High penetration level of renewable energy has brought great challenges to operation of power systems

and use of flexible resources (FRs) is becoming increasingly important. Flexibility of power systems can be improved by changing generation arrangements

but the interests of some market participants may be harmed in the process. This study proposes a stochastic economic dispatch model with trading of flexible ramping products (FRPs). To calculate changes in revenue and reasonably compensate units that provide FRs

multisegmented marginal bidding for energy is simulated by linearizing generation cost

and an optimal market clearing strategy for FRPs is developed according to changes in clearing energy and marginal clearing price. Then

the correlation between prediction errors of wind speeds among different wind farms is determined based on a joint distribution function modeled by the copula function

and quasi-Monte Carlo simulation (QMC) is used to generate wind power scenarios. Finally

numerical simulations of modified IEEE-30 and IEEE-118 bus systems is performed with minimum comprehensive cost as the objective function. This verifies the proposed model could effectively deal with wind variability and uncertainty

stabilize the marginal clearing price of the electricity market

and ensure fairness in the market.