Security issues for mega penetration of photovoltaic power generation in future electric power systems. A case study of stability for power swing oscillation using the IEEJ WEST 10‐machine model

Abstract

SUMMARYMega penetration of photovoltaic power generation (PV) will be introduced in future electric power systems, dealing with environmental problems such as global warming and energy exhaustion. The authors have pointed out that difficulties will arise in meeting the N-1 security standard if increases in uncertainties cannot be avoided due to PV penetration. Thus, we have proposed a new concept of "robust power system security" together with several conditions to be satisfied in order to guarantee the N-1 security standard under uncertainties. In this paper, (1) a model of uncertainties due to PV generation is proposed based on robust power system security; a method for proper parameter selection is also provided. Then, (2) the influence on the stability of the PV and load disconnection from the power system is studied through simulation using the model system; (3) the effect of PV fault ride-through (FRT) on stability is investigated along with dynamic voltage support (DVS). Finally, it is shown that (4) complicated and burdensome tasks will be considerably increased in power system operation planning and real-time operation under future circumstances by the mega penetration of PV.

A Study on the Power System Security under Future Uncertainties

“…[4], and the data accompanying the security evaluation uses Ref. [12, 13], the planned values for the August 2030 peak slot in the future slot uses Ref.…”

“…The demand for the annually maximum peak slot in a 60-Hz system in 2010 is 93 GW [12] and this demand is 108 GW in 2030 [4]. Note that in the slots for 2010 and 2030, the upper limit of the system supply capacity keeps the reserve margin at about 8% of the maximum power demand, and the lower limit is set to be 30% of the upper limit (lower limit for general thermal power generation).…”

“…Addition of fault ride through (FRT) function to PV [4] The simulations are performed with an FRT function added to PV so that PV operation can be continued even if a system fault such as instantaneous voltage drop occurs in the system. Addition of fault ride through (FRT) function to PV [4] The simulations are performed with an FRT function added to PV so that PV operation can be continued even if a system fault such as instantaneous voltage drop occurs in the system.…”

“…With its arising future importance, its penetration (or introduction) is expected to increase. We have figured out problems that it becomes difficult to maintain the supply security against the increasing uncertainties such as large PV output fluctuations due to irradiation condition [3,4]. Thus, a sharp increase in PV installment is expected [1].…”

“…When PV is penetrated on a large scale in a power grid, problems such as voltage adjustments for the distribution grid, deficiency in adjustment to absorb output fluctuations, and frequency fluctuations have been pointed out [2]. We have figured out problems that it becomes difficult to maintain the supply security against the increasing uncertainties such as large PV output fluctuations due to irradiation condition [3,4]. While the concept of decrease in security can be understood intuitively, quantitative evaluation was not available.…”