Propulsion system of boat

A propulsion system of a boat, the propulsion system comprising:

• at least a first propulsion device and a second propulsion device, which are provided side by side in a horizontal direction on a hull;
• and
• a controller including at least a processor and a memory, the controller being configured to control dynamic power of each the first propulsion device and the second propulsion device and a direction of the dynamic power, wherein
• the controller sets directions of the dynamic power of the first propulsion device and the dynamic power of the second propulsion device to be opposite to each other while being inclined around a yaw direction with respect to a reference position, when the hull moves either forward or rearward, and conducts bogen control of applying thrust to the hull, and
• during the bogen control, the controller calculates a first reference angle around the yaw direction with respect to the reference position for the direction of the dynamic power of the first propulsion device based on a thrust instruction value given to the hull and a second reference angle around the yaw direction with respect to the reference position for the direction of the dynamic power of the second propulsion device based on the thrust instruction value given to the hull, and
• upon receipt of a steering instruction, the controller calculates a first steering command value based on the steering instruction value and the first reference angle, and also calculates a second steering command value based on the steering instruction value and the second reference angle, and
• the controller controls the direction of the dynamic power of the first propulsion device, based on the first steering command value, and also controls the direction of the dynamic power of the second propulsion device, based on the second steering command value.