code: def _power_mismatch_dc(self, buses, generators, B, Pbusinj, base_mva):
          
          nb, ng = len(buses), len(generators)
          # Negative bus-generator incidence matrix.
          gen_bus = array([g.bus._i for g in generators])
          neg_Cg = csr_matrix((-ones(ng), (gen_bus, range(ng))), (nb, ng))
  
          Amis = hstack([B, neg_Cg], format="csr")
  
          Pd = array([bus.p_demand for bus in buses])
          Gs = array([bus.g_shunt for bus in buses])
  
          bmis = -(Pd - Gs) / base_mva - Pbusinj
  
          return LinearConstraint("Pmis", Amis, bmis, bmis, ["Va", "Pg"])
docs: Returns the power mismatch constraint (B*Va + Pg = Pd).