CN204115746U - A kind of multipurpose rotary transformer - Google Patents

Abstract

The utility model discloses a kind of multipurpose rotary transformer, comprise rotary transformer, revolve change decoding chip, fpga chip, Wiegand sensor, Hall element and outside NVRAM.Wiegand sensor is connected to fpga chip by mu balanced circuit in parallel and shaping circuit.Rotary transformer be connected to revolve become decoding chip be connected to fpga chip.Hall element and outside NVRAM are also all connected to fpga chip.This multipurpose rotary transformer becomes decoding chip can realize multi-turn tally function without the need to revolving of specific model, and just can realize the preservation of multi-turn information without the need to external cell, with individual pen angle value realize synchronous after export together.This multipurpose rotary transformer device structure is simple, with low cost.Further, use general FPGA to realize the synchronous and integration of angle information and multi-turn information, be not limited to asic chip, for user's independent development communication interface and agreement provide good secondary development condition, be suitable for extensive use.

Description

A kind of multipurpose rotary transformer

Technical field

The utility model belongs to angle measuring sensor technical field, particularly a kind of multipurpose rotary transformer.

Background technology

Rotary transformer (hereinafter referred to as revolving change) is the signal element that a kind of output voltage changes along with angle of rotor.In principle, it is equivalent to a rotary transformer, structure is equivalent to two-phase AC asynchronous motor.The stator winding revolving change accepts the alternating voltage excitation of certain frequency, because rotor is the Distributed Winding that two axis are mutually 90 electrical angles, can produce a pair phase 90 °, analog signals that amplitude is relevant with angle of rotor under driving voltage effect.Revolving that to become decoding chip be a kind of for realizing the special chip of rotary transformer-digital conversion, is a kind of certain moduli number converter (ADC), and its decoding principle carries out tangential method obtain angle value by detecting two-way cosine and sine signal , and the principle angle measurement adopting real-time follow-up to feed back, realize floating ground Quick Measuring and obtain angle value.The funtcional relationship between output voltage and angle of rotor pressed by rotary transformer, is mainly divided three classes: n-cosine rotary transformer, linear resolver and proportional resolver.

Revolve and become demand for multi-turn tally function can be run into during the fields such as robot, and at present on the market great majority revolve and become decoding chip and there is no this function.And fewer companies realizes multi-turn tally function as river of rubbing adopts ASIC cooperation to revolve change decoding chip more, this scheme not only cost is very high, and becomes to revolving the requirement that decoding chip has specific model.Due to specific model revolve become decoding chip cannot meet application demand in the important parameters such as resolution, therefore develop a kind of by decoding chip restriction accommodation multi-turn scheme of revolving become exigence.

Wiegand sensor is a kind of passive magnetic sensing device utilizing Wei root effect to make, and generally comprises Wei Gensi, magnetic test coil and external permanent magnets three parts.It can realize the magnetic field transition of change is electric impulse signal.Principle of work is: in alternating magnetic field, when certain polarity magnetic field being parallel to Wei Gensi reaches triggering magnetic induction density, kernel in Wei Gensi is encouraged because magnetic coercive force is weaker than shell and magnetic pole upset is occurred, direction of magnetization transfers the same direction with shell instantaneously to, also there is instantaneous variation in Wei Gensi surrounding space magnetic field simultaneously, in magnetic test coil, generate an electric pulse thus.If after this this field weakening, maintenance is stablized constant by the direction of magnetization of kernel, and magnetic test coil also exports without electric pulse; But when opposite polarity magnetic field is strengthened to triggering magnetic induction density, Wei Gensi kernel direction of magnetization overturns again instantaneously, and generates the contrary electric pulse in a direction in magnetic test coil.

The ProASIC3 family device that Actel company releases just has become the first-selected FPGA(field programmable gate array of high-performance portable equipment since asking city) chip, be characterized in low-power consumption, power on namely run and security high.From the SRAM(static RAM that traditional F PGA adopts) technology is different, ProASIC3 series adopts Flash LVCMOS(need provide corresponding Chinese terminology) technique, power on without the need to load logic, and with security mechanism can prevent all programming informations of outer bound pair from conducting interviews.In addition, ProASIC3 Series FPGA has very little chip volume and being enough to match in excellence or beauty the price of ASIC, is applicable to very much the sensors such as scrambler and uses.

Utility model content

Problem to be solved in the utility model is to provide a kind of multipurpose rotary transformer, and this revolves to become and becomes decoding chip can realize multi-turn tally function without the need to revolving of specific model, and just can realize the preservation of multi-turn information without the need to external cell.

A kind of multipurpose rotary transformer disclosed in the utility model, comprise rotary transformer, revolve change decoding chip, fpga chip (FPGA:Field-Programmable Gate Array, i.e. field programmable gate array), Wiegand sensor, Wiegand sensor is connected to fpga chip, rotary transformer be connected to revolve become decoding chip be connected to fpga chip.Rotary transformer is used for the rotational angle θ of motor shaft to be converted to two-way sine and cosine voltage analog Sine and Cosine; Revolving change decoding chip, for generation of making to revolve the pumping signal of exchanging work and doing, and calculating the current angle value of motor shaft by cosine and sine signal; Wiegand sensor, responds to the pulse of generation generating positive and negative voltage, powers and provide the number of turns and directional information for subsequent conditioning circuit in rotating at motor shaft; Fpga chip, the synchronization bit of the real-time angular value sent for receipt decoding chip and the expression number of turns with Hall element transmission, and jointly determine final lap information in conjunction with the positive negative direction of Wei root inductive impulse, both are integrated and is outwards exported by interface circuit.

As the further improvement of technique scheme, described multipurpose rotary transformer also comprises Hall element and outside NVRAM(nonvolatile memory), described Hall element and outside NVRAM are all connected to fpga chip.Hall element coordinates FPGA to realize the synchronizing function of lap information and individual pen angle θ by the change in testing magnetic field; NVRAM chip, for being preserved when the number of turns changes, does not lose during system power failure.

Another kind as technique scheme improves, and also arranges mu balanced circuit in parallel and shaping circuit between described Wiegand sensor and fpga chip.Mu balanced circuit, for giving rear class chip power supply by Wiegand sensor inductive impulse after voltage stabilizing; Shaping circuit, for eliminating the clutter of induced voltage pulse, make fpga chip judge direction and Counts more reliable.

As the further improvement of technique scheme, described Wiegand sensor, Hall element are all connected to the I/O mouth of fpga chip; NVRAM is connected with fpga chip by SPI mouth; Parallel I/O mouth is utilized to connect between fpga chip and rotation decoding chip.

Multipurpose rotary transformer of the present utility model solves current rotary transformer preservation multi-turn information to be needed to use specific problem of revolving change decoding chip, the angle that rotary transformer is turned over sentence to meter circle, preserve multi-turn information, with individual pen angle value realize synchronous after export together.This multipurpose rotary transformer device structure is simple, with low cost, revolves change decoding chip without the need to what use specific model.Use general FPGA to realize the synchronous and integration of angle information and multi-turn information, be not limited to and specifically revolve change decoding chip, for user's independent development communication interface and agreement provide good secondary development condition, be suitable for extensive use.

Accompanying drawing explanation

Fig. 1 is the utility model multipurpose rotary transformer functional structure chart;

Fig. 2 is Wiegand sensor forward sense timing chart;

Fig. 3 is the synchronous process schematic diagram of individual pen and multi-turn information.

Embodiment

Below in conjunction with accompanying drawing, a kind of multipurpose rotary transformer that the utility model proposes is described in detail.

As shown in Figure 1, a kind of multipurpose rotary transformer disclosed in the utility model, comprises rotary transformer, revolves change decoding chip, fpga chip, Wiegand sensor, Hall element and outside NVRAM.Wiegand sensor is connected to power supply and the exterior I/O mouth of fpga chip, also arranges mu balanced circuit in parallel and shaping circuit between Wiegand sensor and fpga chip.Rotary transformer is connected to the excitation and cosine and sine signal input interface of revolving and becoming decoding chip, revolves exterior I/O mouth that the parallel output mouth becoming decoding chip is connected to fpga chip.Hall element and outside NVRAM are connected respectively to the I/O mouth of fpga chip and extend out SPI mouth.

Described rotary transformer can select sine and cosine resolver, linear resolver and proportional resolver, preferred sine and cosine resolver, adopts the TS2620N21E11 model of TAMAGAWA company.Revolve change decoding chip, adopt 16 R/D conversion chip AD2S1210 of ADI company or AU6802, AU6805 of Duo Mo river company.FPGA selects ProASIC3 series A 3P250 model or the AGLxxx series of Actel company.Wiegand sensor, issue magnetisation upset effect in alternating magnetic field (motor shaft being fixed the cylinder magnet steel of a radial magnetizing) effect, revolve turn around generation positive pulse or negative pulse, relevant with motor shaft rotation direction, pulse height is greater than 5V, pulsewidth 30us.Mu balanced circuit, utilizes the linear stabilized power supply of low voltage difference, low noise to convert Wei root induced voltage to 3.3V DC level, is FPGA and nonvolatile external memory (NVRAM) power supply; The FPGA number of turns of falling into a trap is 0 ~ 65535, adds 1 circle counterclockwise, subtracts 1 circle clockwise, cycle count.Shaping circuit, uses Schmidt trigger composition, for eliminating the clutter of induced voltage pulse, improves antijamming capability, makes FPGA count circle and judge that direction is more reliable.Hall element, is made up of the Hall element of four phase bits that stagger, and coordinates FPGA to realize the synchronizing function of lap information and individual pen angle θ by the change in testing magnetic field; Hall element is the integrated chip iC-MZ etc. of SS30AT and the iC-Haus company of Honeywell company.

This multipurpose rotary transformer, external interface circuit take RS422/485 as Physical layer, can the common protocol such as compatible BISS and Endat2.1/2.2.

The pulse signal that this multipurpose rotary transformer utilizes Wiegand sensor to respond to is through mu balanced circuit for FPGA powers, and the I/O mouth simultaneously passing to FPGA through shaping circuit carries out counting and judging.The motor shaft position signal sensed is passed to the I/O mouth of FPGA by Hall element, coordinates FPGA to complete the synchronous correction function of meter circle.NVRAM is powered by above-mentioned mu balanced circuit equally, is connected with FPGA by SPI mouth, for preserving lap information.Utilize Parallel I/O mouth to carry out data communication between FPGA and rotation decoding chip, within a fixed cycle, complete the acquisition of multi-turn counting and individual pen position, and integrated out, export finally by RS422/485 interface circuit.

Multipurpose rotary transformer principle of the present utility model mainly utilizes the Wei root effect of special magnetic material realize sentencing to meter circle, and to power for peripheral chip, just can realize the preservation of multi-turn information without the need to external cell.Hall element coordinates FPGA to realize the synchronous of individual pen angle value and multi-turn information, and they integrate and export with certain agreement the most at last.Specific works principle is:

When electric machine rotation followed by sine and cosine resolver, be attached to single magnet steel to pole radial magnetizing on motor shaft with rotation formation and modification magnetic field.Wiegand sensor senses variation magnetic field, in electric machine rotation one week, produce a potential pulse.As shown in Figure 2, when motor shaft is rotated counterclockwise, potential pulse is that just width is 30us, and amplitude is 7V.When motor rotates clockwise, amplitude and pulsewidth remain unchanged, and just voltage direction is contrary.

Mu balanced circuit uses LM3480 low pressure difference linearity voltage stabilizing chip pulse voltage to be converted into 3.3V DC voltage, for FPGA, NVRAM and Hall element are powered.Shaping circuit filtering clutter disturbs, and makes potential pulse become the square-wave signal of standard.

Hall element is made up of four Hall elements of certain PHASE DISTRIBUTION that staggers, in motor rotary course, sense the change in magnetic field, produce the sinusoidal curve having fixed skew for a pair, enter FPGA by voltage comparator, as shown in Figure 3, FPGA obtains the synchrodata of 2 after treatment.In Fig. 3, ST represents individual pen angle value, and MT is multi-revolution data value, and all represent with 2 systems, MSB represents most significant digit, and LSB is lowest order.The MT LSB-2 of Hall element and MT LSB-1 is 2 bit synchronization positions.Due to the existence of synchronization bit, individual pen most significant digit is (corresponding ST MSB one-period) when generation 360 ° changes, and the value of multi-turn lowest order MT LSB becomes 0 from 1, or becomes 1 from 0, realizes tally function, and 2 bit synchronization potential energies enough obtain ± synchronization interval of 90 °.

Above-mentioned data synchronization process realizes in FPGA, and multi-turn figure place is 16.Individual pen becomes decoding chip decision by revolving, and is also 16.Both combine by FPGA, export in serial RS422/485 mode, and agreement can by User Exploitation or customization, and comparatively conventional has BISS and Endat2.1/2.2 etc., also can directly export with serial protocols such as SPI.

Claims (4)

1. a multipurpose rotary transformer, comprise rotary transformer, revolve change decoding chip, it is characterized in that: also comprise Wiegand sensor and fpga chip, Wiegand sensor is connected to fpga chip, rotary transformer be connected to revolve become decoding chip be connected to fpga chip.

2. multipurpose rotary transformer according to claim 1, is characterized in that: described multipurpose rotary transformer also comprises Hall element and outside NVRAM, and described Hall element and outside NVRAM are all connected to fpga chip.

3. multipurpose rotary transformer according to claim 1, is characterized in that: also arrange mu balanced circuit in parallel and shaping circuit between described Wiegand sensor and fpga chip.

4. the multipurpose rotary transformer according to claim 1,2 or 3, is characterized in that: described Wiegand sensor, Hall element are all connected to the I/O mouth of fpga chip; NVRAM is connected with fpga chip by SPI mouth; Parallel I/O mouth is utilized to connect between fpga chip and rotation decoding chip.