China Suppliers Factory PUMBAA 3-in-1 Electric Vehicle Power Supply OBC+DCDC+PDU for Efficient Charging Solutions
Features of PUMBAA Electric Vehicle power supply 2*DCAC+DCDC+PDU 4-in-1 CDU Unit
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
Characteristics of OBC+DCDC+PDU 3-in-1 CDU Unit
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.
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.
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.
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.
Main Components of Vehicle power supply Conversion & Distribution Unit(CDU)
OBC (On-Board Charger)
Mainly converts single-phase AC or three-phase AC into DC to charge the vehicle power battery.
DC/DC Converter
Mainly converts the high-voltage DC power output from the power battery into low-voltage DC power to supply power to the low-voltage power equipment of the vehicle.
PDU (Power Distribution Unit)
High-voltage power distribution unit, which is a centralized power distribution scheme for new energy vehicles, with compact structure design, convenient wiring layout and convenient maintenance.
Benefits of Electric Vehicle power supply Conversion & Distribution Unit(CDU)
(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.
Conform with EU standard
Support vehicle-to-vehicle charging (V2V)
Support vehicle-to-load charging (V2L)
All-automotive-grade device design
Bidirectional power conversion
Support UDS diagnosis
Support OTA upgrade and rollback
Applicable to BEV, PHEV, REEV, 2.5/3.5T
Minivans, Minitrucks, passenger cars, commercial vehicles, buses, professional vehicles and other types of new energy vehicles
Specification of Electric Commercial Vehicle power supply
| DCDC | Input characteristics | High Voltage | 200-450V |
| Low pressure | 12V | ||
| Output characteristics | Power | Rating：1.5kW Peak：1.8kW | |
| Output voltage | 14VDC | ||
| Output Current | Rating：108A Peak：128A | ||
| OBC | Input characteristics | High Voltage | 85~264VAC |
| Low pressure | 12V | ||
| Output characteristics | Power | 3.3KW | |
| Output voltage | 200~450VDC | ||
| Maximum output current | 10A | ||
| PDU | Function 1 | Batteries (standard) | |
| Function 2 | Main Drive (standard) | ||
| Function 3 | Electric air conditioner (standard) | ||
| Function 4 | PTC (standard) | ||
| System characteristics | Operating temperature | -40~80℃ | |
| Cooling mode | Water cooling | ||
| Size | 189W×281D×121H（mm） | ||
| Weight | About 10 kg | ||
| Protection level | IP67 | ||
Applications
Passenger car
2.5T Electric Minivan
3.5T Electric Minivan
Electric Vehicle Power Conversion and Distribution Systems: From Energy Inlet to End Application
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.
（Appearance diagram of high voltage power distribution box PDU）
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.
(Bidirectional OBC Application Scenarios/双向车载充电机的应用场景)
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).
(Comparison of AC and DC charging)
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."
Frequently Asked Questions (FAQ)
What are the main functions of a 3-in-1 or 4-in-1 CDU Unit in an electric vehicle?
The Conversion & Distribution Unit (CDU) integrates key power supply components including the On-Board Charger (OBC), DC/DC converter, and Power Distribution Unit (PDU). It converts AC power from the grid to charge the high-voltage battery (OBC), steps down high-voltage battery power to low-voltage power for vehicle electronics (DC/DC), and safely distributes high-voltage energy throughout the vehicle (PDU).
How does an integrated CDU design benefit EV range and spatial efficiency?
By integrating multiple components into a single unit, the system achieves a 15% to 30% reduction in weight and a 20% to 40% reduction in volume. This integration improves overall vehicle body space utilization by over 50%, lowers the vehicle's center of gravity for better handling, and shortens high-voltage wiring, which minimizes energy transmission loss and increases driving range.
Does the PUMBAA CDU support bidirectional charging like V2L and V2G?
Yes, the PUMBAA CDU supports bidirectional power conversion. It is designed to meet multi-scene requirements including Vehicle-to-Load (V2L) for powering household appliances, Vehicle-to-Grid (V2G) for supplying power back to the electrical grid, and Vehicle-to-Vehicle (V2V) charging.
What vehicle types are compatible with these power conversion and distribution systems?
These units are highly adaptable and designed for BEVs (Battery Electric Vehicles), PHEVs (Plug-in Hybrid Electric Vehicles), and REEVs (Range Extended Electric Vehicles). They are suitable for 2.5T/3.5T minivans, minitrucks, passenger cars, commercial vehicles, buses, and other professional new energy vehicles.
What safety and protection mechanisms are built into the CDU?
The system features an automotive-grade design compatible with ASIL standards. It integrates multiple protection functions including EMC (Electromagnetic Compatibility), voltage resistance, insulation, vibration resistance, and electrical overload protection. It also features a liquid-cooled system for fast heat dissipation, dustproofing, and has an IP67 protection rating.