If it is possible at all, can you help me with a  PCF that calculates the distance between the price and the VWAP on a 15-min chart? 

Also, is there a way to tell that the 15-min VWAP is rising or declining?

Thanks

While it is possible to calculate distance between price and a Moving VWAP, it is not possible to calculate the distance between price and plain VWAP indicator which resets at the start of each day.

The reason for this is that there is no way to determine when the trading day start and ends, the time of day of a particular bar or the number of bars which have passed so far in the trading day in an intraday Personal Criteria Formula.

You can however create conditions based on the plain VWAP indicator by clicking on the VWAP indicator and selecting Create Scan Condition.

Create Conditions from Your Chart

So you could select Create Scan Condition and choose Moving Up or Moving Down to create a condition for the VWAP indicator increasing or decreasing.