Fuji EVL31-050 PIM: An Integrated CIB Solution for Compact Motor Drives
Fuji Electric EVL31-050 Power Integrated Module (PIM)
Integrated CIB Solution for Compact Motor Drives
The Fuji Electric EVL31-050 is a Power Integrated Module (PIM) that consolidates a complete three-phase motor drive power stage into a single, compact component. This module’s primary engineering value lies in its high level of integration, incorporating a converter, inverter, and brake (CIB) circuit. This architecture significantly simplifies the design and assembly of low-power motor control systems.
- Core Specifications: 600V / 5A (Inverter) | 600V / 50A (Converter)
- Key Advantages: Drastically reduces PCB footprint and component count. Includes an integrated NTC thermistor for direct thermal feedback, simplifying over-temperature protection circuits.
- Design Application: This module provides a direct answer for engineers needing a complete power stage for fractional horsepower AC drives without complex discrete component sourcing.
Download Official Datasheet (PDF)
Technical Analysis of the EVL31-050 Architecture
The defining feature of the EVL31-050 is its CIB (Converter-Inverter-Brake) topology. This design integrates the three fundamental blocks of a variable frequency drive into one package. The converter section consists of a three-phase diode bridge for rectifying AC line voltage. The inverter section features six 5th-generation IGBTs with corresponding freewheeling diodes (FWDs) to synthesize a three-phase AC output for the motor. Finally, the integrated brake chopper IGBT allows for the management of regenerative energy during motor deceleration, a critical function in dynamic applications. This integration streamlines the power stage layout, reduces parasitic inductance, and accelerates the development cycle.
Integrated Thermal Monitoring for Enhanced Reliability
A key feature for system reliability is the built-in NTC (Negative Temperature Coefficient) thermistor. This component provides a direct, real-time indication of the module’s substrate temperature. The NTC acts like a built-in thermometer for the module’s core, giving the control system a direct reading to anticipate and prevent overheating events. By monitoring the NTC’s resistance, a microcontroller can trigger alarms or shut down the drive before the IGBTs reach their maximum junction temperature of 150°C. This eliminates the need for external temperature sensors on the heatsink, simplifying both mechanical and electrical design.
Optimized Application Scenarios
The specific characteristics of the EVL31-050 make it a strong candidate for several applications:
- Low-Power AC Motor Drives: The 5A inverter rating is well-suited for controlling three-phase AC motors under 1 kW, such as those in small conveyor systems, pumps, and fans.
- Servo Drives and Actuators: The integrated brake chopper is essential for servo applications that require rapid and precise deceleration, where it safely dissipates regenerative energy.
- Appliance Motor Control: Its compact footprint and all-in-one nature are advantageous in space-constrained appliances like advanced washing machines or HVAC systems.
- Small Robotics: In robotic arms or automated guided vehicles (AGVs), the high power density and simplified assembly process enabled by this PIM are highly beneficial.
This module is an optimal match for sub-1kW motor drive systems where board space, component count, and design simplicity are primary engineering constraints.
Key Specifications of the EVL31-050
| Parameter | Value |
|---|---|
| Inverter Part | |
| Collector-Emitter Voltage (Vces) | 600V |
| Collector Current (Ic) | 5A (DC, at Tc=80°C) |
| Collector-Emitter Saturation Voltage (Vce(sat)) | 2.5V (Typ) / 3.0V (Max) at Ic = 5A |
| Converter Part (Diode Bridge) | |
| Repetitive Peak Reverse Voltage (VRRM) | 600V |
| Average Forward Current (IF(AV)) | 50A |
| Thermal and Mechanical Characteristics | |
| Operating Junction Temperature (Tj) | +150°C |
| Isolation Voltage (Viso) | 2500V (AC for 1 minute) |
| NTC Thermistor R25 | 5 kΩ ±3% |
Engineer FAQ
Q: How is the integrated NTC thermistor used for over-temperature protection?
A: The NTC thermistor’s resistance decreases predictably as the module’s temperature rises. A control circuit, typically connected to a microcontroller’s ADC, monitors this resistance. Based on the resistance-temperature curve provided in the datasheet, the controller can calculate the module’s internal temperature and trigger a fault condition or power reduction if it approaches the 150°C maximum limit.
Q: What are the recommended mounting torque specifications for this module?
A: According to the datasheet, the recommended torque for the M4 mounting screws is 1.27 to 1.67 Nm. Applying the correct torque is crucial for ensuring proper thermal management and mechanical stability.
Q: What is the primary function of the brake chopper circuit?
A: When a motor decelerates rapidly, it acts as a generator, sending electrical energy back to the DC bus. The brake chopper diverts this energy to an external braking resistor, preventing the DC bus voltage from rising to dangerous levels and protecting the module and other components.
Q: Is it possible to use only the inverter or converter section of the EVL31-050?
A: Yes, the module’s terminals provide separate access to the converter output and inverter input. An engineer could, for example, supply the inverter section from a separate DC source and leave the converter section unused, or use the rectifier bridge to power a different circuit.
Enabling Efficient Power Stage Design
The EVL31-050 PIM provides a robust, functionally complete power stage for low-power motor control. Its integrated CIB design, combined with built-in thermal sensing, allows engineering teams to reduce system complexity, minimize PCB area, and improve the overall reliability of their final product. This module directly addresses the need for faster development cycles in cost-sensitive industrial and appliance applications.