This paper proposes a differential feedback laser chaotic system to realize complex ultra-flat bandwidth chaos and secure communication between new energy stations and cloud platform. Differential calculation is introduced into the electro-optical phase feedback loop. The amplitude and phase encryption of the signal are realized simultaneously through AM and PM. The signal encryption and decryption are realized using polarization multiplexing/demultiplexing and chaotic synchronization. The results show this scheme can generate broadband, complex, and delay-hidden chaos, thereby ensuring signal security. The chaos has a PE of 0.996, an SE of 0.95, and no time delay in exposure on ACF and DMI. This method is transparent to the modulation format of the transmission signal and can achieve simultaneous communication of multiple high-speed signals. A 300Gbit/s secure communication through WDM is shown in the simulation. The confidential communication between multiple new energy station signals and the cloud platform with high-speed, safe, and noise-resistant performance is realized.