Frequency Converter in Pump Control Systems
The frequency converter (FC) in pump installation control systems not only contributes to energy savings but also solves many technological challenges. An important function is the alternating operation of pumps, which allows for the even wear of equipment using cascade control. Altivar Process ATV600 drives help optimize energy consumption and also provide monitoring capabilities.
Cascade Control Systems
Cascade systems are used in several pump communications. Typically, such systems are used in water supply and water consumption, where multiple pumps can be regulated depending on the control mode:
Operation of the Frequency Converter with One Pump
In cases where a single pump is used, the frequency converter provides basic control of the pump installation through one drive. The Altivar Process ATV600 drive is capable of controlling up to 5 pumps.
Multi-Pump Installations
These systems are used in various applications. The Master drive can control up to 5 follower devices through Multi-Drive Link technology, which allows all sensors to be connected to the Master.
Multiple Frequency-Controlled Drives
In modern installations where continuous operation is required, several drives are involved. This provides more advanced control over the pumps, including drives with variable speed control. Sensors are connected to the Master and Secondary Master.
For systems with multiple pumps controlled by one frequency converter or pumps regulated by multiple drives, the Altivar Process ATV600 drives are connected via a two-port fieldbus module connected to each drive. This can occur by adjusting the speed of the pump connected to the frequency converter or by switching pumps with variable speed.
Types of Control
The type of control allows you to select which process is used for feedback, setpoint, and other related values for PID control. The main types of control include:
- - Pressure: The system operates from a pressure sensor used in pressure control systems.
- - Flow: This type of control is based on operating from a flow sensor and is used in systems to regulate flow.
Speed Control
Traditional Control Mode
This mode is available for Single Drive architecture when there is one variable speed pump. Initially, the variable speed pump is started, and other pumps operate at a constant speed according to the demand.
Distributed Speed Control Mode
This control mode is available for a cascade system with multiple drives. Pumps will turn on and off in sequence, mimicking the ascent and descent of stairs. The last pumps work with variable speed, while others operate at fixed speed.
Advanced Speed Control Mode
This mode is available for operation with multiple drives where the pumps operate in sequence and at the same speed.
For further familiarization with the capabilities of multi-pump systems, we recommend reading the manufacturer's guide.