There are safety risks if students directly do experiments on the high-power devices such as DFIG (Doubly-fed Induction Generator). At the same time, it's not convenient to take fault test directly on the experiment devices. In order to improve the teaching and research work on renewable system, the end user wants to build up a DFIG real-time simulation platform.  

Electromechanical System Real-time Simulation

DFIG is a complicated electromechanical system, which has both electrical components such as motors, back to back converter bridges, and mechanical components such as blades and gearbox. It is a great challenge to simulate both the electrical system and mechanical models together.

ModelingTech Energy Technology Co., Ltd leverage the latest hardware technology and independently developed software StarSim to accomplish power electronics real-time simulation on the NI FPGA hardware. Meanwhile, NI PXI is an open platform, it supports the third party mechanical modeling and simulation software with NI Model Interface Toolkit. So, the whole platform can meet needs of the hybrid electromechanical simulation system very well.

The system diagram is shown as below:

Industrial Communication

In some wind turbine systems, the main control, the yaw control and the pitch control system are communicated with Profibus. Because of the standardized communication requirement in industrial applications, the real-time simulation platform needs to have the corresponding functions. StarSim real-time simulator, based on the NI general hardware platform, supports various industrial communication protocols including Profibus, CAN and 1553B. Therefore, it can meet various demands of industrial applications and can be expanded and upgraded according to the user request.

Modifiable Control Algorithm

Many suppliers can provide doubly-fed system controllers, but generally the control algorithm is not open. However, as a research and teaching platform, the control algorithms are required to be open and easy to modify.

ModelingTech not only has deep technology accumulation in the modeling and real-time simulation, but also has rich experiences in the power electronic system control. ModelingTech can provide the control algorithm to the laboratory for the professors or the graduate students to further modify. 

Real-time Simulation System-based on StarSim and NI platform

The whole system is shown as below, which consists of two parts: the first part is the PXI real-time simulator with FPGA card, which simulates the DFIG system; the second part is CompactRIO (an industrial controller of NI company), working as controller of the DFIG converter. 

Photo of DFIG real-time simulation system

The real-time simulator is connected to the controller through physical I/O, which are exactly the same as the interfaces of real DFIG controller. The controller acquires the signals of voltage, current and encoder from the simulator, then sends PWM signals to control the IGBT on and off according to the execution of control algorithm.