With the rapid development of industrial automation and flexible manufacturing, high-end mobile collaborative robots integrating Autonomous Guided Vehicles (AGVs) and robotic arms have become core equipment for intelligent logistics and precision operation. Their power drive system, serving as the "dynamic core" of the entire machine, needs to provide robust, efficient, and precise power conversion and control for critical loads such as traction motors, joint servo drives, and various sensors. The selection of power MOSFETs directly determines the system's power density, dynamic response, thermal performance, and operational reliability. Addressing the stringent requirements of mobile collaborative robots for high torque, high precision, safety, and endurance, this article centers on scenario-based adaptation to reconstruct the power MOSFET selection logic, providing an optimized solution ready for direct implementation.
I. Core Selection Principles and Scenario Adaptation Logic
Core Selection Principles
Voltage & Current Margin: For motor drive buses (typically 48V, 72V, or higher) and auxiliary power rails (12V/24V), MOSFET voltage/current ratings must have sufficient safety margins to handle regenerative braking spikes, load transients, and ensure long-term reliability.
Ultra-Low Loss for Efficiency: Prioritize devices with very low on-state resistance (Rds(on)) and optimized gate charge (Qg) to minimize conduction and switching losses, crucial for battery runtime and thermal management.
Package for Power & Thermal: Select packages like TO247, TO220, TO263 based on power level and thermal design constraints, balancing high current capability with effective heat dissipation.
Robustness & Reliability: Must withstand vibration, frequent start/stop cycles, and potential overloads in industrial environments, featuring strong avalanche capability and stable parameters.
Scenario Adaptation Logic
Based on the core power train of a mobile collaborative robot, MOSFET applications are divided into three main scenarios: Traction Motor Drive (High-Current Core), Robotic Arm Joint Drive (Medium-Power Precision), and Main Power Distribution & Safety Isolation (System Reliability). Device parameters and characteristics are matched accordingly.
II. MOSFET Selection Solutions by Scenario
Scenario 1: Traction Motor Drive (48V/72V System, High Current) – Dynamic Core Device
Recommended Model: VBP1606S (Single-N, 60V, 150A, TO247)
Key Parameter Advantages: Utilizes advanced Trench technology, achieving an ultra-low Rds(on) of 5mΩ at 10V Vgs. A continuous current rating of 150A easily meets the high torque and peak current demands of AGV traction motors.
Scenario Adaptation Value: The TO247 package offers excellent thermal performance for heat dissipation. Ultra-low conduction loss maximizes battery energy utilization and reduces heatsink requirements. Low switching loss supports high-frequency PWM for smooth and quiet motor operation, enhancing control precision.
Applicable Scenarios: High-current H-bridge or three-phase inverter drives for traction motors in 48V/72V mobile platforms.
Scenario 2: Robotic Arm Joint Servo Drive (Medium Power, Frequent Switching) – Precision Control Device
Recommended Model: VBP16R87SFD (Single-N, 600V, 87A, TO247)
Key Parameter Advantages: Features Super Junction Multi-EPI technology, offering a low Rds(on) of 26mΩ at 10V Vgs alongside high voltage rating (600V). The 87A current rating suits medium-power servo drives.
Scenario Adaptation Value: The high voltage rating provides ample margin for bus voltage spikes during regenerative braking from joint motors. The good Rds(on)/Qg trade-off ensures low loss during frequent acceleration/deceleration and positioning cycles, crucial for joint efficiency and responsiveness. The TO247 package facilitates thermal management.
Applicable Scenarios: Servo drives for 6-7 axis robotic arm joints, especially in systems with higher bus voltages or demanding dynamic performance.
Scenario 3: Main Power Distribution & Safety Isolation – System Reliability Device
Recommended Model: VBMB2157N (Single-P, -150V, -30A, TO220F)
Key Parameter Advantages: P-Channel MOSFET with -150V Vds rating and Rds(on) of 65mΩ at 10V Vgs. The -30A current capability is suitable for main power path control.
Scenario Adaptation Value: P-MOSFET simplifies high-side switch design for main battery distribution or module isolation (e.g., isolating the robotic arm power from the AGV base). The -150V rating offers good margin. The TO220F insulated package enhances safety and simplifies mounting. Enables centralized power management, emergency stop (E-stop) cutoff, and intelligent power sequencing for different subsystems.
Applicable Scenarios: Main battery disconnect switch, safety isolation relays, and high-side switching for high-power auxiliary subsystems.
III. System-Level Design Implementation Points
Drive Circuit Design
VBP1606S / VBP16R87SFD: Require dedicated high-current gate driver ICs with adequate peak current capability. Optimize gate loop layout to minimize inductance. Use Kelvin source connections if possible for VBP1606S.
VBMB2157N: Can be driven by a level-shifted signal from system controllers or safety PLCs. Ensure fast turn-off for safety functions.
Thermal Management Design
Staggered Thermal Strategy: VBP1606S and VBP16R87SFD likely require dedicated heatsinks, possibly forced air cooling. VBMB2157N may rely on chassis mounting or a smaller heatsink.
Derating for Mission Profiles: Apply significant derating based on worst-case operational profiles (e.g., simultaneous peak loads, high ambient temperature in factories). Maintain junction temperature well within limits under all conditions.
EMC and Reliability Assurance
EMI Suppression: Implement snubber circuits across MOSFET drain-source in motor drives. Use low-inductance busbar design for the traction inverter. Proper shielding and filtering for encoder/sensor lines.
Protection Measures: Implement comprehensive protection: desaturation detection for motor drive MOSFETs, fast-acting fuses on main power paths, TVS diodes for voltage clamping, and robust ESD protection on all control interfaces. Redundancy or monitoring for the safety isolation switch (VBMB2157N).
IV. Core Value of the Solution and Optimization Suggestions
The power MOSFET selection solution for high-end mobile collaborative robots proposed in this article, based on scenario adaptation logic, achieves optimized coverage from high-power propulsion to precision motion control and system-level power management. Its core value is mainly reflected in the following three aspects:
Maximized Power Efficiency and Runtime: By selecting ultra-low Rds(on) devices like VBP1606S for the highest power loss stage (traction) and efficient SJ-MOSFETs like VBP16R87SFD for joint drives, system-wide conduction and switching losses are minimized. This directly extends battery-operated runtime, reduces thermal stress, and allows for either a smaller battery pack or longer work cycles, enhancing operational economy.
Enhanced System Performance and Safety: The solution balances high dynamic performance (enabled by fast-switching, low-loss MOSFETs) with system-level safety and reliability. The use of a robust P-MOSFET (VBMB2157N) for main power control enables clean and reliable safety isolation, a critical requirement for collaborative robots working in human environments. This architecture supports safe torque-off (STO) and other functional safety features.
Optimal Balance of Performance, Robustness, and Cost: The selected devices represent mature, high-performance technologies (Trench, Super Junction) in industry-standard packages, ensuring supply stability and cost-effectiveness compared to nascent technologies like SiC for the entire power chain. The careful matching of device capability to specific scenario needs avoids over-engineering while guaranteeing robust operation under demanding industrial conditions.
In the design of the power drive system for high-end mobile collaborative robots, power MOSFET selection is a cornerstone for achieving high efficiency, dynamic performance, safety, and reliability. The scenario-based selection solution proposed in this article, by accurately matching the distinct requirements of traction, actuation, and power management, and combining it with rigorous system-level design practices, provides a comprehensive, actionable technical reference for robot developers. As robots evolve towards higher payloads, longer endurance, and closer human collaboration, power device selection will increasingly focus on integration with advanced control algorithms and functional safety concepts. Future exploration could involve the application of SiC MOSFETs (like the listed VBP165C30-4L) in ultra-high efficiency or high-switching-frequency segments, and the development of intelligent power modules integrating sensing and protection, laying a solid hardware foundation for the next generation of smarter, safer, and more capable collaborative robots.

Detailed Topology Diagrams