Intelligent temperature compensation device for high-precision high-power converters

Abstract

The present invention discloses an intelligent temperature compensation device for high-precision high-power converters, comprising: multiple temperature sampling units, precision and stability control units, curve loading units and digital PWM adjustment units that are electrically connected in sequence. The device can reduce the temperature coefficient index of the high-precision high-power converter when working at an extreme ambient temperature to a level less than 20ppm, thereby greatly improving the output voltage and current accuracy; it can automatically adjust the control loop parameters according to the corresponding relationship between the measured temperature and the distribution parameters, greatly improving the output stability under high and low temperature environments; it has an automatic calibration function for the temperature drift curve, realizes active communication with a remotely connected programmable voltmeter, programmable ammeter, programmable electronic load, and environmental test box, and automatically performs calibration and curve drawing; all compensation methods and processes are automated and intelligent, and can be unattended.

Description

Technical Field

[0001] The invention relates to the fields of AC / DC power supplies, electronic loads and high-power converter equipment, and in particular to an intelligent temperature compensation device for high-precision high-power converters. Background Art

[0002] In the fields of industrial equipment, information communication, measurement and control, various high-precision AC and DC stable power supplies and electronic loads are used in equipment development, maintenance and measurement testing. In recent years, with the continuous improvement of industrial technology, a variety of comprehensive requirements have been put forward for power supplies, and environmental adaptability is one of the key indicators.

[0003] High-precision AC / DC stable power supplies are widely used; among them, the kilowatt-level high-performance series products are tested at an ambient temperature of 23℃±5℃, and the output voltage programming and measurement accuracy can reach about 0.3‰, and the output current programming and measurement accuracy can reach about 1‰, which can meet most application occasions. At present, the main problems of this type of power supply are: 1) The operating temperature range in the environmental adaptability requirements is wide, mostly -40~+60℃. Even if calculated according to the 100ppm temperature drift coefficient required by high-performance power supplies, when the power supply works in high and low temperature environments, the output voltage and current accuracy will drop to 5‰, which is several times or even more than ten times the difference compared with normal temperature. 2) Most of the key component parameters change with the ambient temperature, which will degrade the output indicators and even cause oscillation, affecting reliability. The huge output difference of high-precision power converters under normal temperature and high and low temperature environments will seriously affect the application of precision equipment in complex environments; therefore, how to solve the above problems is an urgent problem to be solved in the fields of AC / DC power supplies, electronic loads, high-power converters and testing. Summary of the invention

[0004] Based on the problems existing in the prior art, the purpose of the present invention is to provide an intelligent temperature compensation device for high-precision high-power converters, which can solve the problem that the accuracy of output voltage and current of AC and DC power supplies, electronic loads and high-power converters is reduced due to changes in ambient temperature, thereby affecting reliability.

[0005] The objective of the present invention is achieved through the following technical solutions:

[0006] The embodiment of the present invention provides an intelligent temperature compensation device for a high-precision high-power converter, comprising:

[0007] Multiple temperature sampling units, precision and stability control units, curve loading units and digital PWM adjustment units; among them,

[0008] The multiple temperature sampling unit is provided with multiple groups of temperature sampling devices for connecting to the high-precision high-power converter, which can respectively obtain the temperature signals of different circuit parts of the high-precision high-power converter, and respectively normalize the obtained temperature signals of different circuit parts of the high-precision high-power converter to form a rough temperature signal output;

[0009] The precision and stability control unit is electrically connected to the multiple temperature sampling unit and the curve loading unit, respectively, and can perform signal distribution processing and differentiation processing on the rough temperature signals corresponding to different circuit parts output by the multiple temperature sampling unit, and obtain the temperature signals corresponding to the current, internal environment, voltage, power switch device, magnetic element and second-order filter circuit respectively, and form a current temperature drift characteristic curve and a voltage temperature drift characteristic curve according to the temperature signals corresponding to the current and voltage respectively and the temperature signal corresponding to the internal environment; form a distributed parameter temperature drift characteristic curve according to the temperature signals corresponding to the power switch device, magnetic element and second-order filter circuit;

[0010] The curve loading unit is electrically connected to the precision and stability control unit and the digital PWM adjustment unit, respectively, and can load the current temperature drift characteristic curve and the voltage temperature drift characteristic curve output by the precision and stability control unit and the distributed parameter temperature drift characteristic curve output by the precision and stability control unit to the digital PWM adjustment unit after calibrating them;

[0011] The digital PWM adjustment unit is electrically connected to the curve loading unit and the high-precision high-power converter, respectively, and can form a PWM adjustment signal according to the current temperature drift characteristic curve, the voltage temperature drift characteristic curve and the distributed parameter temperature drift characteristic curve output by the curve loading unit, and control the high-precision high-power converter through the PWM adjustment signal.

[0012] It can be seen from the technical solution provided by the present invention that the intelligent temperature compensation device for high-precision high-power converter provided by the embodiment of the present invention has the following beneficial effects:

[0013] By setting up multiple temperature sampling units, precision and stability control units, curve loading units and digital PWM adjustment units connected in sequence, effective temperature measurement can be implemented on multiple important parts or components of high-precision high-power converters. By comprehensive data processing of multiple measurement points, combined with automatically loaded and calibrated temperature drift and distributed parameter curves, the compensation reference input voltage and the PWM signal of the power switch can be effectively adjusted and controlled, and finally the high-precision high-power converter can achieve a temperature coefficient index of less than 20ppm when working at extreme ambient temperatures, greatly improving the output voltage and current accuracy; the compensation device automatically adjusts the control loop parameters according to the corresponding relationship between the measured temperature and the distributed parameters, thereby greatly improving the output stability under high and low temperature environments; the compensation device can be automatically implemented by hardware circuits and software control algorithms, without manual settings and adjustments, and can realize intelligent temperature compensation. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0015] Figure 1 A schematic diagram of the structure of an intelligent temperature compensation device provided by an embodiment of the present invention;

[0016] Figure 2 A schematic diagram of a process for crimping the temperature sensor in the multiple temperature sampling unit provided by an embodiment of the present invention with the output current precision sampling resistor and the power switch device respectively;

[0017] Figure 3 A schematic diagram of a flexible circuit application structure in a multiple temperature sampling unit provided in an embodiment of the present invention;

[0018] Figure 4 A schematic diagram of a sampling circuit in a multiple temperature sampling unit provided in an embodiment of the present invention;

[0019] Figure 5 A schematic diagram of an input signal distribution circuit in a precision and stability control unit provided in an embodiment of the present invention;

[0020] Figure 6 An oscilloscope interface diagram of input signal distribution waveform in the accuracy and stability control unit provided in an embodiment of the present invention;

[0021] Figure 7 A schematic diagram of a temperature drift curve of a σR / R precision sampling resistor for output current provided in an embodiment of the present invention;

[0022] The components corresponding to the marks in the figure are: 1-multiple temperature sampling unit; 11-precision current feedback module; 12-internal environment temperature feedback module; 13-output voltage feedback module; 14-power switch temperature module; 15-magnetic element temperature module; 16-second-order filter temperature module; 2-accuracy and stability control unit; 21-output current accuracy control module; 22-internal environment temperature control module; 23-output voltage accuracy control module; 24-stability control module; 3-curve loading unit; 31-temperature drift curve calibration module; 32-temperature drift curve loading module; 33-distributed parameter curve loading module; 4-digital PWM adjustment unit; 5-high-precision high-power converter; A-temperature sensor; B-bottom buried point of temperature sensor; C-heat sink;. DETAILED DESCRIPTION

[0023] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in combination with the specific content of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the protection scope of the present invention. The contents not described in detail in the embodiments of the present invention belong to the prior art known to professional and technical personnel in this field.

[0024] like Figure 1 As shown, an embodiment of the present invention provides an intelligent temperature compensation device for a high-precision high-power converter, which can measure and control the high-precision high-power converter as a whole to achieve temperature compensation, including:

[0025] Multiple temperature sampling units, precision and stability control units, curve loading units and digital PWM adjustment units; among them,

[0026] The multiple temperature sampling unit is provided with multiple groups of temperature sampling devices for connecting to the high-precision high-power converter, which can respectively obtain the temperature signals of different circuit parts of the high-precision high-power converter, and respectively normalize the obtained temperature signals of different circuit parts of the high-precision high-power converter to form a rough temperature signal output;

[0027] The precision and stability control unit is electrically connected to the multiple temperature sampling unit and the curve loading unit, respectively, and can perform signal distribution processing and differentiation processing on the rough temperature signals corresponding to different circuit parts output by the multiple temperature sampling unit, and obtain the temperature signals corresponding to the current, internal environment, voltage, power switch device, magnetic element and second-order filter circuit respectively, and form a current temperature drift characteristic curve and a voltage temperature drift characteristic curve according to the temperature signals corresponding to the current and voltage respectively and the temperature signal corresponding to the internal environment; form a distributed parameter temperature drift characteristic curve according to the temperature signals corresponding to the power switch device, magnetic element and second-order filter circuit;

[0028] The curve loading unit is electrically connected to the precision and stability control unit and the digital PWM adjustment unit, respectively, and can load the current temperature drift characteristic curve and the voltage temperature drift characteristic curve output by the precision and stability control unit and the distributed parameter temperature drift characteristic curve output by the precision and stability control unit to the digital PWM adjustment unit after calibrating them;

[0029] The digital PWM adjustment unit is electrically connected to the curve loading unit and the high-precision high-power converter, respectively, and can form a PWM adjustment signal according to the current temperature drift characteristic curve, the voltage temperature drift characteristic curve and the distributed parameter temperature drift characteristic curve output by the curve loading unit, and control the high-precision high-power converter through the PWM adjustment signal.

[0030] In the above-mentioned temperature compensation device, the multiple temperature sampling unit comprises:

[0031] Precision current feedback module, internal environment temperature feedback module, output voltage feedback module, power switch temperature module, magnetic component temperature module and second-order filter temperature module; among them,

[0032] The precision current feedback module, the internal environment temperature feedback module, the output voltage feedback module, the power switch temperature module, the magnetic element temperature module and the second-order filter temperature module are each provided with a set of temperature sampling devices;

[0033] The temperature sampling devices of the precision current feedback module, the internal environment temperature feedback module, the output voltage feedback module, the power switch temperature module, the magnetic element temperature module and the second-order filter temperature module are respectively connected to the output current precision sampling resistor, the loop control circuit, the output voltage feedback circuit, the power switch device, the magnetic element and the second-order filter circuit of the high-precision high-power converter, and can respectively collect the temperature signals of the output current precision sampling resistor, the loop control circuit, the output voltage feedback circuit, the power switch device, the magnetic element and the second-order filter circuit.

[0034] In the above-mentioned temperature compensation device, the precision current feedback module, the internal environment temperature feedback module, the output voltage feedback module, the power switch temperature module, the magnetic element temperature module and the second-order filter temperature module all adopt a temperature sampling circuit.

[0035] In the above-mentioned temperature compensation device, the temperature sampling device of the precision current feedback module adopts a temperature sensor, and the temperature sensor is connected to the aluminum-based heat sink connected to the output current precision sampling resistor by pressing the heat sink nearby or burying the heat sink;

[0036] The temperature sampling device of the power switch temperature module adopts a temperature sensor, and the temperature sensor is connected to the aluminum-based heat sink connected to the power switch device by pressing the heat sink nearby or burying the heat sink;

[0037] The temperature sampling device of the internal environment temperature feedback module adopts two temperature sensors, wherein one temperature sensor is arranged on the surface of the printed circuit board of the loop control circuit, and the other temperature sensor is arranged in the space around the printed circuit board of the loop control circuit; the two temperature sensors respectively measure the surface temperature of the printed circuit board at the measured part and the ambient temperature of the space around the circuit, and finally convert the influence factor by the weight of each circuit; in actual application, according to the different structures of the high-precision high-power converter, multiple temperature sensors can be arranged respectively (such as multiple places on the surface of the circuit board, multiple places in the chassis), and the temperatures of multiple environments can be measured at the same time (a single internal environment temperature is obtained by averaging, comparing or weighting) to obtain a more accurate internal environment temperature.

[0038] The temperature sampling device of the output voltage feedback module adopts two temperature sensors, wherein one temperature sensor is arranged on the surface of the printed circuit board of the output voltage feedback circuit, and the other temperature sensor is arranged in the space around the printed circuit board of the output voltage feedback circuit; the two temperature sensors respectively measure the surface temperature of the printed circuit board at the measured part and the ambient temperature of the space around the circuit, and finally convert the influence factor by the weight of each circuit;

[0039] The temperature sampling device of the power switch temperature module adopts a temperature sensor with a hollow structure at the bottom, and the temperature sensor is arranged on a flexible circuit application structure, and the flexible circuit application structure is wound around the surface of the power switch device whose temperature is to be measured;

[0040] The temperature sampling device of the magnetic element temperature module adopts a temperature sensor with a hollow structure at the bottom, and the temperature sensor is arranged on a flexible circuit application structure, and the flexible circuit application structure is wound and arranged on the surface of the magnetic element whose temperature is to be measured;

[0041] The temperature sampling device of the second-order filter temperature module adopts a temperature sensor with a hollow structure at the bottom. The temperature sensor is arranged on a flexible circuit application structure. The flexible circuit application structure is wound around the surface of the filter electrolytic capacitor of the second-order filter circuit whose temperature is to be measured.

[0042] Through this flexible circuit application structure and the temperature sensor with a hollow bottom, the surface temperature of cylindrical devices (such as electrolytic capacitors and other devices) can be measured more accurately, providing accurate parameters for subsequent temperature compensation control.

[0043] In the above-mentioned temperature compensation device, the accuracy and stability control unit includes:

[0044] Input signal distribution circuit, temperature differentiation processing module, output current accuracy control module, internal environment temperature control module, output voltage accuracy control module and stability control module; wherein,

[0045] The input signal distribution circuit is electrically connected to the multiple temperature sampling units, and is electrically connected to the output current precision control module, the internal environment temperature control module, the output voltage precision control module and the stability control module respectively through the temperature differentiation processing module, and can send each rough temperature signal output by the multiple temperature sampling units to the temperature differentiation processing module for signal distribution processing, and then distribute it to the output current precision control module, the internal environment temperature control module, the output voltage precision control module and the stability control module accordingly after size comparison and / or weight differentiation processing;

[0046] The internal environment temperature control module is electrically connected to the output current accuracy control module and the output voltage accuracy control module respectively, and can receive the temperature signal corresponding to the internal environment after the differentiation process, and output it to the output current accuracy control module and the output voltage accuracy control module respectively;

[0047] The output current precision control module can obtain the temperature signal corresponding to the current according to the temperature signals corresponding to the output current precision sampling resistor and the internal environment after the differentiation processing;

[0048] The output voltage accuracy control module can obtain a temperature signal corresponding to the voltage according to the temperature signals corresponding to the output voltage feedback circuit and the internal environment after differentiation processing;

[0049] The stability control module can obtain the temperature signal corresponding to the distributed parameter according to the temperature signals corresponding to the power switch device, magnetic element and second-order filter circuit after the difference processing. The stability control module has two functions. First, the output signal of the module provides a discrete input quantity for the temperature drift curve calibration module in the subsequent curve loading unit during the calibration link; second, it provides real-time temperature data related to the stability control function when the high-precision high-power converter is working, which is an important parameter for the high-precision high-power converter to work stably.

[0050] In the above temperature compensation device, the input signal distribution circuit includes: a high-speed analog switch multi-channel serial selection circuit, a high-precision differential operational amplifier and a differential analog-to-digital converter that are electrically connected.

[0051] In the above-mentioned temperature compensation device, the curve loading unit comprises:

[0052] Temperature drift curve calibration module, temperature drift curve loading module and distributed parameter curve loading module; wherein,

[0053] The temperature drift curve calibration module is electrically connected to the accuracy and stability control unit and the temperature drift curve loading module, and can communicate with the remotely connected programmable voltmeter, programmable ammeter, programmable electronic load, and environmental test box to automatically calibrate the current temperature drift characteristic curve and the voltage temperature drift characteristic curve received from the accuracy and stability control unit, and send the calibrated current temperature drift characteristic curve and the voltage temperature drift characteristic curve to the temperature drift curve loading module, and the characteristic quantities corresponding to the current temperature drift characteristic curve and the voltage temperature drift characteristic curve are the output current precision sampling resistance σR / R and the output voltage σU / U respectively. set ;

[0054] The temperature drift curve loading module is electrically connected to the temperature drift curve calibration module and the digital PWM adjustment unit, respectively, and can load the current temperature drift characteristic curve and the voltage temperature drift characteristic curve received from the temperature drift curve calibration module into the digital PWM adjustment unit;

[0055] The distributed parameter curve loading module is electrically connected to the precision and stability control unit and the digital PWM adjustment unit, respectively, and can load the distributed parameter temperature drift characteristic curve received from the precision and stability control unit to the digital PWM adjustment unit; the characteristic quantity corresponding to the distributed parameter temperature drift characteristic curve is the distributed parameter equivalent series resistance ESR.

[0056] In the above-mentioned temperature compensation device, the digital PWM adjustment unit can calibrate the three characteristic quantities corresponding to the current temperature drift characteristic curve, the voltage temperature drift characteristic curve and the distributed parameter temperature drift characteristic curve through the current temperature drift characteristic curve, the voltage temperature drift characteristic curve and the distributed parameter temperature drift characteristic curve corresponding to the actual temperature value of the high-precision high-power converter (the actual temperature value is the temperature value measured by the multiple temperature sampling units), and obtain the three characteristic quantities after calibration, namely, the output current precision sampling resistance value, the output voltage compensation value σU, and the distributed parameter equivalent series internal resistance ESR. The output current setting value, the output voltage setting value and the digital loop compensation parameter k are determined according to the fixed parameters and topological characteristic parameters of the high-precision high-power converter through the three calibrated characteristic quantities. p , k i , k d , and according to the obtained output current setting value, output voltage setting value and digital loop compensation parameter k p , k i , k d A PWM adjustment signal is generated, and the high-precision high-power converter is controlled by the PWM adjustment signal, so that the output voltage and current of the high-precision high-power converter are less affected by temperature and have a low temperature drift coefficient.

[0057] The temperature compensation device of the present invention can realize the calibration of current, voltage and distributed parameters, and further realize the temperature compensation control of the high-precision high-power converter in both steady-state and transient working states, so that it has a lower temperature drift coefficient and ensures higher output accuracy.

[0058] The embodiments of the utility model will be described in further detail below in conjunction with the accompanying drawings.

[0059] See also Figure 1 In the above-mentioned temperature compensation device, multiple temperature sampling units respectively perform temperature sampling on key parts of the output current precision sampling resistor, loop control circuit, output voltage feedback circuit, power switch device, magnetic element, and second-order filter circuit in the high-precision high-power converter to obtain temperature signals;

[0060] Since the output current precision sampling resistor and power switch devices are mostly installed on aluminum-based heat sinks, for these two devices under test, the temperature sensor can be packaged in TO-220 or TO-247, and the temperature sensor can be set using the "heat sink nearby pressure connection process", such as Figure 2 As shown; you can also use a lead packaged temperature sensor and use the "heat sink buried point process" to set the temperature sensor.

[0061] Since the loop control circuit and the output voltage feedback circuit are specific circuits soldered on the printed circuit board, and the change in circuit power loss is small, two temperature sensors are configured for each circuit to measure the surface temperature of the printed circuit board and the temperature of the space around the circuit respectively. The temperature sensor packages are SO-8 and TO-92, or similar packages. Finally, the influence factor is converted by the weight of each circuit, and the weight is the ratio of the circuit error to the output voltage error; the measured temperature decreases with the "printed circuit test point-specific circuit distance square", and compared with the ambient temperature, the maximum value is taken.

[0062] Since the magnetic components and the key parts of the second-order filter circuit, especially the converter output filter electrolytic capacitor, have a cylindrical structure that makes it difficult to measure the surface temperature, the embodiment of the present invention adopts the measurement process of "flexible circuit pasting process", such as Figure 3 As shown, a thick film flexible circuit board D with a locking contact F is specifically set as a flexible circuit pasting structure, and the surface-mounted temperature sensor E is arranged in the center of the circuit board using the thick film flexible circuit board. The bottom of the temperature sensor in the circuit board is hollowed out and coated with insulating thermal grease. The thick film flexible circuit board is pasted on the surface of the electrolytic capacitor perpendicular to the axial direction and is firmly spot welded through the locking contact; the thick film flexible circuit board is plugged into the main circuit board through the gold finger port. This "flexible circuit pasting process" solves the problem that the surface temperature of the electrolytic capacitor is difficult to measure, and has the advantages of high temperature measurement accuracy and fast speed, which lays a foundation for the subsequent determination of distribution parameters such as ESR and ESL through surface temperature conversion.

[0063] Specifically, the circuit structure of the multiple temperature sampling unit is as follows: Figure 4 As shown (but not limited to) Figure 4 The circuit is listed), because the types of temperature sensors selected by this unit are different, the circuit needs to normalize the sampling voltage. Because there is more than one temperature sensor for each key part or component being measured, the circuit can use normalization processing methods such as maximum value, average value, weighted average, etc. to obtain the final measured temperature signal, which is prepared for further data processing of the accuracy and stability control unit.

[0064] In the above-mentioned temperature compensation device, the accuracy and stability control unit includes: an input signal distribution circuit, an output current accuracy control module, an internal environment temperature control module, an output voltage accuracy control module and a stability control module; the main function of the accuracy and stability control unit is to further process and redistribute the normalized rough signals input by the multiple temperature sampling units according to different functions and weights, and transmit them to the microprocessors of each module in a differential manner (which can be microprocessors set separately for each module or shared microprocessors). Among them, the input signal distribution circuit is electrically connected to the output current accuracy control module, the internal environment temperature control module, the output voltage accuracy control module and the stability control module respectively; the output current accuracy control module mainly processes two temperature signals of the output current precision sampling resistor and the internal environment; the output voltage accuracy control module mainly processes three temperature signals of the loop control circuit, the output voltage feedback circuit and the internal environment; the stability control module mainly processes the temperature signals of key parts such as power switching devices, magnetic components, and second-order filter circuits.

[0065] Specifically, the input signal distribution circuit of the above-mentioned accuracy and stability control unit is as follows: Figure 5 As shown (but not limited to) Figure 5 The circuit is listed); the circuit selects multiple signals in series through a high-speed analog switch, performs common-mode rejection and signal source processing through a high-precision differential operational amplifier, and finally inputs the differential analog-to-digital converter to the microprocessor. This design uses a set of circuit structures to complete 8 groups of signal transmission, with the advantages of signal isolation, high common-mode rejection ratio, simple structure, etc. Its transmission effect is as follows Figure 6 As shown. Figure 6 It can be seen that the transmission period of each signal is only 20μs; when this circuit is used in practical applications to deal with different high-precision high-power converters, if the temperature compensation device has a large number of signal sources, the transmission period of each signal can be reduced to 1μs at the shortest, which can meet the sampling and transmission requirements of most power supplies.

[0066] In the above-mentioned temperature compensation device, the curve loading unit includes: a temperature drift curve calibration module, a temperature drift curve loading module and a distributed parameter curve loading module; the main function of the curve loading unit is to load three characteristic curves that change with temperature (i.e., current temperature drift characteristic curve, internal environment temperature drift characteristic curve and voltage temperature drift characteristic curve) into the temperature compensation device; the main characteristic quantities corresponding to the above three curves are "output current precision sampling resistance σR / R", "output voltage σU / U set" and "distributed parameter equivalent series resistance ESR". The temperature drift curve calibration module has a built-in microprocessor calibration circuit that provides a variety of communication interfaces such as USB, LAN, GPIB, RS485, etc., and is remotely connected to a programmable voltmeter, a programmable ammeter, a programmable electronic load, and an environmental test chamber through the communication interface; the programmable voltmeter and the programmable ammeter read the actual output voltage and current values, and the environmental test chamber and the programmable electronic load provide different internal ambient temperature values ​​for calibration; after entering the calibration mode, it can actively communicate with the remotely connected programmable voltmeter, programmable ammeter, programmable electronic load, and environmental test chamber and automatically perform calibration and curve drawing; Figure 7 This is a schematic diagram of the "output current precision sampling resistance σR / R" curve, which will be converted into recognizable list data and stored when loaded; at this point, all external conditions required for temperature compensation have been met, and the data is aggregated to the digital PWM adjustment unit.

[0067] In the above-mentioned temperature compensation device, the digital PWM adjustment unit is the final calculation and execution unit; the digital PWM adjustment unit calibrates the main characteristic quantities through the actual temperature value and the corresponding temperature drift curve, and the characteristic quantities include "output current precision sampling resistance value", "output voltage compensation value σU" and "distributed parameter equivalent series resistance ESR parameter"; these three main characteristic quantities will determine the "output current setting value", "output voltage setting value" and "digital loop compensation parameter k" according to the high-precision high-power converter fixed parameters and topological characteristic parameters. p , k i , k d "; The unit circuit generates a PWM adjustment signal according to the above three values ​​to drive the high-precision high-power converter, and finally makes the output voltage and current of the high-precision high-power converter have a low temperature drift coefficient and high stability.

[0068] The intelligent temperature compensation device of the present invention has at least the following beneficial effects:

[0069] 1) It can reduce the temperature coefficient of high-precision high-power converters working at extreme ambient temperatures to less than 20ppm, thereby greatly improving the output voltage and current accuracy;

[0070] 2) It can automatically adjust the control loop parameters according to the corresponding relationship between the measured temperature and the distribution parameters, thereby greatly improving the output stability in high and low temperature environments;

[0071] 3) The "flexible circuit application structure" adopted solves the problem that the converter output filter electrolytic capacitor has a cylindrical structure, which makes it difficult to measure the surface temperature and cannot provide accurate parameters for temperature compensation control;

[0072] 4) It has the function of automatic calibration of temperature drift curve, realizes active communication with remotely connected programmable voltmeter, programmable ammeter, programmable electronic load, environmental test chamber, and automatically performs calibration and curve drawing;

[0073] 5) All compensation and control processes can be automated and intelligent, and can be unattended.

[0074] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. An intelligent temperature compensation device for high-precision high-power converter, characterized in that: include: Multiple temperature sampling units, precision and stability control units, curve loading units and digital PWM adjustment units; among them, The multiple temperature sampling unit is provided with multiple groups of temperature sampling devices for connecting to the high-precision high-power converter, which can respectively obtain the temperature signals of different circuit parts of the high-precision high-power converter, and respectively normalize the obtained temperature signals of different circuit parts of the high-precision high-power converter to form a rough temperature signal output; The precision and stability control unit is electrically connected to the multiple temperature sampling unit and the curve loading unit, respectively, and can perform signal distribution processing and differentiation processing on the rough temperature signals corresponding to different circuit parts output by the multiple temperature sampling unit, and obtain the temperature signals corresponding to the current, internal environment, voltage, power switch device, magnetic element and second-order filter circuit respectively, and form a current temperature drift characteristic curve and a voltage temperature drift characteristic curve according to the temperature signals corresponding to the current and voltage respectively and the temperature signal corresponding to the internal environment; form a distributed parameter temperature drift characteristic curve according to the temperature signals corresponding to the power switch device, magnetic element and second-order filter circuit; The curve loading unit is electrically connected to the precision and stability control unit and the digital PWM adjustment unit, respectively, and can load the current temperature drift characteristic curve and the voltage temperature drift characteristic curve output by the precision and stability control unit and the distributed parameter temperature drift characteristic curve output by the precision and stability control unit to the digital PWM adjustment unit after calibrating them; The digital PWM adjustment unit is electrically connected to the curve loading unit and the high-precision high-power converter, respectively, and can form a PWM adjustment signal according to the current temperature drift characteristic curve, the voltage temperature drift characteristic curve and the distributed parameter temperature drift characteristic curve output by the curve loading unit, and control the high-precision high-power converter through the PWM adjustment signal; The multiple temperature sampling unit includes: a precision current feedback module, an internal environment temperature feedback module, an output voltage feedback module, a power switch temperature module, a magnetic element temperature module and a second-order filter temperature module; wherein, The precision current feedback module, the internal environment temperature feedback module, the output voltage feedback module, the power switch temperature module, the magnetic element temperature module and the second-order filter temperature module are each provided with a set of temperature sampling devices; Each group of temperature sampling devices of the precision current feedback module, the internal environment temperature feedback module, the output voltage feedback module, the power switch temperature module, the magnetic element temperature module and the second-order filter temperature module are respectively connected to the output current precision sampling resistor, the loop control circuit, the output voltage feedback circuit, the power switch device, the magnetic element, and the second-order filter circuit of the high-precision high-power converter, and can respectively collect temperature signals of each circuit part of the output current precision sampling resistor, the loop control circuit, the output voltage feedback circuit, the power switch device, the magnetic element, and the second-order filter circuit; The temperature sampling device of the precision current feedback module adopts a temperature sensor, which is connected to the aluminum-based heat sink connected to the output current precision sampling resistor by pressing the heat sink nearby or burying the heat sink; The temperature sampling device of the power switch temperature module adopts a temperature sensor, which is connected to the aluminum-based heat sink connected to the power switch device by pressing the heat sink nearby or burying the heat sink; The temperature sampling device of the internal environment temperature feedback module adopts two temperature sensors, wherein one temperature sensor is arranged on the surface of the printed circuit board of the loop control circuit, and the other temperature sensor is arranged in the space around the printed circuit board of the loop control circuit; The temperature sampling device of the output voltage feedback module adopts two temperature sensors, wherein one temperature sensor is arranged on the surface of the printed circuit board of the output voltage feedback circuit, and the other temperature sensor is arranged in the space around the printed circuit board of the output voltage feedback circuit; The temperature sampling device of the power switch temperature module adopts a temperature sensor with a hollow structure at the bottom, and the temperature sensor is arranged on a flexible circuit application structure, and the flexible circuit application structure is wound around the surface of the power switch device whose temperature is to be measured; The temperature sampling device of the magnetic element temperature module adopts a temperature sensor with a hollow structure at the bottom, and the temperature sensor is arranged on a flexible circuit application structure, and the flexible circuit application structure is wound and arranged on the surface of the magnetic element whose temperature is to be measured; The temperature sampling device of the second-order filter temperature module adopts a temperature sensor with a hollow structure at the bottom, and the temperature sensor is arranged on a flexible circuit application structure, and the flexible circuit application structure is wound around the surface of the filter electrolytic capacitor of the second-order filter circuit whose temperature is to be measured; The precision and stability control unit comprises: Input signal distribution circuit, temperature differentiation processing module, output current accuracy control module, internal environment temperature control module, output voltage accuracy control module and stability control module; wherein, The input signal distribution circuit is electrically connected to the multiple temperature sampling units, and is electrically connected to the output current precision control module, the internal environment temperature control module, the output voltage precision control module and the stability control module respectively through the temperature differentiation processing module, and can send each rough temperature signal output by the multiple temperature sampling units to the temperature differentiation processing module for signal distribution processing, and then distribute it to the output current precision control module, the internal environment temperature control module, the output voltage precision control module and the stability control module accordingly after size comparison and / or weight differentiation processing; The internal environment temperature control module is electrically connected to the output current accuracy control module and the output voltage accuracy control module respectively, and can receive the temperature signal corresponding to the internal environment after the differentiation process, and output it to the output current accuracy control module and the output voltage accuracy control module respectively; The output current precision control module can obtain the temperature signal corresponding to the current according to the temperature signals corresponding to the output current precision sampling resistor and the internal environment after the differentiation processing; The output voltage accuracy control module can obtain a temperature signal corresponding to the voltage according to the temperature signals corresponding to the output voltage feedback circuit and the internal environment after differentiation processing; The stability control module can obtain the temperature signal corresponding to the distribution parameter according to the temperature signals corresponding to the power switch device, the magnetic element, and the second-order filter circuit respectively after the difference processing; The curve loading unit includes: a temperature drift curve calibration module, a temperature drift curve loading module and a distribution parameter curve loading module; wherein, The temperature drift curve calibration module is electrically connected to the accuracy and stability control unit and the temperature drift curve loading module, and can communicate with the remotely connected programmable voltmeter, programmable ammeter, programmable electronic load, and environmental test box to automatically calibrate the current temperature drift characteristic curve and the voltage temperature drift characteristic curve received from the accuracy and stability control unit, and send the calibrated current temperature drift characteristic curve and the voltage temperature drift characteristic curve to the temperature drift curve loading module, and the characteristic quantities corresponding to the current temperature drift characteristic curve and the voltage temperature drift characteristic curve are the output current precision sampling resistance σR / R and the output voltage σU / U respectively. set ; The temperature drift curve loading module is electrically connected to the temperature drift curve calibration module and the digital PWM adjustment unit, respectively, and can load the current temperature drift characteristic curve and the voltage temperature drift characteristic curve received from the temperature drift curve calibration module into the digital PWM adjustment unit; The distributed parameter curve loading module is electrically connected to the precision and stability control unit and the digital PWM adjustment unit, respectively, and can load the distributed parameter temperature drift characteristic curve received from the precision and stability control unit to the digital PWM adjustment unit; the characteristic quantity corresponding to the distributed parameter temperature drift characteristic curve is the distributed parameter equivalent series resistance ESR.

2. The intelligent temperature compensation device for high-precision high-power converter according to claim 1, characterized in that: The precision current feedback module, the internal environment temperature feedback module, the output voltage feedback module, the power switch temperature module, the magnetic element temperature module and the second-order filter temperature module all adopt a temperature sampling circuit.

3. The intelligent temperature compensation device for high-precision high-power converter according to claim 1, characterized in that: The input signal distribution circuit includes: a high-speed analog switch multi-channel serial selection circuit, a high-precision differential operational amplifier and a differential analog-to-digital converter which are electrically connected.

4. The intelligent temperature compensation device for high-precision high-power converter according to claim 1, characterized in that: The digital PWM adjustment unit can calibrate the three characteristic quantities corresponding to the current temperature drift characteristic curve, the voltage temperature drift characteristic curve and the distributed parameter temperature drift characteristic curve through the current temperature drift characteristic curve, the voltage temperature drift characteristic curve and the distributed parameter temperature drift characteristic curve corresponding to the actual temperature value of the high-precision high-power converter, and obtain the three calibrated characteristic quantities, namely, the output current precision sampling resistance value, the output voltage compensation value σU, and the distributed parameter equivalent series internal resistance ESR. The output current setting value, the output voltage setting value and the digital loop compensation parameter k are determined according to the fixed parameters and topological characteristic parameters of the high-precision high-power converter through the three calibrated characteristic quantities. p , k i , k d , and according to the obtained output current setting value, output voltage setting value and digital loop compensation parameter k p , k i , k d A PWM adjustment signal is generated, and the high-precision high-power converter is controlled by the PWM adjustment signal.

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