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Details, datasheet, quote on part number:AD2S105
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FEATURES Current Conditioning Complete Vector Transformation on Silicon Three-Phase 120° and Orthogonal 90° Signal Transformation Three-Phase Balance DiagnosticHomopolar Output DQ Manipulation Real-Time Filtering APPLICATIONS AC Induction Motor Control Spindle Drive Control Pump Drive Control Compressor Drive Control and Diagnostics Harmonic Measurement Frequency Analysis Three-Phase Power Measurement
Cos Sin Cos Cos ( + 120 °) Cos ( + 240 °) Sin IS1 IS2 3-2 IS3 Vqs Vds
Three-Phase Current Conditioner AD2S105
FUNCTIONAL BLOCK DIAGRAM
INPUT DATA STROBE POSITION PARALLEL DATA 12 BITS BUSY
SECTOR MULTIPLIER
SINE AND COSINE MULTIPLIER
Cos + Vds'
SECTOR MULTIPLIER
SINE AND COSINE MULTIPLIER
Vqs' Sin +
CONV1 CONV2
DECODE
Ia + Ib + Ic 3 HOMOPOLAR REFERENCE +5V GND 5V
HOMOPOLAR OUTPUT
GENERAL DESCRIPTION
A two-phase rotated output facilitates the implementation of multiple rotation blocks. The AD2S105 is fabricated on LC2MOS and operates on ± 5 volt power supplies.
PRODUCT HIGHLIGHTS
The AD2S105 performs the vector rotation of three-phase 120 degree or two-phase 90 degree sine and cosine signals by transferring these inputs into a new reference frame which is controlled by the digital input angle . Two transforms are included in the AD2S105. The first is the Clarke transform which computes the sine and cosine orthogonal components of a three-phase input. These signals represent real and imaginary components which then form the input to the Park transform. The Park transform relates the angle of the input signals to a reference frame controlled by the digital input port. The digital input port on the AD2S105 is a 12-bit/parallel natural binary port. If the input signals are represented by Vds and Vqs, respectively, where Vds and Vqs are the real and imaginary components, then the transformation can be described as follows: Vds' = Vds Cos Vqs Sin Vqs' = Vds Sin + Vqs Cos Where Vds' and Vqs' are the output of the Park transform and Sin, and Cos are the trigonometric values internally calculated by the AD2S105 from the binary digital data . The input section of the device can be configured to accept either three-phase inputs, two-phase inputs of a three-phase system, or two 90 degree input signals. The homopolar output indicates an imbalance of a three-phase input only at a userspecified level. The digital input section will accept a resolution of up to 12 bits. An input data strobe signal is required to synchronize the position data and load this information into the device counters. REV. 0
Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Current Conditioning The AD2S105 transforms the analog stator current signals (Is1, Is2, Is3) using the digital angular signal (reference frame) into dc values which represent direct current (Ids) and quadrature current (Iqs). This transformation of the ac signals into dc values simplifies the design of the analog-to-digital (A/D) conversion scheme. The A/D conversion scheme is simplified as the bandwidth sampling issues inherent in ac signal processing are avoided and in most drive designs, simultaneous sampling of the stator currents may not be necessary.
Hardware Peripheral for Standard Microcontroller and DSP Systems
The AD2S105 off-loads the time consuming Cartesian transformations from digital processors and benchmarks show a significant speed improvement over single processor designs. AD2S105 transformation time = 2 µs.
Field Oriented Control of AC Motors
The AD2S105 accommodates all the necessary functions to provide a hardware solution for current conditioning in variable speed control of ac synchronous and asynchronous motors.
Three-Phase Imbalance Detection
The AD2S105 can be used to sense imbalances in a three-phase system via the homopolar output.
One Technology Way, P.O. Box 9106, Norwood. MA 02062-9106, U.S.A. Tel: 617/329-4700 Fax: 617/326-8703
AD2S105SPECIFICATIONS T = 40°C to +85°C, unless otherwise noted)
A
(VDD = +5 V ± 5%; VSS = 5 V ± 5% AGND = DGND = O V;
Typ ± 2.8 Max ± 3.3 ± 4.25 Units V p-p V p-p k k M 1.05 Conditions DC to 50 kHz DC to 50 kHz
Parameter SIGNAL INPUTS PH/IP1, 2, 3, 4 Voltage Level PH/IPH1, 2, 3 Voltage Level Input Impedance PH/IP1, 2, 3 PH/IPH1, 2, 3 PH/IP1, 4 Gain PH/IP1, 2, 3, 4 PH/IPH1, 2, 3 VECTOR PERFORMANCE 3-Phase Input-Output Radius Error (Any Phase) Angular Error1, 2 PH/IP PH/IPH Differential Nonlinearity Full Power Bandwidth Small Signal Bandwidth ANALOG SIGNAL OUTPUTS PH/OP1, 4 Output Voltage3 Offset Voltage Slew Rate Small Signal Step Response Output Impedance Output Drive Current Resistive Load Capacitive Load STROBE Write Max Update Rate BUSY Pulse Width V OH V OL DIGITAL INPUTS DB1DB12 V IH V IL Input Current, IIN Input Capacitance, CIN CONV MODE (CONV1, CONV2) V IH V IL Input Current Input Capacitance
Min
7.5 13.5
10 18 1
Mode 1 Only (2 Phase) Sin & Cos
0.95
1 0.56
± 0.4 15
±1 30 30 ±1
% arc min arc min LSB kHz kHz
DC to 600 Hz DC to 600 Hz DC to 600 Hz
50 200
± 2.8 2 2 1 15 4.0 50 100 366 1.7 4
± 3.3 10
V p-p mV V/µs µs mA k pF ns kHz
PH/IP, PH/IPH INPUTS DC to 50 kHz Inputs = 0 V 1° Input to Settle to ± 1 LSB (Input to Output) Outputs to AGND
3.0 2
Positive Pulse
2.5 1
µs V dc V dc
Conversion in Process IOH = 0.5 mA IOL = 0.5 mA
3.5 1.5 ± 10 10
V dc V dc µA pF
3.5 1.5 100 10
V dc V dc µA pF
Internal 50 k Pull-Up Resistor
2
REV. 0
AD2S105
Parameter HOMOPOLAR OUTPUT HPOPOUTPUT V OH V OL HPREFREFERENCE POWER SUPPLY V DD V SS IDD ISS Min Typ Max Units Conditions
4 1 0.5
V dc V dc V dc
IOH = 0.5 mA IOL = 0.5 mA Homopolar Output-Internal ISOURCE = 25 µA and 20 k to AGND
4.75 5.25
5 5 4 4
5.25 4.75 10 10
V dc V dc mA mA
Quiescent Current Quiescent Current
NOTES 1 Angular accuracy includes offset and gain errors, measured with a stationary digital input and maximum analog frequency inputs. 2 The angular error does not include the additional error caused by the phase delay as a function of input frequency. For example, if f INPUT = 600 Hz, the contribution to the error due to phase delay is: 650 ns × fINPUT × 60 × 360 = 8.4 arc minutes. 3 Output subject to input voltage and gain. Specifications subject to change without notice.
Power Supply Voltage (+VDD, VSS) . . . . . . . . . ± 5 V dc ± 5% Analog Input Voltage (PH/IP1, 2, 3, 4) . . . . . . 2 V rms ± 10% Analog Input Voltage (PH/IPH1, 2, 3) . . . . . . 3 V rms ± 10% Ambient Operating Temperature Range Industrial (AP) . . . . . . . . . . . . . . . . . . . . . . . 40°C to +85°C
ABSOLUTE MAXIMUM RATINGS (TA = +25°C)
RECOMMENDED OPERATING CONDITIONS
ORDERING GUIDE
Model AD2S105AP
Temperature Range 40°C to +85°C
Accuracy 30 arc min
Option* P-44A
*P = Plastic Leaded Chip Carrier.
VDD to AGND . . . . . . . . . . . . . . . . . . . . . . . 0.3 V to +7 V dc VSS to AGND . . . . . . . . . . . . . . . . . . . . . . . +0.3 V to 7 V dc AGND to DGND . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 0.3 V dc Analog Input Voltage to AGND . . . . . . . . . . . . . . . VSS to VDD Digital Input Voltage to DGND . . . . 0.3 V to VDD + 0.3 V dc Digital Output Voltage to DGND . . . . . . 0.3 V to VDD + V dc Analog Output Voltage to AGND . . . . . . . . . . . . . . . . . . . . . . VSS 0.3 V to VDD + 0.3 V dc Analog Output Load Condition (PH/OP1, 4 Sin, Cos) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 k Power Dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140 mW Operating Temperature Industrial (AP) . . . . . . . . . . . . . . . . . . . . . . . 40°C to +85°C Storage Temperature . . . . . . . . . . . . . . . . . 65°C to +150°C Lead Temperature (Soldering, 10 sec) . . . . . . . . . . . . . +300°C
CAUTION
1. Absolute Maximum Ratings are those values beyond which damage to the device will occur. 2. Correct polarity voltages must be maintained on the +VDD and VSS pins
CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD2S105 features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality.
WARNING!
ESD SENSITIVE DEVICE
REV. 0
3
AD2S105
PIN DESIGNATIONS1, 2, 3
PH/OP4
PIN CONFIGURATION
STROBE DGND BUSY
Pin 3 4 5 6 7 10 11 12 13 14 15 16 17 19 20 21 22 23 24 25 26 2738 41 42 44
Mnemonic STROBE V DD V SS PH/OP4 PH/OP1 AGND PH/IP4 PH/IPH3 PH/IP3 PH/IPH2 PH/IP2 PH/IPH1 PH/IP1 V SS HPREF HPOP HPFILT CONV1 CONV2 COS SIN DB12 to DB1 V DD DGND BUSY
Description Begin Conversion Positive Power Supply Negative Power Supply Sin ( + ) Cos ( + ) Analog Ground Sin Input High Level Cos ( + 240°) Input Cos ( + 240°) Input High Level Cos ( + 120°) Input Cos ( + 120°) Input High Level Cos Input Cos () Input Negative Power Supply Homopolar Reference Homopolar Output Homopolar Filter Select Analog Input Format Select Analog Input Format Cos Output Sin Output (DB1 = MSB, DB12 = LSB Parallel Input Data) Positive Power Supply Digital Ground Internal Logic Setup Time
VDD
VDD
41
VSS
NC
6
5
4
3
2
NC
1
44
43
NC
42
40
PH/OP1 NC NC AGND PH/IP4 PH/IPH3 PH/IP3 PH/IPH2 PH/IP2 PH/IPH1 PH/IP1
7 8 9 10 11 12 13 14 15 16 17
NC
39 NC 38 DB1 37 DB2 36 DB3
AD2S105
TOP VIEW (NOT TO SCALE)
35 DB4 34 DB5 33 DB6 32 DB7 31 DB8 30 DB9 29 DB10
18
19
20
21
22
23
24
25
26
27
28
CONV1
HPFILT
CONV2
HPOP
NC = NO CONNECT.
NOTES 1 90° orthogonal signals = Sin , Cos (Resolver) = PH/IP4 and PH/IP1. 2 Three phase, 120°, three-wire signals = Cos , Cos ( + 120°), Cos ( + 240°). = PH/IP1, PH/IP2, PH/IP3 High Level = PH/IPH1, PH/IPH2, PH/IPH3. 3 Three Phase, 120°, two-wire signals = Cos ( + 120°), Cos ( + 240°) = PH/IP2, PH/IP3. In all cases where any of the input Pins 11 through 17 are not used, they must be left unconnected.
HPREF
DB12
DB11
COS
VSS
SIN
NC
4
REV. 0
AD2S105
THEORY OF OPERATION
A fundamental requirement for high quality induction motor drives is that the magnitude and position of the rotating air-gap rotor flux be known. This is normally carried out by measuring the rotor position via a position sensor and establishing a rotor oriented reference frame. To generate a flux component in the rotor, stator current is applied. A build-up of rotor flux is concluded which must be maintained by controlling the stator current, ids, parallel to the rotor flux. The rotor flux current component is the magnetizing current, imr. Torque is generated by applying a current component which is perpendicular to the magnetizing current. This current is normally called the torque generating current, iqs. To orient and control both the torque and flux stator current vectors, a coordinate transformation is carried out to establish a new reference frame related to the rotor. This complex calculation is carried out by the AD2S105. To expand upon the vector operator a description of a single vector rotation is of assistance. If it is considered that the moduli of a vector is OP and that through the movement of rotor position by , we require the new position of this vector it can be deduced as follows: Let original vector OP = A (Cos + jSIN ) where A is a constant; if OQ = OP ej and: ej = CosO + jSin Q = A (Cos ( + ) + jSin ( + )) = A [Cos Cos Sin Sin + jSin Cos + jCos = A [(Cos + jSin ) (Cos + jSin )]
a Q + d O P
To relate these stator current to the reference frame the rotor currents assume the same rectangular coordinates, but are now rotated by the operator ej , where ej = Cos + jSin . Here the term vector rotator comes into play where the stator current vector can be represented in rotor-based coordinates or vice versa. The AD2S105 uses ej as the core operator. In terms of the mathematical function, it rotates the orthogonal ids and iqs components as follows:
w
ids' + jiqs' = (Ids + jIqs) ej here ids', iqs' = stator currents in the rotor reference frame. And = ej = Cos + jSin + jSin ) (Ids + jIqs)(Cos iids' = Ids Cos
The output from the AD2S105 takes the form of: Iqs Sin + Iqs Cos T
qs' = Ids Sin
he matrix equation is:
[][
i d s' iqs' =
Cos Sin
Sin Cos
]
[]
I ds Iqs
(
1)
and it is shown in Figure 2.
Sin ] (2)
Ids e Iqs
j
Ids' Iqs'
Figure 2. AD2S105 Vector Rotation Operation
INPUT CLARK COS COS + 120° COS + 240° SIN
3 TO 2 TRANSFORMATION
Figure 1. Vector Rotation in Polar Coordinate
LATCH
The complex stator current vector can be represented as is = ias + aibs + a2ics where a = e
SINE AND COSINE MULTIPLIER (DAC)
COS ( + )
j 2 j 4 and a2 = e . This can be re3 3 placed by rectangular coordinates as
is = ids + jiqs (3)
DIGITAL
LATCH
LATCH
SINE AND COSINE MULTIPLIER (DAC)
SIN ( + )
In this equation ids and iqs represent the equivalent of a twophase stator winding which establishes the same magnitude of MMF in a three-phase system. These inputs can be seen after the three-phase to two-phase transformation in the AD2S105 block diagram. Equation (3) therefore represents a three-phase to two-phase conversion.
PARK
Figure 3. Converter Operation Diagram
REV. 0
5
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