Driven by the trends of home appliance inverterization and high energy efficiency, washing machines—as core "white goods"—now face stricter requirements for drive efficiency, acoustic comfort, and reliability.
SHYSEMI, leveraging its self-developed core components and algorithms, introduces a full-power-range inverter washing machine solution. Covering 300W to 1500W, it is compatible with top-load, front-load, and washer-dryer combos. Centered on "Self-developed IPM + 6th Gen IGBT + Sensorless FOC Algorithm," this solution balances performance with cost, assisting manufacturers in the rapid deployment of high-efficiency, highly competitive models.
1. IPM Solution Architecture
The solution adopts the classic topology of "PFC Power Correction + IPM Inverter Drive + BLDC Motor Closed-loop Control." Its core advantages lie in integrated design and algorithmic optimization, which significantly simplify hardware layout and enhance operational stability.
1.1 Breakdown of the Three Core Links
- Power Supply Link: Main Input → SHYSEMI SiC SBD PFC (Power Factor Correction) → High-voltage Bus → Three-phase Inverter Bridge (IPM/IGBT) → BLDC Direct Drive Motor.
- Control Link: 32-bit MCU (Built-in FOC Algorithm) → Drive Signals → IPM Module → Motor Speed/Torque Closed-loop Adjustment.
- Protection Link: Full-link monitoring including NTC temperature sensing, over-current, under-voltage, over-temperature, phase-loss, and rotor-lock, featuring 0.1μs ultra-fast response to prevent device damage.
1.2 Hardware Components
The hardware utilizes a modular design with core components developed in-house by SHYSEMI, ensuring strong compatibility and high consistency without complex peripheral adaptation:
- Main Control Unit: 32-bit ARM-core MCU, supporting hardware MAC/DSP, specifically optimized for Sensorless FOC and SVPWM modulation algorithms with fast response times.
- Power Core: SYIM756C-SFT/SST IPM modules (integrating 3-phase bridge + PFC + driver + protection) providing a one-stop power drive solution.
- Sampling & Feedback: Single/dual resistor current sampling, bus voltage detection, and real-time NTC temperature monitoring with high precision and low cost.
- Power Management: Bootstrap circuits, auxiliary power supply, and low-power standby modules, balancing operational efficiency and standby energy consumption.
2. Detailed View of Core IPM Components
The components are the "heart" of the inverter solution. SHYSEMI has developed specialized power devices for washing machine scenarios, balancing efficiency, reliability, and cost.
2.1 Lead Device: SYIM756C IPM Module
As the core power device, the SYIM756C series is customized for washing machine inverter scenarios, featuring high integration and excellent heat dissipation. It is the preferred choice for mid-range front-load and washer-dryer combos.
Key Parameters & Advantages:
- Packaging: SIP-35 (IMS Insulated Metal Substrate), increasing heat dissipation efficiency by 25% and reducing temperature rise by 15°C+.
- Power Specs: Three-phase bridge 15A/600V (Self-developed Trench FS IGBT), PFC 30A/600V (SiC SBD version).
- Integrated Functions: 7-channel HVIC driver, high/low bridge interlocking, and protection for over-current, under-voltage, and over-temperature—eliminating the need for extra protection components.
- Compatibility: TTL/CMOS level compatible, fits all mainstream MCUs, allowing for direct replacement without hardware modification.
- Efficiency: The SiC SBD version achieves a system efficiency of 94.8%; long-term operational efficiency remains above 90%, offering more significant energy savings than traditional FRD solutions.
2.2 Component Selection Guide by Power Rating
3. Core Technology: Sensorless FOC Vector Control
The secret to "Ultra-quiet & High Efficiency" lies in the optimized Sensorless FOC algorithm, which achieves efficient, smooth motor operation across all speed ranges through precise torque and flux decoupling.
3.1 Algorithm Core Workflow
- Clarke + Park Transformation: Converts three-phase current into torque and flux components in a rotating coordinate system to achieve decoupling.
- Precision PID Regulation: Performs closed-loop adjustment of torque and flux with a dynamic response time of <10ms.
- SVPWM Modulation: Outputs optimized voltage vectors, reducing harmonic content by 30% and minimizing motor vibration and noise.
- Rotor Observer: Estimates rotor position without extra sensors, achieving a speed accuracy of ±0.5%.
- Field Weakening Control: Supports a wide speed range from 50 to 16,000 RPM, ensuring high-speed stability during spinning and low-speed smoothness during washing.
3.2 Performance Breakthroughs
- Low-speed Smoothness: Stable operation at an ultra-low 50 RPM ensures no jitter during washing and minimizes clothing wear.
- Dynamic Torque: Startup torque is increased by 40%, preventing stalls under heavy loads (e.g., large laundry items).
- Acoustic Optimization: Operating noise ≤25dB (approx. 10dB lower than traditional solutions), ideal for quiet home environments.
- Significant Savings: Over 50% more power-efficient than fixed-frequency washers, easily meeting National Grade 1 energy standards.
4. Core Advantages vs. Traditional Solutions
- Ultimate Efficiency: PFC + SiC SBD combination reaches 90%-94.8% efficiency. Standby power <0.5W (meets EU ErP and China's new energy standards).
- High Integration: IPM integrates 7 major functions (PFC + 3-phase bridge + Driver + Protection), reducing peripheral components and PCB area by 30%.
- Quiet & Low EMI: SVPWM reduces EMI by 40%. Vibration suppression algorithms ensure noise ≤25dB.
- Cost Control: Self-developed chain (Chip-Package-Test) reduces BOM costs by 15%-20%. SMT yield >99.5%.
5. Comparison Table (Mid-range Front-load Example)
6. Application Scenarios & Success Cases
- Full Coverage: From 300W top-load models to 1500W premium washer-dryer combos.
- Top Brand Case: A 10kg front-load washer using the SYIM756C-SST (SiC) solution achieved Grade 1 energy efficiency and 24dB noise, with mass production exceeding 1 million units.
- Export Success: Meets UL/CE standards with 0.45W standby power, satisfying European and Southeast Asian energy requirements.
7. Design Key Points & FAE Support
- Thermal Design: Recommends IMS + Aluminum substrate with 2mm thermal pads.
- EMC Optimization: Series 10-33Ω resistors in the drive loop and X2 capacitors on the bus side.
- Algorithm Adaptation: Complete FOC parameter library allows for debugging within 1 day.
- FAE Services: Comprehensive support from hardware reference design and PCB layout to sample testing and mass production guidance.
FAQ
Q: What is Sensorless FOC?
A: It is a control method that calculates rotor position/speed using stator voltage/current sampling and mathematical observers, eliminating the need for Hall sensors or encoders.
Q: Role of FOC in washing machines?
A: It enables high durability, fabric protection, high-speed stability, and low noise—marking the technical barrier between entry-level and high-end washers.
Q: What is PFC?
A: Power Factor Correction improves the power factor by aligning voltage and current phases, enhancing efficiency, reducing harmonics, and resisting grid fluctuations.
