| 论文简介 |
Canadian Supercritical Water-cooled Reactor (SCWR) is a pressure-tube type SCWR under development
in Canada. Once-through direct cycle is adopted in the design. The reactor and the turbine are tightly
coupled. A suitable strategy is necessary to deal with the relationship between the reactor and the
turbine for safe and smooth plant operation. A turbine dynamic model is derived together with the
reactor model to complete the nonlinear plant model. Three basic control strategies: reactor-leading,
turbine-leading and feedwater-leading are applied to the Canadian SCWR. Input-output pairings of the
control systems are determined based on the different strategies and Proportional and Integral (PI)
controllers are tuned to meet the control requirements. A typical load pattern is introduced to test the
control performance. Through simulation, it is found that the load following capacity with the reactorleading
strategy is low while the fluctuations in the thermal parameters are large with the turbineleading
and feedwater-leading strategies. Therefore, a new control strategy is needed to deal with
these drawbacks. A coordinated control strategy is proposed to achieve high load following capacity with
small variation in the thermal parameters. It is established based on the turbine-leading strategy by
adding a feedforwad control system to balance the reactor and the turbine. In the feedforward control
system, the input signal is the difference between the steam pressure and its setpoint, and the outputs
are the control rod reactivity and the feedwater flow rate. In such a way, the power-to-flow ratio can be
maintained in a correct proportion to reduce the fluctuations in the thermal parameters. Simulations are
performed by introducing a typical load pattern. From the responses, it is found that the turbine power
can closely follow the load demand and the variation in the steam temperature is efficiently suppressed
compared to that with the turbine-leading strategy. It can be concluded that the proposed control
strategy is applicable for the Canadian SCWR and smooth operation can be achieved. |
(创新港)
