Hall Speed and Position

Library:
Motor Control Blockset / Sensor Decoders

Ports

Input

`HallVal` — Current Hall sensor output state
scalar

The Hall state at current time. For example, these are the possible valid Hall states (where the MSB represents the output of the first Hall sensor connected):

5 - (101)
4 - (100)
6 - (110)
2 - (010)
3 - (011)
1 - (001)

Data Types: single | double | fixed point

`Cnt` — External counter value
scalar

The external counter value that the block uses to determine the time elapsed between the Hall state change and block execution.

Data Types: single | double | fixed point

`SpdCnt` — Count at Hall state change
scalar

This value indicates the clock cycles (time) elapsed between two consecutive changes in the Hall state.

Data Types: single | double | fixed point

`Dir` — Rotor spin direction during current Hall state
scalar

The direction of the rotor spin (either +1 or –1 indicating positive or negative direction of rotation, respectively) during the current Hall state.

Data Types: single | double | fixed point

`SpdVal` — Validity of current and previous Hall states and speed calculation
scalar

The port value indicates Hall state validity. The value zero indicates that the current or previous Hall state is invalid and that the block cannot calculate speed and position.

The value one indicates that both the current and previous Hall states are valid and that the block can calculate speed and position.

Data Types: single | double | fixed point

`HallChng` — Value of Hall state change flag
scalar

The port value indicates Hall state change and block execution status. The value one indicates that the Hall state changed, but that the block execution is pending. The value zero indicates that the block has completed executing the last Hall state change.

Data Types: single | double | fixed point

Output

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`θ_e` — Electrical position of rotor
scalar

The estimated electrical position of the rotor based on the Expected hall sequence in positive direction parameter and the Direction, HallVal, and CounterValue inputs.

Dependencies

To enable this port, set Block output to either Position or Speed and position.

Data Types: single | double | fixed point

`⍵_m` — Mechanical speed of rotor
scalar

The mechanical speed of the rotor in revolutions per minute. The block calculates this value by tracking the Hall state changes.

The port returns zero if the SpdVal input is zero.

Dependencies

To enable this port, set Block output to either Speed or Speed and position.

Data Types: single | double | fixed point

`HallChngRst` — Resets Hall state change flag to zero
scalar

The port outputs a value of zero (sets the Hall state change flag to zero) indicating that the block has successfully executed speed and position computations for the last Hall state change.

Data Types: single | double | fixed point

Parameters

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General

`Block output` — Select output ports
`Speed and position` (default) | `Speed` | `Position`

Select the available block output ports as one of the following values:

Speed and position
Speed
Position

`Counter size` — Size of external counter register
`16 bits` (default) | `8 bits` | `32 bits`

The register size of the external counter. The maximum counter value is $2^{n} -1$ , where $n$ = counter size.

`Counter clock frequency (Hz)` — Clock frequency of external counter
`90e6` (default) | scalar

The clock frequency of the external counter.

`Block sample time (S)` — Sample time after which block executes again
`50e-6` (default) | scalar

The time between two consecutive instances of block execution.

`Number of pole pairs` — Number of pole pairs available in motor
`8` (default) | scalar

Number of pole pairs available in the motor.

`Minimum detectable speed (RPM)` — Minimum speed that block can detect
`20` (default) | scalar

The block does not calculate position for speed below this value.

`Speed measurement interval` — Interval over which block measures speed
`Every 180 Degrees` (default) | `Every 60 Degrees`

Rotor angular displacement that represents the interval at which the SpdCnt port value was calculated.

`Speed unit` — Unit of rotor angular speed output
`Radians/sec` (default) | `Degrees/sec` | `RPM` | `Per unit`

Unit of the angular velocity or mechanical speed (⍵_m) output.

Dependencies

To enable this parameter, set Block output to either Speed or Speed and position.

`Speed datatype` — Data type of rotor angular speed output
`single` (default) | `double` | `fixdt(1,16,0)` | `fixdt(1,16,2^0,0)` | `<data type expression>`

Data type of the rotor angular speed output.

Dependencies

To enable this parameter, set Block output to either Speed or Speed and position.

Position

`Expected hall sequence in positive direction` — Sequence indicating positive direction
`ABC` (default) | `CBA` | `Custom sequence`

The Hall sensor sequence that represents the positive direction of rotor spin.

Dependencies

To enable this parameter, set Block output to either Position or Speed and position.

`Sequence` — Custom sequence indicating positive direction
`[5,4,6,2,3,1]` (default) | scalar

The custom sequence that you can enter to represent rotor spin in the positive direction.

Dependencies

To enable this parameter:

Set Block output to either Position or Speed and position.
Set Expected hall sequence in positive direction to Custom sequence.

`Order of extrapolation of position` — Indicates precision in position computation
`1st Order` (default) | `2nd Order`

The 1st Order option is less accurate in computing position, but quick. The 2nd Order option is more accurate, but needs more computation time. These equations describe the options:

$θ_{1 s t O r d e r} = θ_{s e c t o r} + ω t$

$θ_{2 n d O r d e r} = θ_{s e c t o r} + ω t + \frac{1}{2} α t^{2}$

where:

$θ_{1 s t O r d e r}$ = Position computed by using 1st order extrapolation.

$θ_{2 n d O r d e r}$ = Position computed by using 2nd order extrapolation.

$θ_{s e c t o r}$ = Sector angle defined by the Hall sensor output.

$ω$ = Angular velocity of the rotor.

$α$ = Angular acceleration of the rotor.

$t$ = Time spent in a sector.

Dependencies

To enable this parameter, set Block output to either Position or Speed and position.

`Position unit` — Unit of angular speed output
`Radians` (default) | `Degrees` | `Per unit`

Unit of angular speed output.

Dependencies

To enable this parameter, set Block output to either Position or Speed and position.

`Position datatype` — Data type of angular speed output
`single` (default) | `double` | `fixdt(1,16,0)` | `fixdt(1,16,2^0,0)` | `<data type expression>`

Data type of angular speed output.

Dependencies

To enable this parameter, set Block output to either Position or Speed and position.

Model Examples

Hall Offset Calibration for PMSM Motor

Calculates the offset between the rotor direct axis (d-axis) and position detected by the Hall sensor. The field-oriented control (FOC) algorithm needs this position offset to run the permanent magnet synchronous motor (PMSM) correctly. To compute the offset, the target model runs the motor in the open-loop condition. The model uses a constant ${V_d}$ (voltage along the stator's d-axis) and a zero ${V_q}$ (voltage along the stator's q-axis) to run the motor (at a low constant speed) by using a position or ramp generator. When the position or ramp value reaches zero, the corresponding rotor position is the offset value for the Hall sensors.

Field-Oriented Control of PMSM by Using Hall Sensor

Implements the field-oriented control (FOC) technique to control the speed of a three-phase permanent magnet synchronous motor (PMSM). The FOC algorithm requires rotor position feedback, which is obtained by a Hall sensor. For details about FOC, see Field-Oriented Control (FOC).

Documentation

Hall Speed and Position

Description

Ports

Input

HallVal — Current Hall sensor output state scalar

Cnt — External counter value scalar

SpdCnt — Count at Hall state change scalar

Dir — Rotor spin direction during current Hall state scalar

SpdVal — Validity of current and previous Hall states and speed calculation scalar

HallChng — Value of Hall state change flag scalar

Output

θe — Electrical position of rotor scalar

Dependencies

⍵m — Mechanical speed of rotor scalar

Dependencies

HallChngRst — Resets Hall state change flag to zero scalar

Parameters

General

Block output — Select output ports Speed and position (default) | Speed | Position

Counter size — Size of external counter register 16 bits (default) | 8 bits | 32 bits

Counter clock frequency (Hz) — Clock frequency of external counter 90e6 (default) | scalar

Block sample time (S) — Sample time after which block executes again 50e-6 (default) | scalar

Number of pole pairs — Number of pole pairs available in motor 8 (default) | scalar

Minimum detectable speed (RPM) — Minimum speed that block can detect 20 (default) | scalar

Speed measurement interval — Interval over which block measures speed Every 180 Degrees (default) | Every 60 Degrees

Speed unit — Unit of rotor angular speed output Radians/sec (default) | Degrees/sec | RPM | Per unit

Dependencies

Speed datatype — Data type of rotor angular speed output single (default) | double | fixdt(1,16,0) | fixdt(1,16,2^0,0) | <data type expression>

Dependencies

Position

Expected hall sequence in positive direction — Sequence indicating positive direction ABC (default) | CBA | Custom sequence

Dependencies

Sequence — Custom sequence indicating positive direction [5,4,6,2,3,1] (default) | scalar

Dependencies

Order of extrapolation of position — Indicates precision in position computation 1st Order (default) | 2nd Order

Dependencies

Position unit — Unit of angular speed output Radians (default) | Degrees | Per unit

Dependencies

Position datatype — Data type of angular speed output single (default) | double | fixdt(1,16,0) | fixdt(1,16,2^0,0) | <data type expression>

Dependencies

Model Examples

Hall Offset Calibration for PMSM Motor

Field-Oriented Control of PMSM by Using Hall Sensor

Extended Capabilities

C/C++ Code Generation Generate C and C++ code using Simulink® Coder™.

Fixed-Point Conversion Design and simulate fixed-point systems using Fixed-Point Designer™.

See Also

Topics

Motor Control Blockset Documentation

Support

`HallVal` — Current Hall sensor output state
scalar

`Cnt` — External counter value
scalar

`SpdCnt` — Count at Hall state change
scalar

`Dir` — Rotor spin direction during current Hall state
scalar

`SpdVal` — Validity of current and previous Hall states and speed calculation
scalar

`HallChng` — Value of Hall state change flag
scalar

`θ_e` — Electrical position of rotor
scalar

`⍵_m` — Mechanical speed of rotor
scalar

`HallChngRst` — Resets Hall state change flag to zero
scalar

`Block output` — Select output ports
`Speed and position` (default) | `Speed` | `Position`

`Counter size` — Size of external counter register
`16 bits` (default) | `8 bits` | `32 bits`

`Counter clock frequency (Hz)` — Clock frequency of external counter
`90e6` (default) | scalar

`Block sample time (S)` — Sample time after which block executes again
`50e-6` (default) | scalar

`Number of pole pairs` — Number of pole pairs available in motor
`8` (default) | scalar

`Minimum detectable speed (RPM)` — Minimum speed that block can detect
`20` (default) | scalar

`Speed measurement interval` — Interval over which block measures speed
`Every 180 Degrees` (default) | `Every 60 Degrees`

`Speed unit` — Unit of rotor angular speed output
`Radians/sec` (default) | `Degrees/sec` | `RPM` | `Per unit`

`Speed datatype` — Data type of rotor angular speed output
`single` (default) | `double` | `fixdt(1,16,0)` | `fixdt(1,16,2^0,0)` | `<data type expression>`

`Expected hall sequence in positive direction` — Sequence indicating positive direction
`ABC` (default) | `CBA` | `Custom sequence`

`Sequence` — Custom sequence indicating positive direction
`[5,4,6,2,3,1]` (default) | scalar

`Order of extrapolation of position` — Indicates precision in position computation
`1st Order` (default) | `2nd Order`

`Position unit` — Unit of angular speed output
`Radians` (default) | `Degrees` | `Per unit`

`Position datatype` — Data type of angular speed output
`single` (default) | `double` | `fixdt(1,16,0)` | `fixdt(1,16,2^0,0)` | `<data type expression>`

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Fixed-Point Conversion
Design and simulate fixed-point systems using Fixed-Point Designer™.