plurality of slave controllers; the main processor detects a heartbeat signal of the main controller, controls the first switch module to disconnect the electric connection between the main controller and the plurality of first power supply units and controls the second switch module to disconnect the electric connection between the main controller and the fourth switch module under the condition that the heartbeat signal is not detected within a preset time period; and the second switch module is electrically connected with the plurality of first power supply units and the fourth switch module so as to realize the function of the main controller.

The invention discloses a battery monomer self-adaptive equalization method in a new energy automobile charging process, and aims to solve the problems of lagging, stiffness and poor coordination with a charging process of an existing equalization technology. The method comprises the following steps: collecting total voltage and total current of a battery pack and voltage and temperature of each monomer in real time; calculating a single voltage dispersion index and comparing the single voltage dispersion index with a threshold value to judge an equalization starting opportunity; dynamically calculating an adaptive equalization threshold based on the average state of charge, the average temperature and the aging degree of the battery pack; classifying each monomer according to the threshold value, and constructing a balanced target recognition matrix; and finally, in combination with the current charging stage, executing a layered equalization decision, and controlling the charging equipment and the active equalization circuit to work cooperatively. According to the method, deep coordination of equalization and charging is realized, the charging speed, the energy utilization rate and the charging saturation of the battery pack are remarkably improved through a dynamic threshold value and a hierarchical control strategy, and the overall service life of the battery pack is effectively prolonged.

The invention, which relates to the technical field of low-voltage apparatus detection, discloses an intelligent detection circuit for the working state of a low-voltage apparatus, comprising a low-voltage apparatus module for controlling the transmission state of electric energy and controlling the low-voltage apparatus module to transfer and consume the electric energy in cooperation with a driving module when the power is ready to be cut off. The current detection module performs total current detection, the transfer detection module performs current detection on transferred energy, and a detected signal is processed by the transfer degree detection module and judges whether an electric energy transfer requirement during power failure is met or not; the voltage drop detection module is triggered to carry out saturation conduction voltage drop detection on the low-voltage equipment module, whether aging occurs or not is judged, and when aging does not occur, the driving module is controlled to adjust the driving voltage and the electric energy transfer degree. The intelligent detection circuit for the working state of the low-voltage electric appliance can effectively detect whether the low-voltage electric appliance has an electric energy transfer problem, automatically adjust the electric energy transfer degree and improve the safety of the circuit.

A method for protecting a battery of an electronic device including a plurality of batteries, includes: measuring a total current (Itotal) value output from a charging module while the plurality of batteries are charged via the charging module; detecting a first current (I1) value output to a first battery via a current limiter; calculating a difference between the total current (Itotal) value and the first current (I1) value to estimate a second current (I2) value transferred to a second battery without passing through any current limiter, where the first battery and the second battery are included in the plurality of batteries; and controlling, based on the estimated second current (I2) value, a current of the second battery, which has the second current (I2) value, by controlling opening / closing of a switching module included in a protection circuit module of the second battery.

The invention provides an online detection system and method for electrochemical alternating-current impedance of a fuel cell, and aims to solve the problems of limited measurement frequency range and insufficient control precision caused by bandwidth limitation of a controller in the existing EIS online detection technology, and the online detection system comprises a fuel cell and a power supply system of a DC-DC converter, the disturbance signal generation module generates a sine disturbance current signal; the feedforward and feedback control module takes the total current reference signal as a control target, and calculates to obtain a final adjustment duty ratio for driving the DC-DC converter; when the DC-DC converter is driven by the final adjustment duty ratio, a data acquisition module synchronously acquires an input voltage and an input current which are input into the DC-DC converter as a response voltage signal and a response current signal; and the impedance demodulation module is used for demodulating and calculating the electrochemical alternating current impedance of the fuel cell based on the frequency of the response voltage signal, the response current signal and the sine disturbance current signal.

The invention provides a bypass switch switching control method suitable for the charging and discharging process of a series battery pack system, and the method comprises the steps: obtaining the voltage and current information of each battery unit, and judging the charging and discharging states of the battery units; for a battery unit in a charging or discharging state, if the voltage of the battery unit reaches a preset charging cut-off voltage, a switch A connected in series with the battery unit is controlled to be switched off step by step, and meanwhile, a switch B connected in parallel with the battery unit is controlled to be switched on step by step, so that bypass of the battery unit is realized; in the process of controlling the switching of the switch A and the switch B, the on-resistance of the switch A and the switch B is adjusted, so that the current flowing through the switch-off switch is gradually reduced to zero, the current flowing through the switch-on switch is gradually increased, the total current of the switch A and the switch B is kept constant, the total current is the charging current of the system, and the soft switching of the bypass switch is realized; the charging and discharging process of the battery pack is kept continuous, so that the working stability of the whole system is realized.

The invention discloses a programmable low-temperature-drift under-voltage locking circuit, and the circuit comprises a reference current generation module which is used for outputting an initial reference current, and the input end of the reference current generation module is connected with a first reference voltage; the zero-temperature-drift current source array is used for generating reference current according to the initial reference current and the second reference voltage and mirroring the reference current to a plurality of parallel branches; the trimming module is used for adjusting the total current of the parallel branches by using a programmable resistor and a capacitor; the sampling module is used for sampling the total current and the power supply voltage of the parallel branches output by the trimming module; and the comparison output module is used for comparing the power supply voltage with a sampling voltage generated according to the programmable resistor and the total current of the parallel branches, and outputting a pair of differential signals. Through the reference current generation module, the zero-temperature-drift current source array, the trimming module, the sampling network and the voltage comparator, the problems that in an existing resistance voltage division type undervoltage locking scheme, a threshold value is fixed and cannot be adjusted, and the scheme is sensitive to temperature changes are solved.

A switch shut-off device is applied to a power supply system equipped with a first power source and a second power source connected via an electrical pathway, and a plurality of switches provided in the electrical pathway and connected in series with each other. The switch shut-off device includes a calculation unit configured to acquire an energization current flowing through each of a pair of switches that are adjacent to each other in the electrical pathway, among the plurality of switches, and to calculate a total current that is a sum of the energization currents flowing to an intermediate point between the pair of switches, and a shut-off unit configured to shut off the pair of switches when the total current exceeds a threshold current.

The invention belongs to the technical field of electronic information, and relates to an online low-voltage load monitoring and abnormal tripping positioning method and a related device. According to the method, electrical parameters of all monitoring points are collected in real time, key parameters are calculated after analog-to-digital conversion and filtering denoising, and the key parameters are compared with a set threshold value to judge whether the monitoring points are in an abnormal state or not; once an abnormal state is found, an early warning is generated and uploaded to a remote platform; and continuously monitoring the state of the main switch or the total current at the same time, and when tripping occurs, backtracking an abnormal record within a preset time period before tripping, and positioning the last or the most serious abnormal monitoring point as an abnormal source. The system comprises a data acquisition module, an analog-to-digital conversion module, a preprocessing module, a calculation module, a judgment module, an early warning module, a trip monitoring module and a positioning module. According to the invention, early warning before a fault and rapid positioning after tripping are realized, and the intelligent level, the operation and maintenance efficiency and the power supply reliability of the power distribution network are improved.

The invention provides a distributed photovoltaic grid-connected converter low-voltage ride-through control method based on sum-difference coordinate transformation, and solves the problems of insufficient synchronism, poor stability, insufficient reactive power support potential excavation and the like existing in collaborative response under power grid voltage drop during distributed photovoltaic grid connection. According to the method, impedance modeling and equivalent symmetry transformation are carried out on the distributed photovoltaic inverter, and a coupling multi-dimensional matrix equation is established; an original coupling system is decoupled into a sum current channel and a plurality of difference current channels, the control complexity is simplified, and an open-loop output impedance expression and a closed-loop output impedance expression are deduced; secondly, formulating a refined active / reactive current collaborative distribution strategy for different voltage drop depths, dynamically calculating the minimum reactive current during voltage drop, preferentially meeting the national standard, and maximizing active output or balancing loss under the limit of rated current; and finally, through sum-difference coordinate transformation, the total current demand and distribution are efficiently decoupled and issued to a current loop controller of each inverter, so that rapid, synchronous and stable cooperative operation of multiple inverters is realized.

The invention relates to a power supply circuit with a monitoring function comprising a first current branch (2) with a first controllable section (20) and at least one load (21) arranged in series therewith, and a second current branch (3) with a second controllable section (30) and at least one load (31) arranged in series therewith. A controllable converter (4) is connected to the first and second current branches (2, 3) to supply a total current. A control circuit (5) with a control input, which is connected to the set input (10), wherein the control circuit (5) is coupled to the first controllable section (20) to adjust a current through the first current branch (2) depending on a provided first set signal.The second controllable branch (30) is coupled to the first current branch (2) and to the set input (10) in a dependent control loop, which is influenced by the current flowing in the first circuit (2) and the forward voltage of the two loads (21 and 31). It is configured to control a current through the second current branch (3) depending on an operating state through the first current branch (2) and a second set signal. Furthermore, a current-controlled monitoring circuit is provided, which is connected to a node between the respective current branch and the load connected in series with it. This circuit is configured to generate an error signal in response to a predefined deviation of one of the currents flowing into the current-controlled monitoring circuit, which reflects the state of the respective load.

The invention discloses a three-phase four-wire converter, a power supply system and a voltage control method, and a control unit responds to the condition that the instantaneous voltage of a capacitor midpoint is greater than a second voltage threshold value, and controls a balance bridge arm, so that the current part flowing into an inductor is greater than the current part flowing into a second bus capacitor in the total current flowing into the capacitor midpoint. And the control unit further controls the balance bridge arm according to the voltage peak-to-peak value of the capacitor midpoint and the first voltage threshold in response to the situation that the instantaneous voltage of the capacitor midpoint is not greater than the second voltage threshold, so that the total current flowing into the capacitor midpoint is distributed in the current part flowing into the second bus capacitor and the current part flowing into the inductor. According to the arrangement, the magnitude of the first bus capacitor and the magnitude of the second bus capacitor do not need to be increased additionally, the balance bridge arm is controlled, and the distribution proportion of the total current distributed in the current part flowing into the second bus capacitor and the current part flowing into the inductor is adjusted, so that the output voltage waveform and the system loss are taken into consideration.

The invention discloses a charging and discharging control method, energy storage equipment and a storage medium, and is applied to the technical field of energy control. The charging and discharging control method is applied to the energy storage equipment, the energy storage equipment comprises a main battery pack and at least one power-up pack which are connected in parallel, the charging and discharging control method comprises the steps that the charging current and the discharging current of the energy storage equipment are obtained, the charging current is the sum of the charging current of the main battery pack and the charging current of each power-up pack, and the discharging current is the sum of the charging current of each power-up pack; the discharge current comprises the sum of the discharge current of the main battery pack and the discharge current of each power-up pack; under the condition that the energy storage equipment is charged and discharged at the same time, total current is determined based on the charging current and the discharging current; determining a first charging and discharging mode based on the total current; and switching the current working mode of the energy storage equipment into the first charging and discharging mode. The working mode is determined through the charging current and the discharging current, the response speed can be increased, and the hardware cost is reduced.

The invention relates to the technical field of power electronic application, in particular to a negative-sequence voltage compensation control method of a network-forming STATCOM (Static Synchronous Compensator). Comprising the steps of bridge arm current reference instruction unit phasor calculation, reactive voltage control, bridge arm positive sequence and negative sequence reactive current instruction calculation, bridge arm current reference instruction amplitude limiting logic, zero sequence voltage injection control and modulation wave instruction calculation. According to the method, the negative-sequence current output by the networking STATCOM in the asymmetric transient fault is always inductive, the proportion coefficient of the amplitude of the negative-sequence current instruction can be adjusted according to the requirements of an engineering project, and the cost is reduced; by dynamically solving a quadratic equation of unary of a reactive current amplitude limiting coefficient, an active current instruction is not limited by amplitude, balance control of direct current voltage is preferentially ensured, the reactive current is reasonably limited in amplitude, a total current reference instruction value is always in a maximum design value range of short-time overcurrent, and the stability and the safety of the device are improved.

The invention discloses a method for supporting high-frequency AC / DC component acquisition in core grounding current monitoring, which belongs to the technical field of transformers and comprises the steps of system initialization and communication establishment, continuous sample acquisition, period preprocessing and frequency spectrum and DC component calculation. The technical problem of accurately collecting and analyzing the high-frequency harmonic component and the direct-current component of the grounding current of the iron core at the same time is solved, the dual-channel sampling and digital signal processing technology is combined, on the basis of calculating the total current and the power frequency component, multi-dimensional monitoring and intelligent analysis of the running state of the transformer are achieved, and the fault diagnosis accuracy of the transformer is improved. According to the invention, various industrial scenes can be covered, missing detection of potential faults is avoided, and the fault early warning capability and the operation state judgment precision are improved.

The invention relates to a current stress optimization hybrid modulation strategy of a three-phase dual-active bridge converter, which gets rid of a traditional symmetric bridge phase shift modulation strategy, provides a modulation mode of simultaneously switching on and off a b-phase switch tube and a c-phase switch tube in the three-phase dual-active bridge converter, and enables the phase a to be compared with the b-phase switch tube and the c-phase switch tube to have variable bridge internal shift. A modulation strategy of a three-phase dual active bridge converter similar to a DAB triple phase shift modulation mode is formed; meanwhile, mixed modulation is formed with single phase shift modulation of the three-phase dual-active bridge converter, total current stress serves as an optimization target, Pn is obtained through calculation of a PI controller, the voltage transformation ratio M at the moment is calculated, values of respective total current stress under the two kinds of modulation can be obtained, the total current stress under the two kinds of modulation is compared, and the optimal value of the total current stress under the three-phase dual-active bridge converter is obtained. And a modulation mode with the optimal real-time total current stress is selected, so that the total current stress of the converter is optimized under the same transmission power.

The invention provides a leakage current detection method, a power supply device and a storage medium, the leakage current detection method is applied to a scene that the power supply device is connected with at least one other measurement device besides a to-be-detected load device, and equivalent leakage impedance introduced by the at least one measurement device itself is quantified. In combination with the actual output voltage of the power supply device in the current scene working state, the leakage current value flowing through the measuring device is accurately calculated so as to compensate the current between the power supply device and the load device. Compared with the traditional scheme, the detection method actively measures and quantifies the current interference caused by the equivalent leakage impedance of the measurement equipment, and further compensates the leakage component in the total current measurement value supplied to the load by the power supply, thereby realizing the accurate reduction of the real current of the load, and improving the overall precision and reliability of the current measurement; meanwhile, the detection and compensation mechanism does not depend on complex hardware isolation and has the advantages of being low in implementation cost and high in adaptability.

The invention discloses a seamless range switching system and a seamless range switching method for instrument current measurement. The seamless range switching system comprises a digital-to-analog converter, an error amplifier, a first driving circuit, a first current measurement circuit, a clamping circuit, a second driving circuit, a second current measurement circuit, two analog-to-digital converters and a field programmable gate array. The first current measuring circuit converts 10 [mu] A to 30 mA low current into a first voltage signal to form a negative feedback closed loop. When the first voltage signal reaches a Zener breakdown threshold value, the clamping circuit outputs a trigger signal to start the second driving circuit, so that the two driving circuits jointly provide a total current of 30mA to 500mA for the load; the two analog-to-digital converters perform synchronous sampling, and the field programmable gate array selects digital signal output which is in a linear measurement range and has an error not exceeding + / -0.05% of a full scale. No mechanical switch exists in the switching process, the current is uninterrupted, and wide-range high-precision continuous measurement is achieved.

The application discloses a superconducting synchronous phase modifier excitation power supply device, which comprises a three-phase rectifying device, an adjusting module, a protection module and a digital control module, wherein the three-phase rectifying device is used for providing a bus side DC voltage; the adjusting module is used for adjusting an excitation total current; the protection module is used for ensuring safe operation of the device; and the digital control module is used for realizing high-precision continuous adjustment of excitation winding voltage and current. The superconducting synchronous phase modifier excitation power supply device solves the problem of unbalanced reactive output of the superconducting synchronous phase modifier caused by large excitation current ripple, and improves the reliability of the superconducting synchronous phase modifier.

The invention discloses a temperature control method and device for a laser and a medium, and relates to the technical field of temperature control, and the method comprises the steps: obtaining the operation parameters of a pump source assembly in a laser system, and carrying out the data query and interpolation calculation through a predefined current heat mapping table based on the pump source current in the operation parameters, and generating a thermal load prediction value; based on the thermal load predicted value and according to the working mode of the laser, a refrigeration control signal is generated, and the refrigeration control signal is sent to an execution component of the refrigeration system so as to control at least one of the rotating speed of a compressor, the opening degree of an expansion valve and the rotating speed of a fan; and calculating a current fine tuning coefficient according to the difference between a target temperature value in the thermal load predicted value and an actual temperature value, performing overall current compensation according to the difference between a power set value in the thermal load predicted value and an actual power value, and outputting an independent current adjustment value and a total current adjustment value of each pump source assembly.

A circuit arrangement comprises a setting input (10) for supplying a setting signal, a first current branch (2) with a first controllable path (20) and at least one optoelectronic component (21) arranged in series therewith, and a second current branch (3) with a second controllable path (30) and at least one optoelectronic component (31) arranged in series therewith. A controllable, current-regulated converter (4) is connected to both current branches (2, 3) for supplying a total current. Furthermore, a control circuit (5) is provided with a setting input which is connected to the setting input (10), wherein the control circuit (5) is coupled to the first controllable path (20) for setting a current through the first current branch (2) as a function of the setting input (10).The second controllable path (3) is coupled to the first current branch (2) and to the setting input (10) to form a control loop and is designed to control a current through the second current branch (3) as a function of an operating state through the first current branch (2) and the setting signal.