Because power systems are complex and multi-variable, it is very difficult to realize automatic secondary load-frequency control.

电力系统一般都很复杂且变量又多，实现二阶负载—频率自动控制也相应变得很困难。

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A set of automatic control instrument of frequency and load with high reliability and convenient regulation has been produced, test of which shows theoretic analysis's correctness.

研制了一套可靠性高、调节方便的舰船电站自动频载控制装置。试验证明了理论分析的正确性。

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