CN115200732A - Compensation type RTD measuring circuit of vehicle charging module - Google Patents
Compensation type RTD measuring circuit of vehicle charging module Download PDFInfo
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K7/00—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements
- G01K7/16—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements
- G01K7/18—Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply therefor, e.g. using thermoelectric elements using resistive elements the element being a linear resistance, e.g. platinum resistance thermometer
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/007—Regulation of charging or discharging current or voltage
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
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Abstract
The invention relates to a compensation type RTD measuring circuit of a vehicle charging module, wherein a low-voltage output circuit of an RTD input source is formed by a regulating resistor R4 and an operational amplifier U1A; the operational amplifier U1B and the regulating resistor R3 form a driving voltage regulator, and the U1B is connected with one end of the compensating resistor R9 to form a high-voltage output circuit of the RTD input source; two ends of a compensation resistor R9 are respectively connected with the low-voltage output and the high-voltage output of the RTD input source; an operational amplifier U2, adjusting resistors R5-R8, a compensation resistor R10, a protection diode D2 and a protection resistor R12 form an RTD compensation source circuit, operational amplifiers U3A and U3B and the RTD form a differential follower circuit, and amplifying adjusting resistors R21-R25 and U5A form a differential amplifier circuit; the filter resistors R27 and U5 and the filter capacitor C1 form an RC low-pass filter circuit; by designing the RTD compensation acquisition circuit and the differential amplification filter circuit, the problems of strong signal interference, low signal stability, high RTD remote measurement impedance and the like of a charging module unit of a high-power vehicle in temperature measurement are solved.
Description
Technical Field
The invention belongs to the field of new energy automobile charging signal processing circuit design, and particularly relates to a compensation type RTD measuring circuit of a vehicle charging module.
Background
The new energy electric vehicle charging facility industry is in a rapid development period, and as the new energy electric vehicle charging technology becomes mature, the charging power is continuously improved, so that the power unit of the charging module is also continuously improved; temperature is one of the key parameters for calculating current, voltage, SOC, protection, etc. in designing a charging module, and therefore the accuracy and real-time of temperature measurement are very important in designing a charging module.
Common types of RTDs include PT100, PT200, PT1000 and the like, and have the characteristics of high precision, good stability, wide measurement range and the like; along with the design of the charging module power unit is higher and higher, particularly, the factors such as strong interference of temperature measurement signals of components such as DC output of the power unit more than 40KW, a transformer and the like, low signal stability, high RTD remote measurement impedance and the like have high requirements on measurement accuracy, instantaneity and anti-interference capability, the measurement is inaccurate, the comprehensive performance of the vehicle charging module unit is poor, and the working efficiency is influenced.
Disclosure of Invention
In order to solve the technical problems, the invention provides a compensation type RTD measurement circuit of a vehicle charging module, which solves the problems of strong signal interference, low signal stability, high RTD remote measurement impedance and the like of temperature measurement in a high-power vehicle charging module unit through the design of an RTD compensation acquisition circuit and a differential amplification filter circuit.
In order to achieve the purpose, the invention adopts the following technical scheme:
a compensation type RTD measuring circuit of a vehicle charging module comprises a compensation acquisition circuit and a differential amplification filter circuit, wherein the compensation acquisition circuit comprises operational amplifiers U1 and U2, adjusting resistors R1-R8, compensation resistors R9 and R10, protection diodes D1 and D2, protection resistors R11 and R12, a reference resistor R13 and a margin resistor R14; the differential amplification filter circuit comprises U3-U5, amplification adjusting resistors R20-R26, a filter resistor R27 and a filter capacitor C1; one end of an adjusting resistor R4 is connected with a reference power supply, the other end of the adjusting resistor R4 is connected with the positive input of the operational amplifier U1A, the adjusting resistor R1 is a negative feedback resistor of the operational amplifier U1A, one end of the adjusting resistor R1 is connected with the output of the operational amplifier U1A, the other end of the adjusting resistor R1 is connected with the negative input of the operational amplifier U1A and is connected with one end of an adjusting resistor R2, and the other end of the adjusting resistor R2 is connected with the ground, so that a low-voltage output circuit of an RTD input source is formed; the negative electrode input and the output of the operational amplifier U1B are connected to form a voltage follower, the voltage follower is connected with one end of the regulating resistor R3, the other end of the R3 is connected with the positive electrode input of the U1A to form a driving voltage regulator, and the positive electrode input of the U1B is connected with one end of the compensating resistor R9 to form a high-voltage output circuit of the RTD input source; two ends of a compensation resistor R9 are respectively connected with the low-voltage output and the high-voltage output of the RTD input source; the protection diode D1 and the protection resistor R11 are connected to form a stable source protection circuit; one end of the protection resistor R11 is connected with the RTD input and provides an input source of the RTD; an operational amplifier U2, adjusting resistors R5-R8, a compensation resistor R10, a protection diode D2 and a protection resistor R12 form an RTD compensation source circuit, and the principle of the RTD compensation source circuit is similar to that of an input source circuit of an RTD; the output of the RTD compensation source is connected with the first output end of the RTD and is used for compensating errors generated by the lead resistance of the RTD; the second output end of the RTD is connected with one end of a reference resistor R13, the R13 is connected with one end of a margin resistor R14, the other end of the R14 is connected with the ground, two ends of the R13 provide a reference power supply for the acquisition circuit, and the R14 provides a margin voltage for the circuit and serves as a buffer voltage of the reference power supply; the positive input ends of the operational amplifiers U3A and U3B are respectively connected with the input end and the first output end of the RTD, and the negative input ends of the operational amplifiers U3A and U3B are respectively connected with the output ends to form a differential follower circuit, so that the impedance of the RTD differential input is improved, and the input driving capability is improved; two ends of the amplifying and adjusting resistors R20 and R23 are respectively connected with the input and the output of the negative terminals of the U4A and the U4B, two ends of the amplifying and adjusting resistor R26 are respectively connected with the input of the negative terminals of the U4A and the U4B, and the input of the positive terminals of the U4A and the U4B is respectively connected with the output of the U3A and the U3B, so that a negative feedback adjusting circuit with differential input is formed; two ends of an amplification adjusting resistor R21 are respectively connected with the input of the positive end of the U5A and the output of the U4A, two ends of an amplification adjusting resistor R24 are respectively connected with the input of the negative end of the U5A and the output of the U4B, two ends of an amplification adjusting resistor R22 are respectively connected with the input and the output of the positive end of the U5A, and two ends of an amplification adjusting resistor R25 are respectively connected with the input of the negative end of the U5A and the ground to form a differential amplification circuit; two ends of a filter resistor R27 are respectively connected with the U5A output end and the sampling output end, and two ends of a filter capacitor C1 are respectively connected with the sampling output end and the ground to form an RC low-pass filter circuit;
the circuit provides two voltages, namely a working voltage and a reference voltage, wherein the working voltage is direct current voltage of 5V to 16V; the reference voltage Vref is converted into a rear-end sampling reference power supply, an RTD input source and an RTD compensation source respectively through a compensation acquisition circuit;
the RTD input source in the compensated acquisition circuit is determined by the following equation,
in the formula:
v2 is the high voltage of the RTD input source,
v1 is the low voltage of the RTD input source,
taking R1= R2= R3= R4, we find:
the RTD input source current is given by the following equation:
the RTD compensation source current in the compensation acquisition circuit is determined by the equation,
the back end sampling reference power supply in the compensation acquisition circuit is determined by the following formula,
the differential amplification filter circuit requires R20= R23, R21= R24, R22= R25, the output sampling voltage is determined by the following formula,
in the formula:
Compared with the prior art, the invention has the following beneficial effects:
(1) The driving source circuit and the feedback compensation source circuit adopt the same reference input source to generate adjustable excitation output through operational amplifier following and feedback adjustment, have the characteristics of strong driving force, high precision, interference resistance and small mismatch drift, and are used as RTD (reverse time detection) reverse excitation, so that errors caused by excitation fluctuation can be eliminated; the driving source circuit is a forward excitation input and is connected with an input end of the RTD through the source stabilizing protection circuit, forward voltage is generated between the input end and the RTD, the feedback compensation source circuit is a reverse compensation input and is connected with a first output end of the RTD through the source stabilizing protection circuit, reverse voltage is generated between the first output end and the RTD, so that voltage drop generated by the input end is counteracted, errors generated by the RTD are effectively and dynamically compensated and collected, and other outputs of the RTD have no influence on a sampling signal; sampling signals at two ends of the RTD are input into a differential amplification filter circuit, a front stage and a differential follower circuit are used as cache isolators, and a rear stage is input into a differential regulation negative feedback circuit, so that the phenomena of fluctuation and drifting of the collected input signals due to external interference are effectively inhibited, and the problem of nonlinear output of the RTD is effectively solved; the compensation acquisition circuit and the differential amplification filter circuit adopt the same reference source, and provide reference voltage for back-end acquisition in the compensation acquisition circuit, so that errors caused by excitation current fluctuation can be eliminated, the RTD acquisition stability is effectively improved, and the working efficiency is improved;
(2) The RTD platinum resistor access circuit is used for processing and inputting the RTD platinum resistor into an acquisition chip for processing through a compensation acquisition circuit and a differential amplification filter circuit, a final temperature value is obtained by adopting a Callender-Van Dusen formula, and a large amount of practical verification is carried out on vehicle charging module equipment, so that the problems of instability of signal fluctuation, signal interference intensity, remote measurement impedance and the like in current sampling can be effectively solved, the nonlinear output of RTD is effectively improved, real-time RTD signal output with high precision, interference resistance, low drift, low noise and high stability is realized, the parameters of a vehicle charging module needing temperature drift and temperature compensation calculation are effectively guaranteed, and the comprehensive performance of a vehicle charging module unit is improved; in practical applications, the class B PT100 platinum resistance is measured at-70 ℃ to 250 ℃ with an accuracy of ± (0.2% FS +0.5% RD), an error of ≦ 0.93 ℃, and an RTD lead error of ≦ 0.015 ℃ C/Ω.
Drawings
FIG. 1 is a circuit diagram of a compensation acquisition circuit of the present invention;
FIG. 2 is a circuit diagram of the differential amplification filter of the present invention;
fig. 3 is a schematic diagram of a compensated RTD measurement for a vehicle charging module.
Detailed Description
The invention is further described below with reference to the drawings and examples.
The embodiment is applied to a 40KW constant-power module for vehicle charging, the maximum output voltage of the module is 1000VDC, the maximum output current of the module is 160A, 7 key points of inputting EMC, PFC, output monitoring and the like are all provided with the compensation type RTD measuring circuit of the vehicle charging module, the RTD adopted in the embodiment is class B PT100, the maximum measuring distance is 7 meters, the measuring temperature range is-150 ℃ to 600 ℃, the precision obtained by verification is +/-plus or minus (0.2 FS +0.5 RD), the error is less than or equal to 0.93 ℃, and the RTD lead error is less than or equal to 0.015 ℃ per omega.
As shown in fig. 1 and 2, a compensation type RTD measurement circuit of a vehicle charging module includes a compensation acquisition circuit and a differential amplification filter circuit, where the compensation acquisition circuit includes operational amplifiers U1 and U2, adjusting resistors R1 to R8, compensation resistors R9 and R10, protection diodes D1 and D2, protection resistors R11 and R12, a reference resistor R13, and a margin resistor R14; the differential amplification filter circuit comprises U3-U5, amplification adjusting resistors R20-R26, a filter resistor R27 and a filter capacitor C1; one end of an adjusting resistor R4 is connected with a reference power supply, the other end of the adjusting resistor R4 is connected with the positive input of the operational amplifier U1A, the adjusting resistor R1 is a negative feedback resistor of the operational amplifier U1A, one end of the adjusting resistor R1 is connected with the output of the operational amplifier U1A, the other end of the adjusting resistor R1 is connected with the negative input of the operational amplifier U1A and is connected with one end of an adjusting resistor R2, and the other end of the adjusting resistor R2 is connected with the ground, so that a low-voltage output circuit of an RTD input source is formed; the negative electrode input and the output of the operational amplifier U1B are connected to form a voltage follower and are connected with one end of the regulating resistor R3, the other end of the R3 is connected with the positive electrode input of the U1A to form a driving voltage regulator, and the positive electrode input of the U1B is connected with one end of the compensation resistor R9 to form a high-voltage output circuit of the RTD input source; two ends of the compensation resistor R9 are respectively connected with the low-voltage output and the high-voltage output of the RTD input source; the protection diode D1 and the protection resistor R11 are connected to form a stable source protection circuit; one end of the protection resistor R11 is connected with the RTD input and provides an input source of the RTD; an operational amplifier U2, adjusting resistors R5-R8, a compensation resistor R10, a protection diode D2 and a protection resistor R12 form an RTD compensation source circuit, and the principle of the RTD compensation source circuit is similar to that of an input source circuit of an RTD; the output of the RTD compensation source is connected with the first output end of the RTD and is used for compensating errors generated by the lead resistance of the RTD;
the driving source circuit and the feedback compensation source circuit adopt the same reference input source to generate adjustable excitation output through operational amplifier following and feedback adjustment, have the characteristics of strong driving force, high precision, interference resistance and small mismatch drift, and are used as RTD reverse excitation, so that errors caused by excitation fluctuation can be eliminated; the driving source circuit is the forward excitation input, be connected with RTD's input through steady source protection circuit, produce forward voltage between input and the RTD, feedback compensation source circuit is reverse compensation input, be connected with RTD's first output through steady source protection circuit, produce reverse voltage between first output and the RTD, thereby offset the pressure drop that the input produced, the error that the RTD produced is gathered in effectual dynamic compensation, and other outputs of RTD do not have the influence to the sampled signal.
The second output end of the RTD is connected with one end of a reference resistor R13, the R13 is connected with one end of a margin resistor R14, the other end of the R14 is connected with the ground, two ends of the R13 provide a reference power supply for the acquisition circuit, and the R14 provides a margin voltage for the circuit and serves as a buffer voltage of the reference power supply; the positive input ends of the operational amplifiers U3A and U3B are respectively connected with the input end and the first output end of the RTD, and the negative input ends of the operational amplifiers U3A and U3B are respectively connected with the output ends to form a differential follower circuit, so that the impedance of the RTD differential input is improved, and the input driving capability is improved; two ends of the amplification and regulation resistors R20 and R23 are respectively connected with the input and the output of the negative terminals of U4A and U4B, two ends of the amplification and regulation resistor R26 are connected with the input of the negative terminals of U4A and U4B, and the input of the positive terminals of U4A and U4B is respectively connected with the output of U3A and U3B, so that a negative feedback regulation circuit with differential input is formed; two ends of an amplification adjusting resistor R21 are respectively connected with the positive end input and the U4A output of the U5A, two ends of an amplification adjusting resistor R24 are respectively connected with the negative end input and the U4B output of the U5A, two ends of an amplification adjusting resistor R22 are respectively connected with the positive end input and the U5A output, and two ends of an amplification adjusting resistor R25 are respectively connected with the negative end input and the ground of the U5A to form a differential amplification circuit; two ends of a filter resistor R27 are respectively connected with the U5A output end and the sampling output end, and two ends of a filter capacitor C1 are respectively connected with the sampling output end and the ground to form an RC low-pass filter circuit; sampling signals at two ends of the RTD are input into the differential amplification filter circuit, the front stage and the differential follower circuit are used as a buffer isolator, the rear stage is input into the differential regulation negative feedback circuit, the phenomenon that the collected input signals are fluctuated and drifted by external interference is effectively inhibited, and the nonlinear output problem of the RTD is effectively improved.
The circuit provides two kinds of voltages, namely working voltage and reference voltage, wherein the working voltage is direct current voltage 12V; the reference voltage Vref is respectively converted into a rear-end sampling reference power supply, an RTD input source and an RTD compensation source through a compensation acquisition circuit, and the reference voltage adopted by the embodiment is 2.5V;
the RTD input source in the compensated acquisition circuit is determined by the following equation,
in the formula:
v2 is the high voltage of the RTD input source,
v1 is the low voltage of the RTD input source;
taking R1= R2= R3= R4, we find:
the RTD input source current is given by the following equation:
the present example uses a resistance of 10K for R9, an accuracy of 0.1%,
=250uA。
the RTD compensation source current in the compensation acquisition circuit is determined by the equation,
the R10 resistance value is 10K, the precision is 0.1 percent,
=250uA。
the rear-end sampling reference power supply in the compensation acquisition circuit is determined by the following formula,
the present example uses a resistance of 5.11K for R13, an accuracy of 0.1%,
=2.555V。
in the compensation acquisition circuit in the embodiment, the excitation input generates a boosting error due to impedance, the first output end of the RTD injects dynamic compensation excitation to eliminate the boosting error generated by the impedance, when the measurement temperature is 600 ℃, the temperature signal value is 78.8275mV, and the provided rear-end sampling reference voltage is 2.555V.
The differential amplification filter circuit requires R20= R23, R21= R24, R22= R25, the output sampling voltage is determined by the following formula,
in the formula:
In the example, the resistance value of R26 is 1K, the resistance value of R20 is 7.5K, the resistance value of R25 is 20K, the resistance value of R24 is 10K, the precision is 0.1%, the gain of the differential amplification filter circuit is 32, and when the measured temperature is 600 ℃, the temperature signal value is 2.52248V.
In the embodiment, the signal value output by the differential amplification filter circuit is processed by AD acquisition and is calculated by a Callender-Van Dusen formula to obtain the final temperature value.
As shown in fig. 3, the compensation RTD measurement circuit of a vehicle charging module according to the present invention is formed by a reference power source respectively converted into an RTD driving source and an RTD feedback compensation source through a compensation acquisition circuit, and connected to a first input terminal and a first output terminal of an RTD, so as to serve as dynamic output sources for acquiring RTD signal values and feedback compensation RTD values, and provide a reference power source for a rear-end sampling circuit through a constant-current voltage regulator circuit; the RTD signal value is adjusted through feedback, and through differential amplification filter circuit, the signal output that is high impedance, high accuracy, anti-interference, low drift, low noise, stability are high is converted into to the RTD signal.
Claims (4)
1. A compensation type RTD measuring circuit of a vehicle charging module is characterized by comprising a compensation acquisition circuit and a differential amplification filter circuit, wherein the compensation acquisition circuit comprises operational amplifiers U1 and U2, adjusting resistors R1-R8, compensation resistors R9 and R10, protection diodes D1 and D2, protection resistors R11 and R12, a reference resistor R13 and a margin resistor R14; the differential amplification filter circuit comprises U3-U5, amplification adjusting resistors R20-R26, a filter resistor R27 and a filter capacitor C1; one end of an adjusting resistor R4 is connected with a reference power supply, the other end of the adjusting resistor R4 is connected with the positive input of the operational amplifier U1A, the adjusting resistor R1 is a negative feedback resistor of the operational amplifier U1A, one end of the adjusting resistor R1 is connected with the output of the operational amplifier U1A, the other end of the adjusting resistor R1 is connected with the negative input of the operational amplifier U1A and is connected with one end of an adjusting resistor R2, and the other end of the adjusting resistor R2 is connected with the ground, so that a low-voltage output circuit of an RTD input source is formed; the negative electrode input and the output of the operational amplifier U1B are connected to form a voltage follower and are connected with one end of the regulating resistor R3, the other end of the R3 is connected with the positive electrode input of the U1A to form a driving voltage regulator, and the positive electrode input of the U1B is connected with one end of the compensation resistor R9 to form a high-voltage output circuit of the RTD input source; two ends of a compensation resistor R9 are respectively connected with the low-voltage output and the high-voltage output of the RTD input source; the protection diode D1 and the protection resistor R11 are connected to form a stable source protection circuit; one end of the protection resistor R11 is connected with the RTD input and provides an input source of the RTD; an operational amplifier U2, adjusting resistors R5-R8, a compensation resistor R10, a protection diode D2 and a protection resistor R12 form an RTD compensation source circuit, and the principle of the RTD compensation source circuit is similar to that of an input source circuit of an RTD; the output of the RTD compensation source is connected with the first output end of the RTD and is used for compensating errors generated by the lead resistance of the RTD; a second output end of the RTD is connected with one end of a reference resistor R13, the R13 is connected with one end of a margin resistor R14, the other end of the R14 is connected with the ground, two ends of the R13 provide a reference power supply for the acquisition circuit, and the R14 provides a margin voltage for the circuit to serve as a buffer voltage of the reference power supply; the positive input ends of the operational amplifiers U3A and U3B are respectively connected with the input end and the first output end of the RTD, and the negative input ends of the operational amplifiers U3A and U3B are respectively connected with the output ends to form a differential follower circuit, so that the impedance of the RTD differential input is improved, and the input driving capability is improved; two ends of the amplifying and adjusting resistors R20 and R23 are respectively connected with the input and the output of the negative terminals of the U4A and the U4B, two ends of the amplifying and adjusting resistor R26 are respectively connected with the input of the negative terminals of the U4A and the U4B, and the input of the positive terminals of the U4A and the U4B is respectively connected with the output of the U3A and the U3B, so that a negative feedback adjusting circuit with differential input is formed; two ends of an amplification adjusting resistor R21 are respectively connected with the positive end input and the U4A output of the U5A, two ends of an amplification adjusting resistor R24 are respectively connected with the negative end input and the U4B output of the U5A, two ends of an amplification adjusting resistor R22 are respectively connected with the positive end input and the U5A output, and two ends of an amplification adjusting resistor R25 are respectively connected with the negative end input and the ground of the U5A to form a differential amplification circuit; two ends of a filter resistor R27 are respectively connected with the U5A output end and the sampling output end, and two ends of a filter capacitor C1 are respectively connected with the sampling output end and the ground to form an RC low-pass filter circuit;
the circuit provides two voltages, namely a working voltage and a reference voltage, wherein the working voltage is direct current voltage of 5V to 16V; the reference voltage Vref is converted into a rear-end sampling reference power supply, an RTD input source and an RTD compensation source respectively through a compensation acquisition circuit;
the RTD input source in the compensation acquisition circuit is determined by the equation,
in the formula:
v2 is the high voltage of the RTD input source,
v1 is the low voltage of the RTD input source,
taking R1= R2= R3= R4, we find:
the RTD input source current is given by the following equation:
2. the compensated RTD measurement circuit of claim 1, wherein the RTD compensation source current in the compensation acquisition circuit is determined by the equation,
3. the compensated RTD measurement circuit of claim 1, wherein the back-end sampled reference supply in the compensated acquisition circuit is determined by the equation,
4. the compensated RTD measurement circuit of claim 1, wherein the differential amplification filter circuit requires R20= R23, R21= R24, R22= R25, the output sampling voltage is determined by the following formula,
in the formula:
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| CN110912399A (en) * | 2019-12-11 | 2020-03-24 | 国网山东省电力公司济南供电公司 | Time domain power supply system of temperature sensor |
| CN112595429A (en) * | 2020-08-12 | 2021-04-02 | 襄阳航力机电技术发展有限公司 | Platinum resistance temperature sampling device with compensation |
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2022
- 2022-05-31 CN CN202210603350.1A patent/CN115200732A/en active Pending
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| US20080011064A1 (en) * | 2006-07-11 | 2008-01-17 | Carl Masser | Apparatus and method of amplifying low voltage signals |
| CN101109662A (en) * | 2006-07-17 | 2008-01-23 | 梅特勒-托利多仪器（上海）有限公司 | Thermal resistance temperature surveying circuit |
| CN102244464A (en) * | 2011-07-08 | 2011-11-16 | 西安天照伟成电气有限公司 | Power circuit |
| US20180019718A1 (en) * | 2016-07-18 | 2018-01-18 | Hamilton Sundstrand Corporation | Differential signal conditioner with common mode voltage error compensation |
| CN110912399A (en) * | 2019-12-11 | 2020-03-24 | 国网山东省电力公司济南供电公司 | Time domain power supply system of temperature sensor |
| CN112595429A (en) * | 2020-08-12 | 2021-04-02 | 襄阳航力机电技术发展有限公司 | Platinum resistance temperature sampling device with compensation |
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