The electric vehicle charging pile test system is core equipment for R&D, production line inspection, grid access certification, operation and maintenance of charging piles, undertaking full-process tests including electrical performance, protocol conformance, safety function, environmental adaptability and durability cycling. The high‑voltage programmable power supply acts as the key power unit of the test system, simulating normal and abnormal grid conditions and providing standardized AC input for charging piles. Its grid simulation capability, output programmability, dynamic response speed, harmonic superposition performance and long-term stability directly determine the accuracy, compliance and reliability of test results. Current mainstream requirements specify AC output of 0~450 V single‑phase / 0~690 V three‑phase, adjustable frequency 45~65 Hz, voltage accuracy ≤±0.2% FS, frequency accuracy ≤±0.01 Hz, dynamic response ≤5 ms, supporting simulation of voltage sag/swell/interruption, harmonic injection, three‑phase unbalance and flicker, together with high power factor, low THD and bidirectional energy flow. Traditional regulated power supplies suffer from weak grid simulation, slow dynamics, lack of programmable harmonic output and insufficient coverage for full-condition tests, failing official certification requirements. The design strictly complies with GB/T 18487, GB/T 20234, GB/T 17626, IEC 61000‑4 and related standards, supporting automatic testing, multi-condition programmability and safety interlock. This methodology establishes a full-process framework covering grid-simulation topology, full-condition programmable control, fast dynamic optimization, harmonic superposition algorithms, charging-pile scenario adaptation and safety protection, applicable to AC/DC charging piles, charging modules and battery swap station equipment, providing standardized guidelines for domestic test equipment upgrading. Targeting grid simulation, wide-range programmability, fast dynamics and bidirectional flow, the solution adopts a two-stage topology: front-end bidirectional PFC rectifier + rear-end three-level NPC inverter + fully digital programmable control with grid modeling and feedforward compensation, overcoming traditional limitations and achieving high-precision full-condition grid simulation with fast response. Five core principles are defined. First, a back-to-back bidirectional converter realizes energy circulation and comprehensive grid emulation. The front three-phase Vienna PFC achieves unity power factor (≥0.99), low THD (≤3%), rectifying grid AC to stable DC bus or regenerating energy back to the grid with high efficiency, while providing electrical isolation. The rear three-level NPC inverter delivers smoother output with lower dv/dt, less EMI and reduced device stress. With SPWM modulation, amplitude/frequency/phase are fully programmable, enabling accurate harmonic injection and four‑quadrant operation to supply or absorb reactive/active power from charging piles. Second, a dual DSP+FPGA digital control architecture executes core algorithms and grid modeling on DSP, while FPGA implements high-speed PWM, sampling, harmonic superposition and hardware protection with loop update ≥20 kHz and harmonic modulation ≥100 kHz. An integrated standard grid condition library fully covers GB/T 17626 and IEC 61000‑4 immunity tests including sag/swell/interruption, gradual voltage change, unbalance, frequency deviation, harmonics/interharmonics, flicker, spikes and EFT; users can apply standard templates or customize amplitude, duration, phase and harmonic parameters freely. Third, fast dynamic response adopts dual closed-loop composite control with feedforward. The outer voltage loop uses proportional-resonant (PR) control for zero steady-state tracking of AC waveforms with bandwidth ≥10 kHz; the inner current loop uses deadbeat predictive control for response ≤1 ms. Load and DC bus feedforward pre-adjust PWM within one cycle during transient changes, limiting voltage deviation ≤±2% and recovery ≤5 ms during load steps, meeting dynamic test requirements. Fourth, high-precision harmonic generation based on FFT enables independent programming of 2nd~50th harmonics with accurate amplitude/phase setting and error ≤±5%, supporting interharmonics per IEC 61000‑4‑7. Optimized SVPWM plus random carrier reduces low-order harmonics, achieving output THD ≤1%. Closed-loop harmonic correction compensates load-induced attenuation to maintain stable injection accuracy. Fifth, charging-pile scenario integration embeds standard test templates for input range, frequency tolerance, sag immunity, harmonic immunity, unbalance adaptability, efficiency, power factor and durability, supporting one-click automatic testing. Microsecond synchronous triggering connects protocol analyzers, power analyzers and environmental chambers for fully automated workflows. Full data logging enables traceability and standardized reports. Bidirectional energy feedback ≥94% reduces power consumption during cycling tests, while adjustable leading/lagging power factor (0~1) supports power factor verification. Parallel expansion scales power for high-power charging stacks with current sharing ≤±1%. Grid simulation and dynamic response optimization form the core. Standard steady-state/transient/power-quality models cover adjustable voltage (0~120% rated), frequency (45~65 Hz), power factor (−1~+1), sag/swell/interruption timing ≤1 ms, unbalance, flicker and harmonics. Visual condition editing supports sequential multi-step testing with saved templates. Enhanced dual closed-loop control with QPR and multi-resonant loops ensures precise harmonic tracking; deadbeat current control improves disturbance rejection by over 80%. Multi-dimensional feedforward guarantees seamless condition switching ≤1 ms. DC bus stabilization maintains fluctuation ≤±5% under bidirectional power flow. Adaptive control copes with non-linear rectifier/PFC loads, preserving waveform quality under severe harmonic injection and 100% unbalance with output unbalance ≤1%. Adjustable current limiting supports short-circuit simulation for protection verification. Master-slave parallel synchronization via fiber achieves ≤1 μs carrier alignment and current sharing ≤±1%, enabling scalable MW-level systems with fault redundancy and multi-channel independent grid emulation for mass production lines. Reliability and compliance adopt full-lifecycle component derating (voltage ≤70%, current ≤60%, temperature ≤80%), high-reliability SiC MOSFET/IGBT, efficient liquid/air cooling with uniform temperature distribution and MTBF ≥40,000 hours for long-duration durability tests. EMC design includes three-stage EMI filters, double-layer shielding, fiber isolation and low dv/dt three-level modulation to meet conducted/radiated immunity standards without interfering with high-precision test instruments. Twelve-layer redundant hardware/software protection covers overvoltage/overcurrent/overtemperature, unbalance, islanding, safety interlock and emergency stop with hardware response ≤1 μs, dual current limiting and mandatory high-voltage discharge for operator safety. Fully compliant with national charging standards, rich industrial communication protocols ensure seamless integration with mainstream automatic test platforms for laboratory and production applications. In summary, this complete technical framework solves traditional weaknesses including poor grid simulation, slow dynamics, low programmability and insufficient harmonic accuracy. Back-to-back bidirectional topology realizes efficient energy regeneration; fully digital control delivers standard-compliant grid emulation; composite feedforward control achieves dynamic response within 5 ms. Widely used for R&D, certification and production testing of AC/DC charging piles, modules and swap stations, it provides core support for domestic substitution and performance improvement of China’s charging test equipment.