RU1809533C - Code/power converter - Google Patents

Abstract

The invention relates to automatic control systems and can be used to fine-tune the power supplied to an object, for example, in temperature controllers and in temperature measurement, while stabilizing the thermal dissipation power of a resistive sensor. The purpose of the invention is to expand the scope of application. The goal is achieved by introducing into the converter comprising a series-connected current regulator, a current-limiting element on the resistor and a heater, first and second operational amplifiers, a voltage-to-time ratio converter and a code-controlled voltage divider. 1 ill.

Description

The invention relates to automatic control systems and can be used to precisely control the power supplied to an object, for example, in temperature controllers and when measuring temperature while stabilizing the thermal dissipation power of the sensor.

The purpose of the invention is to expand the scope.

The drawing shows a functional diagram of the device.

The code-power converter contains an input bus 1, a reference voltage input 2, a current controller 3 in series, a resistor 4 and a heater 5, operational amplifiers 6 and 7, a voltage-to-time ratio converter 8, a code-controlled divider 9. Second the input of the heater 5 is connected to the output and the inverting input of the amplifier 7, the non-inverting input of which is connected to a common bus. The output of the converter 8 is connected to the enable input of the controller

current 3, the first differential inputs with the terminals of the resistor 4, and the second with the input 2 of the reference voltage and a common bus. The ko, pre-controlled divider 9 is connected by the first output to the input 2 of the reference voltage, the second to the common bus, the output to the input of the amplifier 6, the control input to the bus 1. Another input of the amplifier 6 is connected to the connection point of the resistor 4 and heater 5, and the output is to the first control. to the current controller input.

The code-power converter operates as follows.

At the output of converter 8, a sequence of pulses is generated, the period T of which is given by the natural clock frequency of converter 8, and the duration: tn is determined by the offset of the reference voltage; voltage UO to the voltage drop U1 on the resistor 4. Moreover, T const,

UO U1

(1)

(L

WITH

00

o o e co

where K1 is the conversion coefficient of the Converter 8

TJK like, (

U1 I x RO (2) where I is the current flowing through the resistor 4 and the heater 5,

RO is the resistance of the resistor 4,

then expression (1) takes the form

, 1 and ° (31 K1T7gGO W On the heater 5, the voltage is set:

U2 K2xUO (4) defined by code K2 set at the control input of the code-controlled divider. In this case, the operational amplifier 6 is covered by negative feedback through the current controller 3 and the resistor 4.

During time tn, active power is released on the heater 5

(5) The average power of the PCP during the period T is determined by the expression:

 (b) It follows from (1), (5) and (6) that Pcp K1xK2xlxUOx -} - XROxT or

Pcp K1xK2x-RU0 ° xT (7)

For constant values of K1, DO, RO, T, the electric power Pcr is supplied to the heater 5 linearly only depends on the code K2 installed at the control input of the code-controlled divider 9, and does not depend on the resistance of the heater.

Thus, the functionality and scope of the device are greatly expanded.

An additional advantage of the claimed device is the possibility of using it as a functional converter of the input code into a time interval.

Indeed, it follows from (2), (3) and (4) that

T-i

what

t - to 1 v GOS (tn- RQ 18)

where RH is the resistance of the heater.

That is, when using equal reference resistors as elements 4 and 5, pulses of duration 1 will be generated at the output of converter 8

K2

Claims (1)

The formula for finding a Code-power converter containing a series-connected current controller, a current-limiting element made on a resistor, and a heater, a first operational amplifier, the output of which is connected to the first control the input of the current regulator, and the first input with the first output of the heater, the second operational amplifier, characterized in that in order to expand the scope of application, a converter is introduced into it the ratio of voltages in the time interval, the output of which is connected to the second control input of the current regulator, the first differential inputs are connected to the terminals of the resistor, and the second, respectively, to the buses of the reference voltage and zero potential, and a code-controlled voltage divider, the inputs of which are combined respectively with the second differential inputs of the converter the voltage ratio in the time interval, the output is connected to the second input of the first operational amplifier, and the control input is the input bus, while the inverting input and output 0 of the second operational amplifier is connected to the second terminal of the heater, and the non-inverting input is a zero potential bus. / ABOUT I V