动态电压恢复器（DVR）采用全控型电力电子器件IGBT，核心组成包括储能元件（超级电容）、逆变器、充电单元切换开关及旁路开关。

其接入系统的方式独具特点：逆变器采用并联设计，切换开关则串联在供电电源与受保护负载之间，形成高效的电压保障链路。

当电网出现电压暂降、暂升或短时中断等异常情况时，DVR 会立即切断输入侧电源，同时从自带的储能器件中汲取所需能量。

通过三相桥式逆变电路系统，它能快速生成与电网电压幅值、相位完全一致的补偿电压，无缝输送至负载端，确保输出电压瞬间恢复至额定值，实现负载供电零中断，为设备稳定运行提供坚实保障。

作为储能式电压补偿设备，其显著优势在于适应性极强 —— 无论单相、两相或三相电压跌落，即便跌落至 0%，都能有效治理，始终为负载提供合格电能，保障用电安全可靠。

动态电压恢复器主要有四种工作状态：

电网正常时：待机模式

此时 DVR 的晶闸管电子开关导通，负载直接由电网供电，既保证高效运行，又实时监测电网状态。

电网异常时：补偿模式

当发生电压暂降、骤升或短时中断，设备会快速切断晶闸管电子开关，同步启动IGBT 功率模块，使负载与电网隔离，转而由 DVR 独立供电，实现快速响应与隔离输出。

电网恢复稳定：恢复模式

DVR 先将输出电压波形与电网波形同步，随后接通晶闸管电子开关，让负载重新由电网直接供电；同时，系统会为储能电容柜补充损耗的能量，整个过程柔性退出、无缝切换。

故障或检修时：旁路模式

若 DVR 出现故障或需要技术检修，会自动切换至旁路回路供电；待维护完成后，设备将自动恢复正常运行，体现快速旁路与自动复位的优势。

What is Dynamic Voltage Restorer ？

The Dynamic Voltage Restorer (DVR) adopts IGBT, a fully-controlled power electronic device, with core components including energy storage elements (supercapacitors), an inverter, a charging unit changeover switch, and a bypass switch. 

Its way of connecting to the system is unique: the inverter is designed in parallel, and the changeover switch is connected in series between the power supply and the protected load, forming an efficient voltage protection link.

When the power grid has abnormal conditions such as voltage sag, swell, or short-term interruption, the DVR will immediately cut off the input-side power supply and at the same time draw the required energy from its own energy storage device.

Through the three-phase bridge inverter circuit system, it can quickly generate a compensation voltage that is completely consistent with the amplitude and phase of the grid voltage, and seamlessly transmit it to the load end, ensuring that the output voltage instantly returns to the rated value, realizing zero interruption of load power supply, and providing a solid guarantee for the stable operation of the equipment.

As an energy storage voltage compensation device, its significant advantage lies in its strong adaptability - no matter the voltage drop of single-phase, two-phase or three-phase, even if it drops to 0%, it can be effectively controlled, and it always provides qualified electric energy for the load, ensuring safe and reliable power consumption.

The Dynamic Voltage Restorer mainly has four working states:

When the power grid is normal: Standby Mode

At this time, the thyristor electronic switch of the DVR is turned on, and the load is directly powered by the power grid, which not only ensures efficient operation but also monitors the grid status in real-time.

When the power grid is abnormal: Compensation Mode

When a voltage sag, swell, or short-term interruption occurs, the device will quickly cut off the thyristor electronic switch, synchronously start the IGBT power module, isolate the load from the power grid, and then switch to independent power supply by the DVR, achieving rapid response and isolated output.

When the power grid returns to stability: Recovery Mode

The DVR first synchronizes the output voltage waveform with the grid waveform, then turns on the thyristor electronic switch to allow the load to be directly powered by the grid again; at the same time, the system will supplement the lost energy for the energy storage capacitor cabinet, and the whole process is flexibly exited and seamlessly switched.

During failure or maintenance: Bypass Mode

If the DVR fails or needs technical maintenance, it will automatically switch to the bypass circuit for power supply; after the maintenance is completed, the device will automatically resume normal operation, reflecting the advantages of fast bypass and automatic reset.