Novel Night and Day Control of PV Solar Farm as STATCOM (PV-STATCOM) for Critical Induction Motor Stabilization and FIDVR Alleviation

Induction motors are globally used in several critical operations such as petrochemicals, mining, process control, etc., where their shutdown during faults causes significant financial loss. System faults can also lead to Fault Induced Delayed Voltage Recovery (FIDVR) causing service disruptions. Dynamic reactive power compensators such as SVC and STATCOM are conventionally employed to mitigate these issues, however, these are very expensive. PV solar plants are growing at unprecedented rate globally and are likely to be installed near such critical motors. This thesis presents several novel applications of a patented technology of utilizing PV solar plants, both during night and day, as STATCOM, termed PV-STATCOM, for mitigating above issues at about 50 times lower cost than equivalent-size STATCOMs. A reactive power modulation based PV-STATCOM control is developed to stabilize remotely located motor both during night and day in a realistic distribution feeder, even when reactive power support according to the pioneering German Grid code fails. This control was field demonstrated for first time in Canada (and perhaps in world) on the 10 kW PV solar system in the utility network of Bluewater Power, Sarnia, Ontario. Another novel control strategy based on active and reactive power modulation of PV-STATCOM is developed. MATLAB/PSCAD simulation studies show that the proposed control can stabilize remotely located motor much faster and with reduced real power curtailment than conventional strategies. A new real and reactive power control of PV-STATCOM is proposed to alleviate FIDVR. Electromagnetic Transients simulation studies on a realistic transmission network show that the proposed control on a 100 km remote solar farm can alleviate FIDVR and stabilize a cluster of motors for wide range of system parameters and operating conditions. PV-STATCOM can alleviate the need of local STATCOM for achieving the same objective. Comprehensive sensitivity and stability analysis of single and two distribution level PV-STATCOMs are performed with: i) equivalent and detailed PV-STATCOM model, and ii) PV-STATCOM control implemented at plant level and inverter level. The impact of modeling details, controller location and system parameters on controller interaction, are investigated