Analytical design, software coding, field tests, field implementation of a digital Automatic Generation Control (AGC) for an electric utility. A total of 18 generators were dispatched and commanded every 8 seconds to share Area Control Error (ACE) and Base Load Deviation (BLD). The hydraulic-mechanical servomechanisms at the generating unit were interfaced to remote-terminal-units by means of a relay whose contact time was proportional to the desired MW power change. Performance of each generating unit was checked for closed loop response (the computer closes the loop) and compensation adjusted. The generators could operate in any of six modes for sharing or ramping to desired set-points. The set-point or base power of each generator, normally determined by economic dispatch, was found by water allocation between 6 dam sites where the generators were located. Every 10 minutes the water balance was used to calculate the new base power for every generator. Reservoir constraints, run-of-the-river constraints and adjustment of power output with head variation were features of the hydro allocation program.
Developed algorithms and incorporated them with the on-line database for economic dispatch of generators in an energy management system for electric utilities. The programs started with on-line topology and the state of the power system, then performed a network reduction to tie lines, generators, and a single conforming load in order to calculate loss coefficients corresponding to the present power system configuration. The computation was extremely efficient and used on a demand basis to replace the on-line loss coefficients in the classical coordination equations for economic dispatch. One application of the reduction program was to calculate gradients of transmission losses with respect to network reactive and real power. The gradients were used in an optimal power dispatch to allocate reactive injections as well as generation for the network. Line flow limits, VAR limits, and generation constraints were incorporated into either the load flow or dispatch equations. Both the load flow and dispatch were in an iterative loop. Additional responsibilities were to direct programmers in coding the above algorithms, establish analytical models for checking Automatic Generation Control codes before shipping the computer system to customers, assist on state estimation and distribution factor programs. Developed the software design for common control of power generating plants by two or more participating utilities. One aspect was interaction of the AGC systems when simultaneously regulating the plant on a 4 second basis. Another was economic dispatch of the plant which was accomplished by a block relaxation technique using each utility's dispatch program iteratively.
Design and fabrication of automatic start-up, protection, sequencing, and part of the speed and paralleling controls for a 120 kW commercial power generation system. This involved a number of turbine alternators to be scanned and started and stopped in response to system load demands and paralleled onto the power bus, and share real and reactive load.
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