該勵磁系統(tǒng)是一種以晶閘管為基礎(chǔ)的靜態(tài)系統(tǒng)，適用于大中型同步機。其使用電源為50Hz、60 Hz或162/3 H，適用于最高可達10000A的磁場電流。該勵磁系統(tǒng)主要用于發(fā)電廠中發(fā)電機勵磁。
該勵磁系統(tǒng)能夠通過以微處理器為基礎(chǔ)的單通道或雙通道調(diào)節(jié)器以及可選配的附加后備電流調(diào)節(jié)器，進行自動電壓調(diào)節(jié)。
該勵磁系統(tǒng)能夠全面集成于更高級別的分級控制系統(tǒng)中。靜態(tài)勵磁系統(tǒng)(SES)基于經(jīng)年累月的專業(yè)知識以及久經(jīng)考驗的技術(shù)。它包括微處理器控制器，采用了最先進的印刷電路板技術(shù)以及高效半導(dǎo)體電路技術(shù)。數(shù)字式自動電壓調(diào)節(jié)器(AVR)模塊是一個多功能電力電子控制器。不僅能夠控制功率整流器的輸出，還具有限制器、監(jiān)控功能以及供貨范圍中列出的其它控制電路。受控的功率整流器 DC輸出配置有磁場抑制電路，以保護發(fā)電機磁場及勵磁系統(tǒng)。

PCD230A

勵磁系統(tǒng)采用整流器對勵磁電流進行控制，從而調(diào)節(jié)電機機端電壓以及同步機的無功功率流。
對于自并勵或自勵系統(tǒng)，勵磁電源來自電機機端。同步機的勵磁電流經(jīng)過勵磁變壓器和功率整流器?？梢詫⒋艌鰯嗦菲髟O(shè)置在功率整流器的交流側(cè)或直流側(cè)。勵磁變壓器將發(fā)電機的端電壓降低成功率整流器所需的輸入電壓，并隔離電機機端與勵磁繞組之間電流，并同時作為功率整流器的整流電抗。功率整流器將交流電流轉(zhuǎn)換成受控制的直流申流。
在啟動階段，起勵能量來自輔助電源。只要功率整流器的輸入達到 10-20 V，即可控制整流器和控制電子裝置，此時起始能量由發(fā)電機端子提供。
在與電網(wǎng)同期后，勵磁系統(tǒng)可以在AVR 模式下運行，對發(fā)電機端電壓及無功功率進行調(diào)節(jié)。它還可以在某個疊加控制模式下運行，即電機的Cos-phi(功率因數(shù))控制或MVAr(無功功率)控制。此外，它還可用于電廠并聯(lián)點的電壓及無功控制。

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