How to Choose EV Motor Systems for Suzuki Carry? (144V 25kW Rated, 45kW Max, PMSM, Liquid-Cooled) – Technical Parameters Guide
Selecting the right permanent magnet synchronous motor (PMSM) system for your Suzuki Carry EV conversion requires meticulous attention to technical parameters to ensure optimal performance, efficiency, and safety. Here’s a breakdown of critical specifications to evaluate:
Voltage & Power Compatibility Verify the motor’s rated voltage is 144V ±5% to align with your battery pack. A 25kW (≈33.5HP) rated power ensures smooth city driving, while a 45kW (≈60HP) peak power (for 30-60 seconds) provides ample acceleration and hill-climbing ability. Confirm the inverter’s DC input range matches the battery’s voltage window (e.g., 120-168V) to avoid overvoltage/undervoltage shutdowns.
Torque & Speed Curve Aim for 100-120Nm of continuous torque at 1,500-2,500 RPM for daily driving and 180-220Nm peak torque (≤3,500 RPM) for quick starts. The base speed should be 1,800-2,200 RPM to keep highway speeds (80km/h) at 60-70% of the motor’s max speed. A 5,000-6,000 RPM redline ensures the top speed meets your target (e.g., 100-110km/h) without excessive strain.
Efficiency & Heat Management Look for >94% peak efficiency in the 20-80% load range (typical for city driving). Insist on a liquid-cooled design with a 5-8L/min flow rate and 80-90°C inlet water temperature—this maintains the motor at 70-90°C under peak load. Check for embedded temperature sensors (1-2 per phase) and thermal protection that reduces power output if water exceeds 95°C.
Mechanical Integration Match the motor’s flange (e.g., C-face 132S) and shaft (e.g., 28mm diameter, 50mm length, keyway) to the Suzuki Carry’s transmission input. A 20-30mm axial length (excluding inverter) ensures space for the cooling pipes. Verify the mounting points align with the engine bay’s existing brackets, and the motor’s weight (≤45kg) avoids overloading the front suspension.
Inverter & Control The inverter must support 144V DC input and 45kW peak output. Confirm it uses a high-frequency IGBT module (e.g., 8kHz carrier frequency) to reduce motor noise. It should have CAN communication (e.g., CAN 2.0B) to interface with the BMS and vehicle controller, enabling features like torque control and fault diagnosis. A built-in DC-DC converter (12V/10A) is ideal for powering vehicle electronics.
Safety & Protection Ensure the motor has IP67 ingress protection (dust/water resistance) and Class H (180°C) insulation to withstand harsh conditions. The inverter should have short-circuit, over-temperature, and over-current protection. Validate the system’s isolation resistance (>100MΩ) and dielectric strength (1kV AC for 1 minute) to prevent electrical hazards.
Auxiliary Components Include a 5-7L/min water pump, a 3-5L coolant reservoir, and aluminum radiators (with a 12V fan) for cooling. Use silicone hoses (ID 10-12mm) with clamps for durability. A coolant mix (50% distilled water + 50% ethylene glycol) prevents freezing and corrosion. Add a pressure relief valve (0.8-1.2 bar) to the system.
Testing & Validation After installation, conduct a no-load test (verify rotation direction and noise) and a load test (run at 25kW for 30 minutes, monitoring water/motor temperatures). Perform a hill-climb test (30% gradient) to validate peak torque. Finally, drive for 100km to validate system stability and energy consumption.
By carefully evaluating these parameters, you’ll ensure the motor system delivers optimal performance while maintaining the Suzuki Carry’s compact size and reliability.
