motor-foc-ltid-pmsm — PMSM FOC + Load-Torque Estimator + Feed-Forward Builder
Three-phase 2-level voltage-source inverter + PMSM. Field-oriented speed control (outer Symmetric-Optimum speed PI → iq_ref; inner dq current PI ×2 with cross-coupling + back-EMF decoupling feed-forward; id_ref = 0), augmented with a linear load-torque state estimator on the model x = [ω_m; T_L], u = T_e, y = ω_m — seven selectable realizations on one shared structure (pole-placed Luenberger, steady-state KF, steady colored KF, recursive KF, recursive colored KF, correlated-noise KF, continuous Kalman-Bucy). The estimate T̂_L is fed forward into iq_ref (via the torque constant) to cut the load-step speed dip the speed PI alone cannot. v1 baseline supports SPMSM and mild-saliency IPMSM (Lq/Ld < 2, id_ref = 0); strong-saliency MTPA deferred.
Layered on motor-pmsm-base. All base discipline applies (plant build standard, dq conventions, building-blocks SOP, broken-FOC defense, visual 4-check).
⚠️ Estimator validation note
The base FOC plant + dq current PI + speed PI formulas are reused by pointer from the base pmsm_formulas.md §0–§7, §A. The load-torque estimator family (F2–F10: augmented model, observability, Luenberger, recursive/steady/colored/correlated KF, Kalman-Bucy) is documented in formulas/pmsm_foc_ltid_formulas.md, each formula cross-checked against ≥2 independent academic sources (see base/theory_anchor.md).
Validation requirement: a visual review on the MATLAB desktop (motor rotates / iq tracks / iabc AC sinusoidal / Te energy balance) plus the FF-on-vs-FF-off dip-reduction demonstration. Neither can be skipped.
Must-Follow Rules
- Plan first — numbered plan with the input table (below), the design-decision choices (discretization path, KF tuning, plant choice — see the build template's parameter block), and the build-script structure. Get user approval before the first
add_block.
- One-click reproducibility — every numeric originates in the model
InitFcn (machine, PI gains, all estimator matrices via c2d/place/dlqe, the augmented n=3 colored model, the F9.a cross-term, the F10 continuous intensities, plus guarded ff_enable/est_sel/plant_sel defaults). No external design script may need to run first. See base one-click discipline.
- The six structural modules are non-negotiable — (1) plant exposing
ω_m, θ_e, i_abc/i_dq, T_e + T_L input; (2) outer speed PI (saturation + anti-windup); (3) inner dq current PI ×2 with decoupling/back-EMF FF (id_ref=0); (4) Clarke/Park transforms on a single global θ_e; (5) load-torque estimator on x=[ω_m;T_L]; (6) feed-forward of T̂_L into iq_ref with an enable. Omitting any one breaks the method.
θ_e Goto TagVisibility='global' is MANDATORY in every plant variant — the base Anti_Park/Plark consume θ_e via an internal From "The"; a default 'local' Goto is the classic silent failure (FOC degenerates to lab-frame open-loop: motor stalls, iabc DC-locked). A build self-test must assert global visibility on every The Goto (look-under-masks). See base/broken_foc_diagnostics.md §F-CRIT 1.- Estimator on the augmented model + observability check — build
x=[ω_m;T_L], u=T_e, y=ω_m with ṪL≈0 (random-walk internal model, F2). Assert observability rank(O)=2 (F3, det≈-1/J≠0) in InitFcn — a rank-deficient model is a build error, not a tuning issue.
- All 7 variants on ONE shared structure = coverage, NOT copy — reproduce the variant structure/tuning method from F4–F10; never copy magic Q/R/pole numbers or a selector topology from any source. Realize the recursive KFs inline (
KF_Estimator_EML atom / inline MATLAB Function) so the model is one-click. The steady-state KF must collapse onto the Luenberger (F7.b) — verify their T̂_L std match as a built-in cross-check.
- Feed-forward enable is mandatory —
iq_ref += (T̂_L/Kt)·ff_enable, with ff_enable toggling FF-on vs FF-off. The headline demonstrable effect is FF-on reduces the load-step speed dip and recovery time; FF-off is the baseline. This is the method's reason to exist (see misconception #3).
- Speed PI = Symmetric Optimum, not pole-zero-cancellation — a PZC/IMC-tuned speed PI has a disturbance-rejection slow pole fixed by the plant mechanical ratio
−B/J, independent of bandwidth (the Phase-4.5 trap: large inertia → long load-settling no matter the gain). Use Symmetric Optimum (a=4, Teq=1/αc) so rejection is bandwidth-dependent, and verify the evaluation window T_window ≥ 5·τ_max (τ_max=2·a·Teq). See base Phase-4.5 sanity check.
- Reproducible measurement noise (fixed seed) — inject
ω_m,meas = ω_m + n with a fixed-seed Random Number at a sub-ts rate. The sensor noise is the KF's reason to exist; without it a plain observer suffices and the Kalman story is unmotivated.
- R2024b estimator sizing recipe + visual 4-check — the
KF_Estimator_EML atom and the inline persistent/continuous charts (KF6/KF7) need their port Size pinned (DataType=Inherit, chart SampleTime='-1'); R2024b output-size inference fails for persistent xhat=zeros(size(A,1),1) and continuous-feedback charts. See building_blocks/foc_ltid_api_notes.md §E.1. Run the base visual 4-check before trusting any metric.
Build Flow
Layered on the base flow (motor-pmsm-base Build Flow); method-specific steps:
| Phase |
Action |
Where |
| 0 |
Validate inputs + base sanity grid (Vdc/BEMF, Goto visibility, FF dimensions, sector-7) |
base/pre_build_grid.md |
| 1 |
Plant: Variant Subsystem (plant_sel) — EQN dq integrator chain ‖ Simscape switched (base atoms by pointer); θ_e Goto global in each variant |
base/plant_modeling.md |
| 2 |
Speed-sensor noise (ω_m,meas = ω_m + n, fixed seed) |
(this skill) Rule 9 |
| 3 |
Outer speed PI (Symmetric Optimum + back-calculation anti-windup + iq saturation) |
../../shared/formulas/pmsm_formulas.md §A |
| 4 |
Inner dq current PI ×2 (IMC) + cross-decoupling/back-EMF FF; id_ref=0 |
formulas/pmsm_foc_ltid_formulas.md F1 |
| 5 |
Estimator bank: augmented F2 model, observability (F3), 7 variants on one selector (F4–F10) |
formulas/pmsm_foc_ltid_formulas.md F2–F10 |
| 6 |
Feed-forward: T̂_L → 1/Kt → ×ff_enable → summed into iq_ref (F8) |
formulas/pmsm_foc_ltid_formulas.md F8 |
| 7 |
Modulation (Simscape variant only): Anti_Park + SVPWM + Universal Bridge |
base/building_blocks.md |
| 8 |
Logger (speed / TLhat ×7 / cur / trq / iabc) + θ_e Goto self-test |
base/measurement_logger.md |
| 9 |
Solver (ode23tb var-step, MaxStep=ts/2) + InitFcn injection + idempotent self-tests |
(this skill) Rule 2 |
| 10 |
Visual 4-check + FF-on/off dip-reduction demo |
base/sanity_visual.md |
The conventional build script is scripts/build_template.m (parameterized; edit the InitFcn parameter block for your machine).
Required User Inputs
Ask before starting. The build template carries generic SPMSM defaults; override for the target machine.
| Group |
Parameters |
| Machine (7) |
Rs, Ld, Lq (mild-saliency Lq/Ld < 2 v1), psif, pn, J, B (viscous; Kt=1.5·pn·psif derived) |
| Current PI (2) |
alpha_c (IMC bandwidth, default 2000 rad/s), Vmax (dq voltage saturation) |
| Speed PI (2) |
a_so (Symmetric-Optimum factor, default 4), iq_max (saturation + Lyapunov-free bound) |
| Estimator (≈6) |
observer poles (variant 1), Qd/Rd (variant 4; Rd=noise_var honest), colored pole a_col + Q3/R3 (3/5), cross-term Mcorr (6), Qc/Rc bridge (7) — all generic, documented as illustrative |
| Noise (3) |
noise_var, noise_seed, ts_noise (default ts/2) |
| Sampling (1) |
ts (controllers/estimators discrete period, default 1e-4) |
| Plant select (1) |
plant_sel (1 = equation-linear baseline, 2 = Simscape switched) |
| Run select (2) |
est_sel (1..7), ff_enable (0/1) |
| Scenario (4) |
wref_val, t_ramp, tL_on/tL_off/TL_val, StopTime |
Simscape (3, only plant_sel=2) |
Vdc_val, Tpwm, Ts (powergui discrete step) |
Estimator variants (formula → realization)
All on x=[ω_m;T_L] (colored variants augment to n=3); all feed the same F8 FF path. 1:1 = coverage, not copy.
| # |
Variant |
Formula |
Realization |
| 1 |
Pole-placed Luenberger |
F4/F5 |
Discrete State-Space, prediction form (Ad−Lp·Cd), Lp=place(Ad',Cd',z)' |
| 2 |
Steady-state KF |
F7 (DARE) |
same DSS realization as #1, gain Lp=Ad·M, M=dlqe(Ad,I,Cd,Qd,Rd) → demonstrates F7.b |
| 3 |
Steady colored KF |
F7 + F9.b case B |
n=3 augmented (Gauss-Markov meas-noise state), dlqe constant gain |
| 4 |
Recursive KF |
F6 |
KF_Estimator_EML atom, n=2, per-step Riccati |
| 5 |
Recursive colored KF |
F6 + F9.b case B |
2nd KF_Estimator_EML instance sized n=3 |
| 6 |
Correlated-noise KF |
F9.a |
inline MATLAB Function, gain carries cross-term M |
| 7 |
Continuous Kalman-Bucy |
F10 |
inline MATLAB Function (continuous Riccati ODE) + continuous Integrator |
F9.b colored variants use case B (shape the measurement noise, keep T_L as state 2): the shared atom hardcodes est_load=xhat(2), so the shaping state must be appended (case A would relocate T_L). Both placements are valid F9.b.
Triggers / Skip
| ✅ Use |
❌ Skip |
| Build / port / extend an FOC speed loop with load-torque estimation + feed-forward |
FCS-MPC, DTC, SMC, sensorless/position estimation, scalar V/Hz, BLDC trapezoidal |
| Luenberger / Kalman-family load-torque observer + FF disturbance rejection |
Induction-motor FOC, SynRM (ψ_f≈0), strong-saliency IPMSM MTPA, weak-field |
| Demonstrating FF-on vs FF-off speed-dip reduction at a load step |
Pure theory (observability proofs, KF derivation), paper writing |
| Generalizing the method to a new PMSM machine parameter set |
MATLAB perf tuning, unit tests |
Generalization Across Sub-Types
| Sub-type |
Constraint |
Strategy |
| SPMSM |
Ld ≈ Lq |
id_ref = 0 |
| IPMSM mild |
Lq > Ld, Lq/Ld < 2 |
id_ref = 0 workable |
| IPMSM strong |
Lq/Ld ≥ 2 |
MTPA mid-loop required (out of v1 scope) |
Topology is invariant: same six modules, same estimator structure, same FF path, same CRIT conditions. The plant can be swapped between the equation-linear baseline (clean mechanical dynamics for the estimator study) and the Simscape switched plant (realism; survives PWM ripple) via plant_sel with no controller change — the estimator/FF layer is plant-agnostic.
Shareable assets (by pointer — do not duplicate)
../../shared/formulas/pmsm_formulas.md — base PMSM physics §0–§7 + speed-PI §A (signed).formulas/pmsm_foc_ltid_formulas.md — method formulas F1 (dq current-PI IMC + decoupling), F2 (augmented state model), F3 (observability), F4/F5 (Luenberger), F6 (recursive KF), F7 (steady-state KF ↔ Luenberger equivalence), F8 (feed-forward law), F9.a/F9.b/F10 (correlated / colored / continuous).../../shared/building_blocks/pmsm_blocks.slx (+ manifest) — base atoms (Clarke/Park/Anti_Park transforms, Simscape PMSM/Universal_Bridge/SVPWM/sources/powergui).building_blocks/foc_ltid_blocks.slx (+ manifest) — the KF_Estimator_EML atom (generic discrete KF recursion; matrices via input ports, zero numerics).building_blocks/foc_ltid_api_notes.md — R2024b platform facts (§A.1 Fcn-no-mod/rem; §E.1 KF sizing recipe).
Sibling Skills
1---2name: motor-foc-ltid-pmsm3description: PMSM FOC + Load-Torque Estimator + Feed-Forward Builder. Build a field-oriented speed controller for a three-phase voltage-source-inverter-driven PMSM (SPMSM / mild-saliency IPMSM via parameterization) in Simulink, augmented with a linear load-torque state estimator (Luenberger + Kalman-filter family, 7 selectable variants on one shared structure) whose estimate is fed forward into the q-axis current reference to reject load-step speed dips. dq current PI ×2 with back-EMF decoupling, Symmetric-Optimum speed PI with anti-windup, selectable equation-linear plant or Simscape switched plant. Use when constructing, reproducing, porting, or extending an FOC speed loop with disturbance/load-torque estimation and feed-forward compensation (keywords FOC, field-oriented control, load-torque observer, load torque estimator, Luenberger observer, Kalman filter load estimation, feed-forward disturbance compensation, LTID, 负载转矩观测器, 前馈补偿, 卡尔曼). Skip for FCS-MPC, DTC, SMC, sensorless/position estimation, scalar V/Hz, BLDC tra4---56# motor-foc-ltid-pmsm — PMSM FOC + Load-Torque Estimator + Feed-Forward Builder78Three-phase 2-level voltage-source inverter + PMSM. **Field-oriented speed control** (outer Symmetric-Optimum speed PI → `iq_ref`; inner dq current PI ×2 with cross-coupling + back-EMF decoupling feed-forward; `id_ref = 0`), augmented with a **linear load-torque state estimator** on the model `x = [ω_m; T_L]`, `u = T_e`, `y = ω_m` — **seven selectable realizations** on one shared structure (pole-placed Luenberger, steady-state KF, steady colored KF, recursive KF, recursive colored KF, correlated-noise KF, continuous Kalman-Bucy). The estimate `T̂_L` is **fed forward** into `iq_ref` (via the torque constant) to cut the load-step speed dip the speed PI alone cannot. v1 baseline supports SPMSM and mild-saliency IPMSM (`Lq/Ld < 2`, `id_ref = 0`); strong-saliency MTPA deferred.910Layered on [motor-pmsm-base](../../.claude/skills/motor-pmsm-base/SKILL.md). All base discipline applies (plant build standard, dq conventions, building-blocks SOP, broken-FOC defense, visual 4-check).1112## ⚠️ Estimator validation note1314The base FOC plant + dq current PI + speed PI formulas are reused by pointer from the base `pmsm_formulas.md` §0–§7, §A. The **load-torque estimator family** (F2–F10: augmented model, observability, Luenberger, recursive/steady/colored/correlated KF, Kalman-Bucy) is documented in `formulas/pmsm_foc_ltid_formulas.md`, each formula cross-checked against ≥2 independent academic sources (see base/[theory_anchor.md](../../.claude/skills/motor-pmsm-base/references/theory_anchor.md)).1516**Validation requirement**: a visual review on the MATLAB desktop (motor rotates / `iq` tracks / `iabc` AC sinusoidal / `Te` energy balance) **plus** the FF-on-vs-FF-off dip-reduction demonstration. Neither can be skipped.1718## Must-Follow Rules19201. **Plan first** — numbered plan with the input table (below), the design-decision choices (discretization path, KF tuning, plant choice — see the build template's parameter block), and the build-script structure. Get user approval before the first `add_block`.212. **One-click reproducibility** — every numeric originates in the model `InitFcn` (machine, PI gains, **all** estimator matrices via `c2d`/`place`/`dlqe`, the augmented `n=3` colored model, the F9.a cross-term, the F10 continuous intensities, plus guarded `ff_enable`/`est_sel`/`plant_sel` defaults). No external design script may need to run first. See base one-click discipline.223. **The six structural modules are non-negotiable** — (1) plant exposing `ω_m, θ_e, i_abc/i_dq, T_e` + `T_L` input; (2) outer speed PI (saturation + anti-windup); (3) inner dq current PI ×2 with decoupling/back-EMF FF (`id_ref=0`); (4) Clarke/Park transforms on a single global `θ_e`; (5) load-torque estimator on `x=[ω_m;T_L]`; (6) feed-forward of `T̂_L` into `iq_ref` with an enable. Omitting any one breaks the method.234. **`θ_e` Goto `TagVisibility='global'` is MANDATORY in every plant variant** — the base `Anti_Park`/`Plark` consume `θ_e` via an internal `From "The"`; a default `'local'` Goto is the classic silent failure (FOC degenerates to lab-frame open-loop: motor stalls, `iabc` DC-locked). A build self-test must assert global visibility on every `The` Goto (look-under-masks). See base/[broken_foc_diagnostics.md](../../.claude/skills/motor-pmsm-base/references/broken_foc_diagnostics.md) §F-CRIT 1.245. **Estimator on the augmented model + observability check** — build `x=[ω_m;T_L]`, `u=T_e`, `y=ω_m` with `ṪL≈0` (random-walk internal model, F2). Assert observability `rank(O)=2` (F3, `det≈-1/J≠0`) in `InitFcn` — a rank-deficient model is a build error, not a tuning issue.256. **All 7 variants on ONE shared structure = coverage, NOT copy** — reproduce the variant *structure/tuning method* from F4–F10; never copy magic Q/R/pole numbers or a selector topology from any source. Realize the recursive KFs **inline** (`KF_Estimator_EML` atom / inline MATLAB Function) so the model is one-click. The steady-state KF must collapse onto the Luenberger (F7.b) — verify their `T̂_L` std match as a built-in cross-check.267. **Feed-forward enable is mandatory** — `iq_ref += (T̂_L/Kt)·ff_enable`, with `ff_enable` toggling FF-on vs FF-off. The headline demonstrable effect is **FF-on reduces the load-step speed dip and recovery time**; FF-off is the baseline. This is the method's reason to exist (see misconception #3).278. **Speed PI = Symmetric Optimum, not pole-zero-cancellation** — a PZC/IMC-tuned speed PI has a disturbance-rejection slow pole fixed by the plant mechanical ratio `−B/J`, **independent of bandwidth** (the Phase-4.5 trap: large inertia → long load-settling no matter the gain). Use Symmetric Optimum (`a=4`, `Teq=1/αc`) so rejection is bandwidth-dependent, and verify the evaluation window `T_window ≥ 5·τ_max` (`τ_max=2·a·Teq`). See base Phase-4.5 sanity check.289. **Reproducible measurement noise (fixed seed)** — inject `ω_m,meas = ω_m + n` with a fixed-seed `Random Number` at a sub-`ts` rate. The sensor noise is the KF's reason to exist; without it a plain observer suffices and the Kalman story is unmotivated.2910. **R2024b estimator sizing recipe + visual 4-check** — the `KF_Estimator_EML` atom and the inline persistent/continuous charts (KF6/KF7) need their port `Size` **pinned** (DataType=Inherit, chart `SampleTime='-1'`); R2024b output-size inference fails for `persistent xhat=zeros(size(A,1),1)` and continuous-feedback charts. See `building_blocks/foc_ltid_api_notes.md` §E.1. Run the base visual 4-check before trusting any metric.3031## Build Flow3233Layered on the base flow ([motor-pmsm-base](../../.claude/skills/motor-pmsm-base/SKILL.md) Build Flow); method-specific steps:3435| Phase | Action | Where |36|---|---|---|37| 0 | Validate inputs + base sanity grid (Vdc/BEMF, Goto visibility, FF dimensions, sector-7) | base/[pre_build_grid.md](../../.claude/skills/motor-pmsm-base/references/pre_build_grid.md) |38| 1 | Plant: **Variant Subsystem** (`plant_sel`) — EQN dq integrator chain ‖ Simscape switched (base atoms by pointer); `θ_e` Goto global in **each** variant | base/[plant_modeling.md](../../.claude/skills/motor-pmsm-base/references/plant_modeling.md) |39| 2 | Speed-sensor noise (`ω_m,meas = ω_m + n`, fixed seed) | (this skill) Rule 9 |40| 3 | Outer speed PI (Symmetric Optimum + back-calculation anti-windup + `iq` saturation) | `../../shared/formulas/pmsm_formulas.md` §A |41| 4 | Inner dq current PI ×2 (IMC) + cross-decoupling/back-EMF FF; `id_ref=0` | `formulas/pmsm_foc_ltid_formulas.md` F1 |42| 5 | Estimator bank: augmented F2 model, observability (F3), **7 variants** on one selector (F4–F10) | `formulas/pmsm_foc_ltid_formulas.md` F2–F10 |43| 6 | Feed-forward: `T̂_L` → `1/Kt` → `×ff_enable` → summed into `iq_ref` (F8) | `formulas/pmsm_foc_ltid_formulas.md` F8 |44| 7 | Modulation (Simscape variant only): Anti_Park + SVPWM + Universal Bridge | base/[building_blocks.md](../../.claude/skills/motor-pmsm-base/references/building_blocks.md) |45| 8 | Logger (speed / TLhat ×7 / cur / trq / iabc) + `θ_e` Goto self-test | base/[measurement_logger.md](../../.claude/skills/motor-pmsm-base/references/measurement_logger.md) |46| 9 | Solver (`ode23tb` var-step, `MaxStep=ts/2`) + InitFcn injection + idempotent self-tests | (this skill) Rule 2 |47| 10 | Visual 4-check + FF-on/off dip-reduction demo | base/[sanity_visual.md](../../.claude/skills/motor-pmsm-base/references/sanity_visual.md) |4849The conventional build script is `scripts/build_template.m` (parameterized; edit the `InitFcn` parameter block for your machine).5051## Required User Inputs5253Ask before starting. The build template carries generic SPMSM defaults; override for the target machine.5455| Group | Parameters |56|---|---|57| **Machine** (7) | `Rs`, `Ld`, `Lq` (mild-saliency `Lq/Ld < 2` v1), `psif`, `pn`, `J`, `B` (viscous; `Kt=1.5·pn·psif` derived) |58| **Current PI** (2) | `alpha_c` (IMC bandwidth, default 2000 rad/s), `Vmax` (dq voltage saturation) |59| **Speed PI** (2) | `a_so` (Symmetric-Optimum factor, default 4), `iq_max` (saturation + Lyapunov-free bound) |60| **Estimator** (≈6) | observer poles (variant 1), `Qd`/`Rd` (variant 4; `Rd=noise_var` honest), colored pole `a_col` + `Q3`/`R3` (3/5), cross-term `Mcorr` (6), `Qc`/`Rc` bridge (7) — all generic, documented as illustrative |61| **Noise** (3) | `noise_var`, `noise_seed`, `ts_noise` (default `ts/2`) |62| **Sampling** (1) | `ts` (controllers/estimators discrete period, default 1e-4) |63| **Plant select** (1) | `plant_sel` (1 = equation-linear baseline, 2 = Simscape switched) |64| **Run select** (2) | `est_sel` (1..7), `ff_enable` (0/1) |65| **Scenario** (4) | `wref_val`, `t_ramp`, `tL_on`/`tL_off`/`TL_val`, `StopTime` |66| **Simscape** (3, only `plant_sel=2`) | `Vdc_val`, `Tpwm`, `Ts` (powergui discrete step) |6768## Estimator variants (formula → realization)6970All on `x=[ω_m;T_L]` (colored variants augment to `n=3`); all feed the same F8 FF path. **1:1 = coverage, not copy.**7172| # | Variant | Formula | Realization |73|---|---|---|---|74| 1 | Pole-placed Luenberger | F4/F5 | `Discrete State-Space`, prediction form `(Ad−Lp·Cd)`, `Lp=place(Ad',Cd',z)'` |75| 2 | Steady-state KF | F7 (DARE) | **same DSS realization** as #1, gain `Lp=Ad·M`, `M=dlqe(Ad,I,Cd,Qd,Rd)` → demonstrates F7.b |76| 3 | Steady colored KF | F7 + F9.b case B | `n=3` augmented (Gauss-Markov meas-noise state), `dlqe` constant gain |77| 4 | Recursive KF | F6 | `KF_Estimator_EML` atom, `n=2`, per-step Riccati |78| 5 | Recursive colored KF | F6 + F9.b case B | 2nd `KF_Estimator_EML` instance sized `n=3` |79| 6 | Correlated-noise KF | F9.a | inline MATLAB Function, gain carries cross-term `M` |80| 7 | Continuous Kalman-Bucy | F10 | inline MATLAB Function (continuous Riccati ODE) + continuous `Integrator` |8182> **F9.b colored variants use case B** (shape the *measurement* noise, keep `T_L` as state 2): the shared atom hardcodes `est_load=xhat(2)`, so the shaping state must be appended (case A would relocate `T_L`). Both placements are valid F9.b.8384## Triggers / Skip8586| ✅ Use | ❌ Skip |87|---|---|88| Build / port / extend an FOC speed loop with load-torque estimation + feed-forward | FCS-MPC, DTC, SMC, sensorless/position estimation, scalar V/Hz, BLDC trapezoidal |89| Luenberger / Kalman-family load-torque observer + FF disturbance rejection | Induction-motor FOC, SynRM (`ψ_f≈0`), strong-saliency IPMSM MTPA, weak-field |90| Demonstrating FF-on vs FF-off speed-dip reduction at a load step | Pure theory (observability proofs, KF derivation), paper writing |91| Generalizing the method to a new PMSM machine parameter set | MATLAB perf tuning, unit tests |9293## Generalization Across Sub-Types9495| Sub-type | Constraint | Strategy |96|---|---|---|97| SPMSM | `Ld ≈ Lq` | `id_ref = 0` |98| IPMSM mild | `Lq > Ld`, `Lq/Ld < 2` | `id_ref = 0` workable |99| IPMSM strong | `Lq/Ld ≥ 2` | MTPA mid-loop required (out of v1 scope) |100101Topology is invariant: same six modules, same estimator structure, same FF path, same CRIT conditions. The **plant** can be swapped between the equation-linear baseline (clean mechanical dynamics for the estimator study) and the Simscape switched plant (realism; survives PWM ripple) via `plant_sel` with no controller change — the estimator/FF layer is plant-agnostic.102103## Shareable assets (by pointer — do not duplicate)104105- `../../shared/formulas/pmsm_formulas.md` — base PMSM physics §0–§7 + speed-PI §A (signed).106- `formulas/pmsm_foc_ltid_formulas.md` — method formulas **F1** (dq current-PI IMC + decoupling), **F2** (augmented state model), **F3** (observability), **F4/F5** (Luenberger), **F6** (recursive KF), **F7** (steady-state KF ↔ Luenberger equivalence), **F8** (feed-forward law), **F9.a/F9.b/F10** (correlated / colored / continuous).107- `../../shared/building_blocks/pmsm_blocks.slx` (+ manifest) — base atoms (Clarke/Park/Anti_Park transforms, Simscape PMSM/Universal_Bridge/SVPWM/sources/powergui).108- `building_blocks/foc_ltid_blocks.slx` (+ manifest) — the `KF_Estimator_EML` atom (generic discrete KF recursion; matrices via input ports, zero numerics).109- `building_blocks/foc_ltid_api_notes.md` — R2024b platform facts (§A.1 Fcn-no-mod/rem; §E.1 KF sizing recipe).110111## Sibling Skills112113- [motor-pmsm-base](../../.claude/skills/motor-pmsm-base/SKILL.md) — base infrastructure114- [motor-fcs-mpc](../../.claude/skills/motor-fcs-mpc/SKILL.md) — FCS-MPC current control115- [motor-dtc-pmsm](../../.claude/skills/motor-dtc-pmsm/SKILL.md) — Direct Torque Control116- [motor-smc-pmsm](../../.claude/skills/motor-smc-pmsm/SKILL.md) — Sliding Mode Control speed loop
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