Public EV charging infrastructure suffers from significant failure rates -- with field studies reporting up to 27.5% of DC fast chargers non-functional -- and multi-day mean time to resolution, imposing billions in annual economic burden. Cloud-centric architectures cannot achieve the latency, reliability, and bandwidth characteristics required for autonomous operation. We present Auralink SDC (Software-Defined Charging), an architecture deploying domain-specialized AI agents at the network edge for autonomous charging infrastructure management. Key contributions include: (1) Confidence-Calibrated Autonomous Resolution (CCAR), enabling autonomous remediation with formal false-positive bounds; (2) Adaptive Retrieval-Augmented Reasoning (ARA), combining dense and sparse retrieval with dynamic context allocation; (3) Auralink Edge Runtime, achieving sub-50ms TTFT on commodity hardware under PREEMPT_RT constraints; and (4) Hierarchical Multi-Agent Orchestration (HMAO). Implementation uses AuralinkLM models fine-tuned via QLoRA on a domain corpus spanning OCPP 1.6/2.0.1, ISO 15118, and operational incident histories. Evaluation on 18,000 labeled incidents in a controlled environment establishes 78% autonomous incident resolution, 87.6% diagnostic accuracy, and 28-48ms TTFT latency (P50). This work presents architecture and implementation patterns for edge-deployed industrial AI systems with safety-critical constraints.
Figures & tables
Task
General
Adapted
Δ
General knowledge
89.2%
87.8%
-1.4
OCPP protocol
44.7%
92.1%
+47.4
Fault diagnosis
38.1%
87.6%
+49.5
Remediation
41.8%
84.3%
+42.5
Safety assessment
52.3%
93.2%
+40.9
ISO 15118
35.2%
89.7%
+54.5
Table 1: Baseline LLM Performance on EV Charging Tasks. “General” is Mistral Large 3 base (zero-shot, no domain context); “Adapted” is AuralinkLM 14B after QLoRA fine-tuning. Each category evaluated on 200–500 held-out examples using exact-match accuracy. Expert judgment applied to open-ended diagnostic responses.
Approach
Edge
LLM
Auto
Off.
Open
Rule CSMS
✗
✗
✗
Part.
Prop.
Cloud AI
✗
✓
Part.
✗
Prop.
Edge GW
✓
✗
✗
✓
Mix
Acad. RAG
Part.
✓
Part.
✗
✓
Ours
✓
✓
✓
✓
✓
Table 2: Comparison with Existing Approaches
Figure 1: Three-tier Auralink SDC architecture
Figure 2: Detailed Auralink SDC system architecture showing component interactions across all three tiers. The edge tier contains the core AI capabilities (DiagnosticEngine, ARA, CCAR) enabling autonomous operation. Latency figures represent P50 inference times on target hardware.
Table 6: Model Deployment Configuration. P50 and P99 denote the 50th and 99th percentile latency (TTFT), respectively.
Category
Count
Source
OCPP 1.6
8,432
Spec + synthetic Q&A
OCPP 2.0.1
9,847
Spec + synthetic Q&A
Fault Diagnosis
41,234
Historical incidents
Remediation
34,567
Service manuals
Power Electronics
24,891
Engineering docs
Session Management
18,432
Operational logs
Table 7: Training Corpus Composition
Parameter
Value
Rank ( r )
64
Alpha ( α )
32
Dropout
0.05
Target Modules
q,k,v,o,gate,up,down
Learning Rate
2×10−4 (cosine)
Warmup Steps
100
Table 8: QLoRA Hyperparameters
Figure 3: QLoRA fine-tuning pipeline: curated domain-specific training corpus processed through three-stage curriculum learning, producing domain-adapted model subsequently quantized to Q4_K_M (8.2 GB) for edge deployment.
Precision
Size
Acc.
P50
FP16
28.0 GB
89.4%
142ms
INT8 (Q8_0)
14.0 GB
89.1%
68ms
Q5_K_M
9.8 GB
88.4%
42ms
Q4_K_M
8.2 GB
87.6%
28ms
Q4_K_S
7.6 GB
86.9%
26ms
IQ4_XS
7.2 GB
85.8%
24ms
Table 9: Quantization Impact: AuralinkLM 14B
Platform
CPU
NPU
Speedup
AMD XDNA 2
48ms
28ms
1.71 ×
Intel AI Boost
62ms
42ms
1.48 ×
Qualcomm Hexagon
85ms
52ms
1.63 ×
Table 10: NPU Offloading Performance
Metric
P99
Max
Interrupt latency
38\SIUnitSymbolMicros
52\SIUnitSymbolMicros
Scheduling latency
72\SIUnitSymbolMicros
98\SIUnitSymbolMicros
Timer jitter
8\SIUnitSymbolMicros
15\SIUnitSymbolMicros
Context switch
6\SIUnitSymbolMicros
11\SIUnitSymbolMicros
Inference start
124\SIUnitSymbolMicros
187\SIUnitSymbolMicros
Table 11: Real-Time Timing Metrics
Figure 4: CCAR decision flow (simplified representation). Actions above τauto=0.90 execute autonomously without notification; actions between 0.85 and 0.90 execute with operator notification; between τassist=0.70 and 0.85 require human confirmation; below τassist escalate to manual resolution. See Table 12 for the full five-tier decision matrix.
Confidence
Action
C≥0.90
Execute autonomously, log only
0.85≤C<0.90
Execute with operator notification
0.70≤C<0.85
Recommend, await approval (timeout: 4h)
0.50≤C<0.70
Escalate with full context
C<0.50
Human expert required
Table 12: CCAR Decision Thresholds
Document Type
Docs
Chunks
OCPP Specifications
18
18,432
OEM Service Manuals
347
58,234
Technical Bulletins
1,234
42,847
ISO/IEC Standards
52
14,123
Historical Resolutions
2,847
72,345
Grid Codes
28
8,432
Table 13: ARA Knowledge Base Composition
Metric
Value
Recall@5
95.2%
Precision@5
91.4%
MRR (Mean Reciprocal Rank)
0.924
NDCG@10
0.912
Retrieval Latency (P50)
18ms
Retrieval Latency (P99)
42ms
Table 14: ARA Retrieval Metrics
Figure 5: HMAO agent hierarchy with intent routing. Dashed lines indicate inter-agent collaboration for complex multi-domain incidents. Model sizes (0.5B/14B) indicate AuralinkLM deployment tier.
Agent
Responsibility
Model
AutoOps
Fault diagnosis
14B
TechSupport
Guided repair
14B
OpsMgmt
Fleet analytics
14B
DriverAssist
Session support
0.5B
CodeGen
API integration
14B
Table 15: Specialized Agent Configuration
Component
Specification
Cloud Infrastructure
GPU Cluster
NVIDIA H100/H200 (distributed)
Model
AuralinkLM 675B (675B MoE, 4+1 active experts)
Context
128K tokens (of 256K max)
Edge Deployment (Primary)
CPU
AMD Ryzen AI Max+ 395 (Strix Halo)
Table 16: Evaluation Hardware Specifications
Incident Type
Fraction
Communication
30.0%
Authorization
18.0%
Power Elec.
15.0%
Firmware/SW
13.0%
Mechanical
10.0%
Payment Processing
8.0%
Table 17: Test Incident Distribution (Controlled Testing Corpus)
System
Auto
Acc.
P50
MTTR
Off.
Rule-Based
0%
44.7%
5ms
96h
Yes
Cloud (A)
28.4%
72.3%
420ms
28h
No
Cloud (B)
31.2%
74.8%
380ms
24h
No
Non-FT
22.1%
52.3%
32ms
42h
Yes
Ours
78% †
87.6% †
28ms
4–8h †
Yes
Table 18: Comprehensive Baseline Comparison
Parameter
Value (simulation)
Simulated stations
1,000-charger reference
Operator profiles
23 (modeled)
Country profiles
14 (EU + UK + CH + NO)
Testing period
Controlled testing
Simulated sessions
Representative sample
Diagnostic scenarios
Representative corpus
Table 19: Simulation and Testing Parameters
System
Auto%
MTTR
FP%
FN%
Traditional
0%
96h
42%
–
Cloud-AI a
31.2%
24h
11%
8%
Human Expert
–
68h
6%
4%
Auralink SDC
78% †
4–8h †
3.8%
5.2%
Table 20: Autonomous Resolution: System Comparison
Category
Acc.
Prec.
Rec.
F1
Comms
91.8%
90.2%
93.4%
0.918
Auth
90.4%
92.1%
88.7%
0.904
Power Elec.
85.2%
82.8%
87.9%
0.853
Firmware
89.3%
91.2%
87.4%
0.893
Mechanical
79.8%
77.2%
82.6%
0.798
Payment
88.7%
89.4%
87.9%
0.886
Table 21: Diagnostic Accuracy by Fault Category
Failure Mode
% of Failures
Low confidence (escalated)
50.0%
Hardware replacement req.
28.0%
Multi-fault complexity
11.0%
Novel fault pattern
6.0%
False negative (missed)
5.0%
Total failures
100%
Table 22: Failure Mode Distribution (Controlled Testing)
Configuration
Acc.
Auto%
Δ Acc
Full system
87.6% †
78% †
—
− Domain fine-tuning
52.3%
22.1%
− 35.3
− ARA retrieval
79.2%
61.4%
− 8.4
− CCAR calibration
87.1%
42.8%
− 0.5
− Curriculum learning
84.3%
72.1%
− 3.3
− Multi-agent routing
85.8%
74.2%
− 1.8
Table 23: Ablation Study: Component Contributions
Configuration
P50
P95
P99
Cloud (675B)
285ms †
520ms
890ms
Edge GPU (14B)
28ms
52ms
78ms
Agent FW (0.5B)
11ms
24ms
34ms
Full pipeline
67ms
124ms
187ms
Table 24: Inference Latency (TTFT for model components; end-to-end for full pipeline)
Horizon
Prec.
Rec.
F1
FPR
24h
94.0% †
84.2%
0.888
1.2%
48h
94.7%
79.8%
0.866
2.1%
72h
92.4%
75.1%
0.829
3.4%
7d
85.2%
68.7%
0.761
5.8%
Table 25: Predictive Maintenance by Horizon
Category
Trad.
Auralink
SW licensing
$129K
$0
Service
$165K
$126K
Field service
$900K
$375K
Downtime
$219K
$72K
Infrastructure
—
$90K
Total
$1,413K
$663K
Table 26: Three-Year TCO Analysis
Appendix figures & tables1 asset
Supplementary material from the paper’s appendix.
Appendix
Platform
0.5B
14B
TDP
AMD Strix Halo
142
38
45–120W
NVIDIA DGX Spark
385
95
140W
NVIDIA RTX 5090
512 ‡
128 ‡
575W
NVIDIA Jetson Thor
52
12
40–130W
Apple M4 Max
128
34
∼ 50W
Qualcomm X Elite
87
21
23W
Appendix
Table 27: AuralinkLM Inference by Platform (tokens/sec)
School of Management, Foshan University, Foshan, China · School of Management, Foshan University, Foshan 528000, China · School of Mathematics, Foshan University, Foshan 528000, China +5