SU903931A1 - Shaft angular position-to-code converter - Google Patents

Description

The invention relates to automation, computing and information technology, and 3 navigation techniques can be used to convert the signals of rotary transformers into a code.

A known shaft angle converter is a code containing sine-cosine sensors, the outputs of which are connected to the inputs of switches connected to operational amplifiers, a code-to-voltage converter, a comparison unit, a control unit whose output is connected to the first code-voltage converter input , registers, synchronization unit and distribution unit, inverto and key groups 1.

However, this converter requires an octant detection device, which complicates the scheglles.

The closest technical solution to the present invention is a shaft rotation angle converter into a code containing transformers, whose outputs through phase detectors are connected to one switch inputs, an analog-to-digital converter including a code-to-voltage converter, a comparison unit, a register, inverters, groups keys, control unit and control unit 2.

The disadvantage of the known device is the complexity of its logical pattern, which requires the presence of a large number of elements: a decoder, several inverters, a comparison unit, phase

10 detectors, keys, code to voltage converter, etc.

The purpose of the invention is to simplify the angle-code converter circuit.

The goal is achieved

15 by the fact that in the converter of the angle of rotation of the shaft, a threshold was inserted into the code containing the rotating transformer, two switches, the control unit and the analog-to-digital converter

20 the device and the voltage shaper on diodes, the first output of which is connected through a threshold device with its first input, and the second and third outputs are connected to the measuring inputs of the analog-digital converter, the output of the rotating transformer is connected to the measuring inputs of the first and second switches, the outputs of which are connected to the second and third inlets; a diode voltage driver, respectively; a rotating transformer input and a control unit input are connected to the input terminal of the converter, the first output of the control unit is connected to the control inputs of the first switch and the analog-digital converter, and the second output is connected to the control input of the second switch, the third output the control unit and the analog-to-digital converter output are connected to the output terminals of the converter. FIG. 1 shows a block diagram of a converter; in fig. 2 the dependence of the output voltages of the rotating transformer on the measured angle. The converter contains an angle sensor, made on the basis of a rotating state transformer 1, control block 2, switches 3 and 4, diode voltage generator 5 / threshold device 6, diodes 7-11 and analog-to-digital converter (LCP) 12. Operation Let us consider the converter using the example of a rotating transformer with a three-phase output winding (selsyn) with a grounded midpoint. When the primary winding of the rotating transformer reaches a variable voltage, the absolute value is close to the maximum value and the control unit generates sequences of six and three pulses and sync pulses at the first, second and third outputs, respectively. The pulses from the first output of the control unit 2 are fed to the control input of the switch 3 and connected to its output in series the voltage Uj, Uj, C, Uj, U, U from the outputs of the rotating trans. The second output pulses of the control unit 2 provide at the output of the second switch a voltage sequence U, Uj, Uj, the connection frequency of which is two times lower than the voltage switching frequency to the output of the first switch. The voltage from the output of the second switch is used as a reference voltage for an analog-to-digital converter that generates a code from pulses U from the first output of the control unit. This allows to obtain at the output of an analog-digital converter a code proportional to the ratio of sensor voltages at the switch outputs, or overflow codes of the counter of the analog-to-digital converter, the presence and order of which in the code sequence is used to identify the area of the measured angles. The function of the threshold device is that when it arrives at its input from the output of the first or second switch through the shaper of negative voltage diodes, a positive voltage is formed at its output, the value of which is selected by selecting the parameters of the threshold device so that The first input of the ADC exceeded the maximum possible value of the voltages U, one of which is the reference. Diodes 7–9 of the diode voltage driver dissipate the ADC inputs from the shunt effect of the threshold device circuits. Diode 10 eliminates negative voltage from the switch output to the input of the ADC, providing only voltage from the output of the threshold device through diode 9. Diode 11 prevents negative voltage from entering the second ADC and maintains its operability. Thus, only in the case when the voltage at the output of the first switch is less than or equal to the voltage at the output of the second and both voltages are positive, the code at the output of the ADC is different from the overflow code, and its order in the code group from the output of the ADC is the occurrence of a sync pulse from the third output of the control unit, together with the voltage ratio code, provides an accurate angle determination. If the first after the sync pulse value of the ADC code is different from the overflow code, this means that the ratio O: and, U is satisfied, which is valid only for angles in the range (O, -). If the second codeword is different from the overflow code, then the relation 0.Uj, U, 41 is valid for the angular domain T (T). With the third codeword different from the overflow code, we have the region (T, ftf), the fourth — k, (y, z) f and that sixth — () and (i i9), respectively. The code word at the output of the converter contains a smaller number of bits than the similar code of the known device, which additionally includes bits for determining the octant. This is especially important when using multi-pole rotating transformers, where more additional bits are needed to determine the area of the measured angles. Reducing the number of bits simplifies the distribution of information over communication channels, its input into the executive

Claims (1)

Claim A converter of the angle of rotation of the shaft into a code containing a rotating transformer, two switches, a control unit and an analog-to-digital converter, characterized in that, in order to simplify the device, a threshold device and a voltage driver on the diodes are introduced into it, the first output of which connected through a threshold device to its first input, and the second and third outputs are connected to the measuring inputs of the analog-to-digital converter, the outputs of the rotating) transformer are connected to the measuring inputs of the first and second ⁵ switches, the outputs of which are connected to the second and third inputs of the voltage generator on the diodes, respectively, the input of the rotating transformer and the input of the control unit are connected to the input terminal of the converter, the first output of the control unit is connected to the control inputs of the first switch and the analog-to-digital converter, and second output Connected to the control input of the second switch, the third output of the control unit and the output of the analog-to-digital converter 15 are connected to the output terminals of the converter.