———— PULS Poole Power CT5.241 & PAS395 for Wind Turbine Pitch Control System
[Edit Profile]: This article describes the power supply solutions for the wind turbine pitch control system provided by Poole. The system consists of a 24Vdc DC/DC power supply CT5.241 (or CT10.241) and a supercapacitor charger PAS395. The article analyzes the system requirements and implementation methods, and gives the performance parameters of the main products.
[Summary]: The wind turbine-generator electric control part contains the following parts: main control system, pitch control system and converter. Pitch control system, as the name suggests, is used to control and change the angle of blades (blade) to achieve optimal wind power at different wind speeds; when wind conditions are rather harsh, it controls the angle of blades to make wind power The machine can operate safely and reliably to protect the fan. In addition, the pitch control system must be able to ensure that the blade feather is still controlled to protect the fan when the grid is disconnected or other faults occur.
[Key words]: PULS Poole, wind power generation, pitch control system, backup power supply, battery
Pitch control system is to achieve fan power control by changing the blade angle of attack. Specifically, the pitch angle of the blade is changed by rotating the slewing bearing by the pitch drive motor installed between the blade and the hub, thereby controlling the lift of the blade to achieve the purpose of controlling the torque and power acting on the blade of the wind wheel. Pitch control system as a basic control system for wind turbines has the following three main tasks:
1. Adjust blade angle of attack to obtain proper power;
2. Control the rotation speed of the blade at a certain speed by adjusting the blade angle;
3. When the fan has other faults, use a backup power source as a power to drive the pitch motor to safely feather the blades.
From this it can be seen that controlling the motor to rotate the blade is the drive of the motor. The components are as follows:
Fig. 1 Schematic diagram of the pitch motor drive
The four components in Figure 1 above (except for the pitch motor) and their respective roles:
1. Rectifier - The three-phase AC voltage transmitted to the pitch control system through the slip ring is converted into a DC voltage, which provides the input voltage to the inverter at the rear stage;
2. Inverter - variable frequency drive pitch motor to complete the blade angle of attack control;
3. Backup power supply - When the grid voltage drops or is powered off, or when other safety faults occur in the fan, a backup power supply (common lead-acid battery pack or super capacitor bank) is required to provide the DC voltage to the inverter to achieve blade safety. Paddles to achieve safe operation;
4. Charger - Charge the backup power supply when the grid voltage is normal.
In addition to the above four important components, the pitch control system also has a 24Vdc control power supply that provides 24Vdc working voltage for PLC, digital input/output, control relays, and induction switches in the pitch changer.
In general, 24Vdc operating voltage is achieved through the following methods:
Fig. 2 24Vdc power supply scheme in pitch control system
The DC/DC is directly connected to the backup power supply in the pitch changer and the backup power supply DC voltage is converted to 24Vdc to provide power to the load. The point to note when selecting this DC/DC power supply is that its shutdown-down voltage is lower than the turn-off voltage of the drive, so that safety control can be achieved and the blade can be safely feathered.
In this scheme, PULS Poole can provide customers with 24Vdc power of different power, to achieve high reliability 24V power solutions, especially the DC/DC power supply CT series (including CT5.241 and CT10.241), its main The parameters are as follows:
- AC/DC conversion or DC/DC conversion
- DC input range: 370~780Vdc, Shut-down voltage is 260Vdc
-24Vdc output with 24V/5A and 24V/10A power supplies
- Width only 40mm (CT5.241) and 62mm (CT10.241)
- Efficiency up to 90.2% (CT5.241) and 92.9% (CT10.241)
- 120% continuous overload capacity at ambient temperature <45°C
- Active input surge current suppression
- Allowable operating temperature range: -25°C...+70°C (requires derating for >60°C)
-Allowable working altitude: <6 000m (>2 000m derating required)
- DIN rail mounting, side mounting, or wall screw mounting
-CE/UL/GL certification
-3 year warranty
In addition to providing 24Vdc power supply, PULS Poole can also provide its highly reliable supercapacitor charger PAS395 in the pitcher with super-capacity backup power supply. The charger has the following features:
- Single phase AC input, input range: 176~264Vac
- Charge end voltage adjustable from 360 to 460Vdc
-Charging current >2.5A, can be filled with 450V/2F capacitive modules in 6 minutes
- Allowable operating temperature range: -40°C...+65°C
-Allowed working altitude: <6 000m without derating
- Light weight, adapt to strong vibration and shock
- Built-in smart fan, suitable for any mounting orientation
- Conversion efficiency up to 94%
- Intelligent charge management to further reduce heat dissipation
- Mean time between failures (MTBF) over 1 million hours
- Service life expectancy exceeding 10 years
- Pluggable, snap-in terminals
- Complete remote monitoring and fault diagnosis
-CE/GL certification
With the increasing power level of single wind turbines and offshore wind turbines gradually becoming a trend, there are more and more applications of super capacitors as back-up power supplies for pitch control systems. Because of the advantages of using a lead-acid battery as a backup power source, the advantages of using a supercapacitor are: First, it can tolerate a wide range of operating temperatures without heating measures; Second, longer service life; Third, low maintenance costs Fourth, small size and light weight.
PULS Poole offers a DC/DC power supply CT5.241 (or CT10.241) with a 24Vdc output and a supercapacitor charger PAS395, which provides a highly reliable power supply solution for your pitch control system.