Introduction:
In an HVDC transmission system, the rotor angle difference refers to the phase difference between the AC and DC voltages. It plays a crucial role in maintaining the stability and efficient operation of the system. The rotor angle difference is influenced by various factors, including the auxiliary components used in the HVDC system.

Auxiliary Components:
The two auxiliary components that significantly impact the rotor angle difference in an HVDC transmission system are the DC line inductor and the reactive power sources. Let's understand the role of each component in detail:

1. DC Line Inductor:
- The DC line inductor is connected in series with the DC transmission line.
- It is used to limit the rate of change of current during transient conditions, such as faults or switching events.
- The inductor helps to dampen the oscillations and stabilize the system.
- It reduces the impact of sudden changes in DC current on the AC system and helps maintain a stable rotor angle difference.

2. Reactive Power Sources:
- Reactive power sources, such as static compensators or synchronous condensers, are used to regulate the voltage and reactive power flow in the system.
- They provide reactive power support and help maintain the desired voltage levels.
- By controlling the reactive power flow, these sources can influence the rotor angle difference.
- Increasing or decreasing the reactive power support can change the rotor angle difference and affect the system's stability.

Calculation of Rotor Angle Difference:
The given answer states that the rotor angle difference is 32.58 degrees. However, the calculation method or specific system parameters are not provided. Therefore, it is difficult to explain the answer in detail without further information.

To calculate the rotor angle difference accurately, various system parameters such as the DC line inductance, AC system parameters, and reactive power support need to be considered. The specific system configuration and control strategy will determine the exact impact of these auxiliary components on the rotor angle difference.

In conclusion, the rotor angle difference in an HVDC transmission system is influenced by auxiliary components such as the DC line inductor and reactive power sources. These components play a vital role in maintaining system stability and voltage control. The given answer of 32.58 degrees represents the calculated rotor angle difference, but without additional information, it is challenging to explain the answer in detail.