Multi-inverter module paralleling frequency conversion device for transmission system and control policy

Abstract

The invention relates to a multi-inverter module paralleling frequency conversion device for a transmission system and a control policy. The device comprises a rectifier, inverters, a braking device, a cooling system, a protection device, an interface and the like, and is characterized in that an inverter paralleling structure realizes a relatively high power factor; through the parallel connection of multiple rectifying modules and the parallel connection of multiple inversion units, the output capacity of the inverters is increased, and the input / output harmonic waves are reduced; a control box drives a motor to operate by controlling the work of a frequency converter; and a fuse group and control power supply perform fault protection on the system and provide power to each part. In the control policy, a motor driving mode that master and slave modules perform hierarchical control is adopted; as the master control module synchronizes the slave control module, the problem of difficult same-frequency and same-phase output of multiple inverters in the case of motor load is solved; by monitoring the current of each inversion module (multiple inversion modules) and dynamically adjusting the output of each inversion module, the key technology of realizing homogeneous flow of the outputs of multiple paralleling inversion modules is broken through, and an inverter paralleling frequency conversion and speed regulation control method with relatively high static and dynamic performance is realized; and high power of the frequency conversion device with multiple paralleling inversion modules for the transmission system is realized.

Description

technical field [0001] The invention relates to a parallel frequency conversion device and a control strategy, in particular to a multi-inverter module parallel frequency conversion device for a transmission system and a related control strategy. Background technique [0002] The large-capacity propulsion inverter is one of the core equipment of the electric propulsion system, and the development technology of the large-capacity propulsion inverter is not yet mature in China, and there is no ability to develop a large-capacity marine propulsion inverter by itself. The technical approaches to expand the inverter capacity mainly include: multi-phase technology, multi-level technology and inverter parallel operation technology. Among them, the multi-phase technology needs to solve the control strategy problem of the multi-phase propulsion motor, and the system is more complicated; the multi-level technology increases with the increase of the number of levels, and its topology s...

AI Technical Summary

Problems solved by technology

[0011] Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention constructs a four-inverter module parallel output speed regulation control system with motor load, which solves the problem of four inverters with the same frequency and phase when the motor is loaded. The problem of difficult output has realized the control method of inverter parallel frequency conversion speed regulation with higher static and dynamic performance

Images