Elevator systems are the backbone of modern buildings, ensuring smooth vertical transportation for residents, employees, and goods. At the heart of these systems lies the elevator inverter, a critical component that controls motor speed, energy efficiency, and ride comfort. With advancements in technology, the debate between open loop and closed loop systems has evolved, leading to the rise of open loop and close loop integrated elevator inverters. This article dives deep into the differences, benefits, and applications of these systems, focusing on why the integrated elevator inverter is becoming the gold standard for modern buildings.
Understanding Open Loop and Closed Loop Elevator Inverters
What Is an Open Loop System?
An open loop elevator inverter operates without real-time feedback from the motor. It relies on predefined parameters to control speed and torque, making it simpler and more cost-effective. However, its lack of feedback can lead to inefficiencies in dynamic environments, such as sudden load changes or varying floor heights.
Pros of Open Loop Systems:
Lower initial cost.
Simpler installation and maintenance.
Suitable for applications with consistent load demands.
Cons of Open Loop Systems:
Reduced precision in speed control.
Vulnerable to motor slip and torque fluctuations.
Limited adaptability to complex building requirements.
What Is a Closed Loop System?
A closed loop vector VVF inverter uses real-time feedback from encoders or sensors to adjust motor performance dynamically. This ensures precise speed control, better torque management, and enhanced energy efficiency. It’s ideal for high-rise buildings, heavy cargo elevators, and applications requiring strict safety standards.
Pros of Closed Loop Systems:
Superior speed and torque accuracy.
Adaptable to variable loads and complex environments.
Enhanced safety features like overspeed protection and door preopen.
The Rise of Integrated Solutions: Open Loop and Close Loop Integrated Elevator Inverter
The integrated elevator inverter combines the simplicity of open loop systems with the precision of closed loop technology. This hybrid solution allows users to switch between modes via parameter settings, making it adaptable to diverse building needs. For example, a villa elevator might prioritize cost-effectiveness (open loop), while a commercial high-rise demands precision (closed loop).
Key Advantages of Integrated Inverters
Flexibility: Switch between open loop and closed loop vector VVF inverter modes effortlessly.
Cost Efficiency: Eliminate the need for separate systems, reducing hardware and maintenance expenses.
Future-Proofing: Compatible with both asynchronous AC induction motors and permanent magnet synchronous motors (PMSM).
Advanced Safety: Features like brake contactor control, overspeed protection, and motor overheat detection.
Technical Features of Modern Integrated Elevator Inverters
The IFIND Open Loop and Close Loop Integrated Elevator Inverter exemplifies cutting-edge innovation. Below are its standout features:
1. Dual Motor Compatibility
Supports asynchronous AC induction motors and permanent magnet synchronous motors (PMSM).
Multiple encoder interfaces (AB, ABZ, Endat 1313, Sin/Cos 1387) for gearless and geared motors.
2. Enhanced Ride Comfort
Multi-segment S-curve acceleration/deceleration.
Four groups of acceleration/deceleration time settings.
Pre-torque compensation for smooth starts.
3. Emergency Power Management
Supports 48V battery backup for emergency evacuation during power outages.
Compatible with industry UPS and home UPS software.
4. Robust Build Quality
High-grade components: STARPOWER/Infineon IGBTs, Rubycon capacitors, and Delta electronics.
IP21 enclosure with lightning protection and EMC compliance.
5. Simplified Commissioning
RJ45 interface for external operation panels.
Motor auto-tuning (static and complete modes).
Data Analysis: Comparing Open Loop, Closed Loop, and Integrated Systems
To help building owners make informed decisions, we’ve analyzed critical metrics across inverter types:
Parameter
Open Loop
Closed Loop
Integrated Inverter
Cost
Low
High
Moderate
Precision
Moderate
High
Adjustable (High/Moderate)
Motor Compatibility
Asynchronous Only
PMSM & Asynchronous
Both + Multi-Encoder Support
Safety Features
Basic
Advanced
Advanced + Customizable
Installation Complexity
Low
High
Moderate
Energy Efficiency
70-80%
90-95%
85-95% (Mode-Dependent)
Technical Specifications of IFIND Integrated Inverters
The IFIND SD320L series offers scalable solutions for diverse buildings. Below is a breakdown of key models:
Voltage Classes and Drive Models
Model
Voltage
Power (kW)
Output Current (A)
Dimensions (HxWxD mm)
SD320L-3.7KW-2
220V
3.7
13
250x160x183
SD320L-7.5KW-4
380-480V
7.5
18
320x220x183
SD320L-15KW-4
380-480V
15
33
320x220x183
Braking and Power Management
Model
Braking Resistor (Ω)
Battery Backup
Overload Capacity
SD320L-5.5KW-2
≥45
48V Supported
150% for 60s, 180% for 3s
SD320L-11KW-4
≥43
48V Supported
150% for 60s, 180% for 3s
Choosing the Right Inverter for Your Building
1. Residential and Villa Elevators
Priority: Cost-effectiveness, quiet operation.
Recommended System: Integrated inverter in open loop mode for low to medium traffic.
Customization: Demand for UPS compatibility and battery backups in regions with unstable grids (e.g., Saudi Arabia’s growing market).
Final Thoughts
The open loop and close loop integrated elevator inverter represents the pinnacle of elevator control technology. By merging flexibility, precision, and cost-efficiency, it addresses the shortcomings of traditional systems. Whether you’re managing a villa, a commercial tower, or an industrial facility, this hybrid solution ensures optimal performance tailored to your needs. For builders and engineers attending events like the Saudi Exhibition, exploring IFIND’s SD320L series could unlock new opportunities in vertical transportation.
In a world where adaptability is key, the integrated elevator inverter isn’t just an option—it’s the future.
