Let's 1st understand what these planets represent on their own?

Sun - Sun represents Soul, Personality, King, Government, Father, Authority, Career, Top Positions, Ego, Self Esteem, Health, Education etc.

Jupiter - It is the most benefic planet and it represents all the auspicious things like Knowledge, Wisdom, Law, Guru, Spirituality, Religion, Philosophy, Literature, Elderly People and Children etc. For a girl, Jupiter also represents Husband.

Ketu - Just like Rahu, Ketu also represents Illusion as both are ilusionary planets but the difference is that Ketu is also the one who removes the illusion and brings enlightenment. Besides this, Ketu represents Isolation, Separation, Spirituality, Mystical World, Other Dimension means things related to Alien World, also represents Son, Dog, Intuition, Research Ability, Curious Nature, things which we have already achieved in past life and not much concerned to perform in this life. 

3 planetary conjunction - Whenever 3 or more planets are conjunct with each other in a house/sign then things related to that house/sign become a kind of life focus for person. It is because of huge accumulation of energy within 30 degrees of sky. It means not only these 3 planets' energy is going into this house/sign but the energy of at least 4 to 6 house/sign is going into this house/sign as these planets will be ruling some houses too. So, this house/sign with conjunction becomes almost the most important house in chart. During Career Consultation, I give a huge importance to any such house which has 3 or more planets in it.

House Ruler - Besides these karaka things, Sun, Jupiter & Ketu will also rule some houses in your chart and will represent things related to that house. Of course we can't cover conjunctions Ascendant and house wise else it will never be over. So, you have to include things related to the houses at the time of interpreting this conjunction. Also, we need to keep in mind all Yogas and Raj-Yogas which their conjunction would be making to completely understand the conjunction. Here, we can only cover meaning as per karakas.

Meaning of Sun-Jupiter-Ketu Conjunction - This is another of those conjunctions where person is born during eclipse season and near solar eclipse. The nearer he is born to solar eclipse, the more troubles he can have in his relations with Father, Authority or in finding the right career. Common theme around Jupiter and Ketu is Spirituality. They both also make person knowledge and research oriented. So, it shows someone who finds his career or authority or confidence through knowledge, wisdom and spirituality. So, we can understand this conjunction as one which 1st leads the person to different wrong paths in career and at last person gets everything sorted out when he realizes that his true path is in spiritual realm or in knowledge oriented field.The more they gain knowledge and share knowledge, more they will feel confident or authoritative in life. This can also make person spiritual and kind of seeker rather than believer. They will try to find out the Truth rather than only believe in it. Father can be in similar knowledge related field but due to association with Ketu, they may have a physical or psychological disconnect with father. 

Who will win the Conjunction? - Ketu is impacting both Jupiter & Sun, so Ketu is winning this conjunction.

Dignity & Strength - 

This conjunction can do best in signs like Aries, Cancer, Leo, Scorpio, Sagittarius and Pisces. This is where Jupiter-Ketu get the best environment to get and share knowledge. In other signs, it depends on dasha and the environment of the sign to get the best results.