we are connected with maintenance of electrical distribution system in india. As u know our std frequency is 50 Hz. systen rated voltage by sypply agency is 11 KV . we installed 250 KVA 11/.433 KV transformer at our site. our Max demand is approx 210 KVA. and type of loads are lighting Mechanical laundry, traing workshops with lathe etc. We are facing problem of low pf. while checking the parameters LT voltage is 460 volts . An old power factor corrector 115 KVAR is in system but not working. How can we increase our Pf to unity or 0.99 lag. are harmonic filters also essential?