Cascade control system of optical fiber amplifier

A cascade control system for an optical fiber amplifier, comprising a target setting parameter module, a primary controller, at least one controlled module, and an secondary controller corresponding to the controlled module, wherein

• the target setting parameter module is configured to set a first target parameter signal to the primary controller, the first target parameter being a first output parameter desired for the controlled module to achieve;
• the primary controller is configured to generate a second target parameter signal corresponding to each controlled module based on the first target parameter signal outputted from the target setting parameter module and a first target parameter monitoring signal outputted from the controlled module, the second target parameter being a second output parameter desired for the controlled module to achieve, the second output parameter desired for the controlled module to achieve being different from but associated with the first output parameter desired for the controlled module to achieve;
• the secondary controller is configured to output a control signal to the corresponding controlled module based on the second target parameter signal and a second target parameter monitoring signal outputted from the controlled module;
• the controlled module is configured to operate as being driven by the control signal outputted from the secondary controller and generate the second target parameter monitoring signal that is fed back to the corresponding secondary controller, and the first target parameter monitoring signal that is fed back to the primary controller;
• and
• the secondary controller and the corresponding controlled module constitute an inner feedback control loop, and the inner feedback control loop and the primary controller constitute an outer feedback control loop.