PCD230A ABB 励磁系统

该励磁系统是一种以晶闸管为基础的静态系统，适用于大中型同步机。其使用电源为50Hz、60 Hz或162/3 H，适用于最高可达10000A的磁场电流。该励磁系统主要用于发电厂中发电机励磁。
该励磁系统能够通过以微处理器为基础的单通道或双通道调节器以及可选配的附加后备电流调节器，进行自动电压调节。
该励磁系统能够全面集成于更高级别的分级控制系统中。静态励磁系统(SES)基于经年累月的专业知识以及久经考验的技术。它包括微处理器控制器，采用了最先进的印刷电路板技术以及高效半导体电路技术。数字式自动电压调节器(AVR)模块是一个多功能电力电子控制器。不仅能够控制功率整流器的输出，还具有限制器、监控功能以及供货范围中列出的其它控制电路。受控的功率整流器 DC输出配置有磁场抑制电路，以保护发电机磁场及励磁系统。

PCD230A

励磁系统采用整流器对励磁电流进行控制，从而调节电机机端电压以及同步机的无功功率流。
对于自并励或自励系统，励磁电源来自电机机端。同步机的励磁电流经过励磁变压器和功率整流器。可以将磁场断路器设置在功率整流器的交流侧或直流侧。励磁变压器将发电机的端电压降低成功率整流器所需的输入电压，并隔离电机机端与励磁绕组之间电流，并同时作为功率整流器的整流电抗。功率整流器将交流电流转换成受控制的直流申流。
在启动阶段，起励能量来自辅助电源。只要功率整流器的输入达到 10-20 V，即可控制整流器和控制电子装置，此时起始能量由发电机端子提供。
在与电网同期后，励磁系统可以在AVR 模式下运行，对发电机端电压及无功功率进行调节。它还可以在某个叠加控制模式下运行，即电机的Cos-phi(功率因数)控制或MVAr(无功功率)控制。此外，它还可用于电厂并联点的电压及无功控制。

PCD230A

The excitation system is a static system based on thyristor, which is suitable for large and medium-sized synchro. The power supply is 50Hz, 60Hz or 162/3 H and is suitable for magnetic field currents up to 10000A. The excitation system is mainly used for generator excitation in power plant.
The excitation system is capable of automatic voltage regulation through a microprocessor based single – or dual-channel regulator and an optional additional backup current regulator.
The excitation system can be fully integrated into a higher level hierarchical control system. Static excitation Systems (SES) are based on years of expertise and proven technology. It includes a microprocessor controller and uses the most advanced printed circuit board technology as well as efficient semiconductor circuit technology. The digital Automatic Voltage Regulator (AVR) module is a multifunctional power electronic controller. It not only controls the output of the power rectifier, but also has limiter, monitoring functions and other control circuits listed in the scope of supply. The controlled power rectifier DC output is equipped with a field suppression circuit to protect the generator field and excitation system.
The excitation system uses rectifier to control the excitation current, so as to adjust the terminal voltage of the motor and the reactive power flow of the synchronous machine.
For self-shunt or self-excitation systems, the excitation power comes from the motor side. The excitation current of the synchro passes through the excitation transformer and the power rectifier. The field circuit breaker can be set on the AC or DC side of the power rectifier. Excitation transformer reduces the terminal voltage of the generator to the input voltage required by the successful rectifier, and isolates the current between the motor end and the excitation winding, and at the same time acts as the rectification reactance of the power rectifier. A power rectifier converts an AC current into a controlled DC current.
In the start-up phase, the excitation energy comes from the auxiliary power supply. The rectifier and control electronics can be controlled as long as the input of the power rectifier reaches 10-20 V, at which point the initial energy is provided by the generator terminal.
After the same time with the grid, the excitation system can operate in AVR mode to adjust the generator terminal voltage and reactive power. It can also operate in a superimposed control mode, namely Cos-phi(power factor) control or MVAr(reactive power) control of the motor. In addition, it can also be used for voltage and reactive power control of power plant parallel points.

PCD230A