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From page 34... ... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 32 of 61 Table 6-6 Summary of Cost Savings in 10 Years Total Energy Cost Saving Over 10 Years (Assuming 5% Annual Increase) Year 3MW ESD 4MW ESD 1 55,152 70,917 2 57,909 74,463 3 60,805 78,186 4 63,845 82,096 5 67,037 86,200 6 70,389 90,510 7 73,909 95,036 8 77,604 99,788 9 81,484 104,777 10 85,559 110,016 Total 693,694 891,990 7 Guiding the Selection of Energy Storage Application 7.1 Selection of ESD power rating and energy capacity The ESD power rating and energy capacity are dependent on a number of parameters, such as: • Traction power system parameters, including voltage level, substation spacing, third rail (or OCS) Read the entire page →
From page 35... ... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 33 of 61 ESD Rating Requirement 1.5 3.0 4.0 3.2 4.0 0 1 2 3 4 5 Light Rail 1.5MW ESD Metro Rail 3MW ESD Metro Rail 4MW ESD Commuter Rail 3MW ESD Commuter Rail 4MW ESD Po w er (M W ) Required Power Rating (MW) Read the entire page →
From page 36... ... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 34 of 61 7.2 Load cycles Load cycles from the three simulated transit systems; light rail, heavy rail and commuter rail are shown in Figures 7–3 through 7–8. 7.2.1 Light rail Simulated ESD Load Cycle (Case 70c-5 Minute Headway) Read the entire page →
From page 37... ... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 35 of 61 7.2.2 Metro rail (heavy rail) Simulated ESD Load Cycle (Case 31-2 Minute Headway) Read the entire page →
From page 38... ... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 36 of 61 Simulated ESD Load Cycle -3,500 -3,000 -2,500 -2,000 -1,500 -1,000 -500 0 500 1,000 1,500 2,000 2,500 3,000 3,500 7:30 7:35 7:40 7:45 7:50 7:55 8:00 Time Po w er (k W ) Power (kW) Read the entire page →
From page 39... ... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 37 of 61 7.2.4 Summary Assuming daily operational headways as shown in Figures 7–9 and 7–10 and based on the simulated load cycles as shown in the above section for the three systems, the daily total charge/discharge cycles can be calculated. The total charge and discharge cycles over 1 year and over 10 years are listed in Table 7–1, together with the minimum cycle time period between successive charge/discharge cycles. Read the entire page →
From page 40... ... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 38 of 61 Table 7-1 Summary charge/discharge cycles for the 3 systems Type Cycles /year Cycles /10 years Minimum cycle time period (minutes) Light Rail 1.5MW ESD 442,800 4,428,000 0.71 Metro Rail 3MW ESD 161,120 1,611,200 2.00 Commuter Rail 4MW ESD 28,770 287,700 15.00 Note that in the above table, the light rail transit system shows the highest number of charge/discharge cycles and the shortest cycle time period. Read the entire page →
From page 41... ... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 39 of 61 7.3.1 The effect of ESD power rating on voltage improvement For the metro rail system, if an ESD is installed at position G05B at the east end of the track, the low voltage conditions will be improved. A 3MW installation is required to achieve 525V or better, as shown in Figure 7–11. Read the entire page →
From page 42... ... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 40 of 61 Simulated Train Voltages (Case 33-2 Min Headway, With ESD 4MW) 0 100 200 300 400 500 600 700 800 900 1,000 7.5 8.0 8.5 9.0 9.5 10.0 10.5 11.0 11.5 12.0 12.5 Location (miles) Read the entire page →
From page 43... ... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 41 of 61 7.3.4 The effect of headway on system receptivity Similarly, receptivity variations versus headways are shown in Figure 7–17. As expected, receptivity improves for a larger installed ESD. Read the entire page →
From page 44... ... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 42 of 61 Minimum Train Voltages by Different Installations (2 Minute Headways; 840V Voltage Limit) 497 604 558 627 655 644 593 547 634 617617 562 637 619 520 651 400 450 500 550 600 650 700 0 15 30 45 WB train headway offset (seconds) Read the entire page →
From page 45... ... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 43 of 61 System Receptivity Under Voltage Limits (2 Minute Headway) 69.5 95.74 82.93 77.46 68.62 76.3 61.7 89.7 72.17 79.24 84.38 97.41 55 60 65 70 75 80 85 90 95 100 0 15 30 45 Headway offset for WB trains Sy et em R ec ep tiv ity (% ) Read the entire page →
From page 46... ... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 44 of 61 Also, due to electrical circuit resistance losses associated with long distances between the ESD and nearby electrical substations, the charging rate is limited. A higher Vc setting positively affects train voltage level, but consideration must also be given to specification of charging rate. Read the entire page →
From page 47... ... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 45 of 61 Table 7-2 ESD Rating & Capacity vs. Voltage Improvement (Commuter Rail) Read the entire page →
From page 48... ... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 46 of 61 ESD Rating Requirement 30 35 40 45 30 35 40 45 50 55 Min Train Voltage Improvement (V) Read the entire page →
From page 49... ... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 47 of 61 Simulated ESD Load Cycle -4,000 -3,000 -2,000 -1,000 0 1,000 2,000 3,000 4,000 7:40 7:41 7:42 7:43 7:44 7:45 Time Po w er (k W ) 3MW ESD 4MW ESD2 Minute Headway Figure 7-21: Simulated ESD load cycles (metro rail) Read the entire page →

From page 34...

... Guiding the Selection & Application of Wayside Energy Storage Technologies for Rail Transit and Electric Utilities Transit Cooperative Research Program Transportation Research Board Page 32 of 61 Table 6-6 Summary of Cost Savings in 10 Years Total Energy Cost Saving Over 10 Years (Assuming 5% Annual Increase) Year 3MW ESD 4MW ESD 1 55,152 70,917 2 57,909 74,463 3 60,805 78,186 4 63,845 82,096 5 67,037 86,200 6 70,389 90,510 7 73,909 95,036 8 77,604 99,788 9 81,484 104,777 10 85,559 110,016 Total 693,694 891,990 7 Guiding the Selection of Energy Storage Application 7.1 Selection of ESD power rating and energy capacity The ESD power rating and energy capacity are dependent on a number of parameters, such as: • Traction power system parameters, including voltage level, substation spacing, third rail (or OCS)