US Patent 10961835 Automated rate control system for hydraulic fracturing

A method for hydraulically fracturing a subterranean formation includes preparing and sending a first command signal from a master controller to a plurality of pumps of a pump system. The first command signal specifies a flow rate output for each in pump to achieve a first target flow rate for a fracturing fluid being injected into the subterranean formation. A pressure of the fracturing fluid injected into the subterranean formation at the first target flow rate is monitored and, based on the pressure, the master controller determines when to increase a flow rate of the fracturing fluid to a second target flow rate. The master controller prepares and sends a second command signal to the plurality of pumps to specify the flow rate output for each pump to achieve the second target flow rate.