China Suppliers Factory OBC+DCDC+PDU 3-in-1 Power Supply Unit for Electric Vehicles - PUMBAA PPS570

• Highly integrated electrical integration
• Automotive grade design, ASIL compatible
• Support V2L, V2G, V2V and other multi-scene requirements
• Smaller and lighter design, stable technical performance and high efficiency
• Liquid-cooled cooling method, fast heat dissipation, dustproof and low noise
• Multiple protection functions such as EMC, voltage resistance, insulation, vibration and electrical protection
• Allocation and control of high-voltage devices of the whole vehicle through the whole vehicle control unit to ensure the safety performance of each system

• 1 It shortens the arrangement of UVW high-voltage wiring harness, reduces the high cost of using UVW high-voltage wiring harness, and effectively improves the efficiency of motor, controller and reducer after shortening the transmission distance.
• 2 The integrated electric drive assembly achieves 30% weight reduction and 40% volume reduction, which improves its overall body space utilization by more than 50% and provides a strong guarantee for range.
• 3 The vehicle's center of gravity is lowered for better handling performance, which also leads to higher torque capacity and improved efficiency of the electric drive system assembly.
• 4 The reduced size of the electric drive system makes the space layout inside the vehicle more flexible, and the modular design can be extended, which greatly shortens the product development cycle and reduces costs and increases efficiency.

• 1 15% reduction in product weight, 20% reduction in volume, and 5% reduction in low-speed power consumption costs;
• 2 Expandable modular platform, which can be extended to match different models, greatly shortening the product development cycle and saving costs;
• 3 Frequency conversion and multi-vector decoupling control algorithm, effectively improving motor dynamic response and NVH characteristics;
• 4 Perfect fault diagnosis and safety monitoring mechanism, effectively ensure the vehicle high voltage safety, torque safety and high temperature safety.

In the "three-electric system" of electric vehicles (EVs), the power conversion and distribution system serves as the "energy hub" connecting the external grid, power battery, and onboard devices. Through efficient energy conversion and rational distribution strategies, it directly impacts vehicle range, charging efficiency, and power safety. This article analyzes the technical logic and application value of this system from three perspectives: core components, workflow, and technological trends.

I. Core Components of the Power Conversion and Distribution System

The system comprises three key modules: On-Board Charger (OBC), DC/DC Converter, and High-Voltage Power Distribution Unit (PDU), which collaboratively manage the full-chain energy flow from "grid-battery-load."

1. On-Board Charger (OBC):

Function: Converts grid alternating current (AC, 220V/380V) to high-voltage direct current (DC, 300-800V) required by the power battery, serving as the core entrance for external charging.

Key Technologies: Power Factor Correction (PFC) improves grid energy utilization (>95%), while isolation transformers ensure safety between the grid and battery.

2. DC/DC Converter:

Function: Steps down the high-voltage DC from the power battery (e.g., 400V) to low-voltage DC (12V/24V/48V) for onboard devices like lights, air conditioners, and instrument panels.

Design Focus: Adopts high-frequency switching technologies (e.g., LLC resonant topology) to reduce losses and supports multi-channel outputs for complex power demands.

3. High-Voltage Power Distribution Unit (PDU):

Function: Acts as the "distribution center" for high-voltage energy, allocating DC power from the battery to high-voltage components (e.g., motor controllers, charging interfaces, air conditioning compressors) while integrating overcurrent and short-circuit protection.

II. Workflow of the Power Conversion and Distribution System

The system operates in two modes: charging mode (grid-to-battery) and discharging mode (battery-to-loads), covering full-scenario energy flow from external charging to onboard power usage.

1. Charging Mode (Grid → Battery):

Household/public chargers output AC (220V/380V) → OBC rectifies AC to high-voltage DC (e.g., 800V) via PFC circuits → PDU distributes power to the power battery’s charging interface → The Battery Management System (BMS) controls charging current and voltage to complete energy storage.

2. Discharging Mode (Battery → Loads):

The power battery outputs high-voltage DC (e.g., 800V) → PDU allocates power to the motor controller (for driving motors) or DC/DC converter (for low-voltage devices) → The motor controller converts DC to three-phase AC (AC) to drive the motor, while the DC/DC converter steps down high-voltage DC to low-voltage DC for onboard devices.

III. Technological Trends: Integration, Bidirectionality, and Intelligence

As EVs evolve toward "longer range and higher intelligence," power conversion and distribution systems are undergoing three key upgrades:

1. Integrated Design:

"Two-in-One" Integration (OBC + DC/DC): Reduces component count, size, and cost (e.g., Tesla Model 3’s integrated OBC and DC/DC module).

"Three-in-One" Integration (OBC + DC/DC + PDU): Further improves system efficiency (e.g., BYD ePlatform 3.0’s "eight-in-one" drive system).

2. Bidirectional Functionality:

Bidirectional OBC supports "V2L (Vehicle to Load)" and "V2G (Vehicle to Grid)": It not only charges the battery but also converts battery energy back to AC for onboard appliances (e.g., refrigerators) or external power supply (homes/grids).

3. Intelligent Control:

Integrates AI algorithms and IoT technologies to monitor battery status (SOC, SOH), grid load, and usage scenarios (e.g., highway/city) in real time, dynamically adjusting conversion strategies (e.g., prioritizing power during fast charging, reducing losses at low speeds).

Conclusion

The electric vehicle power conversion and distribution system is a critical enabler of the "three-electric system." Through the collaborative work of OBC, DC/DC, and PDU, it achieves efficient energy flow from the grid to the battery and onward to onboard devices. With advancements in integration, bidirectionality, and intelligence, this system will further reduce energy consumption, enhance safety, and drive EVs toward "longer range and higher intelligence."