具有功率约束的逆变器电源电压/功率统一控制模型研究

Study on a voltage/power unified control model of an inverter with power output limitation

为了更有效和协调地控制逆变器,降低控制系统对参考电压的依赖,提出了基于电压相位控制的电源逆变器的统一控制方法。将逆变器控制为电压源,并控制逆变器输出电压的幅值以控制其输出功率不大于极限功率,同时控制逆变器输出电压的相位以控制逆变器的工作模式。电压相位控制为固定相位时,逆变器则工作于电压参考模式;电压相位随功率需要的变化而变化时,逆变器的工作模式则为功率跟踪模式。同时,逆变器两种模式间的转换过程平滑,这样消除了模式切换对电力系统的冲击。在Matlab/Simulink建立了仿真模型,并通过仿真验证了该模型的正确性。

In order to control inverters more effectively and coordinate and reduce dependence on the reference voltage of the systems,a unified control method based on voltage phase angle control for the inverter of sources is presented.The inverter is controlled to work as the voltage source,in which the output voltage amplitude of the inverter is controlled so that the output power of the inverter is no greater than its maximum power.At the same time,the phase angle of the inverter voltage is also controlled to control the work mode of the inverter.The inverter works as the reference-voltage source when the fixed phase angle of the inverter voltage is controlled.The phase angle of the inverter voltage may be controlled to follow the output power requirement,in which the work mode of the inverter is the power tracking mode.Furthermore,the two working modes of the inverter can be switched with each other smoothly.The result is that the impact from changing the working mode of the inverter on the power system can be avoided.The simulation model for the proposed control is built in Matlab/Simulink and the effectiveness is verified.