You are presented with multiple paper abstracts, alongside the associated literature review and chapter titles. Given the provided information, you are going to do a literature review. Please generate a coherent literature review that synthesizes the content, draws connections between different works, highlights major findings, and identifies any gaps in the existing research.

Literature Review Title: Grid Ancillary Services From Doubly Fed Induction Generator-Based Wind Energy Conversion System: A Review 
Chapter Title:  D. FREQUENCY CONTROL 
1. Abstract of Cited Paper (BIB001):  As wind power penetration increases and fossil plants are retired, it is feared that there will be insufficient kinetic energy (KE) from the plants to support the system frequency. This paper shows the fear is groundless because the high inertias (H cong 4 seconds) of wind turbine-generators (WTGs) can be integrated to provide frequency support during generation outage.

Literature Review:
Unlike the conventional synchronous generators, the increase in wind generators does not increase the system inertia. As a result, wind generation will have an impact on power systems frequency variations during disturbances. Therefore, wind turbines should adjust their inertial response characteristics to support system frequency variations BIB001 . Figure 14 shows a typical power system response after power loss. It can be inferred form this figure that larger systems FIGURE 14. Typical power system response after power loss BIB002 .