RU-2861609-C1 - METHOD FOR COMPENSATING TEMPERATURE ERRORS IN VOLTAGE INCREMENT GENERATOR OF BRIDGE STRAIN GAUGE SENSOR SIGNAL SIMULATOR AND VOLTAGE INCREMENT GENERATOR FOR IMPLEMENTING THE SAME

RU2861609C1RU 2861609 C1RU2861609 C1RU 2861609C1RU-2861609-C1

Abstract

FIELD: measuring technology. SUBSTANCE: inventions are intended for compensating temperature errors in a voltage increment generator of a bridge strain gauge sensor signal simulator when the ambient temperature changes relative to 20°C within the operating temperature range of high-speed measurement systems. A method for compensating temperature errors in a voltage increment generator of a bridge strain gauge sensor signal simulator is proposed. The novelty of the claimed method is that the resistance values that are included in the equivalent circuit at a temperature of 20°C are measured, as well as the resistance increments with their signs relative to 20°C at the boundary temperatures of the calculated range of the generator. A temperature error compensation circuit is calculated, wherein the resistances of each arm of the generator in the equivalent circuit are replaced by real resistances measured at a temperature of 20°C, so that the resistance of the bridge arm is close to the resistance of the bridge arm of the simulated bridge strain gauge sensor, wherein the resistances of these resistors are selected taking into account their resistance increments with their signs, as a result of the calculation, ensuring that the sum of the resistances of the bridge arms of the first circuit differs minimally from the sum of the resistances of the bridge arms of the second circuit at a temperature of 20°C and at the boundary temperatures of the calculated temperature range of the generator. The values of the additional resistances in the first circuit, as well as in the second circuit, should differ from their calculated values by no more than ±1 mOhm, and the difference in the resistances of the generator arms connected at the power supply point should also be minimal. Based on the calculation results of the circuit relative to 20°C and at the boundary temperatures of the calculated range of the generator, the temperature error is determined; if it exceeds a predetermined value, the calculation is performed again, changing the resistance values both at a temperature of 20°C and at the boundary temperatures of the calculated range of the generator; if the temperature error does not exceed the predetermined value, the circuit is assembled on a breadboard and the generator is tested in a climatic chamber at 20°C and in the operating temperature range of the measurement system for which the voltage increment generator is being developed. If the tests do not confirm the predetermined temperature error, the steps of calculating the temperature compensation circuit of the generator are repeated; if the tests confirm the predetermined temperature error, the resistors are remounted onto the main board, after which a control check of the temperature compensation of the generator is carried out in a climatic chamber. A voltage increment generator of a bridge strain gauge sensor signal simulator is also proposed. EFFECT: reducing the temperature error of the voltage increment generator of a bridge strain gauge sensor signal simulator to a predetermined value. 2 cl, 3 dwg, 5 tbl

Inventors

ZUBOV EVGENIJ GEORGIEVICH
Levchenko Mikhail Aleksandrovich
Zagidullin Shamil Magamedovich

Dates

Publication Date: 20260506
Application Date: 20251215

Claims (2)

1. A method for compensating for temperature errors in a voltage increment step generator of a bridge strain gauge signal simulator, characterized in that in the voltage increment step generator, which is a resistor bridge consisting of two parallel-connected chains of series-connected resistors, the first and last of which in each chain are base resistors that are connected with their terminals to the bridge power inputs, and the remaining resistors of the chain are additional, wherein the first chain includes an even number m-1 of additional resistors with equal resistances, and the second chain includes an even number n-1 of additional resistors with equal resistances, the resistance of each additional resistor of the second chain is m times greater than each resistance of the additional resistor of the first chain, the resistances of the base resistors of the first chain differ from the resistances of the base resistors of the second chain and are selected from the condition that the sum of the resistances of one base and (m-1)/2 additional resistors of the first chain, multiplied by the additional resistance of this circuits, and the sum of the resistances of the base resistor and (n-1)/2 additional resistors of the second circuit, multiplied by the additional resistance of this circuit, form the arms of the bridge of the generator, the resistances of which are equal to the resistance of the arms of the simulated bridge strain gauge, m terminals of the first circuit and n terminals of the second circuit form the measuring diagonals, set the permissible value of the supply voltage or current, the number of steps that the generator must form, the range of voltage increments of the generator, the calculated temperature range of the generator and the value of the temperature error of the stages of the generator in percent in the form of the difference in resistance at the limit temperatures of the calculated temperature range of the generator and at a temperature of 20 °C, multiplied by 100 and divided by the range of voltage increments of the stages of the generator, calculate the resistance values of the additional and base resistors, calculate the increments of the output voltages of the generator and sort them from the maximum negative to zero and from zero to maximum positive, the values of the calculated resistances are replaced by equivalent resistance values, which are selected from resistors having resistances of the corresponding nominal series, characterized in that the values of the resistances that are included in the equivalent circuit at a temperature of 20 °C, and the increments of resistances with their signs relative to 20 °C at the boundary temperatures of the calculated range of the former, a temperature error compensation circuit is calculated, while the resistances of each arm of the former in the equivalent circuit are replaced by real resistances measured at a temperature of 20 °C, so that the resistance of the bridge arm is close to the resistance of the bridge arm of the simulated bridge strain gauge, while the resistances of these resistors are selected taking into account their increments of resistances with their signs, as a result of the calculation, it is achieved that the sum of the resistances of the bridge arms of the first circuit differs minimally from the sum of the resistances of the bridge arms of the second circuit at a temperature of 20 °C and at the boundary temperatures of the calculated temperature range the shaper, the values of additional resistances in the first circuit, as well as in the second circuit, must differ from their calculated values by no more than ±1 mOhm, and the difference in the resistance of the shaper arms connected at the point of application of power must also be minimal, based on the results of circuit calculations relative to 20 ° C and at the boundary temperatures of the shaper's calculated range, the temperature error is determined, if it exceeds the specified value, then the calculation is repeated, changing the resistance values both at a temperature of 20 ° C and at the boundary temperatures of the shaper's calculated range, if the temperature error does not exceed the specified value, then the circuit is mounted on a breadboard and the shaper is tested in a climatic chamber at 20 ° C and in the operating temperature range of the measuring system for which the step shaper is being developed, if the tests do not confirm the specified temperature error, then the operations of calculating the temperature compensation circuit of the shaper are repeated, if the tests confirm the specified temperature error, then The resistors are remounted on the main board, after which a control test of the temperature compensation of the generator is carried out in a climatic chamber.
2. A voltage increment step generator of a bridge strain gauge signal simulator, which is a resistor bridge consisting of two parallel-connected chains of series-connected resistors, the first and last of which in each chain are base resistors, which are connected with their terminals to the bridge power inputs, and the remaining resistors of the chain are additional, wherein the first chain includes an even number m-1 of additional resistors with equal resistances, and the second chain includes an even number n-1 of additional resistors with equal resistances, the resistance of each additional resistor of the second chain is m times greater than each resistance of an additional resistor of the first chain, the resistances of the base resistors of the first chain differ from the resistances of the base resistors of the second chain and are selected from the condition that the resistances of each arm of the resistor bridge generator are equal to the nominal resistance of each strain gauge of the simulated bridge sensor, m terminals of the first chain and n terminals of the second chain form measuring diagonals, at the outputs of which the steps of the voltage increments of the driver are formed, characterized in that in the circuits of the base resistors, in each arm of the driver bridge, maximum resistance values are set, which are equal for all arms of the driver bridge, the nominal resistance values of the resistors are replaced by the actual resistances of the resistors, which are measured at a temperature of 20°C and at the boundary temperatures of the calculated temperature range of the driver, while the maximum resistance values of the circuits of the base resistors have the same sign of the temperature increment, a temperature error compensation circuit is calculated, while the resistances of each arm of the driver in the equivalent circuit are replaced by the actual resistances measured at a temperature of 20°C, so that the resistance of each arm of the driver bridge is close to the resistance of each arm of the bridge of the simulated sensor, while the resistances of these resistors are selected taking into account their resistance increments with their own signs, as a result of the calculation, the sum of the resistances the arms of the first circuit differ minimally from the sum of the resistances of the arms of the second circuit at a temperature of 20°C and at the boundary temperatures of the calculated temperature range of the former, the resistance values of the additional resistors in the first circuit, as well as in the second circuit, differ from their calculated values by no more than ±1 mOhm, and the difference in the resistances of the arms of the bridge of the former, connected at the point of application of power, is also minimal, while the difference between the resistances of the arms of the bridge, connected to the power diagonal with a negative current value, should be no more than 1 mOhm, the temperature error is determined based on the results of circuit calculations relative to 20°C and at the boundary temperatures of the calculated temperature range of the former.

Description

The inventions relate to measuring equipment and are intended to compensate for temperature errors in the voltage increment step generator of the signal simulator of bridge strain gauge sensors when the ambient temperature changes relative to 20°C within the operating temperature range of high-speed measuring systems. Bridge strain gauge sensors for force, pressure, displacement, and other measurements are used in various fields of technology. The measuring systems to which these sensors are connected are equipped with bridge strain gauge signal simulators. These simulators are designed for testing measuring systems during operation. To improve the accuracy of physical measurement, signal simulators are used to calibrate systems immediately before measurements, and during measurements, the simulators are used to quickly monitor the performance of these measuring systems. The ability to use a signal simulator for verification and calibration of a measuring system determines the error with which the signal simulator's voltage increment steps are generated within its design temperature range. Verification of measuring systems is performed under normal conditions at temperatures of 20±5°C. This is primarily due to the technical capabilities of the verification equipment used. The operating temperature range of most measuring systems designed for measuring the voltage increments of bridge strain gauges ranges from 15°C to 35°C. While normal conditions can be ensured during verification, which is performed periodically, for example, once a year, to improve measurement accuracy, calibration of the measuring systems in their operating range should be performed immediately prior to measurements. To ensure reliable system operation, voltage increments from the signal simulator should be measured during each cycle of sensor signal measurements from the test object during the experiment. Known voltage increment step generators do not allow for compensation of temperature errors to a value that would ensure verification, calibration, and operational monitoring of the performance of measuring systems with a given error. To enable the use of signal simulators for verification, calibration, and operational monitoring of measuring systems, it is necessary to compensate for the temperature errors of existing shapers within the operating temperature range of the measuring systems. A variant of such a method and a voltage increment shaper are proposed in this patent application. A method for compensating for temperature errors in a resistance increment step generator of a strain gauge signal simulator and a resistance increment step generator of a strain gauge signal simulator for implementing the same is known (Patent No. 2836602, 2025), which consists in the fact that in the resistance increment step generator of a strain gauge signal simulator, the number of steps that the generator must generate, the range of the generator resistance increment relative to the nominal resistance of the simulated strain gauge, the operating temperature range of the generator and the value of the temperature error of the generator steps are specified, the generator circuit is calculated, the calculated circuit is replaced with an equivalent circuit in which the calculated resistances of the resistors are replaced with resistors whose resistances are included in the nominal series of resistor resistances, for the resistances that are included in the equivalent circuit, the actual resistances are measured at a temperature of 20°C and their temperature coefficients of resistance (TCR) with their signs in the operating temperature range of the converter, calculate the compensation circuit for the temperature error of the former by replacing the resistors from the nominal series in the equivalent circuit with the real resistances of the resistors at a temperature of 20°C, taking into account the TCR of the resistors in the operating temperature range. The disadvantage of the known method is that it is impossible for the former of the resistance increments of the strain gauge signal simulator to form the steps of the voltage increments of the signal simulator of the bridge strain gauge sensors. A method is known for setting up strain gauge sensors with a bridge measuring circuit for additive temperature error (RU Patent No. 2276325, 2004), which consists in pre-balancing the bridge circuit, determining the TCR of all the arms of the bridge circuit taking into account the introduction of a balancing resistor during preliminary balancing and determining the arm of the balanced sensor into which a temperature-independent compensating resistor is connected in parallel with the working strain gauge, determining the arm into which the balancing temperature-independent resistor will be connected, after setting up the sensor from the condition of series connection with the working strain gauge in the same arm, or in the opposite arm relative to the arm of