METHOD FOR PROVIDING LINEARITY OF PENDULOUS ACCELEROMETER SCALE COEFFICIENT OF COMPENSATION TYPE Russian patent published in 2017 - IPC G01P15/13 G01P15/00 

FIELD: physics.

SUBSTANCE: method for providing the linearity of the pendulous accelerometer scale factor of the compensatory type refers to the measuring technique. The method is based on using digital feedback implemented by microcontroller, which programmatically implemented PWM; the PWM generates a sequence of working pulses, the duration of which is equal to τ_work(n⋅T₀), and the timer of the microcontroller generates two equal size auxiliary pulses with the duration of τ_aux and two equal pauses with the duration of τ_pauses. The method specifies the rule for selecting the duration of the working pulse interval τ_work(n⋅T₀), the duration of auxiliary pulses and pauses at the "n"-th sampling clock, as well as the rule of mutual placement on each "n"-th sampling clock of the working, auxiliary pulses and pauses. At the beginning of each "nT₀"-the sampling cycle, the first auxiliary pulse current is located; the working pulse is joined to this auxiliary current pulse; after a certain period of time in the time interval T₀ the second auxiliary pulse is located, wherein the sign of the first auxiliary pulse coincides with the sign of the working pulse, and the sign of the second auxiliary pulse is opposite to the sign of the working pulse. The average current value I_av, which enters the winding of the moment sensor, is expressed in terms of constant amplitude of the current in the pulse I_a, the duration of the working pulse τ_work(nT₀) and the period T₀ of the PWM operation, i.e. I_av=I_a⋅τ_work(nT₀)/T₀. The product of⋅I_a⋅τ_work(n⋅T₀) is a perfect square rectangular pulse, which distorted the transitional processes in the front AC fronts of the winding torque sensor. The required linearity of the conversion can be achieved, if two equal auxiliary pulses of different polarities are fed during the PWM period, and one of them is connected to the working pulse of duration τ_work(nT₀), the transient processes will not distort the area of the working pulse I_a⋅τ_work(nT₀), as the transient processes on the leading edges of the pulses are mutually compensated with a certain accuracy, and the average value over the period of the T₀ current flowing into the winding of the torque sensor, will be proportional only to the duration of the working pulse, i.e. to the measured linear acceleration.

EFFECT: ensuring the linearity of the scale factor of the pendulous accelerometer of the compensatory type.

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