Frequency dynamic convolution (FDY conv) has been a milestone in the sound event detection (SED) field, but it involves a substantial increase in model size due to multiple basis kernels. In this work, we propose partial frequency dynamic convolution (PFD conv), which concatenates static conventional 2D convolution branch output and dynamic FDY conv branch output in order to minimize model size increase while maintaining the performance. Additionally, we propose multi-dilated frequency dynamic convolution (MDFD conv), which integrates multiple dilated frequency dynamic convolution (DFD conv) branches with different dilation size sets and a static branch within a single convolution module, achieving a 3.2% improvement in polyphonic sound detection score (PSDS) over FDY conv. Proposed methods with extensive ablation studies further enhance understanding and usability of FDY conv variants.