diff --git a/test/host/phasor/phasor_test.c b/test/host/phasor/phasor_test.c
index f32b028e..0a14e669 100644
--- a/test/host/phasor/phasor_test.c
+++ b/test/host/phasor/phasor_test.c
@@ -26,6 +26,7 @@
  *   TC-PH-020 L2-2 实例层：实例数/实例表/未攒满一周波不产出
  *   TC-PH-021 L2-6 滑动窗：连续滑动 20 拍基波读数恒定
  *   TC-PH-022 L2-7 双区交换：使用区交替 + get 返回**最后一次** run 的结果（非陈旧）
+ *   TC-PH-030..034 phasor_zero 四字段清零 / phasor_init 双区清零 + 使用区与就绪标志复位 + 幂等
  *
  * 通过：全部 TC PASS（main 返回 0）。
  * 入口：int main(void)，返回 0=PASS / 1=FAIL（由 run 脚本判读）。
@@ -432,6 +433,45 @@ static void tc_instances(void) {
     CHECK(ok, "L2-2/L2-6 instance results == phasor_calc() on the same ring window");
 }
 
+/* ===================== TC-PH-030..034：phasor_zero / init 清零 ===================== */
+
+static void tc_zero(void) {
+    phasor_t p;
+    uint8_t  i;
+    int      zones_dirty = 0;
+
+    /* 1) 直接白盒：phasor_zero 把四个字段（含 fAm / fAmSQ）全部清零 */
+    p.fRe = 1.0f; p.fIm = -2.0f; p.fAm = 3.0f; p.fAmSQ = 4.0f;
+    phasor_zero(&p);
+    CHECK((p.fRe == 0.0f) && (p.fIm == 0.0f) && (p.fAm == 0.0f) && (p.fAmSQ == 0.0f),
+          "TC-PH-030 phasor_zero clears all four fields");
+
+    /* 2) 经 phasor_init：先把双区写成脏值，init 后必须全零，使用区复位、就绪标志清 */
+    for (i = 0u; i < (uint8_t)PHASOR_INST_N; i++) {
+        s_zone[0][i].fRe = 9.0f; s_zone[0][i].fIm = 9.0f;
+        s_zone[0][i].fAm = 9.0f; s_zone[0][i].fAmSQ = 9.0f;
+        s_zone[1][i].fRe = 9.0f; s_zone[1][i].fIm = 9.0f;
+        s_zone[1][i].fAm = 9.0f; s_zone[1][i].fAmSQ = 9.0f;
+    }
+    s_use_zone = 1u;
+    (void)phasor_init();
+    for (i = 0u; i < (uint8_t)PHASOR_INST_N; i++) {
+        if ((s_zone[0][i].fRe != 0.0f) || (s_zone[0][i].fIm != 0.0f) ||
+            (s_zone[0][i].fAm != 0.0f) || (s_zone[0][i].fAmSQ != 0.0f) ||
+            (s_zone[1][i].fRe != 0.0f) || (s_zone[1][i].fIm != 0.0f) ||
+            (s_zone[1][i].fAm != 0.0f) || (s_zone[1][i].fAmSQ != 0.0f)) {
+            zones_dirty = 1;
+        }
+    }
+    CHECK(zones_dirty == 0, "TC-PH-031 phasor_init zeroes both result zones");
+    CHECK(s_use_zone == 0u, "TC-PH-032 phasor_init resets use zone to 0");
+    CHECK(phasor_get(0u, &p) == -2, "TC-PH-033 phasor_init clears ready (get -> -2)");
+
+    /* 3) 幂等：重复 init 不改变结果 */
+    (void)phasor_init();
+    CHECK((s_use_zone == 0u) && (phasor_get(0u, &p) == -2), "TC-PH-034 phasor_init is idempotent");
+}
+
 /* ===================== TC-PH-022：L2-7 双区指针原子交换 ===================== */
 
 static void tc_dualzone(void) {
@@ -504,6 +544,8 @@ int main(void) {
     tc_instances();
     printf("-- L2-7 dual-zone swap --\n");
     tc_dualzone();
+    printf("-- L2 zero / init --\n");
+    tc_zero();
 
     printf("\n=== Phasor Tests: %d/%d PASSED (failed=%d) ===\n",
            s_passed, s_total, s_failed);