EMS: RECENT DEVELOPMENTS AND CURRENT TRENDS

Transmission & Distribution World October 1996

By Chuck Newton, Automation Editor

Last month, Newton-Evans Research undertook its fifth multiclient survey of energy management (EM) control center operations managers since 1985. Preliminary returns have been recieved from 32 of approximately 225-250 such sites in the United States. Another five utilities planning to install an EMS by 1998 have also responded.

Linkage to Other Systems

Today's EM systems are increasingly linked to external systems. The most frequently mentioned links currently in place include: simulation systems (DTS/OTS) - 42%, and historical records keeping systems - 45%. Future plans call for links to be extended outward to other neighboring utilities - 71% citing (up from 24%) and electronic bulletin boards - 50% (up from 16%). Other significant plans are in place by about one-third of the utilities for links to administrative computer systems and to trouble call management systems.

Budget Allocations

EMS budgets continue to differ significantly from SCADA budgets with more than 40% of EMS expenditures allocated to software. On an aggregate basis, about 27% of the EMS budget is allocated for master station hardware, and an equal amount to supervisory control software. Fifteen percent is allocated for power applications software. RTUS bought in conjuction with an EMS now claim about 14% of the budget, higher than found in earlier studies. About 7% is allocated for communications equipment and about 5% for training simulation - with higher actual percentages among respondents actively performing DTS/OTS upgrade or replacement.

Internal Budget Allocations

About 40% of internal spending is for EM system improvement. Another 43% is attributable to project team costs, while 10% is reserved for EMS project travel and 7% for other expenses.

Operating Systems

UNIX continues to lead the way in mentions (97%) of operating systems. Windows NT is a close runner-up (88%). VMS, the DEC-based operating system, continues to be mentioned frequently (44%), remaining ahead of Windows 95 (38%) and other Windows versions.

Improvements for Operations Staff

Two-thirds of the respondents reported that improvements are required for integrated information from other systems within the utility. The same percentage said that on-line access to data at neighboring utilities and pool-level systems was required for improved operations.

Support Maintenance Staff

Requested improvements to support maintenance staff centered on better database generation maintenance tools (92%). Most added that EMS vendors would be the likely source for assistance. Next, communicants analysis tools available from third parties, such as software firms, consultants or EPRI, were mentioned. The following requests were grouped close behind: modern debugging tools (with third parties as the source), better display generation maintenance tools, and system analysis tools for performance measurement.

Short- and Long-Term Concerns

Seven critical issues were listed. In-house methods were cited more often as the selected short-term approach over other alternatives. Longer-term views centered around the EMS supplier community and its likely development of acceptable resolutions to these issues. The issues presented in the survey included coping with changes and issues in power dispatching, meeting FERC requirements for transaction scheduling, handling LAN administration, resolving 'Year' 2000 issues, interfacing with enterprise-wide computing, integrating EMS with DMS and GIS, and resolving security issues evolving from 'opening up' control system data to the corporation.

Communications Mix

Currently, EM systems rely on a mix of three wide-area communications methods - leased lines, microwave and fiber. Two-way radio also plays a role. Communications plans center around increased deployment of fiber. No approach is close to the level of plans for adding fiber lines to network infrastructure. In addition to links from the control center to transmission and distribution substations and power plants, three in four EMS sites also communicate with one or more downline SCADA, upline pools and administrative computers.

New Applications

By 1998, available transfer capacity calculations (cited by 50%), transmission/ancillary services pricing (37%), optimal power flow (34%) and VAR/voltage control (32%) will be incorporated into the EMS operations from one-third to one-half of the sites surveyed. Upgraded or replacement software is being planned for interchange transaction scheduling and accounting (24%), energy accounting (18%) and automatic generation control (16%).