Solar polar detection can greatly enrich human understanding of the solar magnetic field. However, accurate polar flybys are rarely involved in previous trajectory designs due to the requirement of an enormous amount of velocity. This paper identifies gravity assist trajectories for solar polar detection missions in patched-conic models. An analysis model is proposed to judge whether a gravity assist sequence can achieve a required excess velocity ($v_{\infty }$) at the planet encounter for the solar polar flyby. In addition to the classical Jupiter gravity assist trajectory, some less conventional paths, such as Jupiter–Earth (JE${}^n$GA), Jupiter–Venus (JV${}^n$GA), and Venus–Earth–Venus (V${}^{n_1}$E${}^{n_2}$V${}^{n_3}$GA), are examined. These unconventional trajectories can reach final short-period orbits. For JE${}^n$GA and JV${}^n$GA trajectories, two different cases are found: in the transfer process, case 1 has a shorter perihelion, and case 2 has a higher inclination. In V${}^{n_1}$E${}^{n_2}$V${}^{n_3}$GA trajectory, the aphelion distance can be reduced from 5.2 AU to 3.7 AU compared with those trajectories mainly using Jupiter gravity assist. The final orbital periods vary from 83 days to 4.1 years in the trajectories provided, and the corresponding transfer times are from 46 years to 1.2 years. In the future, designers of practical missions can choose the appropriate trajectory according to their specific needs.

太阳极性探测可以极大地丰富人类对太阳磁场的认识。然而，由于需要大量的速度，以前的轨迹设计很少涉及精确的极地飞越。本文确定了补丁圆锥模型中太阳极地探测任务的重力辅助轨迹。提出了一种分析模型来判断重力辅助序列是否可以达到所需的超速（$v_{\infty }$) 在太阳极地飞越的行星相遇处。除了经典的木星重力辅助轨迹外，还有一些不太常规的路径，例如木星-地球（JE${}^n$GA), 木星-金星 (JV${}^n$GA）和金星-地球-金星（V${}^{n_1}$乙${}^{n_2}$五${}^{n_3}$GA），进行检查。这些非常规的轨道可以到达最终的短周期轨道。乙脑${}^n$通用航空和合资企业${}^n$GA 轨迹，发现了两种不同的情况：在转移过程中，情况 1 的近日点较短，情况 2 的倾角较大。在 V${}^{n_1}$乙${}^{n_2}$五${}^{n_3}$GA 轨迹，与主要使用木星重力辅助的轨迹相比，远日点距离可以从 5.2 AU 减少到 3.7 AU。最终轨道周期在提供的轨迹中从 83 天到 4.1 年不等，相应的转移时间从 46 年到 1.2 年不等。未来，实际任务的设计者可以根据自己的具体需求选择合适的轨迹。