With the increase in demand for the construction of high proportion new energy base, the power transmission scale of Ultra-High Voltage Direct Current(UHVDC) is growing rapidly, and the characteristics of inter-provincial and inter-regional power transmission are affected by multiple factors, such as the randomness and volatility of new energy in the sending province, the peaks and valleys of the loads, the process of power shortages, and the new time-of use electricity pricing policy in the receiving province. Uncertainty issues are more prominent, and it has changed significantly compared with the traditional UHVDC power transmission methods. It is urgent to study the UHVDC transmission curve planning method in new period. Taking a new energy base in Northwest China as a typical example, a UHVDC power transmission system optimization model is constructed. A UHVDC power transmission curve optimization method that takes into account the power shortages process and the time-of use electricity pricing is proposed, and the Cplex12.6 Solver is used to carry out the 8760 h time series power production simulation. The results show that the obtained 12 curves by the new method can cope with the price-based response demand. Compared with the traditional method, the total cost present value is reduced by RMB 6.10 billion, the power shortage rate is reduced to 0.56%, and the proportion of new energy power is increased to 88.58%. Especially, the power output of pumped storage can track the transmission curve well, and alleviate the requirements for peak regulation flexibility of thermal power units. The power configuration scheme is technically feasible and economical, which verifies the effectiveness of the proposed method. It is suitable for the planning of large-scale UHVDC power transmission schemes. In the meantime, it plays an important role in promoting the level of new energy consumption and helping the low-carbon energy transformation.