Control System - Delta Electronics MVF2000 Series Product Manual

Each power cell has an independent cell control board and drive board, wherein the cell
control board receives the PWM signal transmitted by the main control system by means of
optical fiber to control the IGBT. Simultaneously, the status information of each power cell is
fed back to the main control system by the cell control board by means of optical fiber. The
drive board is used to drive the IGBT and feedback the failure signal of the IGBTs to the cell
control board, such as short circuit protection.

2-2-3 Control system

The structure diagram of the control system is as shown in Fig. 2-13.
The main functions of the main control system comprise: digital input & output, analog
input & output, PWM control signal generation of each power cell, encoding and decoding of
the control signal, system self-diagnosis, delivery of various implementation instructions,
collection and handling of various failures, communication with external systems, and etc.
A PLC (Programmable Logic Controller) is used for the logical processing of the internal
switching signals, site operation signals and status signal of medium voltage drive, thus
enhancing the flexibility at the site application. The MVF2000 medium voltage drive products
uses a high-quality PLC to accomplish the input & output MVD signal control, protection and
interlocking, external failure detection, communication with the main control system and
control of the human-machine interface.
The HMI (Human-machine interface) is based on a high definition liquid crystal
touch-type screen. It is easy to operate and is mainly used to set functional parameters,
display and record the system status, operation status and failures through the connection to
Fig. 2-13 Structure diagram of the control system
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